who would'a thought of this?

[Guest JT]

Ran across this and am amazed what these guys came up with, sure makes for a low center of g,

http://www.autohistory.org/feature_1.html

[nearchoclatetown]

JT, that's killer. I saw pics of a flathead that was run at Bonneville that was inverted flow like this. As it says, because of the shorter path for the exhaust the engine ran cooler. Never saw the upsidedown trick before.

[HarryJ]

JT ....This is the web site of the Society of Automotive Historians; it's a great organization especially for those of who are really car crazy.

[1937hd45]

Very interesting read, reminds me of the Ranger straight six aircraft engine they used in Sprint Cars. As an aircraft engine the cylinders were on the botton, but the Sprint Car guys turned it 180 degrees to have them on top like a conventional six.

[Twitch]

Makes me think of the Daimler-Benz 600 series of inverted V-12s used in Messerschmitts.

[Guest]

Twitch ~ I also think they inverted the engine in one of Grover Loening's single engine sea planes, didn't they? How about that Schneider Cup racer that Jimmy Doolittle flew? The profile looked like it.

hvs

PS: Can you invert your little operating cylinder to be in keeping with the DB engine.

[rocketraider]

Has anyone but me noticed that when you scroll down Twitch's engine speeds up?

[West Peterson]

Yes, Virginia, there is a substitute for Cubic Inches.

Re the claim, "There's no substitute for cubic inches," I'd have to disagree. I'd say that overhead cams, hemispherical combustion chambers, twin ignition and superchargers are definately substitutes for CID. Just read the history of the Duesenberg Bros, Charles Nash and Charles Greuter (Stutz engineer) and you'll find out... or, keep reading this post for a more condensed explanation.

Stutz built the most powerful engine in the mid 1920s with a 289cid powerplant, with Duesenberg almost matching its horsepower with just 260cid. Then, when Cadillac was playing with "cubic inches" with its V16 (452cid), Stutz introduced its 322cid (8-cylinder) powerplant. While it didn't match Cadillac's 175hp, it was close with a very capable and sturdy 156 horsepower. Packard's 12-cylinder was only rated 4hp higher. For Stutz, overhead cams and hemispherical combustion chambers was substitute for cubic inches.

Duesenberg, on the other hand, substituted superchargers (along with overhead cams) for cubic inches when the racing community kept lowering the maximum displacement for running races. They were able to produce as much or more horsepower with half the amount of combustion chamber capacity. In 1924, when Duesenberg won the Indy 500, no one was aware of the secret until after the race and the hood was opened.

Super large combustion chambers do not burn fuel very efficiently, which is where twin-ignition comes into play.

Sorry for the long post, but I couldn't resist the challenge.

[1937hd45]

But Harry Miller had them all beat with a blown 91CI straight eight.

[Guest De Soto Frank]

Ah, but for an engine that'll run "forever", give me a moderate-compression flathead !

Kind of like the Bugs Bunny cartoons where he keeps trying to beat Cecil the Turtle...

[West Peterson]

I believe Miller started blowing after seeing what was under the hood of that 1924 Indy winner.

[Twitch]

Cubic inches is like an arms race. To go one up on pure CID you have to trick a smaller engine out. You got a small CID engine and a large CID engine. In basically equally sized cars the large engine will be faster with more power. Ok you say your small engine gets, whatever, an OHC or DOHC and/or blower and whatnot. Ok so now it can beat the car with the larger engine. All you've done is to prove the racers' theorem since you had to resort to chicanery to produce more power. Now the large CID engine with the same mods- is it going to be less powerful than the smaller CID engine? Of course not. Whatever mod is done to a small CID engine that is matched by a large CID engine will produce more power in the big CID engine. It's primary.

