SPANKY LS1

iTrader: (24)

Well, got the car tuned and dynoed today. The numbers are 410.8 HP ad 373.7 TQ. The modifications are listed below, the car was dynoed on 28" tall drag radials, and through a 4.30 geared 12 bolt. You tell me, are they low, or are they ok, in your opinion. What next? How do I get to the 430-440 RWHP numbers like everyone else, does my 4.30 geared 12 bolt make that impossible, or is it something else? Thanks, Shawn

2002 Z28, M6, Sebring Silver, Graphite cloth interior. Loaded. Mint condition, 3039 miles on it .

TEA S2 5.7 heads, Ferrea 2.02 1.55 valves, milled .005
Comp Cams 987 dual springs (1.55" dia), Titanium retainers
TR 230/224 cam 111ls, TR 7.4 chromoly pushrods
Fast Toys Ram air
ASP pulley
Hooker LTs, coated by Jet Hot
Hooker ORP, coated ny Jet Hot
Hooker 3" catback, dual 3" chrome tips
MMS ported/epoxied TB
SLP 85mm MAF
MTI carbon fiber lid, K+N filter
Hypertech 160* thermostat, Pro 5.0 shifter, Hurst leather handle
SLP bellows, SLP fan switch, Autotap
Hypertech CAGS
O2 simms
BMR boxed SFCs, powder coated silver
BMR LCA relocation brackets
Billingsley Racing "Race" LCAs
Billingsley Racing "Race" PHB
Moser 12 bolt, HD Eaton posi, 33 spline, 4.30 gear
Weld Draglites 15x8
Nitto 555 DR 275/60/15

Ragtop 99

iTrader: (7)

If you want 430 RWHP on the dyno, you need 2 changes:

1) Reinstall your factory 10 bolt with 3.42 gears
2) Put your factory goodyear tires back on.

If you want to be fast, go to the track with your current set-up and let her rip!

John B

iTrader: (10)

First off did you run a wide band O2? Do you know what your timing is?

Your exhaust system sucks. Get a true dual 3" or at least a 4" single mufflex.

SPANKY LS1

iTrader: (24)

Wide band O2 says right at 13 to 1, from 3000-6600, then dropped to ~12.5 to 1. Timing, he didn't give me that information, I can ATAP and see.

I thought the Hooker catback was a good flowing catback? I remember reading someone only gained 4rwhp on a H/C car going from that catback to a cutout?

GODUCKS

Most cars don't see 430rwhp-440rwhp, you # looks good to me... You gotta remember only a few cars are getting those numbers, and they get all the attention when posted... When in fact most cars see numbers like yours...

GODUCKS

Those 440rwhp cars, also have more compression, ls6 heads, and more cam, and bigger exhaust systems...For your mods you # look reall good to me throught a big rear

cantdrv65

iTrader: (3)

The hooker is an excellent flowing catback. Supposedly, the reverse split cam is for open exhaust. Running through the exhaust you'd probably make more power with a larger traditional split. POSSIBLY... Personally I think your numbers are absolutely great!!! Especially with only 3000 miles on the clock. It'll probably get stronger with a little more break in. Should be a real beast at the track. Congrats!

SPANKY LS1

iTrader: (24)

Here are a couple of examples of similarly modded cars.

***2002 Onyx Black SS M6
TEA Stage 2 5.3L heads, F1 cam, Moser 9 w/ custom center, 4.30 gears, SPEC Stage 5, Random Tech TA, BMR adj LCAs, Eradispeeds, Kooks LTs, Shaner TB, ASP pulley, Pro 5.0, SLP SFCs, 27 x 11.5 Hoosier QTPs, Custom Tuning
449rwhp, 399rwtq


***2001 Z28...
TEA Stg 2 Heads, TR 230/224 cam, Grott headers, Shaner Stg 2 TB, FTRA, True Dual Exhaust w/ X-Pipe, MTI lid, ASP pullies, moser 12 bolt w/ 4.11s, competition Hurst shifter, carbon fiber d/s, Mcleod Single Disk/Alum. Flywheel
440rwhp 401rwtq

As you can see, I'm down ~30 HP and 30 TQ from these cars.

Again, I'm not disappointed, just curious if I'm leaving anything on the table, or if my numbers are what I should expect. I can tell you one thing, on drag radials and 4.30 gears, he car is a BEAST to drive.

Fireball

iTrader: (21)

the first car you listed is inherently higher compression due to the 5.3L heads. The second car has some help with the true duals and ALUMINUM FLYWHEEL

Also remember some dynos read higher than others...I've seen +/- 20 hp swings on local dynos here. The dyno is a tuning tool...its not an absolute

FWIW...when I pulled 444 RWHP, I had a steel flywheel, GSCs on stock TA rims a custom steel 3.5" driveshaft and 4.71 gears. But I think the extra exhaust duration and compression I run boosts overall torque and power... (I have 5.3L heads milled .040 and a 232/232 112 camshaft)

verbs

Here is why....

I'm at 10.8:1 compression, you are close to stock.

I have an aluminum flywheel and a carbon fiber driveshaft.

I have crank and alt pullies..I'm not sure if you have both or not. I also added some timing.

Maybe you are getting knock retard? Have you autotapped? Have you changed your plugs or tested coilpacks/wires? There are too many possiblities to even guess right now.

SPANKY LS1

iTrader: (24)

Oh, you again

What is stock compression 10.1 to 1? My heads were milled .005, so I probably have 10.2 to 1.

I have crank and alternator pulleys, also.

I will autotap today, to check timing and knock retard. I installed new plugs (AC Delco, I believe) ~350 miles ago. (At time of head and cam install)

Pro Stock John

iTrader: (34)

Probably losing 10-15rwhp from the rearend and the taller tires. If you really want the bigger numbers put 26" stock tires back on in back, get a lighter flywheel and a CF driveshaft.

Leave the A/F alone it's fine.

GODUCKS

Look for a dyno in your area that puts out the numbers too

SPANKY LS1

iTrader: (24)

Well, just went out and autotapped it, heres what I got:

RPM Ign timing advance, degrees

FIRST RUN (First and second gear)
2132 39
2261 34.5
2462 31.5
2627 30
2922 30.5
3147 31
3434 27.5
3736 27
4079 25.5
4401 25
4719 25
5069 25.5
Stayed 25-25.5 until 6700rpm

shift to second

5238 22
5373 23.5
5559 24

-------------------------------


Second Run (second gear only), ign timing stayed 23-24 from 3142rpm until 6378rpm (Let off)


There is no knock retard to be found, are these timing numbers low, or are they on par? TIA, Shawn

Pro Stock John

iTrader: (34)

24-27 degrees of timing is fine, you are losing rwhp from the rearend and from the taller tire, not to mention the little things you can change... A bit more timing might be worth 3-5rwhp.

Slowhawk

iTrader: (12)

Don't fall into the # game.Cars and Dyno's are different.Some read higher than others.
For your info I lost 15hp when I installed the 12 bolt with 3.73 gears and lost another 5hp with the addition of the steel driveshaft.I have 2 shops around me and 1 reads 20hp more than the other.

SPANKY LS1

iTrader: (24)

Easy for you to say, you have 412 rwhp

H82BBad

I think those are good numbers considering your compression.

Slowhawk

iTrader: (12)

But look at my sig
I'm running 11.3-1 compression and spent hours dyno tuning to get the most
The dyno I use I know is not calibrated the way it should be,but I use it as a tuning tool.

Slowhawk

iTrader: (12)

I also run 28 degree's of timing from 2400rpm to 6600 rpm.That could be your problem,try more timing in the higher rpms.