Grr

iTrader: (2)

Something definitely wrong here, I ran 120mph with my stock bottom end 346, ported 243s and eps 238/246. Not to mention with a stock ls1 intake and 1.75" headers and 3" catback

Your car should be trapping 125+ all day

James@ShorTuning

Yeah 440rwhp on mine in a 35-3600lb car is capable of 125-126mph trap speeds. My auto heads cam formula made 418 and trapped 123.8mph at 3570 raceweight

KingPin1094

iTrader: (12)

Im probably at 3850, but i just saw a guy (pwrdbyls1) on youtube run 10.97 at 126 with damn near the exact setup as me.

tsnow678

iTrader: (3)

I think the compression is hurting you the most. I have the following engine:


408ci cast iron block
Forged Manley crank
Callies 6.125" h-beam rods
Manley flattops
stock L92 heads w/patriot .660" springs. With the flatops and stock heads yields between 11.25-11.5:1
Comp custom cam 22x/24x @.050" .631"/.657" with stock rockers 115LSA
stock LS3 intake with factory injectors
96mm PP throttle body
1-7/8" Dynatech headers
3.42 gears

mine dyno'd at 471rwhp/450lbs @ 94 degrees and 20% humidity on a DynoJet.

KingPin1094

iTrader: (12)

The temperature shouldnt matter, because there should be an SAE correction. Also thats on a dynojet. Id probably be close to 500whp on a dynojet.

Also i took the car back up there with increased compression and a FAST 102mm intake and so far have made 460whp but the car was hot and sucking oil through the catch can so i took it home cleaned it and fixed the catch can, and im heading back up saturday

tsnow678

iTrader: (3)

Good luck on your next pull!

I don't get too hung up on the glory numbers of a dyno pull as they are only a baseline for future improvements. At least now you know where you are at and can judge what actually improved your horsepower/torque from this point forward.

Toms River that's cool! My dad used to drag race at Atco just up the road.

george g

iTrader: (12)

I made 506/468 with my 408 with ls3 heads, so ls3 heads on a 4.030 do work fine.I would have made more but the valve springs I had at the time wouldn't close the valves over 5700 rpm.This is in a GTO with has more parasitic loss than an f-body.

KingPin1094

iTrader: (12)

Made 462.5WHP and 429.9WTQ. went to 11.5:1 compression and added a FAST LSXR intake with minor port work. The car pulled to about 5950rpm instead of the 5800 it did before. I also started gaining power from about 3500-4000 rpm. All in all im very happy with how the car runs. Cant wait to get it to the track!

rkdc5z06

nice ##s

Jwilliams04

Raised the Comp and retune. I think there is a lot missing in your setup. I have a 402 10.5 comp with 502 rwhp.

KingPin1094

iTrader: (12)

On what dyno though? I would probably dyno 520whp on a dynojet

kdcobrar

I just dynoed my car today and it made 496rwhp through a th400/4000 stall and an 8.8 in a foxbody mustang. Here is what I have...
Iron block 408 11.5-1
K1 crank and rods with wiseco -3cc pistons
Comp cam 247/255 .624/.624
Very mildy ported l92's, ls3 rockers with comp trunion upgrade
Victor Jr carb intake
Pro systems 1000hp

L92 fox

iTrader: (2)

Ls3 heads work just fine on my 408.
My 408 with milled and ported scroggin dickey cnc'd ls3 heads, stock ls3 intake and 90mm throttle body, tsp giant cam, 13 to 1 compression on 93 with 1 3/4 headers and a slp 2otl made 550/510 through a t56 and 7.5.

KingPin1094

iTrader: (12)

Yea im thinking about raising the compression some more and putting a larger cam (24x/25x) sometime in the future. Maybe get some small bore cnc ls3 heads. and maybe some spray in the future

quik01ss

iTrader: (24)

Now you're talking ^^^

DietCoke

iTrader: (18)

Engine peaks at 5700. That should be the end of discussion on the crappy numbers and results. Put a proper cam on it and turn it 13-1800 more rpms, and it will go faster.

KingPin1094

iTrader: (12)

peaks at 6 now. But yea i agree, in about 2 years im going to have to replace my springs and when i do that i think im gonna up the cam size.

ajrothm

People here can either not read or comprehend that it was dynoed on a Mustang Dyno... That's easily 10% lower reading then most DynoJets.. This car is easily 500rwhp on a DJ.. Pretty much in the ball park of where it should be. Although I agree with the comments on the early peak power... Maybe a valve spring issue or something.... Definitely should peak higher/which would likely make a bit more power.

I'd be looking at valve train stuff and maybe a cam swap down the road.

Get it on the track and see what it traps.. Then you'll really see where you're at...

I see tons of these "killer" 525hp NA setups that trap 122 mph at 3500lbs..

L92 fox

iTrader: (2)

I haven't been to the track with it, but my car is with in a car lenght against a 128-130 trap car. And I can't drive my car worth a ****.

Mikey 97Z M6

iTrader: (37)

I'd be putting a degree wheel on it and see if the valve events are where they should be. Something is def not right with your setup.

My little 370 put down 490rwhp on a Mustang dyno with self-ported L92 heads and a L76 plastic intake, 90mm tb and TSP 1-7/8 headers. Also had a 387 with the same heads/intake and a 236/236 .585/585 112lsa cam, never had that one on the dyno but it trapped 126mph all day long.

Mike