Why the Nailhead?

[55PackardGuy]

The Buick "nailhead" of the '50s and '60s was eventually discontinued and replaced with another excellent Buick V8. I've always wondered what advantages Buick engineers saw in the unique cylinder head arrangement, and why the design was abandoned--and never replicated by any other manufacturer to my knowledge.

So, Nailhead fans (me included) what say you about the theoretical and practical advantages of the famed design? What I remember most about it was the tail-twisting torque that made a massive Electra feel light as a feather, and the impeccable reliability of the big 401.

And secondly, how about the origins of the popular name for this design? I have heard at least two different explanations for the Nailhead terminology. The most common is that it referred to the small valve diameters, which made the valves (particularly the exhaust) look like "nails." The other story was that the vertical orientation of the valves made their motion like pounding in nails, albeit upside down.

A true history of the origins of the Nailhead name would be an interesting find. I wonder if there were any references in the annals of Buick, or if it was a purely customer-applied name. Sounds like something that could have its roots in the racing circuit.

So, to sum up:

1. What was the theory behind the nailhead design and its practical advantages, and why was it discontinued and never replicated?

2. Where'd that unforgettable name come from?

[Guest BJM]

Guy,

The best thorough explanation I ever saw was from a book called "Buick - The Post war Years" by Norbye and Dunn I believe. I no longer have the book but basically the reason for the straight up cylinder head was for room considerations not power output at all.

The body engineers gave the drivetrain team the specifications and the engineers tried to build the largest displacment motor they could in the confined (relatively speaking) space of the engine bay.

Remember the Chrysler Hemi? It took up so much space it restricted steering angle and turn to turn capability.

The Nailhead was considered a "semi-hemi" and was oversquare with more bore then stroke. This produced the torque that owners of the big cars of the fifties wanted. They cared less about the ability of a motor to pull from a certain rpm on. They mostly wanted capable performance around town and between towns. This was the 50's after all, when there still were not a lot of super highways and four lane divided's.

The Nailhead design lasted from 1953 to 1966 and by that time two things had changed. Highways were more available. Folks relocated or traveled greater distances between suburbs and work or shopping. So, having a more balanced bore/stroke would allow effortless cruising with numerically lower rear axle ratios.

And, pollution controls and concerns were on the horizon. It was not felt that the Nailhead design could be made efficient enough for some states (read: California) and might not have the configuration to allow bolt on pumps and pollution control devices. Plus, all GM divisions were encouraged to move toward more modern engineered engine designs/families with greater flexibility and lighter weight.

Racers initially named it "Nailhead" because the exhaust valves were so small, they looked like nails. Racers had a love/hate relationship with the Nailhead. They loved it's initial launch characteristics but hated the fact that it was tapped out at such a low rpm. Supposedly, they could not get it to breathe better for high rpm racing, so it never saw great acceptance as a quater mile race engine.

But with the semi-hemi combustion chamber and great power to weight ratios I think it came down to the ability to throw a motor in a car and go. With a Nailhead, you could put larger valves in and increase breathing (bigger, higher lift cam for instance) but that took machine work. Why not just use a hemi which had more flexibility out of the box or other options including the new Chevy small block.

I remember a part of the Norbye book related to why they ended Nailhead engineering at the 425 and it said it was because they had reached the limits of the Nailhead engine. 425 cubic inches meant the engineers had to monkey with the timing specifically the advance to limit detonation and poor engine performance because Buick owners demanded a smooth running, quiet engine, not hairy rumpa-rumpa idle. And the 425 was at that limit.

So it served the Buick division so well in it's 13 years of production. Countless millions of Nailheads were built. I have owned several vehicles with 425's in them and a few with 401's. In my experience, it's amotor that just won't die but the 425 wears out sooner then the 401. The 425 becomes harder to tune just right.

That's what I know off the top of my head. I hope that helps.

[NTX5467]

As mentioned, vehicle body design was something of a limiting factor in engine designs as the industry transitioned from "inline 8s" to "V-8s". The addition of power steering, power brakes, cruise control, and factory a/c made some of the GM underhoods highly crowded back then.

As for the Chrysler Hemi, it's a wonder they ran as well as they did as the exhaust manifold was tightly-configured to the side of the block, obviously for chassis clearance. Not very "free flowing" as the intake side of things!

From the Nailheads I've seen, the intake ports in the intake manifolds were also pretty small, compared to later designs. I suspect the ports are similarly "high velocity" due to their smaller sizing, which would also explain the lower rpm orientation as compared to other engine designs. In order to "fix" that, it would have taken a new cylinder head design (with appropriate manifolding to match), so why not just put a new block under the new heads and moderninze things too? Casting technology had advanced such that later engine designs were generally lighter than the ones they replaced.

