Trash

Concur.

BUP

iTrader: (9)

I have talked to a engine builder who mainly built these GM 6.2 L for some race prep engine for race cars as this was the only engine they could use in the class. He was the so called expert on the 6.2 's. He said it was a combination of things - weak pistons and the longer stroke but said some things on top of that is mentioned here about rods and cranks. Also balancing cranks helps as well for the internals.

He gave me his card to call him about the whole jist of it but I never called for the complete info. Also Dart is a firm believer the longer the stroke the harder it is on the pistons. I will try to find that info on youtube from them as I sit in most of their seminars when I can. They film most of their stuff for youtube when they put on seminars. FYI if anyone is interested as to what info they put out.

I totally agree about the pistons as well being weak. The 350 - 5.7 does not have problems like this with pistons and believe me I have seen a lot of lean running - poorly cooled, severely overheated, old gas ran thru the Merc & Volvo and OMC marine 350 - 5.7 that never ever dropped a piston. Now dropped a valve or cracked a valve seat or had a valve seat fall out - that's a different story, seen plenty of that going on.

Trash

I would agree but it's my understanding that some of that can be offset by changing rod length. For instance going from a 5.7 length rod to a 6.0" rod for the SBC example. This decreases piston side load, peak piston speed, and increases dwell time at TDC and BDC, which with appropriate cam timing events can optimize power/torque.

No kidding....I never even fathomed a valve seat coming out until my old motor showed me it could be done.

SB

iTrader: (1)

Exactly.

No reason to worry about a 383 pistons side load. Tune it right and Rev the ***** and keep going.

As an fyi: I don't believe in the cheap parts...so thus part of why I said above.