F54 Bore Size Question

[mayolives]

I am ready to order JE forged pistons for my F54 block that will be used for a turbo project. I planned to only bore it .040 over but is there any good reason not to bore it more? I have read posts about of weak stroker motors that have been bored to large and come apart too easy and don't want the same problem. I am using a P90 head with a schneider cam that has it best power between 3000 and 6500 RPM. Also I want to stay around 8 to 1 compression ratio and will be using a good engine management system. Can anyone provide me with an experienced opinion about how much the F54 can be safely bored? Thanks for your help..........mayolives.

[Ed]

I would suggest you take the block to an experienced engine builder. They can sonic test the cylinder wall thickness and tell you exactly how much it can be bored over. They would also be able to help you select the correct piston for you to achieve the compression ratio you are seeking.

[2ManyZs]

If the cylinders can be bored .040, there's no reason to go any further unless you have to. You could probably get away with .060, but, if you do that now, and have a problem that require another boring at a later time, you'll be looking for another block instead of just boring it again.

Now sure what the limit is on the F54, but it's probably a bit more than .060, but, if you take the block to its limit, you may want to get another block as a spare just in case.

[Phred]

Ed and 2Many are correct. Because of core shift in castings, one block may be able to go .120 oversize. While another block might hit air at .120. Its best to error on the safe side, and only go .040 over, especially on a turbo where pressure and heat are greater than a N.A. engine. I have used a sonic tester on blocks, and I can assure you that there are good blocks and bad blocks. Also since you are looking for a quality job here, specify that your block be honed with a deck plate, to be certain that the rings have a nice round bore to seal up to under that extra cyl. pressure.

Phred