I recall an article in a "Peterson's New Car Annual" for 1966. It was a page on the Skylark GS, with the 401 in it. They mentioned that the Nailhead V-8 had torque "for days" (or something like that) due to the smaller valves (hence the name "Nailhead") AND the longer valve timing, which resulted in a large torque curve that would take the car well into the triple-digits without breathing hard (or something to that effect). And it was THAT comment about the relationship of valve sizing and camshaft duration from which I later (in the late 1970s) came up with a formula to compare cam duration and valve sizings with respect to engine size--as a comparative tool to keep particular performance characteristics of a known combination with other engine sizes of the same engine family.

Just some thoughts,

NTX5467

[Philippe Racicot]

I really like the 401 in my Wildcat, not as powerful as the 430 in my Riv but it runs very well, and it's more durable than the newer 430-455 Buick V8 engines as it doesn't have the bottom end oiling problems of the newer Buick engines and it has a stronger forged steel crank. My Wildcat is also more fuel efficient than my newer Buicks are. I know that it also pollutes a bit more as it runs much cooler than the 430-455 but I prefer it that way! One thing that the '65 and older Nailhead engines lack is valve seals... That's why they often smoke!

[55PackardGuy]

Interesting, informative replies-- as usual from the "Buick guys!"

Somehow I thought the term "nailhead" must have come from the racing circuit. Thanks for confirming that! And the intake valve size makes the most sense as the inspiration for the name, as I've usually heard it was.

I wonder though about the "oversquare" design of the nailhead limiting top-end performance as much as the small valves and ports did. The short-strokers are often the higher-rpm motors, due to decreased piston speed versus the long-stroke designs. You'd think that if it was free-breathing, a short-stroke engine would make a good racing design.

Never thought of engine-bay size as a deciding factor in the design. But those older cars did have some restrictions. There was PLENTY of room for the 401 in my '65 Electra. I had two different engines in it, and NEITHER of them smoked--even a 100K plus miler. BUT, I never got the gas mileage with that car that my dad's 430-powered '69 Electra did. I think the fact that the 430 seemed happy with a lot of ignition advance made that the case, and also was the reason the 430 didn't feel as torquey as the 401. The 430 pinged like crazy, too, even on premium. It probably ran pretty lean.

I always thought the nailhead was a natural "wedge" combustion chamber design... not a "semi-hemi." It would seem to make sense as a wedge, with the valves coming straight down as they did.

Thanks for the history lesson!

[NTX5467]

I believe that the valve seals were deleted on the exhaust side rather than on the intake side--from something that I read a good while back (about oil smoke upon restarts when hot). Generally, the lack of exhaust seals on the exhaust valves would not impact oil consumption (as there's pressure in that side of things rather than a vacuum), but no seals on the intake valve would.

The other thing I ran across not long ago was that if valve stem to valve guide clearance was below a certain value, there would be no oil consumption issues on the intake side. After all, as my machine shop associate pointed out (when we were having a discussion of the various styles of small block Chevrolet valve seals), there has to be a little oil get down the stem for lubrication, which is why the "o-ring" seal on the small block Chevrolets was really a much better valve seal than the "Perfect Circle" scraper valve seal or the "Studebaker" cup seal was.

When the "oversquare" engine designs came out, they were advances and modern with respect to prior designs (which typically were inline motors). The short stroke allowed higher rpms for many reasons, but the torque issue would be more related to the length of the connecting rod (and the associated issue of piston side loading) with respect to the stroke length. Long-rod motors allow more "dwell time" at TDC and BDC and a more gradual transition away from TCD and BDC, whereas shorter-rod motors (with respect to the stroke length) have less dwell time at TDC and BDC and put more "yank" on the mixture column on the intake stroke because of that.

For example, the Chevy 302 (Z-28 motor, at 4" bore x 3" stroke) has a rod ratio of about 1.9, whereas the longer stroke (with a shorter rod to compensate for the stroke length without an altered block deck height) Chevy small block 400 is more like 1.57.

The shorter strokes also allowed for shorter cylinder blocks and more compact engine designs, which would fit under the anticipated "lower, longer, wider" generation of vehicles that would be unveiled a few years later. More power from less engine weight was also, I suspect, a consideration.

Another consideration of engine power output is the number of cylinders for a particuar displacement. In an article on the (at that time) possible Chevy-use LS-architecture V-10, it was mentioned that a V-10 (or V-12 for that matter) for a given displacement, would make more power than a similar V-8 due to the greater surface area of "piston crown" area of the piston) with the greater number of cylinders. There will also be some other side issues as smaller valves (in smaller cylinder bores) for higher mixture velocity, which coupled with some effective intake "ram" tuning, could result in even more power due to more effectively "packing" of the cylinder with mixture.

In the early decades of the 20th Century, more cylinders meant more smoothness and more power. Still, there was a trade-off between more cylinders and greater internal friction (which would be a siginificant issue with things like Indy car engines) from more pistons and more crankshaft bearings. In those earlier times of huge engines with little horsepower, engine internal friction would make a greater percentage of total power output than if they had made as much horsepower as any engine of that size would have made in the 1960s. In more current times, getting friction "out of the motor" means better power and better fuel efficiency (and fewer emissions, possibly).

