93 C1500/98 LS1 dyno pull

[RedHeartbeat]

Well, here is an Autotap log on the tune. Could a crankshaft relearn procedure need to be done on the LS1? I have never seen the error code for the relearn on an LS1. I am surprised there is only about 1.1 degree of knock retard.

[motoxlifer]

Hey redheartbeat what kind of #'s do you think you should have if everything was right? I'm just curious cuz my dyno #'s were low imo too 328rwhp with an afr of 14.2:1. Looking at other peoples #'s is somewhat dissapointing, I'm seein cam only #'s of closer to 400rwhp on other sites. How much difference do you think it would make if my afr was closer to 13:1?

[RedHeartbeat]

I keep hearing that we should have wideband readings of 11.8-12.2 under WOT on the dyno. Mine, like yours, was at 14+. Not good for the engine they tell me. The guy running the dyno didn't want to make the pull but I told him I drive it every day like that so give it hell. The LS1 stock is supposed to be right at 400hp at the crank or close to 310 at the rear wheel. Start adding good performance parts and it's supposed to climb. The tune should make it there easily. GM rated the LS1 at 320HP I think but they rated them low to help the customer get better insurance rates. Magazines have been baseline testing these engines and 400Hp is almost always the reading fresh out of the crate on the engine dyno.

I am going try to get down to Allen's so we can fix my tune and maybe we can spread the wealth of knowledge afterwards.

[chrisj6]

wow! 40* under acceleration!? I think about 30* give or take a few, should be your max under acceleration. I dont think I see any more than that. Commanding about 26* at WOT will net you around 29-30* if your AFR adder is still enabled. Is it just running wayy too rich under acceleration and maybe the AFR adder is kicking in way before its supposed to giving you too much advance?

[RedHeartbeat]

My logging software is Autotap and since the PCM constantly cycles the 02s up down so I can't really tell the readings.

[motoxlifer]

Well I'm still a bit confused as to where I should be hp wise. The link below shows a bone stock '98 f-body & vette with peak #'s of 292rwhp & 285rwhp respectively. When GM rates HP are they useing flywheel or rwhp? because according to this article they're underrated at 305 & 345. Going by this article my #'s aren't too bad, but looking at other peoples #'s I'm falling well short. http://ls1tech.com/forums/showpost.p...39&postcount=2

When you get your tune fixed let me know cuz I think we should be in the same ballpark

[RedHeartbeat]

GM HP ratings are at the flywheel. All manufactures that I know of use flywheel HP for ratings. Your's sounds pretty good.

[chrisj6]

Yeah the manufacturers use flywheel hp and tq, my main goal is to beat the stock rated flywheel hp with hp at the wheels before I spray it.....yeah Charlie u heard it right.......i'm sprayin it!

Chris

[Tim Z]

shure would be nice to actually know how much power an engine makes, too many ways to change numbers, crankshaft H.P., flywheel H.P., rear wheel H.P., SAE H.P. gross H.P. , man enough already! it would be nice to have just one way to measure horsepower, now granted i know you need to measure h.p. differently when its just an engine on a dyno verses when an engine is in a vehicle, but manufacture's twist the numbers and no one knows for sure what is what, look at the 427s back in the 69 camaros and chevelles, they were rated at like 450hp and were really 550 +! or the 69 DZ 302 rated at 290 h.p. was really like 400h.p. and that s why it kicked ass on the street. my dads old 87 vette was only 245 h.p. at the motor, but that car hauled ass in its time. i think seat of the pants should sometimes overrule h.p. ratings.

[Zick]

Hey red, what size cam are you running?
Yours sounds like mine did the first too.