A turbo-supercharged 18 cylinder 3,270 CID Centaurus V engine with methanol/water boost produced 3,220HP while a 2,179 CID turbo-supercharged Daimler-Benz 603LA V-12 methanol/water boost produced 2,300HP

A look at most historical engine evolution lines proves the statement. Our old Packards for example in a given year or few years have the same basic engine technology with the only difference being CID. Why do the 327 or 359 CID straight 8s put out more power than the 288 CID? Because there is no substitute for cubic inches!

[West Peterson]

I think you're admitting that there IS a substitute for c.i. by stating that the Big CID engine will go faster with the add-ons. By saying there is no substitute, you're trying to say that only more CID will increase power. The 322cid dohc 8-cylinder Stutz was nearly as powerful as the 452cid 16-cylinder Cadillac. What I'm saying is that there is a more efficient way to increase hp.

You're it. I quit.

(My wife sent me off to work with a bowl of soup and a fork... beat that!)

[Guest]

What we seem to have here is difference of opinion based on the fact that West is a car guy and Twitch is a piston engine airplane guy.

hvs

[Guest stude8]

The fundamental here to remember is the only way to go faster or produce more power is to BURN MORE FUEL. A big CID engine will suck it in or the small CID engine can have it blown in. That said, Jean Jennings once said at an airshow standing near an F4 Corsair "Something about the sound of 2200 PISTON horsepower stirs the soul". Stude8

[West Peterson]

What your're saying is that there's no substiture for more fuel!

By the way, I found my spoon.

[Twitch]

The saying is a true to life hot rodder theme. There was a time before computer controlled Wassitz engines when the simplest and least expensive way to get more power was to bore and stroke. These days with modern engine systems that isn't feasible. There is no substitute for cubic inches. There is a compensation or crutch only. And to be logical we have to talk apples and apples. While my 288 CID Packard straight 8 flathead produces 135HP my smaller DOHC Northstar of 278 CID produces 300HP. That's apples and oranges.

In any automotive competition class that allows CID up to a maximum of XXX we see no one using engines with less CID than their competitors. If CID wasn't paramount to be competitive what would 50 less cubes mean amongst friends? In NHRA 500CID is the maximum engine size allowed in fuel dragsters. No one uses engines with LESS displacement expecting to run 4.45 seconds at 334MPH. Suggest to a top fuel crew chief that he run a 300CID engine and then duck or you'll get that torque wrench across the teeth.

Even gassers with carburetors will run the largest displacement possible if there is an allowable CID range. If they can use 400-454CID you can bet every car will displace 454 cubes, not 401.

Aircraft, from the beginning, had the same simple formula- put the largest engine possible in the airframe- not the most techno one, streamlining notwithstanding. It's a given that the latest technology goes with it. No aero engineer would design a plane without a supercharger when the technology was such that the enemy will certainly have one too. Cubic inches ruled piston combat planes' motive power. It is simply alien for me to imagine any case why any designer/manufacturer would or ever did consider using a smaller CID engine when it might mean a loss in air superiority. 10 MPH can make a huge difference at certain times in combat.

No one ever said that more cubes is the only way to produce more power. Tongue-in-cheek- word play does not change where the original quote came from. There was a time when is was relatively easy to gain the most power for your dollar through boring and stroking. Before all the emmissions and computer crapola ended real engine rebuilds for more power for the average Joe. Guys used to pull their blocks and take them to machine shops for mods like that. It's useless to do much of that now with emissions and computer control stuff.

The whole point of smaller engines using something to compensate for the loss of CID is what makes different classes in auto competition. LSR is a good example. That's why there are so many classes. The guys like Mickey Thompson made their attempts using big blocks displacing the maximum size possible. If there was no substitute for cubic inches he and others would have tried using 4 blown/injected Corvair engines instead of Pontiacs. Heck them thar Corvair engines is aloomineeum sos they mus be light! Point is there IS a class for Corvair power and about everything else at Bonneville. Unlimited competition classes in motorsports of all kinds means the all out maximum legal CID is applied by the competitors to their machines even when smaller CID is allowed.

