L99 owners with slow cars going to dealers for fix.

[leviticus88]

Originally Posted by pharmd

I ran my BMW 335i (which we traded in on the SS) at the track the week before we traded it in...the weather was comparable to what I ran the SS in, it ran 13.9 @ 102....it is rated at 300hp.

You guys need to check your trap speeds...if other cars are trapping the same or more mph than yours, that is a pretty good indicator they are making as much or more power than you are, and suggests that if you were to get into a highway run, you'd get pulled at higher mph's.

I agree about trap speeds but Just make sure comparing the same "types" of vehicles. Such as rwd v8 (auto or manual) and similar weights. My 230whp fwd traps 101 with a 14.5 quarter. It doesn't have 300hp at all. lol But it weighs 2800 pounds.

Get my drift? Only compare cars that are close to the same weight and have the smae types of motors and drivetrains.

[PQ]

Originally Posted by pharmd

I ran 13.9 @ 102 2.21 60' DA +3000 bone stock, the stock dyno's were
317 rwhp/329rwtq (first pull), 321rwhp/332rwtq (2nd/final pull).

When I used the correction factor for my DA, it suggested I would have run
Altitude (in feet) Elapsed Time Factor MPH Factor
3000 .9640 1.0381

My corrected time...13.39/106.09

When I saw my times I was disappointed, I wanted a 13.6 @ 104-105, but considering the weather I didn't feel they were that far off, so when I calculated the correction times, I knew they were within reason of GM claims.

That's better than mine runs allready. Thanx for the info.

Originally Posted by Unfair

wasnt this why all the quality checks and holds were done? they still can't get it together?

Most of them I think are running fine.

Originally Posted by JHart

what kind of car is she in?? that appears to be one of the newer model lexus' in your sig, and if it is i beat one in my truck(it was a friends car) to about 85 and they got side by side and couldn't pass me. my truck is no speed demon, so something must be up man.

It's the IS350. The faster of the original two.

Originally Posted by PatrickfromMD

My L99 feels like it was tuned by the Cadalic division
During the Q&A session at Carlisle, I praised the GM team for a job well done , and mentioning some of the things I really liked about the car, but then opened up into a question about my poor dyno run for my L99, and if I was seeing expected numbers or something outside the expected parameters. . Al came back and asked me what the numbers were (I did not initially mention the specifics as I did not want to seem bashing to an otherwise fine car in a public session) . I told them it was a conservative dyno (Superflow) but it only made 305 WRHP on its best pull. http://http://www.camaro5.com/forums/showpost.php?p=613731&postcount=14
They did not have a lot of suggestions, and I did not want to back them into a corner, so I just praised the car and moved on. At least they were all there to hear my concern (Scott Settlemire, Cheryl Pilcher, John Fitzpatrick, Al Oppenheiser and John Cox ) as well as hundreds of others. Later (after the public session) I showed AL my dyno sheet. I mentioned that my dyno operator had run a LS3 car a few days before mine and had said the timing curve on the L99 was more conservative than the LS3. Al appeared to concur that the setting were less aggressive on the L99.
Al did say that he attends a teleconference each week with the dealers where issues are brought up that seem to be occurring regularly. He suggested I have my dealer look at it, and that if they have concerns that they bring it up during the call. (He also suggested I run in sport mode more, and although it des not seem to help in Engine performance, transmission shifting is somewhat better)
I plan to take the car to the dealer and mention they look at this avenue.
Scott what was your dealer specifically going to try and do?
I spoke to Al a bit about the limitations of the DOD, but there was a lot going on around us and we did not have the time to get into detail about it. I did get the impression that some of the tuning is there to help with the reliability of the AFM (DOD). I wish I had had a chance to explore that subject in greater detail, as well as Torque Management. Al said there is always the chance of updates to the computer tune, and that the performance parts group would likely offer performance tunes (I hope to hear more about that).
I hope to get mine to the track with 2 other guys (another L99, and an LS3). And hopefully run them all together and have some more data to compare.

The pic is with Al and myself... real smart guy!. (note rolled up dyno print outs in my hand). BTW - He brought his teenage son, boy, thats one lucky kid.

Cool. Let us know if you hear anything new.

Originally Posted by SGOS252382

It sounds like things are slowly getting to the people who can make some decisions.
The news of performance tunes for the L99's also sounds promissing. I've never heard of GM offering anything like that for the LS1's, LS2's or current
LS3's.

Maybe they already know something and they're making plans on correcting it?
(99 Cobra comes to mind).

Let's hope so.

