bore questions???

[alliedmike]

Hey guys i have an 84 block. have been having problems with blow by past the cylinders during a leak down test. so i pulled the engine apart and found that someone previously has been in this motor and has bored the cylinders out 30 over allready. they accually bored it a little more than 30 over and the hatch marks from honing are still there. so they apparently did not know what they were doing if the final bore is more than 30 anyhow my question is to clean this up so it is good for new pistons can i safely bore out to 40 over? thanks for the input

Mike

 

[charlief1]

Make sure of the bore size before you do anything else. You can have custom pistons made to any size so you may not need to do much more than a hone.

 

[ttaowner]

got a 84 gn that i am parting out.block is standard .sell you the block for $100 bore it out and reuse your pistons.i am in connecticut

 

[bison]

Hey guys i have an 84 block. have been having problems with blow by past the cylinders during a leak down test. so i pulled the engine apart and found that someone previously has been in this motor and has bored the cylinders out 30 over allready. they accually bored it a little more than 30 over and the hatch marks from honing are still there. so they apparently did not know what they were doing if the final bore is more than 30 anyhow my question is to clean this up so it is good for new pistons can i safely bore out to 40 over? thanks for the input

Mike

You dont bore the block then order pistons. You order pistons then bore it and finish hone it to fit the pistons. Its cheaper to start with another block hen get pistons.

 

[charlief1]

You dont bore the block then order pistons. You order pistons then bore it and finish hone it to fit the pistons. Its cheaper to start with another block then get pistons.

Good point Brian but since it's already bored .030 over maybe(?), he could just make sure of the size and see if he can have a set of pistons made for about what he'd pay for new pistons with a bore and hone. I'm sure you may not agree with me but he's already got a fresh bored block and it would be roughly about the same cost.:smile:

 

[alliedmike]

Thanks guys for all the input. the thing is i am restoring the entire car top to bottom. so i would like to keep the matching block to the car if at all possible . i know they sell .040 pistons i was just curious if anyone has had any problems or luck going the route of buying pistons that are .040 and boring out and going that route. it sucks that someone has allready got it up to .030 and did it wrong......thanks guys


Mike

 

[bison]

Thanks guys for all the input. the thing is i am restoring the entire car top to bottom. so i would like to keep the matching block to the car if at all possible . i know they sell .040 pistons i was just curious if anyone has had any problems or luck going the route of buying pistons that are .040 and boring out and going that route. it sucks that someone has allready got it up to .030 and did it wrong......thanks guys


Mike

Id go .040 but i wouldnt use it for sub 10 sec power without a sonic test

 

[alliedmike]

Id go .040 but i wouldnt use it for sub 10 sec power without a sonic test

ok sounds good...i mean this is only a hot air...just adding turmomotion inter cooler and alky thats about it i would imagine i would be allright with that ??