ross piston/wall clearance

[1fast97gsx]

how much wall clearance are the .020 over ross pistons supposed to have? I pulled my head after 4k miles because I was pushing smoke and they seem to have quite a bit of side to side play now. I can't find the specs anymore so if somebody could post them up that would help me a lot. This is for a 2g 7 bolt with ross .020 pistons ... thanks.

 

[swordfish]

I run .004 on my ross 10.0:1 setup. Those are Marco's suggested clearances to by the way.

jeff

 

[1fast97gsx]

I run .004 on my ross 10.0:1 setup. Those are Marco's suggested clearances to by the way.

jeff

If you take a flathead and give the piston a little push from side to side do get get visible movement? I don't know if my machine shop screwed up ... but I can move all 4 pistons back and forth if I take a flathead and give them a little push. Also my crossshatching from the honing is gone after only 4000 miles which seems way too soon imo. Ideas?

 

[TSIfreek]

I am going with .0045 on mine. Piston to wall clearance depends also on the heat the engine is going to create. More boost more heat. I am also having my ring end gaps set at .019 both top and bottom also. 18 psi is what I plan on running daily so thats what I set the clearances above to and talked it over with a tech at ross . Remember you want the tightest above clearaces to control oil better and piston slap and less blow by .

 

[1fast97gsx]

I am going with .0045 on mine. Piston to wall clearance depends also on the heat the engine is going to create. More boost more heat. I am also having my ring end gaps set at .019 both top and bottom also. 18 psi is what I plan on running daily so thats what I set the clearances above to and talked it over with a tech at ross . Remember you want the tightest above clearaces to control oil better and piston slap and less blow by .

I agree with tighter being better but theres also a point in which the ring gap can be too small ( like the .019 I think ) ... check my other post "what happened to my hone" and go to the 2nd page. Someone wrote a long post about endgaps on these pistons. I'll respond with my findings on that tonight.