TransAm396

Well I guess ill be the test dummy..but I think Ill be fine. Ill be right around 600rw with a stock crank,Forged I-beams and a set of SRP pistons.(oh and a studded 2 bolt block) since this is my first turbo motor...id feel much safer playing with a 2000$ lower end(thats pretty much total) than a fully built 4,000$+ bottom end and blow it up trying to work the bugs out of my car.

stew's94z

600RWHP, Whew, that would be pushing the envelope. Everything would have to be Spot On of course but still I think the service life of the main bearings would be compromised.

Dean

TransAm396

o well..im lookin to get around 10k out of this engine.

Kevin Blown 95 TA

At 600 hp, you might have some flex with the cast crank & 2 bolt.

stew's94z

Your best chance to make this combo live is to keep the rpms down.
If you could peak at 5600-5800 it would REALLY help, but I don't know if that is possible with your setup.

TransAm396

i had the cam designed to peak at around 6-6200rpms MAX(and thats the reason I did that) I know keeping the revs down will keep it alive longer

Kevin Blown 95 TA

You're going to be about 670 at the crank...

You're going to need better everything.

TransAm396

Just like I NEEDED a dual roller chain with heads/cam but my stock chain did perfect. Just like you NEED a sumped tank/external pump for anything over 600..but someone on here is making 713rw on a single intank...Or just like an LT1 cant take over a 100 shot stock..when my first 93 with 133k miles went through about 10 bottles of 150shot with a stock pump,injectors and 93 octane..and never had a problem. I have everything I need for my goals and I think ill be fine with it. If i went by what everyone says Id get billet everything..people blow fully forged motors with 400hp...If its tuned right..it will hold. Theres someone on here making over 500rw with just forged pistons..he seems to be doing fine...

mkent

I was quoted $800 to do the 4 bolt conversion! Have you priced what it costs to do your studded 2bolt? The shop told me it wouldn't be much cheaper to have new 2bolt caps put on so I might as well do the 4bolt. I don't know what to do now... After they bore, hone, deck and balance my block/ rotating assembly they quoted me close to $1300! Its a VERY reputable shop who specializes in forced induction motors (top fuel dragsters, big blown pulling tractors, ect) but still that seems like alot of money. Maybe I'm just out of touch with the reality of cost when building a motor.

TransAm396

weird..it was 120$ for to align hone the block for the caps and 400$ to do it for 4 bolt splayed caps

ss9c1man

Im running a studded 2-bolt in my 383. The engine made 437@5800 on the dyno(flywheel). My engine builder has been building high output chevys since the 60's. He said he has never seen a cap fail. Usually a rod bolt goes before a main cap. This is coming from a guy who has run 650hp N/A I6's for thirty years with the stock blocks and 2 bolt main caps. He would also rev those engines over 7k. I think the biggest issue is in the balance of the motor. I know my SCAT rotating assembly was out of balance even though it came balanced from them. I think that is usually the problem. People just assume everything is balanced since they order it that way.

TransAm396

yeah as long as you keep the rpms down I dont see a problem. Im sure you could make over 550rw if you keep the revs down.

kline454

i have a 383 with egale 4340 crank and h beam rods and am going to spray 150-200 and turn 6800 rpm and should put down 630rwhp on a arp stud 2 bolt main, and chevy high perf siad that the to bolts with arp bolts are stronger than the 2 bolts with 4 bolt conversion not (splayed)and there many people making over 600rwhp on the 4 bolt conversion. also the shop that did the block work siad the same.

JodyJ

Do you have a part number for the caps? Also, if you don't mind, how much did you pay for them?

Thanks,

Jody J.

rskrause

I'd suggest re-thinking SRP as a choice for a boosted application. They are a decent piston for NA (I use them in my BBC) but they do not hold up well to boost. As I stated in another thread: The 2618 alloy has very little silicon in it and is preferred for a blower application. 4032 and other aluminum-silicon alloys are more brittle, so though they have some advantages (such as lower thermal expansion) for very highly stressed parts the 2618 is preferred.

The SRP pistons are 4032 alloy and are too brittle for N2O or boost.

Richard