It's like the debate over 9mm vs .45 caliber- faster projectile vs slower but much heavier one. Situation: you have you choice of a .45 or 9mm each with 7 rounds. At 10 second intervals 7 knife-weilding assailant will enter the room and each will attempt to kill you as long as he breathes so one shot to kill or disable is paramount. So Keaneu Reeves, what do you do? What do you do?! I'd take the .45. How bout you!

[Guest]

Picking up on your 45cal vs 9mm projectile and each serving a different purpose, a trip to the Patton Museum at Ft. Knox, KY will reveal something most people do not know.

George Patton's ivory handled revolvers, not pearl as some will say, are on display there. They are generally thought to be a pair of single action 45s, but actually are one Colt single action 45 and one .357 magnum, probably S&W.

The General knew different guns served different purposes and I guess that goes for engines too.

If you think a 45 ACP slug is heavy, look at one from a Colt single action.

hvs

[West Peterson]

If you've got a rule that states a maximum displacement, then the ONLY way to get more power is using a substitute.

Whether it's a magical octane booster solution or modern technological wizardly, it's a substitute, but I'm not talking about modern wizardry.

The engineers at Stutz had no money to develop a 16, so, as I keep bringing up, with 122c.i. less than Cadillac, they accomplished almost the same power (that is, if you can believe the 75-year-old figures). I'll concede that Stutz bored and stroked as much as they possibly could while keeping the integrity of the block. The depended on the engineering finesse of twin overhead cams to get them to the same spot.

Let's discuss Apples (it's past dinner time and I'm hungry): Cadillac's unblown 8-cyl. powerplant at the time was 353c.i. -- Stutz' unblown 8 was 322. Cadillac produced 115hp while Stutz produced 156.

Packard's unblown 12 with 445.5c.i. produced 160hp. Stutz' unblown 322cid 8 produced 156hp.

The Clint Eastwood-type myth that bigger is better can be exploded with 75-year-old technology, not computer-age Wassitz technology.

By the way, I think I'd go with the lighter, faster weaponry and make my shots count. But then, I don't know nuthin' 'bout guns or using them.

[Twitch]

Yeah the SA Long Colt .45 is a monster of a slug huh? Slow moving and nasty upon impact. I read about Patton's gun somewhere. As for different calibers for different uses. Boy, that's why I got about one of every caliber. Gets expensive when you want to go shooting with all the different ammo. Strange how you collect guns over your life then look back and realize you tend towards just 2-3 favorites. Anyhow weapon choice scenario described has nothing to do with speed of projectile, sight pictures semi-auto vs revolver or anything more complicated other than 7 shots and 7 bad guys 10 feet away. 240 grain bullet or 115 grain bullet, both jacketed. Real fast bullets of small caliber go in and out of bad guys allowing them to continue their mayhem while big, heavy bullets go in and cause internal damage and don't exit.

Turbo- yep that's what I meant all along. Power is worthless if it's not reliable. Simple is better. A normally aspirated big CID engine is better since it's not got all the plumbing and complexity of turbos, electronics and whatnot that the smaller engine has in order to be equal in HP. It's under a lot less pressure for the same HP output.

West- you call it a substitute I call it a crutch to flog more power. Symantics. Fine. I do find it curious that all the technology we use today is old in concept but modern in application. The high output tech of yesteryear doesn't work exactly as it did when it was applied decades ago due to electronics and computers. Almost everything is electronically metered and controlled where the original tech was all mechanical and less efficient. While there may be nothing new under the sun in concept, the applications, chemistry and metalurgy is superior to the 1920s, 30s or whenever. That's what makes it interesting that ideas which could not be applied in days gone by are viable now since technology caught up. Not automotive stuff only but everything.