With respect to the turbocharged Buick 3800s that were in the later Pontiac Firebirds, rather than the normal 3800 cylinder head, they used a narrowed Buick 3300 V-6 cylinder head. The reason was that the 3300 head was narrower as the 3800 head was too wide for that particular engine bay.

An engine's ignition timing requirement (and "tolerance") has a lot to do with the efficiency of the intake manifolding and cylinder head configurations. In other words, more advance is needed if it takes longer to "light the fire" of combustion in an engine.

The Chevy W-engine (348,409) only needed about 32 degrees of total ignition advance to make power, whereas the small block Chevy can tolerate between 38-40 degrees for max power. The Chevy 348/409 was somewhat legendary in the medium duty truck areas, with respect to power and load hauling capacity. One former dump truck operator said that when his truck and a similar diesel-powered truck would leave the gravel pit with equal loads, if he could get out first, the diesel would only see tailights for a little while (as they faded into the distance). Seems that this highly frustrated the diesel dump truck driver. ONLY thing was that he had to keep the rpm below 4000rpm--period. In other words, the W-engine was more low-to-mid range rpm oriented when compared to the small block Chevys that everybody knew how to make work. Same tricks and operational modes did not work on the W-engine as they did with the small block (i.e., spark advance curves, higher rpm shift points). But when that design evolved into the later 396, things changed and everybody seemed to be happy.

As the "Rat" block Chevys evolved, they had a good torque curve. As power levels were increased, it was discovered that there were "good" ports and "bad" ports in the same head. Later, it was determined that this was a method of broadening the torque curve (consider an inline engine with a "log" intake manifold having pairs of cylinders that will "tune" at different rpm levels)--which was proven when aftermarket cylinder head manufacturers built heads with all "good" ports. With all "good" ports, the engines became more peaky in torque and lost some of their earlier tractibility from the broader torque curve.

I beleive it would be HIGHLY INTERESTING to have a discussion with some of the design engineers/operatives of the Nailhead and later Buick V-8 engines. To find out some of the reasons they did some of what they did the way they did it. If some of the traits of Buick V-8s were "designed for" or were serendipity when a particular combination of factors was put all together in a particular engine.

Just some thoughts,

NTX5467

[Philippe Racicot]

My 65 401 smokes when I start it and it's still below 100K. After a few seconds, it stops smoking. It also makes a lot of blue smoke when I drive it at high speeds (90+ MPH) and floor it. And I mean A LOT! Once it begins producing smoke, it won't stop until I release the accelerator and if I just want to maintain the speed above 80, I only see blue smoke in my rearview mirror! My '67 Riviera with a 430 did that to me twice with a newly rebuilt engine, I don't drive it as much as the Wildcat and I don't drive it as fast either so that's probably why it happened only twice. A mechanic told me that this was probably caused by the PCV valve that breathes oil at high speed or something like that.

The 401 engine doesn't seem tired and there is no blowby like there was in all my 350, 430 and 455 engines did when they neared 80,000 miles.

As for pinging, the 401 seems to be a bit more prone to it with too much advance on the ignition timing but that happens on my 430 and 455 engines too.

I also heard that the 430 engines were supposed to be more fuel efficient than the nailheads but that's not what I experienced. Botm my '67 Riv and my '65 Wildcat weight about the same, The Riv has a slower axle ratio and air conditionning which doesn't help it but the Wildcat is much more fuel efficient. As for my '75 Electra, it has a 2.73 axle ratio that should help fuel economy (compared to the 3.07 in my Wildcat and the 3.42 in the Riv) but it's heavier than both and the anti-pollution stuff doesn't help getting better fuel mileage (but it helps getting poorer performance!).

[NTX5467]

I suspect you need to locate the PCV valves on the earlier engines so you'll know where they are so you can clean them or replace them. The factory valve covers (that are set-up for pcv valves) and other places the valves plug in should have a baffle under them so prevent or lessen any tendency of the valve to cause oil to enter the engine from that route. At WOT, the flow of the pcv valves is not nearly as great as it will be at part throttle.

I feel safe in mentioning that the type and amount of oil smoke you describe is NOT normal or "by design". A little smoke upon start-up would most probably be due to oil that made it's way down the valve stems when the engine was stopped, yet when middle-1980s Chevy 305s did that, they issued a TSB and built a parts package of every valve stem seal ever used on a small block Chevy V-8 to fix the problem. Just because the engine(s) you might have did not have valve seals on them when they were torn down does not mean there are not some valve seals from other Buick V-8s or other makes of engines (which have the same valve stem diameters to deal with, for example) that would work and get the excess oil out of the intake tract or exhaust flow.

The fuel effeciency of the 430 is most probably a "sweet spot" situation with the particular bore & stroke, cyl head porting and combustion chamber design, high compression ratio, cam event timing, AND certain rpm ranges that further exploit the metering efficiency (in THOSE related air flow rates) of the Rochester Q-Jet carb that came on those engines. The axle ratio/tire size on the Electras that were generally mentioned would have an influence regarding road speed vs. engine rpm at cruise.

