[65nss4spdGTO]

Originally Posted by mike leech

That's why I prefer a shorter rod than the pontiac community thinks is ideal. I'd rather have a stable piston and lower the pin a touch. Helps with rock and is like coatings when it comes to power. No differance

Another reason why Mike doesn't need coatings...

Calvin Hill
Hill Performance
708-250-7420

[Jeff Kinsler]

Originally Posted by S/st 54

Yeah but I really am looking for a specific HP. # and I know things have to be right to achieve that number..........the thing is I have already spent a healthy amount to try to achieve that # which shows I'm serious about obtaining it. Not the typical "I'm gona" that so many have said and NEVER FOLLOWED through with and do not even have a starting point let alone any kind of track results to get there feet wet...........just sayin.........I just don't want to wait 6wks to get a. "Correct " set of pistons.

loose is fast.

[fsted]

Originally Posted by Jeff Kinsler

loose is fast.

and on the edge of out of control.

[BruceWilkie]

Originally Posted by Jeff Kinsler

loose is fast.

To a point I agree Jeff... too loose doesnt work so well... same thing with women... Too tight...well, things do loosen up after awhile.

[BruceWilkie]

Whoever did the bores should have had your pistons to measure from AND used manufacturers clearance suggestions. Final hone to clearance is best.

However its possible your measuring equipment isnt calibrated or your measuring methods may need adjustment.

Your block, pistons and measuring tools should be at same temps too. Usually "normal" room temps.

PS... Diamond pistons are my preferred piston choice. If there is a Wiseco for your motor it could be another alternative.(I've used them in other apps and QC on them was very good.)

[Dave Polichena]

Diamond gets my vote too, typically they can move them pretty fast but this is the worst time of the year as everyone building, they may still get them done in time - I would call them, they have always been straight up when giving me a time frame. If you didn't have a CV head I could send a set for a 4.375 bore

[S/st 54]

Originally Posted by Dave Polichena

Diamond gets my vote.

If you didn't have a CV head I could send a set for a 4.375 bore

Yeah there's a downfall I see again........but LMAO I'm just doing what I usually do is scratch my head and try to figure out what to do cause I'll make it go down the track close or not! LOL Cause I've said it once and I'll say it again ..........hope it goes!

[S/st 54]

Ok I have to apologize..... After getting a second opinion I found out I was wrong way way wrong on my piston to wall clearance....... I never mentioned any names but those involved I apologize and I'm sorry...........

[Dragncar]

If you use block fill as one might with a factory block you need to add .002. You can hear them tick until it warms up.
I think you might want a little more ring gap too.

[cfmcnc]

Piston manufacturers listed wall clearance is their recommended" Minimun "running clearance,piston skirts are not round or straight,they are cam ground to allow for thermal expansion and thrust loads against the skirt,skirt to pin boss design is critical, some mfgs still haven't figured it out.The ring belt area is usually about .040 smaller than the skirt.Skirt Cam grinds can be manipulated to achieve best results .Bill C.