Overhauling a nailhead engine...sleeve or not to sleeve?

[Kosage Chavis]

I have seen a few threads on here where people have had their nailhead engines overhauled/rebuilt, but have yet to hear or see anyone bore and sleeve their nailhead blocks as part of the process.  So, this begs the question...is boring and sleeving a good idea or can it even be done on these unique engine blocks?  Thank you.

[RivNut]

I know of one guy who wet sleeved a 425 in his 63 Riviera.  He wasn't too anxious to do it but he discovered that his car is the earliest production numbered Riviera to have a 425 so he wanted to preserve it.  He drove it to our ROA meet in the Chicago area a couple of years ago.  Hasn't had any problems with it.

[SpecialEducation]

As I recall, the 322s were designed to be sleeved. Pretty sure the procedure is defined in the maintenance manual. 

[Kosage Chavis]

For the sake of performance, would you get more of a desired outcome if you sleeve or if you bore and install a bigger piston?

[RivNut]

The age old adage states "There's no replacement for displacement."

[Kosage Chavis]

22 minutes ago, RivNut said:

The age old adage states "There's no replacement for displacement."

Forgive my ignorance, but please explain this to me.  I am still learning the terminology.

[NC-car-guy]

Bore and get it bigger is what no replacement for displacement means.  But i keep hearing the after market over size pistons are crap....

Edited May 11, 2017 by wndsofchng06 (see edit history)

[Beemon]

4 minutes ago, wndsofchng06 said:

Bore and get it bigger.  But i keep hearing the after market over size pistons are crap....

They don't have the correct dome height to match the compression ratio. So if you wanted a good 322, it would probably be best to get some stock pistons and sleeve it vs boring it out.

 

This is something I'm also considering as I get closer to my tear down, so I'll be following.

[Kosage Chavis]

Okay, and that's what I was leaning towards...sleeving the engine.  

 

That leads me to the next question...why haven't manufacturers gotten the oversized pistons right?

[Beemon]

3 minutes ago, Kosage Chavis said:

That leads me to the next question...why haven't manufacturers gotten the oversized pistons right?

 

I haven't been in the game long enough to really know, but my guess is:

• It's not a Chevy
• Lower demand for parts
• The 322 changed piston and combustion chamber design almost every year of production
• The pistons are made by one supplier

[JohnD1956]

Here's some observations which may, or may not, influence your decision.

The 53-56 Buick is no rocket ship.  It is adequately powered, and moves sufficiently well for it's day and age.  Higher compression and or more displacement is not likely to change that. The bigger performance boost would most likely be found in changes to the rear axle ratio.  Even then, that performance change will be most probably "off the line" performance. In the long run, if you plan to spend more time on the highway than on the dragstrip, you stand to have better overall efficiency, in terms of miles per gallon, with the stock rear axle ratio.

 

Now, directly from my personal experience, two notes:

I once had a 2002 Ford Ranger with the 4.0 V6 and  4.11 rear axle ratio.  That off line performance was dismal and not at all what I expected. Gas mileage was horrible!

And unrelated to the above, even though the 455 in my 72 is a detuned engine, with 8.5 compression and a 2.79 rear xcle, it has absolutely no problems with off the line performance.

Both experiences only serve to point out that you do not really know how any changes one makes will ultimately impact the engine/drivetrain of any particular vehicle till you try it out.  How many times can you do something just to experiment?

 

As for sleeveing an engine, it would be my preference to only do so if it was absolutely necessary to save a block. I don't know what the process is but would expect that it would be employed mainly on engines which have already been bored out once, and where a 2nd rebore may result in thin cylinder walls, or perhaps one cylinder in an engine suffered some sort of abnormal damage and the rest of them are ok or better.  But I have no direct experience with this, so I can be totally incorrect about this activity.

[Kosage Chavis]

Aaahhh yes...the overrated Chevy.  All the way with you on the first bullet Ben.

[Beemon]

The first bullet is both a blessing and a curse.

[Kosage Chavis]

14 minutes ago, Beemon said:

The first bullet is both a blessing and a curse.

THANK YOU JESUS!!!?

[NTX5467]

As for the added displacement issue . . . when you do a .030" overbore on a Chevy 350, you get  355 cid result.  How much MORE power is 5cid going to get you?  Not MUCH, but in the racing world, that extra 5cid might be the "win" in your lane against a stock-bore competitor.  AND, it will NOT be by much!  Then factor that extra (?) engine power down by about 20% and you'll get a close idea of how much of that marginal power really gets to the pavement.

 

As for "bore" vs "sleeve", the sleeve operation was used when one cylinder wall was damaged beyond being able to clean it up with a .030" or .060" overbore.  It was a way to save the block and not have to replace the engine with a salvage yard engine of questionable history.  A less expensive way out.