Originally Posted by SGOS252382

It looks like a Lexus IS.
They come with two engines (204hp and 306hp - 09 models). You probably raced the 204hp model in your truck.
The 306hp Lexus IS is a quick car.

But his Camaro SS shouldn't have much trouble beating it.

[DeathChill]

Originally Posted by irpq11

Getting beat by subpar cars. In the same weather and road conditions. There is NO WAY Bonnies car should be beating me like she has. Right now my car is slower than the V6 Camaro. If I wanted the performance of an LT, I would have ordered one and saved about 8k

Curious what kind of car she has (year and model). It says the 2008 IS-F gets a 0-60 in 4.8 and the IS 350 in 4.9. Pretty close to the Camaro, especially when you got the 21" wheels which certainly hinder performance.

EDIT: See it's a 350. Yeah, it's .2/.3 seconds off from the SS' 0-60 but I don't know about the negative effect the 21" wheels have on performance.

[PQ]

Originally Posted by DeathChill

Curious what kind of car she has (year and model). It says the 2008 IS-F gets a 0-60 in 4.8 and the IS 350 in 4.9. Pretty close to the Camaro, especially when you got the 21" wheels which certainly hinder performance.

EDIT: See it's a 350. Yeah, it's .2/.3 seconds off from the SS' 0-60 but I don't know about the negative effect the 21" wheels have on performance.

The 21" wheels won't have ANY affect on performance as far as speed in a straight line. The outside diameter of the whole wheel is the same. Performance may be affected in other ways but straight line speed and power isn't one of them.

And yes the IS350 is really quick but she shouldn't beat me by 9 car lenths.

[DeathChill]

Originally Posted by irpq11

The 21" wheels won't have ANY affect on performance as far as speed in a straight line. The outside diameter of the whole wheel is the same. Performance may be affected in other ways but straight line speed and power isn't one of them.

And yes the IS350 is really quick but she shouldn't beat me by 9 car lenths.

Holy crap, 9 car lengths? That's ridiculously awful. Beat your dealer to death until they fix this (or just for fun).

[PQ]

Originally Posted by DeathChill

Holy crap, 9 car lengths? That's ridiculously awful. Beat your dealer to death until they fix this (or just for fun).

lol Yah, my dealer is really cool actually.

But yup, about 100 feet. Not sure how far we raced but i had a buddy drive hers and we got a simultanious jump. Was over 1/4 mile cause I was doing 120 when I started breaking.

[THE EVIL TW1N]

Originally Posted by irpq11

The 21" wheels won't have ANY affect on performance as far as speed in a straight line. The outside diameter of the whole wheel is the same. Performance may be affected in other ways but straight line speed and power isn't one of them.

And yes the IS350 is really quick but she shouldn't beat me by 9 car lenths.

21" wheels will have a negative impact on performance if the wheels are heavier than stock.

[PQ]

Originally Posted by THE EVIL TW1N

21" wheels will have a negative impact on performance if the wheels are heavier than stock.

Only about 60 lbs. heavier. Not gonna be much of a measurable difference. At least not a full second.

[SGOS252382]

Originally Posted by irpq11

Only about 60 lbs. heavier. Not gonna be much of a measurable difference. At least not a full second.

Each wheel is 15 lbs heavier? If that's true, that's a huge difference in rotating mass. The larger diameter wheels also move that rotating mass further out, even when using tires with the same outside diameter as stock.

So your car will definately be affected by this. And my guess is it would run several tenths slower down a 1/4 mile track.

I've read many different things about rotating mass. I heard anywhere from a
1-2 ratio all the way to a 1-10 ratio. Basically each 1lb of ratating mass added needs to be multplied. So the overall weight added to the vehicle is much more than just the original increase in rotating mass.

I chatted with a guy that went from 38 lbs (stock wheels) to 43 lbs (aftermarket wheels) and he said there was a noticeable difference in his car's performance (didn't give me any specific numbers). But his said he could tell his car was noticably slower. And that's with only 5 lbs per wheel (20 lbs total) of rotating mass.

Your car still shouldn't be running 7.0 sec, 0-60mph, but it will definately be negatively affected 0-60mph and 1/4 mile.

[patriotpa]

Originally Posted by SGOS252382

Each wheel is 15 lbs heavier? If that's true, that's a huge difference in rotating mass. The larger diameter wheels also move that rotating mass further out, even when using tires with the same outside diameter as stock.

So your car will definately be affected by this. And my guess is it would run several tenths slower down a 1/4 mile track.

I've read many different things about rotating mass. I heard anywhere from a
1-2 ratio all the way to a 1-10 ratio. Basically each 1lb of ratating mass added needs to be multplied. So the overall weight added to the vehicle is much more than just the original increase in rotating mass.