[novaman]

I'm going to throw a monkey wrench in this by bringing up NASCAR and Daytona. Where cubic inches don't make more power. The 2nd year NASCAR made them run restrictor plates everyone expect Kenny Schrader had to follow each other. Kenny could get out of line and PASS others. NASCAR's engine rule was max. 359 CID. Kenny's car was 301 CID!! The 359 CID were starving for air from the plate while the 301 had all the air it needed, therefore making more power. NASCAR then changed their engine rule to read max. 359 CID and a min CID, which I can't remember offhand.

[Guest]

Knowing Patton's reputation, the 45 Colt single action was probably as much for show as stopping power. I think it is normally a 455 grain bullet [my memory could be wrong] non jacketed lead, which packs a heck of a punch. I don't think I have ever seen a jacketed 45 long.

The .357 was no doubt included for it's metal piercing ability as well as probably greater accuracy. I own and used to fire several 45 SAs of various barrel lengths as well as a few S&W .357 magnums, and would give the overall nod to the S&W .357 magnum Combat Masterpiece I bought some 50 years ago. But boy are those 45 Colts impressive with the right cartridge belt and holster.

hvs

[Twitch]

Yeah I meant the .45 ACP with jacket. The Long Colt is always a lead ball. A friend got into pistols in a big way as a hobby some years ago and naturally began loading his own. One of his nice ones was an 1873 SA Colt clone. I still use his loads for my S & W .44 Magnum Mountain Gun in the night stand- magnum case but with less powder. Somewhere above a .44 SPecial load and less than a mganum so if I ever pop on off it won't go through my wall and the neighbor's wall!

I don't know aboyt you but the SA Colt design is the best naturally pointing pistol there is. Boy, it feels right.

My .357 is a Colt Python. Very rare these days and expensive as they were only custom order from Colt. I "stole" a new, never fired one from an ex-boss for $500 about 5-6 years ago! My oldest daughter loves .357s and is very accurate with them. That combat Masterpiece is worth keeping too. A superb piece.

I assume you have events in and around Cheyenne where they have "western days" or similarly named things with era weapon shooting and dress.

Luckily there is an swell indoor range ner me. In fact this weekend a huge gang of us are going. Last time I helped 2 new shooters get going. This time I'll have 2 more. My youngest daughter actually noticed how little I shot last time. Fun assisting newbies!

Novaman and all- I know NHRA lowered the nitro again last year. It's at 85% now and Schumacher just set speed records at Pomona last weekend still with 500CID so technology does help. I never denied that. My signoff of "there is no substitue for cubic inches" simply is the universal old hotrodders code of the West. It came from the days when guys best and least expensive way of souping was to have machine shop work done. It was cheap in the 40s-50s. There was little "bolt on" aftermarket speed equipment out there compared to now.

Normal folks didn't buy superchargers due to expense. A dual carb manifold and milled heads maybe but they knew the HP came from experienced machinists and larger displacement. Geez, the easiest way to beef up a flathead Ford was to drop a Merc crank into it or have your crank stroked. It was the one thing that could boost HP and torque at low speed! Combining overboring for power held true for 1950 Ford flatheads and it does for 350 Chevies today.

The knowlwdgeable auto engineers of the time like Roger Huntington would recommend displacement increase as theeasiest and most reliable way to gain performance. That doesn't mean a supercharger wouldn't add power fast and easy. They were expensive as they still are. The idea was to have an engine that was no only powerful but stable. Superchargers in auto use where the block is not designed for them, cause wear and stress. Like Nitrous use today. Dial in too much on the button and you're sweeping up your engine in the pooper scooper.

Remember Fordillacs and Studillacs? They were generally 49-51 or so Fords/Studes with Cadillac OHV engines swapped in. For the time, big displacement= power, in a super reliable package. No body was attempting to cobble up DOHCs for Stude 6s or direct port cylinder heads for Ford flatheads. They did what was primary. They increased dicplacement via the path of least resistance and cost.

Why are crate engines selling like they are today? Because folks still want the same thing- more power for as little money spent as possible. People are still replacing smaller engines with bigger ones. 307s make way for 350s and 302s are swapped for 351s and so on. They aren't choosing to buy turbo-superchargers for about the same price as a larger engine. It ain't happining!