 

In order to install the sleeve(s), you'll still have to overbore the cylinders to a specified size to accommodate the sleeve diameter.  There are several designs of sleeves, but I believe the normal ones have to be chilled/frozen prior to installation for the best interference fit in the cylinder block.  THEN . . . if the correct cross-hatch pattern is not on the inside of the sleeve, THAT will have to be put there, too.  Might even have to be honed to the desired final size/piston clearance?

 

As for "correct" pistons . . . what you might do is have the block "decked" on a lathe to get the correct dimension between the cylinder deck surface (what the head gasket is placed on) and the centerline of the crankshaft.  This will ensure the "blueprint spec" for compression ratio (as there's usually a little extra meat in that dimension, but not so much the intake manifold is mis-matced to the cylinder head.  Then see if somebody has some deck plates you can borrow to get the block bored/honed with.  The addition of this labor operation ensures that when the head is bolted on, which the plates bolted down simulate, the cylinder bore will maintain its roundness and aid actual compression production via better ring sealing.

 

There CAN be differences in replacement pistons, but they will ALL be "cast" rather than "forged", unless yo get into the "racing" piston selection (if such still exists for the earlier Nailheads).  One reason for the decreased selection of replacement pistons has to do with popularity and sales volume, but even in the older catalogs, there were probably fewer versions listed.  This would mean a mid-range compression ratio would be what resulted.  Something that will probably better work wit modern fuels, octane-wise.  "Premium" leaded fuel in 1957 was 97 Research Octane, as a general rule.  This might equate closely with modern 93 Pump Octane Super Unleaded.

 

It's my orientation (as others have also mentioned, just not in here) that a lower compression ratio motor with a very good/sharp tune will run better than a higher compression ratio motor for which you have to retard the timing to use available fuels (to prevent spark knock)    I'm meaning a 9.5CR vs 10.0CR "Trace rattle" on acceleration is not bad, but it's still there and better than heavy detonation. A slightly lower compression ratio motor will run better and generally cooler than the same motor in higher compression mode where the timing has to be retarded to keep it quiet under load (no rattle or clatter).  The retarded spark puts more heat into the motor and can cause overheat issues, possibly.  The plus is that it keeps the exhaust system hotter so it might make the mufflers last longer.

 

One thing about replacement pistons is that they will NOT be the exact same weight as the factory pistons, so this can involved added money for "balancing" the piston and rod combined weight with the crankshaft counterweights.

 

The other way to increase compression is to CC the heads, making the combustion chambers the minimum-spec size, which can entail surfacing the cylinder heads on a lathe.  Lathe ONLY for correct quality control and sizing!  The head and block machining operations are out of the realm of operations of some engine shops.  Many of the car magazine articles mentioned a Sunnen "power hone" to do the final honing operations, but in many cases, when the block is set-up in this fixture/machine, it's also set-up for the block decking operation plus the cylinder bore/hone operations.  Other brands, such as Rottler have these machines.  As the final hone operation is gauged by a "load meter", it takes a competent operator to come out with completely round bores for the entire height of the cylinder wall.  PLUS, as the honing operations put heat into the metal, the finish honing can't all be done at the same time.

 

You'll have to overbore the block to se the sleeves, moreso than just the normal .030" overbore (typical on many engines for rebuilding and getting to "fresh metal"), then add in the cost of the EIGHT sleeves PLUS installation operations.  LOTS of cast iron dust in the process too!  Got any fruit trees?

 

Your current pistons will probably have enough wear on the skirts that their elliptical shape has been diminished.  "Elliptical" when "cold" so that when warm, they are round.

 

In driving, it's the torque off-idle that you feel the most, so that's what matters . . . especially on a smaller displacement motor in a heavier car.  As mentioned in a prior comment, they might run good, but no "rocket ship".  Now, if you want to adapt in a THM700 or 6L80E automatic with their deep low gear ratios, then you'll need wide tires and PosiTraction to get somewhere quick.  The DynaFlow was more about smoothness than off-line tire smoke.  Not that it was not "respectable" for the middle 1950s when many other cars had 2-speed geared automatics, usually.

 

I'm not sure what the comment about all replacement pistons being "crap" means?  In the 1970s, there is an aftermarket piston manufacturer (now a part of a larger piston company) that sold pistons for normal-performance car and truck engines.  They were a good quality cast piston (with the metal inserts at the piston pin boss), but they sold for about $10.00 against a factory $60.00/each piston.  They worked just as well, although the piston weight issue applied, as the factory pistons.  They were for the "rebuilder" and "hobby person", typically, as they'd need to be fitted correctly to the cylinder bore size and such.

 

I know that we want the best and most correct parts for our vintage vehicle engines.  This is completely understandable!  But in the realm of pistons, our older engines will probably not see more than 4000rpm for any length of time, where the 2500-3000rpm range is much more probable (considering rear axle gear ratios and tire size).  In that use, the particular brand of replacement pistons worked as good as the factory items did, even in longevity.

