[sotxpanrider]

I had my smokey motor block bored. Motor is a 1995-2000 Chevy Vortec truck engine that I did not know the history about. Brother of mine gave it to me and I threw it into my 65 Chevy PU. Machinist at machine shop bored them out to twenty over. I am now finding out how hard it is to find twenty over pistons. I wish he would have went ahead and went to the more common thirty over. Anyway I am looking for pistons and I called Jegs. They said they can get me some hypereutectic pistons for 12.99 each. I then went to the local O'Reileys and Autozone and I was quoted 43.00 and 77.00 dollars each. Whoa, I asked what the difference was. Dude at Autozone told me that Vortec pistons are different. Hell I figured a 350 block pistons would be a 350 block piston. Is there any difference? Machinist told me he could get pistons, rings for 225.00.
I would appreciate any feedback, thanks.

panrider

[302 Z28]

That is a new wrinkle on me. I see no listings for pistons in either Jegs or Summit that specify Vortec. I say let the mechanic get em for yoVince

[coldknock]

Ask for part number H345NP20, H669P20 if you want a wee bit more compression. If they tell you anything more than $140 for the set, including tax, tell them to keep them.

A 350 is a 350 is a 350, 3.48" stroke, 5.7" rods and a 4.00" bore(stock) 1.54-1.56 pin height and a 9.025 deck height. Any piston for a 0.020" over 350 from 1968 on up will work.

If the counterman tells you different give him my number, I'll call him an idiot for you.

Larry

[sotxpanrider]

That H345NP20 is that same number Jegs gave me. But the guy could not come up with a number for rings, bummer. Would you know the part number I need?
thanks

[coldknock]

Rings are a different matter, I use Speed Pro plasma moly rings on just about everything. The part number for file fit is R9343, specify the oversize when you order them. They are a tad expensive at around $110-130 a set depending on where you get them.

Plain Sealed power moly rings are a good deal less at around $60-70 a set. The part number is E251K20 for yours. In you case they'll probably do just fine.

If you're concerned about the bore finish and ring seal, E251X20 will get you cast iron rings for around $30. They may seat a little faster/better for hone jobs that aren't quite perfect. They're fine for mild engines as long as you don't plan on using nitrous or a supercharger.

Do you know what the exact size the cylinders were finished at. The majority of shops that bore a block will finish it for 0.005" clearance using TRW pistons as a reference. You might be better off getting some forged pistons if that's the case, the cast pistons might rattle a bit until they get warm.

Larry