The later 455s were victim to several things, I suspect. Foremost would be the compression ratio drop and then particular emission controls that made the engine even less efficient (power and economy). These changes would also impact the fuel metering curve of the Q-Jet, too. Plus the cars were generally heavier than in prior times, too.

Just some thoughts,

NTX5467

[55PackardGuy]

Philippe,

Neither of my 401's smoked or used any oil, but neither of them had PCV systems either!

I do know what they're talking about when they say the PCV might "breathe oil" at high rpm. You can even check that yourself, at least I was able to do it on some engines; just pull the top of the air cleaner, locate the "breather" hole, giver 'er the gun and watch for a stream of bluish fumes scoot over to the carb air horn from the "breather."

I put "breather" in quotes because, theoretically, that hole is meant to be a fresh-air INLET to the crankcase. I can't say for sure, but I always suspected that the reversal of this flow meant that there was enough blowby at high engine speeds to pressurize the crankcase and cause vapor to be pushed out the other way.

It kind of makes sense. If you just have a "breather cap" on the valve cover like I did, you can start getting oil fouling on the cover and down the side of the block if there's a lot of pressure in the crankcase.

How do you know your 401 doesn't have blowby? Compression check OK?

Does it use a lot of oil?

[55PackardGuy]

NTX,

I hear ya on the small-block smoking on startup. Lots and lots of folks never fixed this, because the tiny bit of oil leaking past the intake valves into the cylinders at rest didn't even register as any "consumption." The smoking lasted only a few seconds, and I suppose if you were the proud type of Chevy owner, you could just make sure no one was around when you first started it up! Boy, but did the back sides of those intake valves look crusty after a bunch of years of that leakage, though.

Thanks for all your great insights. I haven't seen anything in a long time about the old "W" big-block 348 and 409 truck engines. (People tend to forget, they were DESIGNED to be "diesel-beaters" in heavy trucks, not hot car engines.) Regarding the "396", it is true, is it not, that the actual displacement of that engine was 402 ci, but in automotive applications Chevy had sworn off anything more than 400 ci for their midsize cars--hence the "Chevelle 396" for political correctness... maybe insurance purposes, too? The truck version, I believe, was always honestly rated at 402 ci.

I hope you get more information from some of those Buick engineers. I'm especially interested in any more reasoning behind the "nailhead" cylinder head design.

It's very interesting how they maintained the upright position of the heads and valve covers even on the Buick design of the little 215 V8 engine, which was already a pretty compact unit. I still think there must have been some advantage to that head design beyond keeping the physical engine size narrower...

[Philippe Racicot]

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">Philippe,

Neither of my 401's smoked or used any oil, but neither of them had PCV systems either!

I do know what they're talking about when they say the PCV might "breathe oil" at high rpm. You can even check that yourself, at least I was able to do it on some engines; just pull the top of the air cleaner, locate the "breather" hole, giver 'er the gun and watch for a stream of bluish fumes scoot over to the carb air horn from the "breather."

I put "breather" in quotes because, theoretically, that hole is meant to be a fresh-air INLET to the crankcase. I can't say for sure, but I always suspected that the reversal of this flow meant that there was enough blowby at high engine speeds to pressurize the crankcase and cause vapor to be pushed out the other way.

It kind of makes sense. If you just have a "breather cap" on the valve cover like I did, you can start getting oil fouling on the cover and down the side of the block if there's a lot of pressure in the crankcase.

How do you know your 401 doesn't have blowby? Compression check OK?

Does it use a lot of oil? </div></div>

Guy,

All the 1965 Buicks have a PCV system. The PCV valve is located on the passenger side valve cover.

What you are refering to is the closed PCV system that was used in California only in 1965-67 and in all cars starting in 1968. The difference between the open and closed systems is that the open one still used a breather oil cap and the closed one had a sealed oil cap and a hose that connected to the air cleaner snorkel (in 1965-67 California emissions) and directly in the air cleaner (1968 and later, nationwide). The reason for using a closed PCV was to allow the engine to burn the exess crankcase fumes that the PCV system wouldn't burn in case of a PCV valve failure or if engine produces too much blow-by.

My car uses very little oil, about one quart for 3000 miles and there is some leaking... I didn't do a compression test but I disconnected the PCV valve and checked for blow by.

[55PackardGuy]

I guess I see how a system using a breather cap could still have positive crankcase ventilation if no road tube is used. I didn't know that some early "open" systems used breather caps. I suppose they just vented the vapors that ordinarily had exited via the road tube into the intake and allowed the other end to take care of itself. I never heard of them having a PCV valve.

I've heard that if all is well with the engine, there should be enough vacuum on the "inlet" side (valve cover oil fill hole or PCV hose) to make a parts tag "stick" to it. I would say that checking it at high engine rpm would indicate whether the vacuum turns into back-pressure. Do you check for blow-by at higher rpm, too?