I chatted with a guy that went from 38 lbs (stock wheels) to 43 lbs (aftermarket wheels) and he said there was a noticeable difference in his car's performance (didn't give me any specific numbers). But his said he could tell his car was noticably slower. And that's with only 5 lbs per wheel (20 lbs total) of rotating mass.

Your car still shouldn't be running 7.0 sec, 0-60mph, but it will definately be negatively affected 0-60mph and 1/4 mile.

...so what would be the best combination of tire/wheel to get the lowest rotating mass while keeping the OD and width of the tire the same? Titanium is light as hell.

[MuscleCarz]

Originally Posted by SGOS252382

Each wheel is 15 lbs heavier? If that's true, that's a huge difference in rotating mass. The larger diameter wheels also move that rotating mass further out, even when using tires with the same outside diameter as stock.

So your car will definately be affected by this. And my guess is it would run several tenths slower down a 1/4 mile track.

I've read many different things about rotating mass. I heard anywhere from a
1-2 ratio all the way to a 1-10 ratio. Basically each 1lb of ratating mass added needs to be multplied. So the overall weight added to the vehicle is much more than just the original increase in rotating mass.

I chatted with a guy that went from 38 lbs (stock wheels) to 43 lbs (aftermarket wheels) and he said there was a noticeable difference in his car's performance (didn't give me any specific numbers). But his said he could tell his car was noticably slower. And that's with only 5 lbs per wheel (20 lbs total) of rotating mass.

Your car still shouldn't be running 7.0 sec, 0-60mph, but it will definately be negatively affected 0-60mph and 1/4 mile.

I think 1:10 is pretty widely accepted and the faster they spin the more the force. It is exponential. Increase the mass, increase the force. Go faster, increase the force exponentially.

Rotational, unsprung weight is a bish.

[SGOS252382]

Originally Posted by patriotpa

...so what would be the best combination of tire/wheel to get the lowest rotating mass while keeping the OD and width of the tire the same? Titanium is light as hell.

If your worried about performance (drag racing), I'd go with the lightest wheel possible (but it needs to be strong enough), and stay with the original wheel diameter (stay away from + plus sizes). But the real light weight wheels can get expensive. There's lots of good wheels out there.

In a racing forum,I read a comment from a 34 time NHRA Champ that said he ran .5 (1/2 second) slower in the 1/4 mile, when he added wheelsthat weighed 20 lbs more each (80 lbs increase in rotating mass). That just shows how much of an effect a small increase in rotating mass can affect a cars performance.

Why did he put the heavier wheels on his car. They were a present from his son (17'' Konig wheels). So he put them on his car and took it to the track and it ran .5 sec slower than it used to run.

[BackinBlackSS/RS]

Originally Posted by irpq11

Only about 60 lbs. heavier. Not gonna be much of a measurable difference. At least not a full second.

15lbs a wheel and 21 inch wheels is going to have more impact on performance than you think. Probably not the full second, but certainly you will not be getting the advertised times from GM. Having said that, I still believe the problem is in the PCM/TCM tuning.

[PQ]

Originally Posted by SGOS252382

Each wheel is 15 lbs heavier? If that's true, that's a huge difference in rotating mass. The larger diameter wheels also move that rotating mass further out, even when using tires with the same outside diameter as stock.

So your car will definately be affected by this. And my guess is it would run several tenths slower down a 1/4 mile track.

I've read many different things about rotating mass. I heard anywhere from a
1-2 ratio all the way to a 1-10 ratio. Basically each 1lb of ratating mass added needs to be multplied. So the overall weight added to the vehicle is much more than just the original increase in rotating mass.

I chatted with a guy that went from 38 lbs (stock wheels) to 43 lbs (aftermarket wheels) and he said there was a noticeable difference in his car's performance (didn't give me any specific numbers). But his said he could tell his car was noticably slower. And that's with only 5 lbs per wheel (20 lbs total) of rotating mass.

Your car still shouldn't be running 7.0 sec, 0-60mph, but it will definately be negatively affected 0-60mph and 1/4 mile.

Well, I was just guessing on the 60lbs. Maybe more, Maybe less. But rotating mass works in all directions of rotation. What effect it may have one one side will cancel it's self out on the other side.

My freind went up from 16" wheels to 19" wheels on his 300Z and actually said he felt it was faster. The times were identical to before the swap but I gaurantee his wheels were heavier than previous. Maybe a circumfrance difference negating the would be ill effect on his but I don't beleive my wheels will slow the car down.