View Poll Results: Which Rebuild Would You Prefer?
Punch All Eight Holes 0.060 Over
10
29.41%
Keep All Seven Holes 0.030 Over with one Sleeve
24
70.59%
Voters: 34. You may not vote on this poll
Sleeve or Large Overbore
Thread Starter
Le Mans Master
Joined: May 2000
Posts: 8,729
Likes: 1,508
From: Redmond WA
Sleeve or Large Overbore
I have a 427/390 L36 engine that was bored .030 over, left to sit, and then needs a rebore AGAIN in one of the cylinders due to rust from 20 years of sitting with the valve open.
So, I can either:
a) Punch the entire thing .060 over
b) Sleeve that one hole and keep it all 0.030 over
Since I would then disclose this, would you as a buyer rather have a motor that's .060 over or that has one sleeve?
So, I can either:
a) Punch the entire thing .060 over
b) Sleeve that one hole and keep it all 0.030 over
Since I would then disclose this, would you as a buyer rather have a motor that's .060 over or that has one sleeve?
Team Owner
Joined: Sep 2002
Posts: 38,307
Likes: 2,070
From: California
With custom pistons, why not just go 40 over on all 8. The cost to sleeve would probably run you every bit what the extra cost of custom pistons would run!
I would never sleeve, unless I really wanted to save an original block for whatever reason! I would probably then sleeve all eight to be a perfectionist!
Last edited by TCracingCA; Jan 24, 2018 at 11:24 AM.
Team Owner
Joined: Sep 2002
Posts: 38,307
Likes: 2,070
From: California
It is worth it to haul it over to a machinist and have him cut in steps to see where it does clean up! Then make decisions! Usually sleeves are an automatic thought if one or more of the bores are cracked! Not knowing what block you have, on some engines 60 can be pushing things! You also have to consider the overbore for a sleeve itself! Some shops can read the wall thickness, to know if you are good! Ford 289s are notorious for having variations from block to block as to how much of a safe and practical overbore can be done! I am a Siamese bow tie block guy, and those can go out to 125 usually in a breeze!
Last edited by TCracingCA; Jan 24, 2018 at 11:37 AM.
Team Owner
Joined: Jun 2000
Posts: 38,923
Likes: 1,481
From: Southbound
Cruise-In II Veteran
Thread Starter
Le Mans Master
Joined: May 2000
Posts: 8,729
Likes: 1,508
From: Redmond WA
They're going to sonic-check the block and get back to me. My thinking was that if I know the block is good for 100 or 120, then going 060 won't be a big deal. If it's tight, then sleeving it might be better.
For the purposes of this thread though I was more concerned with buyer perception than the technical details... just how do people "feel" about a sleeve vs a large overbore.
For the purposes of this thread though I was more concerned with buyer perception than the technical details... just how do people "feel" about a sleeve vs a large overbore.
Pro
Joined: Nov 2017
Posts: 587
Likes: 49
From: Belgium
I'd choose whatever 's the cheapest, then again, I'm only a poor student ;-)
If funds were no problem, +60 really is the way I'd go, just because I know I'd want the 5 extra bhp from those CC's ( maybe more, no idea tbh).
If funds were no problem, +60 really is the way I'd go, just because I know I'd want the 5 extra bhp from those CC's ( maybe more, no idea tbh).
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Le Mans Master
Joined: Oct 2002
Posts: 7,098
Likes: 378
From: Las Vegas - Just stop perpetuating myths please.
Sleeving is a great way to save a valuable block or repair just 1or 2 cylinders. But it's always going to be cheaper to just bore the block if you have to buy a full set of pistons anyways. Before strong aftermarket blocks were available some owners/racers would sleeve all the cylinders but at $200 a sleeve that's now an expensive block and used standard bore blocks would be much cheaper.
Unless you have specific concerns let the cost of sleeving be your guide.
Unless you have specific concerns let the cost of sleeving be your guide.
Thread Starter
Le Mans Master
Joined: May 2000
Posts: 8,729
Likes: 1,508
From: Redmond WA
The only other thing is that we don't know if torque plates were used when they bored it. I have the bill for that rebuild and the overbore charge was $100 no mention of plates, so I assume not.
Am I correct in assuming that if a block has been bored .030 without plates, it cannot be bored 0.030 WITH plates? You'd have to go larger. So that is perhaps an argument for the overbore approach.
Or I could say "Factory didn't use torque plates either" and still sleeve it.
Will let you know what the sonic checking revealed when I hear back.
Am I correct in assuming that if a block has been bored .030 without plates, it cannot be bored 0.030 WITH plates? You'd have to go larger. So that is perhaps an argument for the overbore approach.