Thanks for the information. What year did they do away with road tubes and change to positive ventilation, and did the early "open" ones use any kind of PCV valve?

[NTX5467]

Guy, it is correct that the Chevy W-engine was originally designed from truck use. The compression ratio differences between car and truck engines were in the piston rather than the combustion chamber sizing (as that part of the head was basically machined "flat", unlike other cylinder head which had "recessed" valves and a generally flat-top piston. The combustion chamber was actually in the cylinder bore, between the cylinder wall and the top of the piston. I suspect this would have made for a "high turbulence" combustion chamber, from the way it looks.

When Ford brought out their 332/352 "FE" series V-8 in 1958, Chevy needed a larger engine than the 283, so the easiest and quickest way was to scab the truck 348 and put it into car use. Plus, the 1958 Chevrolet cars gained size and weight that year too! The W-engine was a pretty neat design, all things considered, as it was about the same length as a small block Chevy V-8, but had larger bores and displacement expandability.

The original Chevy 396 was actually that displacement number. There was a corporate policy in effect at that time that no intermediate-size GM car could have a factory-installed engine greater than 400cid. In 1971, when lower compression (generally 8.5 to 1) was also a GM corporate policy, the Chevy 396 was overbored about .020 and resulted in the 402cid displacement version. In some cases, the "396" identifier was used and in the light truck models, it was "400" (which could be somewhat confusing as there was a 400cid small block engine that was used in light trucks in some years too).

I beleive the first year for a big block 1/2 Chevy pickup was 1968, as "396". In 1970, the small block 400 was used in Chevy cars and pickups, but I believe that in the 1971 ad 1972 model years, the "402" big block was used and identified as "400" (in at least one of those model years). The former owners of those early 1970s Chevy C-20s and C-30s that had the 402 in them still rave about how good that engine "worked" when they needed it to (hauling weight or pulling trailers), plus the somewhat normal "I should have never got rid of it!" comment (either by actual statement or tone of voice).

Many people have observed that a 396 piston at +.020 is not the same as the "standard" 402 piston, although it would appear that they should be the same. The difference, I suspect, is in the weight of the piston and how it would affect the factory balance of the motor when they were replaced (i.e., a 396 that was bored +.020 when it was rebuilt). In the factory realm of things, all pistons to an oversize of +.030 (and possibly +.060) were all the same weight. That would mean that all GM pistons for the 396 would weigh the same and "balance" the same if one was replaced and the rest were not. Therefore, the "standard" 402 piston would be heavier, yet all of the 402 pistons would weigh the same (for GM replacement pistons). If the engine builder "balanced" the motor, then these piston weight differences would be a moot point as aftermarket pistons don't always weigh the same as factory pistons for the same motor would. But when a dealership mechanic needed to replace just one piston on a warranty or customer-pay repair, using the GM piston to do it with would keep the balance "in spec" and everything would be fine in that respect when the repair was finished and delivered to an apprehensive customer.

OH . . . I ran across a copy of "Vintage Motorsports" magazine at Borders tonight. On the cover is a Kurtis-Buick 500X race car. Seems that the first years of Kurtis racers used DeSoto Hemi V-8s, but later some Buicks were in the mix too. Seems that Kurtis was a DeSoto dealer at the time and later dropped the DeSoto franchise and replaced it with a Buick franchise. It noted that the Buick 322 V-8 was extensively modified with Stu Hilborn direct fuel injection, Crane cams, and other speed equipment of the day to make (right at) 315 horsepower. Later, it mentioned that the 322 was bored and stroked to 364cid for later versions. Plus, mention was made that when the starter button was activated, it was loud enough to shake your teeth fillings loose. Quite an interesting and neat article on a highly successful race car with Buick power--back then!

Several of the Hemmings' family of car magazines also had some neat articles on Buicks too! Even one of the customizing/rodder magazines with a '57 Buick wagon that was being highly customized as it would have been done back then--looked pretty neat. LOTS of Buicks in magazines, it seems, these days!

Enjoy!

NTX5467

[Philippe Racicot]

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">

Thanks for the information. What year did they do away with road tubes and change to positive ventilation, and did the early "open" ones use any kind of PCV valve? </div></div>

I think that the last year for the draft tube was 1962 (not sure). I'm sure that the '64 had a PCV.

[55PackardGuy]

Some of the folks with the 348 in their cars were maybe a little regretful when they went to the gas pumps--pretty notorious "gas hogs." However, the Ford 352, which found its way into cars, wasn't any better from what I've heard. The fuel efficiency of the truck-based "big blocks" seemed to lag behind the purpose-built auto engines. Higher internal parasitic weight perhaps? Cooler operating temps?

Getting back to the Buick "nailhead," it's interesting the amount of peak torque these engines produced compared with the big-block Chevy's. Notable is the '65 Chevy 409, which in its hairiest version produced 425 ft lbs or thereabouts, while Buick touted "445" so proudly they put it on the air cleaner cover.