If the torque of a larger displacement engine isn't immediately noticed over a smaller one by a driver today then he needs to hang up his keys and head for the wheelchair. And torque is the real force not a narrow peak HP band at 5300-5700 RPM. If anyone claims that a 183CID engine will inherently produce more torque = power than a 289CID they need to surrender their torque wrenchs forthwith.

So folksies, back in the day- and this organization seems to be all about the 'back in the day' stuff- a wise man said, "there is no substitute for cubic inches." So if anyone wants to dissect it and make word play with statements like, "yeah, but if you use nitrous there is," or "well, multi-valve heads can substitute," fine. Auto engineers and real engine builders knew you weren't done with the search for power till you increased CID. If you wanted real broad band power, reliablity, for a relatively low cost you made it bigger. That's what it meant.

PS- I find it puzzling that the most simple and honest statement about applied automotive power even needs to be defined in that it is self evident. If we were debating how to gain peak waste gate RPM relative to HP output and fuel useage it would make more sense.

[DizzyDale]

Dear Twitch,Buddy of mine with an NHRA alcohol funny car talks about how the association keeps cuttin the percentage that they can drive the blower,so he has to spin the motor higher.Just how long do you think his 525" engine is gonna last?He shifts it at 9,500 and goes through the traps at close to 10,000.diz

[Twitch]

They're at what 50% blower ratio? That'd mean a 10,000RPM engine would turn the blower at 15,000RPM. The less nitro was supposed to slow cars but the crew chiefs actually like it down from the 90% as they get less detonation and smoother running going to the 1,320 foot mark with more cylinders lit. Several speed and ET records on several tracks were set once they got all balanced out on setups. I mean the entire field of 16 qualified for Pomona at like averages in the 4.50s!!! One year ago you'd be God with times like that.

Racing organizations throughout the world are a mystery as to why they do the things they do. They've kept engine formulas forever in some cases or changed them too often. They've changed rules to handicap winners and allowed loopholes to exploit in others.

[ronbarn]

Modern technology can certainly turn smaller engines into high HP producers. But no one has remembered that the 490 CI Marmon 16 was cranking out 200 HP (compare that to your Duesies, Stutzs and Packards) in 1931, considerably more than the Cad V16.

[Matt Harwood]

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">Modern technology can certainly turn smaller engines into high HP producers. But no one has remembered that the 490 CI Marmon 16 was cranking out 200 HP (compare that to your Duesies, Stutzs and Packards) in 1931, considerably more than the Cad V16. </div></div>

That's kind of funny--although the rating systems are vastly different, my 1976 Cadillac, at 500 cubic inches, was only rated at 190 horsepower! So much for 45 years of "modern technology!"

However, the 1928 Duesenberg, with 420 cubic inches, was making 265 horsepower, and was notably faster and more powerful than just about any other car you could buy. In 1932, it went to <span style="font-weight: bold"><span style="font-style: italic">320</span></span> with the addition of a centrifugal supercharger and was untouchable in terms of real-world performance. The Marmon was only 35 HP more than the 165 horse 452 cubic inch Cadillac V16. When Packard reintroduced the "Twin Six" in 1932, I believe it was rated at 160 horsepower.

Of course, none of this is a disservice to the Marmon, which is one of my all-time favorite cars. I'd take a Marmon V16 over a Cadillac V16 or Packard V12 any day. Amazing machines that represent all that was great about the Classic Era.

[1937hd45]

I'm an auto body and paint guy, never could carry on a gearhead facts and figure conversation, but I think the cubic inch statement has been put to rest by Rick Yacoucci. With a 1000cc 440 HP streamliner he set a Bonneville LSR Record of 313.598 MPH

[nearchoclatetown]

Bob, if my math is right that 1000cc is 61 cubes. So if he had a 610 cid would it produce 4400 hp and go 3135.98 mph??? Wow , now that's cookin'!!

