help me decided, .030 or .060 over?

[big83chevy4x4]

i need to bore my 454.
should i bore it .030 over or go .060 over?

also the pistons im getting come with either a 1/16" ring or a 5/64" ring.
should i go with a thinner ring or thicker ring. what are the pros and cons of both.
im ordering them in a few hours, help me decide.

 

[Hogback Fabrication]

If your block is in good enough shape that you only need to bore it .030", just do that. The more you overbore an engine the weaker it gets and the more potential overheating problems you can have.

 

[4X4HIGH]

If you go .060" then you have no rebuilds left in that block, with that being said bore it .030". The thicker ring set would be best for longevity reasons, the thinner ring set would be slightly better from a performance stand point.

 

[6.2Blazer]

The only reason you need to bore it is to clean up the cylinder walls from any scratches/gouges it got from wear and tear. With that said you should bore it the minimum amount needed to get rid of the wear.

 

[longbedder]

.030" over
get it torque plate honed
Thick rings (assuming this is an offroad/dd mo-chine)

 

[big83chevy4x4]

ok, i ordered the .030 over 5/64" rings pistons. i was leaning toward the .030 1/16" pisons, but id rather have the longetivity.

thanks

 

[BadBob]

If you go .060" then you have no rebuilds left in that block

It depends, some of those blocks had some seriously beefy cylinders, and can go more than 0.100 over, but you'd need to have it UT checked first.

 

[76zimmer]

It depends, some of those blocks had some seriously beefy cylinders, and can go more than 0.100 over, but you'd need to have it UT checked first.

Ditto that, rumors abound about going .125, but again Ultrasound testing should be done first.

 

[4X4HIGH]

It depends, some of those blocks had some seriously beefy cylinders, and can go more than 0.100 over, but you'd need to have it UT checked first.

You are about half correct. The early 70's 454 did had some with thick cylinder walls but all of the later blocks are then and .060" they start having heating issues. Most of the early 454's have been long gone to the drag racer and just about every 454 people find today are the later blocks from the late 70's on which are thin.

The only way to tell for sure though is to have the block sonic tested as you've said.

 

[Bow-Tie-Boy]

The only reason you need to bore it is to clean up the cylinder walls from any scratches/gouges it got from wear and tear. With that said you should bore it the minimum amount needed to get rid of the wear.

X2.

 

[Leper]

X2.

x3.

 

[76zimmer]

x3.

= 6