Just what was the secret of the high torque output of the Buick? Compression ratio?

And back to the question for Philippe, (or whoever would like to tackle it) did early "open" PCV systems use a PCV valve? And, if so, where was it located? The reason I didn't think my '65 vintage 401s had PCV systems was I never heard of servicing any valve.

[NTX5467]

I think that one reason the Chevy 348s might have gotten the "gas hog" tag was due to the comparison of it and the Chevy 283s that everybody was used to. I'm sure they liked the extra power and liked to use it too, but many came with (at least initially) with TurboGlides rather than Powerglides, which probably impacted fuel economy too. Plus the '58 Chevys were heavier than the '57s, which accounted for something too, I suspect. And, as has been pointed out several times, when people tried to tune the W-engine the same as a 283, it just didn't work (the efficiency of the W-engine was in the fact it did NOT need 38 degrees of total advance to make power, but about 31 degress of total ignition advance. It was a totally different engine design that was not fully understood until many years later.

Typically, Ford had only one engine family and not a "car family" or "truck family", using variations of the particular family in all places. These engines were altered for particular uses by compression ratio differneces, camshaft differences, carburetion, and possibly valve size differences. There were some vehicle model-specific engine sizes, though, through the years.

For fuel economy, the Ford FE-series 352s were not that different from other brands of engines in that general size range (from magazine tests from back then). I do know that they were some of the smooothest running engines I'd seen at that time (in the earlier 1960s) and many owners bragged of no engine problems (other than possible oil leaks--noted in some Popular Science surveys back then) at higher mileages (60K+ miles). When you look at what's inside the FE-series engines, there's LOTS of metal going round and round in there, plus that long crankshaft snout.

There were LOTs of flexibility in engine sizes in the FE-series Ford V-8s, which tended to go along carline models. Ford had the 352, Edsel had a 361. Ford had the 390, Mercury had a 410 (1966 era). The early Ford 332 quickly became the 352, just as the 406 performance motor quickly became the 427. Bore sizes and strokes (with crankshafts with a common main bearing/rod bearing size) and appropriate pistons for each combination of stroke and bore were pretty each to make happen.

In the cylinder head area, the Ford FE-series engines always looked a little different than other engines. The intake ports were taller and narrow, which can be ok as the GM LS-series motors have tall ports as did the Oldsmobile heads, BUT when you looked at cam specs, the Ford FE and Olds V-8s always had a higher valve lift than other engines. Those bigger numbers might look good, but that could well indicate a lack of port flow (this as before computerized flow benches had been invented, although flow dynamics were part of the stratified-charge combustion chamber engines under development in the later 1950s and earlier 1960s).

In looking at how things have progressd, intake manifolding of the earlier eras was more about getting the mixture from the carb base to the intake valve rather than the quality of how it got there. What was going on inside the intake manifold was just becoming to be investigated back then, but most porting and port designs were done by how good it looked rather than how well it might actually work (typically, any improvement over stock was good, but possibly not as good as things later became when a better understanding of how things needed to work became evident). And, when you consider the smaller carbuertors we had back then, those earlier manifolds were not as critical as they became in later times with larger cfm carburetors on top of everything.

On the PCV systems . . . if the engine has a "road draft tube", that's just a "crankcase ventilation system". When the PCV valve was added, that's when it became "positive crankcase ventilation system", due to the use of manifold vacuum to evacuate crankcase vapors rather than vehicle road speed. Earlier PCV systems were "open" and had a vent cap (typically the oil filler cap) on one valve cover. Later "closed" systems got air from somewhere in the air intake tract (either from the air cleaner housing (outside the filter, using something similar to the FB59 filter, or after the air had been through the air filter (from a spot on the air cleaner housing inside of the air filter's part of things or from a spacer/adapter which the air filter sat upon, as in 1969 Chevy pickups and later GM medium-duty trucks, which also had a "spark arrester" in the supply side of the system). Other systems took their intake air from the air cleaner snorkle to a filler cap via a rubber hose, but I would not classify that particularly a "closed" system as the later ones were--although any vapors out of the filler cap would be burned by the engine, one way or another, rather than being vented to the outside air.

Just some thoughts,

NTX5467

[Philippe Racicot]

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">

And back to the question for Philippe, (or whoever would like to tackle it) did early "open" PCV systems use a PCV valve? And, if so, where was it located? The reason I didn't think my '65 vintage 401s had PCV systems was I never heard of servicing any valve. </div></div>

Here's a picture of a 1965 Electra 401 engine showing the pcv valve (with the hose disconnected. It's on the passenger side valve cover near the choke cover.

Here's a 1965 Wildcat from California with a closed PCV system. Note the filter on the driver side valve cover instead of the rubber plug and the rubber hose that goes to the air cleaner snorkel. The PCV valve on this car is located at the same place on the passenger side valve cover but it's not visible on this picture as it is hidden by the air cleaner.

