Hark_z

Well just got my car back today with all the mods in the sig and I am scared and worried. The car sounds awesome and performs well but not NEAR what it should. My friend's bolt on LS1 hung with me dead even 30-100. My car should have damn near 400 rwhp, his maybe 320ish. so 7k later my car is a low 13 sec car?? Thought it was supposed to be in the 11's..Is my stock TB holding me back that much?? Tuning was done by a local reputable tuner.

1racerdude

What do the heads flow and what size intake valve?
What CID?
What compression?
What header and size?
What injectors?
What fuel pressure?
What plugs-gapped at what?
Plugwires OK?
What is the valve adj 1/4-1/8 turn or what?

Hark_z

Heads flow 284/225 @.6''/ 2.05/1.6 Ferrea valves
What CID? ???
What compression? I have Felpro 1074 headgaskets .039 (idk)
What header and size? pacesetter 1 3/4
What injectors? Holley 50
What fuel pressure? unsure
What plugs-gapped at what? Tr55, stock gapping
Plugwires OK? Yes
What is the valve adj 1/4-1/8 turn or what? notsure

1racerdude

Sure need that info to try to see if its tune or design of the combo.How much valve spring pressure?
Look back over the post above for comments.

Hark_z

wish I could tell you the valve spring preussre I'm not sure. The guys who did the work on my car just said to do it from a dig M6 cars will hang with you on the highway....Does that sound right? 70+rwhp or whatever shouldnt i win badly still..

1racerdude

Not really. Especially if yours isn't running right and if your car is heavier than his.
Do you know for a fact that it IS making 400RWHP?
Something fishy going on here.
What is his rear gear?
What's yours?
Is yours a 383CID?

Hark_z

Dont know my actualy HP, he has 3.42's, I have 3.73's. Mines a 350ci

1racerdude

Don't believe your 350 is making 400RWHP and that is the problem.
Ya will have to shift in the 6500-6800 range to see what HP ya are making as compared to his.(if it's factory stock--prepair for a rebuild)
A stock shortblock with that cam and heads will have to RPM(big time) to make HP especially with no more DCR than I figure it is running(the computer won't let ya go over 7200 as there are no fuel tables beyond that).If ya had 12-12.5 static compression ya would be about right on the DCR(dynamic compression the engine actually runs on). No it won't ping with that big of a cam.
Ya don't need no 50# injectors either. I am running 42's at 680FWHP. That could be some of the problem if it's not tuned right.

EDIT: I didn't mean change them just get them tuned to the proper A/F ratio. Change them if they can't be brought under control. Shouldn't be a problem.

HardcoreRM125

Ehh, it probably isnt making 400RWHP, but ...

FWIW, Even a complete LE1 package, heads and cam, with most bolt ons, in a M6 car is going to make at/around 380RWHP. Give or take a few.

Even on a LE3 Heads Cam package, I think it only calls for 36 or 42 # injectors. Once you role out the common things ( Such as bad sensors, or too tight valve lash, etc. ) I would think you could look at the tuning. Get it to a sho with a dyno and have them lok at your air fuel ratio.

Does your car feel alot faster?

Maybe your friends car is more modded then he let you know? Sure he doesnt have N20 or something ?

1racerdude

FWIW ya can make 760FWHP with those 50lb's at stock fuel pressure so ya got to get them under control that's all.

SStrokerAce

I would only worry about the installed height and seated pressure of the springs IF you have a large drop off in power over 6000rpm. Other than that I wouldn't worry about that. If the springs were installed where I recomended then everything will work correctly in that department.

If the cam was degreed in correctly AND the rockers are set with very little lash the cam will be fine and is not the issue.

Only thing about cams, is that people automatically think that the cam is the issue when something goes wrong and there are 100 other things that could easily be the problem.

PM me so I can double check some things for you.

Bret

Injuneer

Who did the heads? Are they stock LT1 castings or aftermarket?

Have you taken it to the track to know that it is "a low 13 sec car"?

How "reputable" is the "local" tuner? Was it a dyno tune? If it was, why would you not know the HP? If he didn't dyno tune it, how did he tune it?

"CID" = cubic inch displacement

Sweetred95ta

Did Tim do the tuning? If so, then the tuner is definitely reputable. He does all street tuning. He'll do dyno tuning, but prefers street tuning. Redline did the install, right? If so, then they're reputable also. Did they degree the cam? Where did the heads come from? Stock castings? 225 on the exhaust is a ton for a stock casting head at .600". I'd say get it to the track or on a dyno before you get too worried.

Hark_z

Thanks for the support. Yes Tim tuned it and Redline did the install. They are stock castings.

camzaro28

u say his is a bolt on car, full bolt on, or just some small stuff?
a near full bolton 6spd LS1 will trap 112-114. so if it was a close race i would think u are right where u should be.

edit: just read ur kill story thread. that car might trap 105-107. so, yeah i would say get to a dyno and see what u can find there.