[charlie66]

Originally Posted by mgarblik

The measurement Ross calls #3 is the most important to me. That is the minimum piston to bore clearance. You can only hone to a single size per cylinder. So I verify what they call #3 measurement and select hone the cylinders to get the same piston to wall on all 8. For a race build, I never finish the cylinders for the reason you see right there. If you hone for a specific clearance for each piston and cylinder, all is good. In the days with the Grocery Getter, we may have had at any different time cylinders that varied in size by .015" in the same block. As long as the clearance was right, the engine never knew the difference. The problem we had with some of the really light pistons and thin skirts was after high HP racing on N20, the skirts could collapse by as much as .010" when we would inspect them. BME and other pistons with struts and thicker skirts would hold their shape much better in these extreme conditions. Really high RPM. NA, the lighter pistons would be an advantage. I don't know for sure if this is the case, but with the thin skirts Ross likes to use, it's possible some of the variation is from tool deflection when they are finishing them. They are so thin, the cutting tool may cause different finished results based on the amount of material on the inside of the forging. If the finished skirt was thicker, there would likely be less tool deflection.

Thanks

Do you have a link for BME pistons? I would like to check them out....

[GoatRider]

www.bmeltd.com

[Half-Inch Stud]

Got my ROSS customs through SPOTTS... probably still able and ya need to contact to see if still willing.

[chiphead]

Who has the best 2618 forged piston for under $850?

[lust4speed]

I've kept quiet through several of these piston topics, but maybe it's time to have my say. I successfully used RaceTec pistons on four builds, but the fifth set of pistons were lousy - and only outdone by the arrogance of the customer service. Fortunately, or unfortunately, this was on one of my personal builds. It was a simple order for a reverse dome piston of 20cc's with a custom pin height and piston diameter. Got back an old fashion pure dished piston that measured 22cc's instead of 20cc's, pin height off by .002", and diameter .0025" larger than stated (against both our order and their supplied spec sheet). I had the machine shop send them back to RaceTec for inspection, and they returned them with a hand scribbled note that they were okay and send them back to us. No official report included, just the chicken scratching on a piece of paper. The machine shop then called RaceTec and discussed the problems, and RaceTec accused the shop of not knowing how to measure pistons at the right temperature. Just for the hell of it I took them home, stored them in the freezer, measured them hours later, and they were still way larger than their spec sheet said. Racetec owner was never available, nor was anyone else higher up their food chain. Finally gave up and just wrote them off for future orders.

I have went back to Ross and have ordered from both Butler and Kaufman, and last dozen plus piston orders have been perfect.

Screw Racetec.

[tom s]

Good to know Mike,both sets I have used were ordered by Joe Sherman and were perfect.I actually went to the shop and talked to Randy when I was building the 366 engine.He was a great help with his knowledge of the MR Rod rods I was using.Tom

[PAUL K]

Over the years I've had mistakes made by every piston manufacturer we've used...and we've used just about everyone out there. Unfortunately nowadays I see mistakes as the way of the future.

[slowbird]

Originally Posted by PAUL K

Over the years I've had mistakes made by every piston manufacturer we've used...and we've used just about everyone out there. Unfortunately nowadays I see mistakes as the way of the future.

It's just you Paul

[Half-Inch Stud]

...seems to me Mahle has bought up all the great manufactures; Carrillo rods... i lost track of the piston mfgrs.

[taff2]

I'm in the process of sonic checking a '61 389 BB code block, it's been bored to 4.120" and has a couple of thou wear,I'm hoping it can be honed out to 4.125", if it passes the sonic check then I may be able to get back out this season. Going to bolt my mains girdle on, 3/4 fill it,dry deck,reverse cool and try to get a set of custom pistons in 4.125" bore size that weigh the same as my 4.090" size Ross forgings-this will save me having to get the rotating assembly balanced again. It's going to be a struggle but my track closes at the end of this year (housing development) and I want to run a 7 there before it closes.

[PAUL K]

Originally Posted by slowbird

It's just you Paul

Lol! Might be.....I have this habit of wanting to do things the "right" way.