Or I could say "Factory didn't use torque plates either" and still sleeve it.
Will let you know what the sonic checking revealed when I hear back.
Thread Starter
Le Mans Master
Joined: May 2000
Posts: 8,729
Likes: 1,508
From: Redmond WA
Looks like it's going to need a sleeve because the rust might not even clean up at 0.060.
I now have a final choice to make:
- Sleeve bad hole, go .040 over with new pistons, balance, deck, and torque-plate hone
or
- Sleeve bad hole, stay 0.030 with existing pistons, balance, assemble
In other words, if I want to torque plate hone the motor, I've got to change pistons. I'm not that passionate about it but the notion of -not- using torque plates seems to really bother my builder.
So, if I can find a good 0.040 piston with the right dome (suggestions welcome) I think that's where we're headed.
I now have a final choice to make:
- Sleeve bad hole, go .040 over with new pistons, balance, deck, and torque-plate hone
or
- Sleeve bad hole, stay 0.030 with existing pistons, balance, assemble
In other words, if I want to torque plate hone the motor, I've got to change pistons. I'm not that passionate about it but the notion of -not- using torque plates seems to really bother my builder.
So, if I can find a good 0.040 piston with the right dome (suggestions welcome) I think that's where we're headed.
Le Mans Master
Joined: Dec 2006
Posts: 8,837
Likes: 1,028
Looks like it's going to need a sleeve because the rust might not even clean up at 0.060.
I now have a final choice to make:
- Sleeve bad hole, go .040 over with new pistons, balance, deck, and torque-plate hone
or
- Sleeve bad hole, stay 0.030 with existing pistons, balance, assemble
In other words, if I want to torque plate hone the motor, I've got to change pistons. I'm not that passionate about it but the notion of -not- using torque plates seems to really bother my builder.
So, if I can find a good 0.040 piston with the right dome (suggestions welcome) I think that's where we're headed.
I now have a final choice to make:
- Sleeve bad hole, go .040 over with new pistons, balance, deck, and torque-plate hone
or
- Sleeve bad hole, stay 0.030 with existing pistons, balance, assemble
In other words, if I want to torque plate hone the motor, I've got to change pistons. I'm not that passionate about it but the notion of -not- using torque plates seems to really bother my builder.
So, if I can find a good 0.040 piston with the right dome (suggestions welcome) I think that's where we're headed.
Thread Starter
Le Mans Master
Joined: May 2000
Posts: 8,729
Likes: 1,508
From: Redmond WA
He'll let me decide, but his suggestion is 0.040 in all holes with a sleeve in the bad one. Makes sense to me, the only downside is we're doing new pistons and an overbore really just to get torque plates. That's where we're not really on the same page.
My thinking is Tonawanda built a million of them without torque plates, but I'm not going to push him into doing what he feels is a "substandard" job, because I want his A game on everything else.
My thinking is Tonawanda built a million of them without torque plates, but I'm not going to push him into doing what he feels is a "substandard" job, because I want his A game on everything else.
Race Director
Joined: Mar 2016
Posts: 14,332
Likes: 8,139
From: Napa Valley California
With all the machining costs why not just purchase a new GM 454 4 bolt block, $1300.00 from Summit Racing.
Put in standard 454 pistons and have a new block, pistons, and rings. That way you have no sleeved cylinders and 454 cu in, which will increase the value of you car.
There are plenty of used 454's on craigslist and ebay.
Put in standard 454 pistons and have a new block, pistons, and rings. That way you have no sleeved cylinders and 454 cu in, which will increase the value of you car.
There are plenty of used 454's on craigslist and ebay.
Le Mans Master
Joined: Oct 2007
Posts: 7,445
Likes: 971
From: Tennessee/Rhode Island
He'll let me decide, but his suggestion is 0.040 in all holes with a sleeve in the bad one. Makes sense to me, the only downside is we're doing new pistons and an overbore really just to get torque plates. That's where we're not really on the same page.
My thinking is Tonawanda built a million of them without torque plates, but I'm not going to push him into doing what he feels is a "substandard" job, because I want his A game on everything else.
My thinking is Tonawanda built a million of them without torque plates, but I'm not going to push him into doing what he feels is a "substandard" job, because I want his A game on everything else.
Burning Brakes
Joined: Jan 2007
Posts: 968
Likes: 122
From: Lighthouse Point FL
Are you trying to save a numbers matching block?
If not, then as a buyer, I’d rather have a new shortblock than an engine that’s been rebuilt a couple of times...
If not, then as a buyer, I’d rather have a new shortblock than an engine that’s been rebuilt a couple of times...
Last edited by maj75; Feb 1, 2018 at 09:02 PM.