Im building a forged 370 for turbo use. Obviously the block is getting bored .030, install new cam bearings and cleaned up. Is there anything else i need to have the machine shop do while its there?

 

balance the rotating assembly since you will be getting new pistons at the very least

 

i don't have my pistons yet, but of course that will be done. Right now im just bringing them a bare block.

 

Have you talked to the machine shop? I was recommended to bring my pistons and stuff in with them because some times the precision of the pistons is off and they prefer to do the bore and hone to the spec of the piston to ensure the tightest fit. for example- your 4.030 piston could actually be 4.03001. They would want to hone accordingly.

 

no i haven't talked to them yet. I guess i'll check with them in the morning.

 

I'm building a normally aspirated 408. I took my pistons, rods, crank and cam to the machine shop. That way they could mic the pistons to bore and hone the cylinders to the correct clearance. I also bought my main, rod and cam bearings from the machine shop. That way, they could mic everything sell me the right bearing shells (I will have about 2.5 thousands on rods and mains). After the machine shop installed the cam bearings, they verified the clearance with the cam journals. When this work was completed, I took the pistons, piston pins, rings, rods, rod bearings and crank to another shop that specializes in dynamic balancing. They got the pistons and rods to be the same gram weight and did the math to set up the bob weights to balance the crank.

I had the block sonic checked, cleaned, bored/honed, mains align honed and decked the block to 9.230". As a minimum, you could just have the cylinders sonic checked, bored/honed, install cam bearings, and check main alignment and deck flatness.

What are you going to do for pistons and rods?

Steve

 

I've got a set of 6.125" Eagle H-beams and haven't decided on pistons yet. I haven't been able to find any off the shelf that will give me 9.0-9.2 compression with 72cc heads so i think i may have them made.

 

I ended up getting some custom Wiseco -18 cc pistons. You are right in that you won't find the shelf pistons you want for the CR that you're looking for with a 72 cc combustion chamber.

Steve

 

i ended up getting a -15cc pistons, i'll be right about 8.7 CR