[GTOWAGON]

It's still at Paul's shop I have been busy and haven't had a chance to pick it up

[hpp]

http://www.egge.com/site/?d=48&dt=1&...PONTIAC&rpp=10

[Cammer-6]

that price is a little more realistic for a cast piston
Ive heard Egge casts their own so just wondering if the material is up to standards of OEM

[PMD1969]

Originally Posted by Cammer-6

Just came back from PRI and the amount of piston manufacturers was astounding.
Keep in mind that 250 and 307 Cheby pistons are close enough to use with a little attention.

Gary, Tell me more about the 307 pistons working in the 250. What needs to be done to the 307 pistons? Do they need to be milled for the valve reliefs? I thought there was something about the skirts being too long?

[Cammer-6]

Ive done it before
Ill have to dig one out and compare
Of course you wont find any pistons that will have same valve reliefs

[PMD1969]

I got an email back from Ross Pistons that said they can do the forged pistons for the 250 and the cost would $850. Holy Cripes!

[TheSilverBuick]

Originally Posted by TheSilverBuick

12bolt.com is ran by a pretty good guy and has some high quality flat top forged Ross pistons for sale, unfortuantely they only come in .040" overbore and do not have valve relief's. Of course being forged they are more money at $565 a set not terrible.

From the measurements I took you should be able to safely have valve reliefs cut into the pistons.

http://12bolt.com/250292_products/pistons

That's why I'd consider purchasing these and having a machine shop grind shallow valve relief's in it. On the low lift cam (C?), when I measured it the exhaust valve didn't stick below the deck and the intake only did by .070". I calculated the E cam would stick the intake about .108" below the deck, but figure a small .20" dimple into the thick crown of these forged pistons and you'd be good. Even less of a relief needed if using a thick Felpro gasket and/or the pistons are in the hole a bit.

I have a .035" feeler gauge there, but the distance was double that. Again, the exhaust didn't leave the chamber. This was with the 1bbl cam (C?)

[PMD1969]

Since the valve reliefs can be ground in can the diameter of the pistons be altered? I am not interested in a larger bore for this block if I don't need it. My goal is to keep it stock.

[TheSilverBuick]

Unfortunately the way he gets them cheaper is to buy them in bulk, so to minimize his cash tied up in inventory he sticks with the .040" overbore only. I know what you mean. I prefer to cut as little out of the bore as possible.

[Cammer-6]

Mark,you may be able to get by with a .010 +
Ive had several 66-9 blocks checked that had never been bored and they were .005-.007 taper.