[ex98thdrill]

Yeah but Ron, it makes you wonder what kind of horsepower you could get out of putting an old big block with today's technology, in a new aerodynamic car.

When I look at the old police cars that had the big block police interceptor Motors that lacked the aerodynamics and technology that would fly, yet today you can take an aerodynamic car with an engine almost have its' size that can go almost as fast.

[DizzyDale]

Dear Pat,Speakin of this stuff and Daytona bein tomorrow,i believe Bill Elliott set the closed course NASCAR speed record at 230 mph at Talladega in the mid 80s.Can YOU imagine how fast they would be goin today,all the association has been doin since is tryin to figure out how to slow em down.diz

[ex98thdrill]

You're right Dale. I think most people failed to realize that Buddy Baker broke the 200 mph record in 1969 with Cotton Owens' Dodge Daytona. With the technology that has evolved since 1987 when Elliott set the record, let alone with Baker's record in 1969 it still makes me wonder where we'd be today if we had the big engines and took off the restrictor plates.

But through some reading I have found that back in 1987, Nascar didn't have a minimum tread width within their rules. What no one knew at the time was that Elliott's Coors Thunderbird was 1-1/2 inches narrower, so he had less wind resistence. The car was narrower, but not enough for his competitors to see it with the naked eye, and the rules weren't there showing the car as being illegal. As Neil Bonnett use to say "cheating isn't cheating until you get caught."

[Guest De Soto Frank]

Man, there's lots of stuff bein' kicked around here....

To hearken back to one of the comments posted near the top - about Packard simply continuing to increase the displacements in their straight-eight in quest for power....

Most other makers did the same thing...there's a huge investment in design, R&D, and tooling to consider in real-world manufacturing. When you come up with "a good design" you want to change it as little as possible, until your maximize the returns on your investment... boring and stroking an existing engine design is about the cheapest way to increase displacment and HP( if we're going with the two being synonymous). And everyone did it.

GM, Ford, Chrysler, and the independents too...

(It's all about the money... )

Sure folks knew about boosting "small displacement" engines in the '20's and '30s...but I have to wonder what the maintenance issues were with "blown" cars back then...these days, we see plenty of turbo charged cars on the used lots or junkyards with blown turbos because owners didn't follow reccommended oil change intervals, or did other things that killed their turbochargers...

I have to wonder how many supercharger drives met similar fates in Cords, Auburns, and Grahams, "back in the days before we had oil"...as one of my buddies puts it...

Also, the more "boost" you put on an engine, the more stress you're imposing on the head, pistons, rings, bottom end...ie: super-charged engines tend to "blow-up" more easily (that statement ought to draw some fire... ); most 1930's-'40s production engines were challenged enough to hold together under "normal conditions"... (that sounds a little harsh...)

Why did the supercharger disappear from American production cars for almost 15 years after 1940? Was it simply due to the WWII disruption, or were they "more trouble than they were worth" ?

If I remember correctly, when the supercharger did return on factory-produced cars, it was the belt-driven Paxton/McCulloch unit used at Studebaker-Packard, and employed on that company's MODERN OHV V-8s...they didn't bother fitting them to the hoary old Stude flathead six...

I think if one is looking for a safe, dependable source for more HP, then looking for bigger displacement is probably the answer...a bigger engine just doesn't have to work as hard to make power...

As for the '76 Caddy 500 cid that wheezed-out a mere 190 HP, that probably was from factory "de-tuning" to meet pollution regs...

I once owned a 1977 Caddy "Sedan de Barge" with a 425 cid motor; talk about a gutless-wonder...I think it was rated at less than 180 HP (less even than my stone stock '66 Impala 283: 185 HP).

I also noticed that the Caddy did not have once bit of pollution control gear on it...no air pump, maybe not even an EGR system. Just PCV and a catastrophic convertor.

Sure, we have the science and technology to build super-efficient small displacement engines, but can "we" do it cheaply enough to supply the masses and still make millions doing so ?