[55PackardGuy]

Philippe,

Thanks for the pics.

Y'know, I honestly do not believe either of the 401 engines I had in my '65 Electra had that hose and valve to the passenger side valve cover. I remember the vented cap and rubber grommet being on the driver's side cover, though.

But unlike you, I don't have any pictures of it!

NTX,

As usual, lots of good historical info. I just remember the Ford 352 being considered a "dog" by some back in the day. The 390 was considered the hot ticket when it came out, and the 289 was almost a legend. But prior to those, people really seemed to like the "Y" blocks, unconventional as they were. The 292 in particular seemed to get a lot of respect for reliability. I know the one in my old boat is just a dream. Very quick-starting, very smooth and almost stall-proof at low rpm, all of which are must-haves in a marine application for safe maneuvering. It's just never had a problem in the almost 20 years it's been in my hands.

[Philippe Racicot]

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">

But unlike you, I don't have any pictures of it!

</div></div>

Not unlike me!

These pictures aren't from my car as my Wildcat is presently stored for the cold season and the few pictures I already had from my car's engine didn't show the PCV valve. Anyway, I know it has one, I removed it once to check for possible blowby.

[Aaron65]

Guy,

Let's see pics of that old boat!

[NTX5467]

Well, Guy, the 352 had "competitive" power for the size. If you recall how the Ford big block exhaust manifolds were, it's a wonder they had any power at all, but longevity and such were a strong suit.

Agreed, the 390s were the "hot" ticket when they came out. The Police Interceptor 390 was a "special" engine with a hotter solid lifter cam. There was also a later-introduction 390 with a 600 cfm Holley and the first free-flowing cast iron exhaust manifolds and 360 horsepower.

In the middle 1980s, a friend acquired a '63 Galaxie 500/XL fastback from a sort-of-estate situation. It had belonged to a body shop guy's daughter, who had passed on early in life, but she got this 500/XL for high school. White on white, 390 4bbl, 4-speed. When some of the local young 'uns found out about it, they made their pilgrimage to see it. These were high school guys that would normally be all excited about their 5.0L Mustangs, but they were speaking of that 390 4bbl and 4-speed in hushed reverence. It was kind of amusing, but also interesting that they were several generations too young to have known about these cars first-hand, but they DID know about what it was and its significance. It was an "experience" for them just to actually see it. I know how they felt.

The 292 was a very over-designed engine, but had some interesting design features in it too. Highly reliable, once the oiling situation for the upper end was fixed or "modified". They were in most of the square cab city delivery trucks for many years after they were replaced with the 289 in cars. But, compared to the Chevy 283, not a high performance engine . . . unless it was supercharged, hehe. But, for the average buyer, the 292 and FE-series Ford engines worked just fine.

There was a guy here in town that was a retired aircraft mechanic. Originally from San Antonio, he had been in CA (Edward AFB?) and had come back to Texas to settle down and let his boys grow up. He got a local Exxon station and ran it until his normal retirement and the boys were out of school. He was one of those "Ford guys" that was really attune to Fords and what made them tick. With a small hand-held dwell tach, he could set the carb and points and such to just where they needed to be AND when he was done, that Ford V-8 (ANY Ford V-8!) would sit there and be as smooooth as it was designed to be and run correctly and efficiently. He had his own preference for brands of parts, too, which were part of the "mix". It ALL worked together to achieve excellent results. And, as you might expect, his reputation grew because of that. He could do just as well with GM or Chrysler, but you could tell his "chemistry" was "Ford". If something was flaky and nobody else could find it, he could . . . and make it work right.

And, of course, there were most probably some mechanics that could do the same for Buicks and other GM cars . . . just that I didn't see any of them locally. Not too many Buicks in town back then. This would be back in the eras of times past where craftmanship and problem-solving abilities were generally greater than what they are now, by general observation, and customer satisfaction was necessary if you were going to eat next week--especially for a "one man show".

So much for that . . .

Enjoy!

NTX5467

[michaelmis]

Re Jakes comment and the book Post war Buicks.

I have scanned the pages from this book and posted them on my website.

www.buicknet.com go to the workshop link using the blue buttons at the top.

Michael M Perth

[Guest imported_MrEarl]

Michael, hopefully everyone will not only check out that excellant article but will also take the time to peruse your site. I discovered it the other day and have bookmarked it as one of my favorites. Excellant job. I only wish I had the computer smarts and time to do the same for my love. <img src="http://forums.aaca.org/images/graemlins/laugh.gif" alt="" />

[michaelmis]

Pleased you have been able to get to my site. It is a good way of getting the info out there.

I reckon anyone who can work out a car can work out a computer. You may find one day, you will have a site for your babies.

Michael

[55PackardGuy]

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">Guy,

Let's see pics of that old boat! </div></div> Aaron, sorry none of them are scanned. I had a whole page worth over at the Trojanboats website, but they scanned them for me and later the site changed and they took away the reader's pics section. <img src="http://forums.aaca.org/images/graemlins/frown.gif" alt="" />

I'll get busy with the scanner some day and get them on a server, or just link them here.

