65SSZO6

iTrader: (4)

Wanted to input from you guys/gals on my Chevelle's engine.Currently my engine is...
2004 LQ4 6.0L LS motor from a 2500 Chevrolet truck.Stock nodular iron crankshaft turned .010/.010 new bearings Speed Pro 4.020 Hypereutetic Pistons and Plasma Moly rings.Stock camshaft and valve springs replaced with a 2004 Corvette Z06 Cam and matching spring kit.Truck intake replaced with car friendly stock LS1 intake,throttle body, fuel injectors, and fuel rail from a 2000 F-Body(Camaro/Firebird).F-Body accessory drive from 98-Up Camaro/Firebird used minus the air conditioning.Custom alternator relocation kit from SMOKINHAWK here on LS1Tech.com.Oil pan and pick up tube from Street and Performance.Stock GM 5.3L ECU and custom wiring harness (slightly)reprogrammed by owner with HPTuning software.Dougs Ceramic coated long tube headers (and motor mount adapters) into 2 1/2 exhaust with X pipe and 40 series Flowmasters.03 5.3L truck MAF.Custom intake tube with K&N filter.

200R4 trans with a 2500 RPM converter,3.73 Posi 12 Bolt rear end.

Here are my #s now 328RWHP and 337FTLBS at the rear wheels.

I was told by the tuner I should replace my stock injectors with 38gph injectors(stock injectors are max on duty cycle),and I would like to replace my LS1 intake with a LS6 and replace my stock 78mm? throttle body with a 85mm throttle body or polish mine? I do not want to change heads at all or cam just yet! I would like to see what the above changes would do and drive it for a while.Drove it from the tuner directly to the paint shop(aka paint jail!).Any help/input would be appreciated.

White_Hawk

iTrader: (3)

The LS6 intake would probably give you a few ponies. You are probably not going to go much faster with that cam though. I think the LS6 made 405 hp that year with better heads and intake.

Do you know what your compression is? A stock 6.0 truck motor has lower compression than an f-body, so if you are still at stock compression your numbers are about right. You can try milling the heads to get some of it back.

-Geoff

lilbuddy1587

iTrader: (1)

From what I've heard about, the LS truck intake manifold performs pretty well. Might want to put it back on if you have it?

65SSZO6

iTrader: (4)

My compression is 9.4-9.5 to 1 so at 6000 ft above sea level I can run 87 octane.I like the idea of lots of HP on cheap gas.If you adjust the 328RWHP with 18% drive train loss you get 400HP just like the ZO6 thru 04.Less compression but more cubes.

I was wondering if anyone had any #s for an engine similair to mine with a
LS6 intake and maybe a little larger cam?

I do not think the truck intake(aka big ugly) will fit under my hood.

69LT1Bird

iTrader: (1)

Here is what that engine made in its stock form (9.4:1), this is at the crank:

Horsepower (hp / kw @ rpm): 300 / 224 @ 4400
Torque (lb-ft / Nm @rpm): 360 / 488 @ 4000

So by using the 18% driveline loss from above, stock is:
246 RWHP
296 lb-ft of torque

So you aren't doing too bad at all. You can treat the cams and intake just like a normal LS1 engine, the FAST 90/90 setup or LS6 will work and you could look at the GM Hotcam.
The truck intakes are designed more for torque since they are for the trucks and the car version for higher RPM's and like you said, they are fuggly.

RZRSEDGE

iTrader: (21)

I could be wrong; but I don't think that the injectors should be maxxed out with that cam.

69LT1Bird

iTrader: (1)

For reference, the 2000 F car injector is 26 lb hr @58psi

I think 38lb injectors may be a bit of overkill. Make sure the injector table is set up correctly.

GMCtrk

iTrader: (23)

The LQ4's were highly underrated from the factory. Parish dyno'd his stock LQ4 at 285rwhp thru 4wd drivetrain. He estimated they put out about 350 fwhp.

To the OP, if you search the performancetrucks forum (hit the tab at the top of the screen), you'll find tons of info on the 6.0 and mods.

smok'nZ

iTrader: (160)

cut out,heads ported and milled should pick up quite a bit witha ls6 intake as well

65SSZO6

iTrader: (4)

I am starting to realize,I will have to look into a cam change and 38gph injectors at least.I would like a LS6 intake but I can not justify spending $300 for a manifold that will net me 5-10HP.Makes me think cam and spring kit + 38-42gph injectors + retune=BIG HP and TQ on 87 octane.

smok'nZ

iTrader: (160)

a ls6 will net you about 20 tuned and ported tb about 5-10

65SSZO6

iTrader: (4)

I was told by my tuner the stock injectors are at a very high duty cycle and he recommended the 38gph injectors.

I read I could use the Comp Cams XR281HR with my Yellow ZO6 springs? What kind of numbers do you think I'd get? Cam #'s are 228/230 .571 intake .573 exhaust,with the LS6 intake,bigger injectors and ported or different throttle body?

lilbuddy1587

iTrader: (1)

Don't skimp out on valve springs. Upgrade to some Comp 918's if you're planning to use that cam.

smok'nZ

iTrader: (160)

you can get 650 lift springs used for around 150

65SSZO6

iTrader: (4)

What kind of #s would I get with the LS6 intake,36gph injectors and a better throttle body?I was running way lean.

I know springs and cam changes are easy,but I just got the thing running in late June.I really do not want to change springs and cam yet.I have taken the car out 1 time to a gathering here in town.Longest drive was to the tuner shop 10 mles away.Snow is coming! I want to drive it!

hellbents10

iTrader: (10)

Typically you will see about 20hp from a ls6 intake. You will see a little more power with more fuel but not much. Going from 12.8:1 to 13.8:1 there is usually not that big of a difference unless you cannot achieve a good amount of spark advance because it is that lean.

AINT SKEERED

iTrader: (2)

I ran my stock 26 lb injectors to 420 rwhp before upgradeing to 42's. however , I had a 6spd .

You should not be maxxed out yet