Why isn't my setup making the power expected?
 

OK here is what I got:

Pacesetter LT's w/ O/R Y-Pipe
226/224 110 LSA cam / 7.4" Chromoly Pushrods / 918 Springs
Lingenfelter LS6 Intake
Ported LS6 Pump
Rollmaster Double Roller Timing Chain
TSP Lid
Green Air Filter
Z06 MAF

The person who spec'd my cam said that I should make at least 400+ rwhp on stock heads. I got a dynotune monday, and the max I made was 381.2 RWHP & 364.6 RWTQ. What is wrong? He said when he put the cam in that there was a really unusual amount of preload in the stock lifters, he said he had to shim them. Also, my stock clutch is going out with the new found power that I have. But, several people have said that if the clutch was slipping that I would see it on my dynosheet.

Anywayz, and help recommendations or anything would help.

http://pages.sbcglobal.net/chrismuro...aust/dyno1.jpg

at least 400? I don't think so. Your numbers look good for your mods if you ask me. What is the lift on the cam? Your A/F looks like it could be tweaked ALITTLE but i don't think you'll see much if any gain from that. You want 12.9-13.1 A/F

Also just a suggestion, look into putting a stock MAF sensor in. i'm not a fan of MAF mods even if its a calibrated GM replacement.

Who spec'd the cam?

What lobes? Lift etc

~380 seems pretty good to me for the mods done.

Your making great power for the stock heads.

Chris

seems good to me, theres nothing on the dyno that jumps out indicating powerloss. i see a great tq curve and a cam that pulls hard up to 6500. i say the person who spec'd your cam just overestimated there work.

I have a few questions. What about where the A/F crosses? Is that a sign of the fuel pump not being able to keep up with the demand? And also, what affordable heads would best suite my setup at this point in time?

thanks for the help guys

400+at the motor yes.. not at the wheels...
you dont even have full bolt ons. 381 is good power for the mods you have.
that cam might make 390-400 when you add a pulley and ported tb

get a few more bolt ons and possibly a better tune and see where that puts you. as far as your fuel pump i dont think theres any problem there. for bang for the buck heads cant beat patriot 5.3's or 5.7's.

Your #'s look right in line with the cars I do with Cams close to yours.So I would say your good..

Nick N did my dyno tune. He tried to lean it out a little, but it lost power. What other bolt on's should I get? I know that ASP Pulley is a big one. What difference would the Patriot 5.3L & 5.7L heads make compared to each other? I wanna be close to 500rwhp n/a in the future on a stock block.

unless you go with a bigger cam I don't think you'll be seeing 500RWHP with that. Even with heads I think you'll only be low 400's with that cam.

I highly doubt you will ever come near 500rwhp with just cheap heads. Unless you have a full out drag car, with a huge ass cam and some Stage 3 LS6 heads, you won't even come close. You'll see low 400s with decent heads and the cam you have now.

What year car is it? What plugs do you have and what are they gapped at? Have you checked that intake manifold for vacuum leaks, they are notorious for leaking. Go back to a stock MAF and you should be able to properly adjust that A/F, your to rich even for spray. 13 to1 N/A Between 11+12 to 1 for N20. What is your timing set at?

Did you have a cutout on the car when you dyno'd? With that reverse split, you'll have to use a cutout to get the best numbers out of it. I'm sure you are leaving 10rwhp on the table there, then add some more for the ASP pulley.

well I can change out my cam in the future if I want to go more towards the 500 mark. No, there was no cutout wyhen I dyno'd. The plugs are TR6'sd gapped at a n20 gap , timing was at about 30 degree's I think. So back to my other questions about those heads? What is the pro and cons of bothof those sets?

there has been no vacuum leaks on my intake since the day we installed it, it works perfect...but it does get hot. My buddy that put the cam in my car said that there was an unusual amount of preload in the stock lifters, do you think that could have anything to do with it? he even shimmed then a lil.

Put a pulley and a cutout on the car and dyno again. You won't be dissapointed with the results of those two mods, you'll be damn close to 400rwhp after that. How's the idle with that 110lsa?

great numbers for no heads

This is my latest cam.
I was expecting 410RWHP. This based on power output of a cam with very similar valve events I did but with less overlap.
That setup put down 393/376 through a 12-bolt with 9 degrees less overlap. The difference in the 2 setups is 241 casting heads vs Mike's older version, LS6 intake vs Aluminum Linginfelter, Yellow terra's with 1/2-3/4 turns preload (perfect) vs Mikes' stock ones with 1 1/2-1 3/4 turns preload after shimming. (this *could* be hanging the valves open). Or it could be that the stock rockers are not true 1.7's due to the lack of a roller tip....this would bleed off a little duration & power. The other setup also had an ASP pulley & stock mass-air. Both setups have longtubes & off-road Y with high-flow cat-back.

If your stock clutch is sticking to the floor, it's being overpowered & heating up. I'm not sure if this situation makes a clutch slip on the LS1, but I've had clutches slip on the dyno with no indication on the printout, but once it held gained 20+rwhp. (New clutch & once warmed up it held)

I was also thinking some loss was due to heat-soak of the intake. You can't touch it.....it's gets a lot hotter then I expected.

If the intake is leaking that would explain it....either way I'd like to see what an LS6 intake would do on this motor.

I'd also like to see what it does at the track before any major mods (aside from clutch & figuring out that lean condition up top).

-Shaun