Phil99vette

iTrader: (11)

Just looking for some ideas. How would you guys build a 42x motor to make 600+rwhp? Here's a start:
Darton LS6 Block 4.130 Bore
4.00" Crank
Coated Skirts, Domes, Bearings, Internals

Ben R

625RWHP isn't going to be easy, or cheap. Off the top, you're looking at a 360 CFM cylinder head, plenty of compression, sheet-metal manifold, solid-roller cam/valvetrain, aluminum rods, external wet-sump or dry-sump oiling system, and a good engine builder.

The most important part is the cylinder head. PM 'Greg Good' and talk to him about LSX heads. If he posted what he can do with them he'd probably be called a liar.

Phil99vette

iTrader: (11)

Here's what I was thinkin....

Darton LS6 Block
4.130 Bore
4" stroke
12.0:1 Compression
AFR 225s with portwork/hand finishing
Coated internals
1.75" long tubes with 3" duals
LSX 90mm intake and TB
270/278 XER or new lobe cam
Solid lifters
Jesel Y2k Rockers

BlueSix

I don't think even that will be enough to get you there, I'd talk to Alan at FMS, he seems to be putting together a lot of stount solid roller set ups lately.

BlueSix

If it were me doing it I would keep the compression in the 13.5-14.0:1 range, and go bigger on the cam, something like 284/292 .800/.800. What tranny are you trying to get this power through?

Phil99vette

iTrader: (11)

You may be right. LG just made 570rwhp with a small cam, 10.x:1 compression, stock mufflers, and a few other things that were holding the car back....If it made 600rwhp I'd be happy!
Phil

RyanJ

yeah...up the compression, get some flow numbers and call Ed at Flowtech (EDC) for a custom cam. I'd go solid as well. Oh, and at least 1.875" headers.

BTL FED

iTrader: (9)

You might want to check out this thread, he made 577 rwhp through a TH400
https://ls1tech.com/forums/dynamometer-results-comparisons/244034-n-fms-408ci-dyno-video-577-rwhp.html

Ben R

Up the compression. 13.5:1 - 14:1 would be ideal.
An AFR head should be enough, but you'll be the test dummy. An LS6 head can get you there
Coated internals aren't that important.
You might think about getting a 2" longtube.
That LSX 90MM might get you there, but for $500 more you can get a good sheet-metal.
That cam makes the cam in the SAM SS look like a GM Hot-Cam. Haha.

Phil99vette

iTrader: (11)

I still want to be able to get away with pump gas....I know that with a cam that big you can run slightly more compression but 13.5:1????
Phil

11 Bravo

iTrader: (3)

I don't know, man, you may have to look at C5R heads and custom intake to get close to that goal. Maybe ported AFR 225's and a crazy solid roller setup, but who knows?

BlueSix

Are you going to build this yourself or are you willing to let a shop do it for you? I would give futral a call, they put out some crazy number's with Lee's new 408. You are going to be puching it wanting 625 rwhp and pump gas. You could probably get away with 12.0:1 without a problem if you have good gas in your area. Best of luck on your goal.

Ben R

[QUOTE=Phil99vette]I still want to be able to get away with pump gas....I know that with a cam that big you can run slightly more compression but 13.5:1????

625 RWHP on pump-gas is going to be nearly impossible. Probably not cost-effective at all.

cyphur

iTrader: (10)

Not N/A anyhow

Thats a pretty ambitious goal, 625rwhp out of a 427 N/A and have it a DD. Asking for it to use street gas is a little much. ****, I'll be happy if I could get a 383 and D1SC setup to 625 daily driven. Good luck man!!

eric01ss

iTrader: (13)

just add 250 shot there u go

MUSTANGEATER

iTrader: (10)

625 RWHP is going to be hard to do on Pump gas, 625 FWHP will be a piece o' cake. I'd talk to Schuebuck, Kaaze, or Bauer about something like this.

Phil99vette

iTrader: (11)

I guess my question would be how much is left in Lou's combo? He build a fairly mild 427 and made 570rwhp. With a bigger cam, higher flowing heads, added compression, and an exhaust more tailored to a big motor would make more rwhp just how much...
Phil

cyphur

iTrader: (10)

Got a thread with details for that new motor? I'm not acquainted w/the motor you're talkin about. Lou comes up with some crazy **** tho, he could prolly pull it off w/some SERIOUS heads and a much more aggressive cam, but not on street gas imo.

LASTLS1

iTrader: (7)

I'm working on that set up right now. I'm just waiting for the AFR 225 heads and lifters. I'll let you know the results. Should be all finished up in January. 600 rwhp or bust!

The Juggernaut

iTrader: (7)

With an automatic trans, You will need C5R heads to get that RWHP number.