View Full Version : Help with modded ls6


Hillbilly25
09-01-2012, 02:26 PM
I recently bought my first sports car. Its a 01 z28 with some mods, here is the list. Engine is a forged 347ci ls6 built by late model engines in houston, texas speed ported 243 heads with dual valve springs and 60cc chambers. Patrick g spec'ed cam 236/242 on a 110 lsa. Callies forged rods and crank, arp 2000 rod and main bolts, arp head studs, wiseco -2cc dish pistons. Fully balanced and blueprinted. F.A.S.T fuel rails, full braided lines from tank to rails, 42cc racetronix injector, racetronic in tank fuel pump kit(walbro 255). Pacesetter headers, TSP y pipe with true merge and magnaflow catback. Tranny is a t56 built by 6 speed inc. The top rings can handle a 250little shot of nitrous but has never been hooked to a bottle. The car dyno'ed 430 rwhp. I have done some research about all of the parts but it seems it should have nade more power. Some people claim to come close to these numbers with smaller mods. What could i do to add more power? Throttle body? MAF? intake? As i have no clue what parts would match what i already have. Any help would be greatly appreciated. Thanks. Oh yeah im pretty sure it still has a stock ls6 intake

conan
09-01-2012, 05:12 PM
Don't get to caught up on dyno numbers... Different dynos, colder weather, lower elevation, lower humidity all can change numbers quick.

You have a forged bottom end... throw a 150-200 shot at it.

Hillbilly25
09-01-2012, 06:39 PM
I thought about the elevation. I bought the car down south and brought it to northwest indiana. Should i get it re tuned?

ULTIMATEORANGESS
09-01-2012, 07:21 PM
I thought about the elevation. I bought the car down south and brought it to northwest indiana. Should i get it re tuned?

does it run smoothly? meaning is drive ability a long with power seem fine?

Hillbilly25
09-02-2012, 10:52 AM
The only thing i have really noticed is when i come to a stop it idles down alot lower than i think it should. It usually idles around 900 rpm but lately it drops to the 400-500 range and i have to hurry and hit the gas so it dont die.

ULTIMATEORANGESS
09-02-2012, 11:36 AM
The only thing i have really noticed is when i come to a stop it idles down alot lower than i think it should. It usually idles around 900 rpm but lately it drops to the 400-500 range and i have to hurry and hit the gas so it dont die.

yea, i needed a few driveability adjustments once my setup was installed.

garygnu
09-02-2012, 12:40 PM
sounds like a great a great car.maybe consider a fast intake with a bigger TB.for the low idle problem maybe clean the MAF sensor ,or check the TPS sensor.what air cleaner dose it have ?seeing the heads were milled ,maybe you should measure the push rods to make sure the push rods are the correct length for proper lifter preload.

Jovozx12
09-27-2012, 10:21 PM
What intake are you running?

punisherls6
09-28-2012, 01:15 AM
I have a 00 ss with a ls6 swap i have slp lid. long tube bbk. bbk 3 inch exhaust bbk tb stock bottom end sotck internal motor has never been opened beofre and a nice tune and i put down 438 hp? Im in florida tho sea level ..but yea dyno numbers dont mean anything to me its about how it runs.. but i agree with the "should be putting down a few more ponys theory " thats a bit low for your build i think? taking all the variations of atmosphere and things like that i think u should be making a bit more than that just from my past builds

punisherls6
09-28-2012, 01:20 AM
Just to back my statement up a bit my buddys z28 cam only ls1 auto is putting down 404 with supporting mods of coarse stock ls1 internals .. u have a fully built ls6 and are only laying 26 more ponys than that ? What intake and tb are u using? Somthing is deffintly holding u back. Sounds like a surpreme build tho bet it runs like a beast