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Author Topic:   2 bolt or 4
dan ferry
posted February 22, 2004 07:18 PM
here goes,id been dealing with a machine shop that builds alot of race engines for guys i race with excellent work very pricey and im thinking a very good salesman. any way after being tired of everyone knowing everything i do im gonna go elsewhere.they build engines from streetbikes to full blown drag engines. prices alot better andseems to tell it like it is like it or leave it. i asked if i should turn my 2 bolt 400 block into 4 splayed or even regular four bolt. his reply was align bore with studs and 2 bolt will be fine. whats ur opinion 7000 rpm ,zero deck with flat tops and about 60cc heads. also wondering will hyperutectics hold up i read in summit after 6000 switch to forged pistons. i have my opinion but wanna hear yours..

posted February 22, 2004 07:52 PM
WIth your engine combo I would agree with him and stay with the studded 2 bolt. If you were running higher compression and more rpm then I would jump to the splayed 4 bolt.

As for pistons, a good set of hypers should hold up fine in that combo. Of course forged would ultimately be more durable but also more money. The other thing to look at is that forged pistons are usually lighter (but not always) and that will save wear and tear on the crank and rods. Flat tops are generally pretty low in weight anyway, not like a dome which can start to get heavy. Either way a good balance job will make the most of any combo.

[This message has been edited by dirtbuster (edited February 22, 2004).]

posted February 22, 2004 08:41 PM
Sounds good, but i'd try to keep the R's down 400's dont like rpm. Maybe u have better luck than i do...

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