Piston to cyl wall clearence?

[PorterzSupra]

Im having my block bored .40 over. I have aftermarket .40 over pistons and rings, my engine builder said he needs to know what the piston to cyl wall clearence is suppose to be. Anyone know?

 

[IJ.]

What brand pistons?

 

[boost PSSH boost]

I'm starting to think that IJ. is an automated response system...he swoops in a minute after the thread is posted.

On topic...call up the piston manufacturer, they should know..

 

[IJ.]

Damn busted!

I'm not real I'm a bot!

 

[FoolishOne]

(He might be in with SC and get an email every time someone starts a thread.)

»fo

EDIT: 'Nix that, I forgot you could subscribe to whole forums.

 

[mattjk]

be sure to tell him you don't want it to sound like a diesel.

 

[IJ.]

Nah just killing time before I go out to the shed and do some work!

 

[figgie]

Actually IJ question is VALID.

The different piston manufacture require diff cleanrance for thier pistons.

Ross wants .006 while JE want .004

need to contact the manufacture of the piston.

 

[mattjk]

who said it wasn't valid?

 

[IJ.]

Figgie: That's exactly what was in my head!

Don't know why there's a difference as they both use the same material so it might come down to the barrel of the skirts.

 

[mattjk]

slightly different mixture of alloys probably affect the expansion rates.

 

[IJ.]

Matt: Nah exact same alloy!
(I checked)

 

[mattjk]

Matt: Nah exact same alloy!
(I checked)

dang! Foiled by the BOT! :cry:

 

[IJ.]

dang! Foiled by the BOT! :cry:

Your query could not be processed at this time please try again later beep

 

[Yeahdoug]

CP wants .0035.

Take a look at how big your pistons are. I know CP has you bore/hone to 3.307 which is .040 over exactly and the pistons are actually 3.3035 in size.

 

[rakkasan]

I say 1/8th of an inch, minimum. Turbos make pistons swell......

 

[NJsupraA70]

I went .005 on my Ross pistons. The motor slapped and indeed sounded like a diesel when cold, but once warmed up it was completly quiet and slap would dissappear.

 

[suprarich]

Figgie: That's exactly what was in my head!

Don't know why there's a difference as they both use the same material so it might come down to the barrel of the skirts.

Could also be the gram weight of the pistons, diffrent amounts of material ( even if the same alloy) will expand at diffrent rates.

 

[PorterzSupra]

I went .005 on my Ross pistons. The motor slapped and indeed sounded like a diesel when cold, but once warmed up it was completly quiet and slap would dissappear.

wow thats kinda scary to think of!! :runaway:

Hey suprarich, my turbos bigger then yours!! hehe oon:

 

[suprarich]

wow thats kinda scary to think of!! :runaway:

Hey suprarich, my turbos bigger then yours!! hehe oon:

Thats my old one that shattered the shaft and sent all kinds of metal into my engine. New one will be a gt4088. Rich has turbo envy....