 

Personally, I would NOT obsess about losing up to .5CR with different pistons as long as I could use less expensive fuel, the off-line torque was still good, and the engine smoothness and quietness were at least as good as "when new" . . . all of which should be doable with the correct person doing the engine machine work and assembly.  I know how to play with carb accel pump settings and add a few more degrees of base ignition timing to increase throttle response a bit.  IF you want more top end power?  Put on larger exhaust pipes and mufflers, but in a stock/incognito configuration.

 

If you need to sleeve one cylinder because of cylinder wall damage, that's one thing.  But to gouge out a whole set of cylinder walls just to re-use existing pistons and their compression ratio?  That just does NOT make financial or operational sense to me.  Save the sleeves and $$$$ for when yo really need them!

 

Sorry if I might have offended anybody with my comments,

NTX5467 . . .

 

 

Edited May 11, 2017 by NTX5467 (see edit history)

[Guest]

1 hour ago, Beemon said:

 

I haven't been in the game long enough to really know, but my guess is:

• It's not a Chevy
• Lower demand for parts
• The 322 changed piston and combustion chamber design almost every year of production
• The pistons are made by one supplier

Find a guy named Tom Telesco, he makes nailhead pistons. No other confident way to go IMHO! EAST COAST. ROLLER ROCKERS ALSO! Am I allowed to post Team Buick or V8 buick.com? Tower of Buick power parts and info, highly recommended!

[leon bee]

In my opinion, you've got to find the machine shop first. And I don't know if you've done that. Finding a guy that you like and trust is the single most important factor on this kind of stuff. I got real lucky, my man Warren's shop is about 6 miles from mine. I go ask HIM about this kind of issue.

 

And I go see him when I need the ID of something measured. OD, I can do pretty well with my ebay micrometers, etc., but on any kind of ID his figure is always different than mine.

[Kosage Chavis]

I do not plan on racing my car.  I want to do what my Dad was not able to do and pass it down to my children one day.  I just want the engine to be returned to its full strength...or at least as close as possible to full strength.

Edited May 11, 2017 by Kosage Chavis (see edit history)

[Kosage Chavis]

Anyone know a guy by the name of Matt Martin?  He rebuilds nailheads out in Cali.

Edited May 11, 2017 by Kosage Chavis (see edit history)

[NC-car-guy]

There's a Russ martin....

[avgwarhawk]

23 minutes ago, Kosage Chavis said:

Anyone know a guy by the name of Matt Martin?  He rebuilds nailheads out in Cali.

 

Matt is Russ Martins son if I'm not mistaken. 

[NC-car-guy]

35 minutes ago, Kosage Chavis said:

Anyone know a guy by the name of Matt Martin?  He rebuilds nailheads out in Cali.

Also it would cost a d*mn fortune to ship it there and back.  Have it done locally by a reputable shop.  Provide them with Russ Martin's nailhead write up that kind of points out the  do's and don't when rebuilding a nailhead.

[avgwarhawk]

I would talk with Mudbone.  He has had some trials and tribulations with his rebuild of a 322.  Parts suppliers, etc.    At the  of the day....his 322 is running well.   The manual written well enough that a rebuilder can reference it for your rebuild.     

[Guest]

There are people with these blocks that are being scrapped for lack of interest. Let me know if you need one cheap. Nailheads according to the folks at the shop I talked to, do not respond to sleeving as well as some other designs. The cylinder is bored with a "shelf" or shoulder, if you will, at the bottom, from my understanding, this is used as somewhat of a stop/guide when pressing sleeve. The casting on a nailhead cylinder extends for a bit below the point where it's full supported by cast iron surrounding it. Thinning this area while boring for sleeve is the concern they expressed. They have had this area fail and break off when pressing sleeves. Why take a chance. I remember a member Reverend, maybe, was trying hard to get the spare parts out his way when streetrodding his 55 Super. Shops here charge 110.00 a hole! Times Eight, step up with cash and I will make that will seem ridiculaslly expensive. No checks, no thousands of messages, just good parts for good prices. If you really serious, it can happen! PM, parts waiting for serious cash customers!

Edited May 11, 2017 by Guest (see edit history)

[old-tank]

No sleeves unless necessary.

Replacement pistons are durable and will serve you well, but they are a compromise and most will be lower compression after installation.

KAD36 and Mudbone have detailed 322 rebuilds.  Read and understand those threads.

I rode in Ken's car (KAD36)...it pulls like a freight train!

An engine rebuild is the last thing to do...right before you install the front clip and drive.

 

[NC-car-guy]

5 hours ago, 2carb40 said:

 I remember a member Reverend, maybe, was trying hard to get the spare parts out his way when streetrodding his 55 Super!

Its in NC with me now!  Ha ha