NTX,

Have you written an automotive book yet? If not, I sure hope you do and preserve some of that wealth of knowledge.

Any luck on finding "nailhead" engineers? I know there are a lot of engineering eggheads and probably even some blockheads, but nailhead engineers must be few and far between.

[Guest windjamer]

OK guys,now you have my attention.Coments on the 401 nail head (unkind) like not to fast on the quarter lack of rpms and such realy hurt. My wife bought a 65 skylark gs in 1968,drove it till 79,parked it in the back yard till 81 and then sold it for a parts car. In 1996 my nephew purchesed a 65 gs and in the prosess found her exact same skylark in a farmers field where it had sit for near 15 years,unproteced in the mud.No there wasnt much left of it but some dreams are made of stupidty so idrug it home and spent the next 10 years on a frame off restoration.It receved a first jr. in may 06. Haveing removed,cleaned, rebult or replaced every nut bolt or screw in that puppy, I know something about it,BUT im no expert so ill just quote from the book.

[Guest windjamer]

Dont realy know why i messed up the last half of my post, but Ill try to continue . Motor trend tested the 65 skylark gs in may of 65.There specs show the 401 skylark at 0-60in7.8 sec. and standing start in the 1/4 as 16.6 sec. and a mear 86mph. Must have been a student driver. Hot Rod tested the 65 skylark gs in the same mo. and there specs. where much better. In fact a young man some of you may have heard of named Lenny Kennedy Turned the 1/4 in 13.42sec. and 104.46mph. Eat your heart out all you ford and chevys. In case you dont know I love my Buick. Hot Rod ended there article by stating when better cars are bult----- You guys know the rest. Dick <img src="http://forums.aaca.org/images/graemlins/grin.gif" alt="" /> <img src="http://forums.aaca.org/images/graemlins/grin.gif" alt="" /> <img src="http://forums.aaca.org/images/graemlins/grin.gif" alt="" /> <img src="http://forums.aaca.org/images/graemlins/cool.gif" alt="" />

[NTX5467]

As I recall, the Motor Trend Skylark was an automatic . . . a 2-speed SuperTurbine300 automatic. I suspect the one that Hot Rod tested was a 4-speed, hence the better times. ALSO, be sure to check the (very possible) differences in rear axle ratios between those two cars as the automatics did not usually have the same ratios as a 4-speed manual did.

Also, it might be good to note that Buick V-8s were NOT really designed for the same level of rpms that small block Chevy V-8s were. Buicks were about torque and smooooooth power rather than weak engines that needed really deep rear axle ratios to deliver the performance that was "legendary" back then (the Chevy smal block). Does not mean the Chevy is a bad design, just different design priorities which also reflected the body architectures/orientations of the vehicles the engines were placed in.

Until I started hanging around with some Chevy hot rodders that were around when the small block Chevy came out and heard the stories of their cars and modifications, it was THEN that I discovered that they ALL had something like 4.10 years or lower, which allowed them to get into the power band quicker and deliver the performance they were famous for. Sure did NOT have 3.36s, for example!

Also, if you look at the specs for a '61 Impala 4-dr "sport sedan" hardtop versus a similar BelAir or Biscayne, the Impala spec'd a 3.36 rear axle ratio whereas the others would have a 3.08. Was it the more economy orientation of the lower trim level cars that got them the 3.08? Not quite. Remember, in that era the top of the line model had to have the "best" motor and performance. Being that the Impala was a little heavier (more seat padding, carpeting, sound insulation, optional equipment) than the lower line cars, it needed that slightly deeper rear axle to be able to keep up with the lighter BelAirs and Biscaynes should the need arise at a stop light. Sure, you could order the 3.36 in a BelAir or Biscayne, but unless there was a special need, it usually didn't happen. Also, they had the 2-speed "fixed stator" Powerglide or the famous "budget Dynaflow" TurboGlide automatics in them back then.

I'll concur that some car magazines tended to get better performance figures than others did, but there was a lot of variables in the test procedures back then that are not all that prevalent in today's testing. BUT you also have to look past the generated numbers to the particular equipment on each of the vehicles to fully understand why the numbers turned out as they did--which most of the compilation of road tests do NOT have in them.

Now, if you read Peterson's 1965 New Car Annual, you'll find some nice comments about the particular 1965 Skylark GS 401. It talks about how the strong mid-range torque of the nailhead 401 will carry the car well into the upper ends of the speedometer in the old two-lane blacktop passing maneuvers. Torque generated from wild cam timing and small valves, it mentioned. This was also in relation to the automatic version, not the 4-speed version with deep rear axle gears, as a car like you'd find sitting on a new car lot somewhere back then, not a special-ordered purpose-driven drag racer (which was also possible with the right combination of options).

Just some thoughts,

NTX5467