hey guys i picked up my block from a local machine shop from getting hot tank and honed.. this machine shop did not have time to build the bottom end so i took it to a another machine shop that is local but very good. so the new machine shop is putting together the bottom end and said that the other machine shop honed it to much and my piston to cylinder wall clearance is .007 on 3 cylinders and .008 on the 4th and he said that the pistons which are ams .020 over ross piston have a .004-.006 clearance rating and he asked me if i wanted him to put my motor together even though they are i .001 to big. what are the cons i really dont want to have to buy a new set of pistons and have my block board out .030 over after this little mishap. Is the piston slap going to be bad what do you guys think.... is .001 and .002 way to loose or not really please help if it is going to be way to loose and effect my performance majorly then i wont do it but i will have to wait like 3 more months to save the money to buy new pistons and machine work. all your guys input will be appreciated a lot and sorry about some run on's i have been working for 16 hours and i am almost off.

 

if the pistons are new....maybe ams can swap them out for you.

Ask if they can measure their pistons on the shelf. maybe there is a set of pistons that are slightly bigger....

maybe ams might have a different piston make on thier shelf that measures up larger as well.

but honestly, finding a set that is big enough to put you in a decent ptw clearance is slim. especially with todays piston manufacturing accuracy....

it doesnt hurt to ask.

you may want to provide ams with the actual bore size, that way they can work backwards & see if they have anything that can fit....some pistons require a larger ptw clearance & if they are slightly larger, you maybe in luck...

btw, .007-.008 is too large....

good luck

 

.007" clearance is huge. If this is a street car, I wouldn't run it that way. Your only option is to order custom pistons from AMS (2.5 weeks) and sell your standard pistons. If this is a dedicated 1000hp drag car, you can just have the skirts coated extra thick by Swain Tech and keep the same pistons.

 

^ What he said.

 

I set one of my engines up at .065. It had fantastic ring seal its whole life of 15,000 miles. a failing alky pump took the engine out. The easiest fix here is to coat the sides of pistons. call swaintech. I am pretty sure they can spray a .002 thick coating and you are golden