LT1 POWR

I'm looking to build a 600+hp D1SC 383 and need some advice on what internals and heads I would need to get my compression ratio right.

Right now I can get a decent deal($3000) on the following.
383ci Forged Shortblock Eagle 4340 Crank 3.75 stroke, Eagle H Beams 5.7 with L19 bolt upgrade, SRP Forged Flat tops -5cc, Eagle Splayed 4 bolt conversion, block has been zero decked and half filled with hardner. Cam bearings installed.

Would this be a good bottom end to handle 18+psi? I'm sure I would have to get different pistons, but for the most part?


Also, what about heads? Now money is an option, but I also don't want to wish I would have gone all out to begin with.

I was thinking about getting Trickflows and having them ported by Lloyd(around $2400). I can get LE3's for $1500. And then there is also AI's.

I will be building a custom FMIC and running a meth kit if need be.

jsetzer

Some thoughts... you are in the same power range I am - as a lot of boosted people are.

You don't need extreme heads - I wouldn't spend $3k for a few NA HP - even if it equates to more boost HP - Simply because you can always make more boost. I had a set of stockers that had already been ported - spent @ $250 having the bowls opened up. We got 59.5cc out of them, not bad for a milled head.

18psi probably won't be needed. But if it is... Does a d1sc flow enough air to feed a 383 that high? (I would guess its running out of steam around there, but am not a supercharger person)

Bottom end - Theres the old saying build it right the first time. Well I am running uses srp dished pistons with no problem. Just make sure you stick to your goal. I won't be bolting on an 88 and shooting for 1k HP with my bottom end, I know better. If you haven't done any work to the block yet consider saving a few bucks on it and staying 350-355ish. Again, since its not an NA motor, making more power is as easy as more boost. There would be fewer cubes for the little blower to feed too.

Of course these are just my thoughts, others will tell you the opposite.

RealQuick

-5cc wont be enough with 64cc heads (Trickflow heads) to get a good CR for boost. Talk to a vendor like Victory racing Engines and they help match the right combo for you.

A D1SC will easily support 600rwhp... probably do it at 12-14psi.

slomarao

I would just get le1's with a little extra exhaust work. Or some out of box trickflows. Than later down the road you can send them in to be worked.

Of just pick up the TFS heads bare and throw 500 into them. Like jsetzer said, you can always run 2 more psi to make more hp. So than you would have 1400-1500 in the heads, they will still flow 280ish and will save you some coin for other areas.

If you have not already purchased the SRP's i would look into JE, Ross or diamond pistons.

LT1 POWR

If I can make the same amount of hp with fewer psi by using better flowing heads and a 383 vs. a 350/355 and lightly ported stockers for a few extra dollars to begin with and less work down the road, then why not. Then I will have room for more hp down the road just by upping the boost as long as the blower will support it.

I think 18psi on a 383 is about the limits of a D1SC.

LT1 POWR

I can get LE3's which flow 280's for $1500, or I can save a little longer and get ported TFS heads that flow 300+ for around $2400. Then I wouldn't have to go through the hassle and extra down time of having to remove the heads and have them ported later.

Why not build it right the first time?

firetird

"Right" is a matter of opinion.

You don't need 2400 dollars into heads nor a 383 to make 600rwhp. If you want to keep your options open to the possibility of making 800rwhp, then you should get the ported TFS heads and go with the 383.

BUT if you are looking for 600rwhp, a 355 with ported stockers will get you there with no problems.

LT1 POWR

Well, 600hp is just an initial obtainable goal that will satisfy my needs for now, I'm not saying I won't want more later cause lets be honest, everyone always wants more. I just want to build it so that I will be able to get more hp when I want it just by swapping pulleys rather than having to pull the heads or swap motors or something major.

I'd like to get a feel for 600 hp, see what my car can hold and turn it up a bit if possible.

Is there anything out there that will outflow ported Trickflows besides converting to SBC heads?

jsetzer

Then find a 600hp car to drive and set your goals now.

If you have that "do it right" mentality then steer clear of the srps, find something with a low silicone count. They will hold 600hp on a good tune, but a bad tune can trash them the first time they see boost - (ok any piston will go under enough detonation, but the srps are the weaker side of forged/boost pistons)

I run SRPs, but then again most tell me I did it wrong.

I think some of the bigger afr heads will flow a bit more, but at that point its a ton of money either way.

To me 2psi or $2k is a simple decision.

slomarao

I was assuming that you had some type of budget. ya as mentioned some bigger AFR"s will flow better but they will cost even more when your all said and done.
I think you will be fine with le3's. They flow plenty of air for a FI 383. I witht the guy above, find another piston. JE, Ross, Diamond. Your going to need some good slugs.

rskrause

I did a write up on this topic. This should get you started: http://www.kennedysdynotune.com/Nitr...ech%20Tips.htm

Rich

LT1 POWR

Very nice site, lots of good reading.

So aside from the pistons are all the other parts good for my goals from the 4 bolt conversion and the 1/2 fill? Is it a good deal, keep in mind everything is new?

rskrause

You don't need the exotic rod bolts. Otherwise, fine except for the pistons as mentioned. You need a dished piston to get the CR low enough anyway.

Rich