Does "efficiency" sell ? Is efficiency "sexy"?

I can just see the new Dodge slogan: "Yeah, it's got a 95% efficient engine!"

Again, what do you want from your engine? Super-high HP? Super-high Fuel economy? Super-long Service Life ?

Are you going to find it all in the same package?

I'm not really trying to roast anyone who posted above on this thread; I think there's always going be "apples and oranges", and many varieties of each...

[Tom Deering]

DeSoto Frank,

Memory tells me that the Kaiser was among the first of the post-war cars to have a factory installed supercharger. That had a relatively "low tech" 6 cylinder flat head engine.

Tom

[Twitch]

Hey Frank- wanna go steady? Cause your a man after my heart! That's what the phase has always meant. Exactly as you said- factories increased bore and stroke for more power as the cheapest way to gain HP and torque. An gosh, nothing provides unlimited gobs of torque like a large displacement engine.

Nobody then or now wants to drive a car with peaky power quirks. And you are correct a supercharged or turbocharged engine produces more power with greater stresses on the core which leads to diminished engine life. Every WW 2 era aero engine applying artificial boost had blatant warnings and restrictions about wear, damage and failure in the pilot's manuals.

If we go to muscle car and other American performance car websites and forums the cadre of people (mostly guys under 30) own or seek to own heavy metal. There are many, many times more that don't mess with computers and fool around with "online" anything that are dedicated to maintaning their Chevelles with 454s or whatnot. Even the dudes with rice rockets hope to one day own an older muscle car as a goal. They're just passing through the buzz box phase as a means to an end.

Oh well, yet another person understands the old tried and true phrase without attempting to apply modern explanations to an original saying.

[Guest De Soto Frank]

Tom,

I think those were in the Kaiser Darrins, weren't they ?

This is the only post-war example of an American factory-supercharged six that I'm aware of...

I think in K-F's case, they were desperate to improve the performance of their cars but couldn't or wouldn't justify the cost to produce (or purchase) a V-8 engine, which just about every other car in their price class featured by 1954 or so...

To be fair to K-F, that 226 Continental engine was a sturdy beast...but there was only so much power that could be wrung from it...I think it's last and best incarnation (performance-wise) was the OHC Tornado 230 cid engine of the '60s...now THAT with a turbo or blower would've been nasty !

( Someday, I would like to be able to play around with a super-charged Graham... )

[padgett]

Supercharging has a place: above 20,000 feet. Any lower and it is a kludge particlarly on pump gas.

For one thing the advance curve is at least three dimensional, it takes a computer and someone who understands Ricardo, not some weights and springs.

Cars of the 70s and 80s had very low hp ratings because torque also peaked very low thanks to CAFE and emissions. Some Caddys of the 70s had HP rated down at 3600 rpm

The only way to get good mpg out of a big (anything over 250 cid) engine is to keep the revs down and load high but below PE. A 3800 Buick of the late 80s is only rated at 165hp but has a very broad torque curve, near 1 lb-ft/ci to past 4000 rpm (then drops off a cliff). It can pull a full sized car around at 30+ mpg from 1300 to 1700 rpm (45-60 mph, they were designed for the 55 mph speed limit).

Besides that, some engines have much stronger bottom ends than others and these take super or turbosupercharging well. The 3800 was also one of these. Further since pump gas puts a limit on peak combustion chamber pressure (chamber design and size has a lot to do with it also) the purpose of boost is not to increase peak pressure but to increase the effective chamber size with lower compression and then fill it.

Meanwhile cars of the 20s and 30s had very low compression because gas was terrible by even today's standards (40-60 octane was typical in 1930). Even with boost it was still hardly high compression.

Just some things to think about.

Trivia: one post-war production engine ended production at 158% of its original displacement (even the 400cid version of the SBC was only 151% of 265 cid). Which ?

ps 1937 W125: 345 cid 595 hp