irpq11, L99 Dyno results.

[rpepka]

I guess the point is we want what was advertised within reason and we want GM and our dealers to acknowledge that there is a problem and fix it. We should not be sold slugs! Truth is Randy should not be getting beat by his wife, my son should not be beating me in his 2000 automatic Trans Am and the car should not be running 0 to 60 in 7 seconds. There IS a serious problem with these cars and a lot of others. We should not have to void our warrantee’s to get the performance we were promised.

[SGOS252382]

What's interesting is ADM dyno tuned another L99 that was only making
306 rwhp. So I think the number of L99's that only dyno around 305 rwhp seem to be more wide spead than first thought.

I'm planning on getting my L99 dynoed and tuned in the next few weeks. It will be interesting to see what my car dynos.

And I'm blow away by how much HP and Torque GM has left sitting on the table just waiting to be pulled out with a good tune.

[CamaroSS24]

(800)MY-LEMON. It is the only way to get any kind of resolution when the dealer can't fix a flaw that is hard/impossible to diagnose. Been there. It was the only way to get rid of an SUV I bought brand new that decided to stall out sometimes. Like at stop signs, so the power brakes would go.......Make the call, you have plenty of hard facts and data.

[PQ]

Originally Posted by rodimus prime

Yeah, a tune will help most, but this car had a huge spike in the run and ran way rich. Im just throwing things out there to check. I would think that a leaking injector or 2 would cause a car at low rpms to run rich but even out as rpms increase.

Well, it seems my car had the 'drop' to rich, while the rpms were allready up a bit. The drops accured at 4000 and 4500 rpms.

Originally Posted by Verio

Posts like these add no value to the conversation. He doesn't want to spend 5 grand fixing the solution. He wants the car to run like the other L99's that are getting consistent 13.1's at the track.

Yup

Originally Posted by CamaroSS24

(800)MY-LEMON. It is the only way to get any kind of resolution when the dealer can't fix a flaw that is hard/impossible to diagnose. Been there. It was the only way to get rid of an SUV I bought brand new that decided to stall out sometimes. Like at stop signs, so the power brakes would go.......Make the call, you have plenty of hard facts and data.

Is that a national number or just a local number?

[rpepka]

Originally Posted by SGOS252382

What's interesting is ADM dyno tuned another L99 that was only making
306 rwhp. So I think the number of L99's that only dyno around 305 rwhp seem to be more wide spead than first thought.

I'm planning on getting my L99 dynoed and tuned in the next few weeks. It will be interesting to see what my car dynos.

And I'm blow away by how much HP and Torque GM has left sitting on the table just waiting to be pulled out with a good tune.

Yes, I think the problem is very wide spread. 305 hp at the rear wheels cannot possibly be 400 at the crank.

[radz28]

Aren't stock G8 L76s putting down in that neighborhood - give or take ten horse'? It sounds awfully low, for having 400 FWHP. ALSO, though, if these cars aren't running with the converter locked, that could be the reason for especially low RWHP numbers too. What I mean is, my car dyno'd ~360+ RWHP to the tire with the converter locked. Under the same circumstances, with the only change being running with the converter unlocked, the car only put down ~317 RWHP.

Has anyone confirmed the TC setting?... That may not have to do anything with the AFR, however, that could explain some of the disparity in power numbers.

[rpepka]

Originally Posted by radz282003

Aren't stock G8 L76s putting down in that neighborhood - give or take ten horse'? It sounds awfully low, for having 400 FWHP. ALSO, though, if these cars aren't running with the converter locked, that could be the reason for especially low RWHP numbers too. What I mean is, my car dyno'd ~360+ RWHP to the tire with the converter locked. Under the same circumstances, with the only change being running with the converter unlocked, the car only put down ~317 RWHP.

Has anyone confirmed the TC setting?... That may not have to do anything with the AFR, however, that could explain some of the disparity in power numbers.

It has been very difficult for GM and the dealers to admit that there is even a problem.

[camaro1]

l99 converters are locked at wot in the tune.

Originally Posted by radz282003

Aren't stock G8 L76s putting down in that neighborhood - give or take ten horse'? It sounds awfully low, for having 400 FWHP. ALSO, though, if these cars aren't running with the converter locked, that could be the reason for especially low RWHP numbers too. What I mean is, my car dyno'd ~360+ RWHP to the tire with the converter locked. Under the same circumstances, with the only change being running with the converter unlocked, the car only put down ~317 RWHP.

Has anyone confirmed the TC setting?... That may not have to do anything with the AFR, however, that could explain some of the disparity in power numbers.

[radz28]

Originally Posted by rpepka

It has been very difficult for GM and the dealers to admit that there is even a problem.

You'll get no argument from me

Originally Posted by camaro1

l99 converters are locked at wot in the tune.

I wonder if there would be any benefit to unlocking it at the track. I know my converter never locked at WOT; it was a pretty big stall though (well, compared to the stock converter). Now that you mention it, it seems like that is the norm' for many of the GM cars I've driven lately. My wife's 'Bu with the 3.6 locks at WOT after getting into 3rd, if I remember right, and the rental I have now, with the 2.X liter does the same. Hmm

[camaro1]

auto's dyno #'s really cant be used to tell what you will run in the 1/4 mile,, my 6.0L s-10 with a 3500 10" converter only made 420 hp to the wheels but ran 10.55 in the 1/4

[PQ]

Originally Posted by camaro1

auto's dyno #'s really cant be used to tell what you will run in the 1/4 mile,, my 6.0L s-10 with a 3500 10" converter only made 420 hp to the wheels but ran 10.55 in the 1/4

That's better than a ZR1.

[radz28]

That's a crazy little S10! You must've been making probably 500+ FWHP, no?

[SGOS252382]

I spoke with a local tuner (very well respected LSX tuner) this morning about the L99s low dyno numbers. The L99 he recently dynoed only made 306 rwhp.

He said that the biggest tuning issue (HP related) with the L99's is the extremely restrictive exhaust. He said the exhaust has two cats and two resonators per side. He said it was one of the most restrictive exhausts he's seen. He can tune the L99 to make more HP, but he's limited by the restrictive exhaust.

The L99 he recently tuned made only modest gains in HP (basically brought it to where the L99s should be from the factory - around 330 rwhp range), but he did make pretty significant gains in torque (close to 350 lb ft).

He strongly recommended I get rid of some of the stock exhaust system before getting my car tuned. But he did say his transmission tune would really help straight line speed (which I liked hearing).

So I'm having a hard time figuring out what I'm going to do. I wanted to get my car tuned, but I might want to wait and get some exhaust mods first.

[Ninjak]

Originally Posted by radz282003

That's a crazy little S10! You must've been making probably 500+ FWHP, no?

Hmmm Thats about 475 I think @ the crank. Nice. very nice. Must be some hella of driving skilz as well.