L99 owners with slow cars going to dealers for fix.

[2010SLVRBULIT]

[QUOTE=O2BQIK;658347]Yes it does, in more than one respect:

1. The larger wheel/tire combo will be heavier, as stated above.
2. The metal wheel is heavier than the rubber tire, so by using a larger wheel with the same overall diameter, you're moving mass further toward the outside, which increases the effect of rotational mass mentioned above.
3. Thicker sidewalls are more flexible and (everything else constant) would provide better traction from a stand-still.


weight would be the significant characteristic between the two(given the same rolling diameter). Aren't they both aluminum alloys(one painted)? And wouldn't thicker sidewalls be stiffer(less roll)?...

[MTron]

Originally Posted by irpq11

Track or dyno like SGOS252382 said. Most L99s are fine.

Ok, just so you know, the total diameter of the wheel and tire on the 21s are the same as the 20s. The 21s have a thinner tire. Make a difference?

[QUOTE=2010SLVRBULIT;661734]

Originally Posted by O2BQIK

Yes it does, in more than one respect:

1. The larger wheel/tire combo will be heavier, as stated above.
2. The metal wheel is heavier than the rubber tire, so by using a larger wheel with the same overall diameter, you're moving mass further toward the outside, which increases the effect of rotational mass mentioned above.
3. Thicker sidewalls are more flexible and (everything else constant) would provide better traction from a stand-still.


weight would be the significant characteristic between the two(given the same rolling diameter). Aren't they both aluminum alloys(one painted)? And wouldn't thicker sidewalls be stiffer(less roll)?...

When we say thicker, we really mean bigger, as in the distance from the rim to the surface if the wheel, not the actual thickness of the material comprising the sidewall

[MTron]

Originally Posted by irpq11

Track or dyno like SGOS252382 said. Most L99s are fine.

Ok, just so you know, the total diameter of the wheel and tire on the 21s are the same as the 20s. The 21s have a thinner tire. Make a difference?

The main issue is not the overall diameter of the tire, as we have established that they are the same. What the issue is, is that on larger wheels, the rim, or the part that the tire seats to, is further away from the hub. And since that is really one of the heaviest parts of the wheel its an issue.

So for the 21's you have the bulk of the mass further away from the rim, which means you need more energy to spin it.

Larger wheels and tires will always rob some acceleration and performance as they move more mass further away from the hub. Even if you had larger wheels and tires that where lighter, if they still had more mass in the outer portion compared to the smaller, they would still rob performance (say all the weight savings were at the hub on the larger ones)

That being said, i don't think that's your problem, it wouldn't make that much of a difference. If i had to estimate, i would say 2-3 tenths of a second to 60. Since most people say they are getting about 5, you should be about 5.2 given similar weather

[addictedtoboost]

A data log using HPtuners VCM Scanner will show what I observed.

The Knock Sensors are Overly agressive to the point that they are pulling up to 10 degrees of timing when they shouldn't, Killing Power.

A custom tune will correct the lack of performance.

I agree GM should make good on this but I would not hold my breath.

Anyone near me with an L99 can stop by for a Free quick pull on the Superflow so we can show some concrete proof to GM.

[motorbuff69]

Ths stock tune on my 2ss auto is 110ft/lb of torque in 1st gear, way to short to brake the tires lose, these cars are way detuned. I was told that they made these tunes week so people would get tired of them and change them so they could void warrantys and save them lots of money down the road.

[pcmforless]

Originally Posted by motorbuff69

Ths stock tune on my 2ss auto is 110ft/lb of torque in 1st gear, way to short to brake the tires lose, these cars are way detuned. I was told that they made these tunes week so people would get tired of them and change them so they could void warrantys and save them lots of money down the road.

They do it because they know most of us are hammer heads with these cars and will run them hard. They still make the advertised HP, but they don't tell you that they limit the low end power so you can't do crazy burnouts, hard launches, etc.... With the fly by wire throttle bodies it is amazing what they can do to handcuff the power that is there. The are assuming less warranty costs when guys aren't able to drive the car as hard with it handcuffed. This is the same reason they do torque management to reduce power during shifts.
Now a days they can't even detect a tune when done right, or even know how to look for them so they aren't doing it for a reason to void a warranty. I've owned many GM cars and of all the things I have taken the cars in for Warranty work for, not a single one has been engine or transmission. I've had bad batteries, radio buttons wearing off, bad intermediate steering shafts, bad hood switches, rear end recall on the Wife's solstice, and other stupid little annoying things, but even with all the mods I've done to my cars I've only ever hurt one GM motor and that was my LT1 in my 94 Impala that I did cam/heads on and after 10K miles and a lot of track runs I spun a bearing.
All my LS based motors in both cars and trucks (Silverado SS and a Suburban) have never had a single problem even after mods like cams, heads, nitrous, etc.... I really bet if you could look at GM's warranty costs over the years powertrain would probably be a smaller percentage than you would think and most of it would be other junk. Bar none, in my opinion GM hands down makes the best powertrains.
If I could have bought my Camaro without a warranty and they would knock $1K off the price I would have taken the offer.

[rpepka]

I took mine to the dealer and they are performing tests on it. When I spoke to them yesterday, they asked me what type of gas that I used. My rep said that they were doing all types of 0 to 60 tests with traction control on, off etc. I said "so I'm NOT on drugs?!” She said “no you’re not on drugs”, I said “so there is something wrong with the car” she said “Yes, there is something wrong with the car”. I could not have been more happy! When I dropped the car off I included a copy of the brochure page of the Camaro that shows the 0 to 60 time advertised at 4.7 seconds and a stop watch. I also printed all the blogs regarding this issue from this blog and others. Take your dyno results as well. Scott says “Once at the dealership, we need your dealer to initiate a Technical Assistance Case through Launch Brand Quality process. So take it back to the dealer and make them keep it until they do something about it. My car has been at the dealer for 9 days now.

[Jekyll-N-Hyde]

Originally Posted by motorbuff69

Ths stock tune on my 2ss auto is 110ft/lb of torque in 1st gear, way to short to brake the tires lose, these cars are way detuned. I was told that they made these tunes week so people would get tired of them and change them so they could void warrantys and save them lots of money down the road.

I can totally undertand if this is happening !!!!!!!!! $hity imo but I beleive it. And False advertisement when they say a car will do something and turns out it really doesnt.

[rpepka]

GM Refuses to Repair my very SLOW L99.

After having my car for 10 days GM says there is nothing wrong with my car. My service writer said the car is very slow, the tech that worked on it says the car is slow, BUT GM says the car is running 0 to 60 in 5.5 seconds and funny the best I could get is 5.87 cheating a little (starting the stop watch after I punched it).

This is really an outrage I have had GM cars all my life which the last one was a 2005 GTO which was much MUCH faster. The car before that was a 2003 ZO6. I don’t know what to do next. I did not have time to pick up the car today. My service writer says I still have an open case number and I can call GM on Monday. She also said that several other dealers are calling in with the same problem but it does not seem like they want to do anything about it.

I am looking for feedback and ideas on what to do next.

[Epitaph]

i bet its in the tune...if you could get your hands on an extra pcm, with a different tune, you could be set. regardless, gm needs to fix this. if you do end up doing that, and you dont want a voided warranty, dont post on here that you did it, government motors will always be watching -.- o.o -.- 0.0

sorry for my sentences. im on an ipod

[Slvr1SSA6]

I dont know if you would want to swap out ecm's. This is from a GM TSB:

quote:
The new Global Architecture electrical systems do not allow controller swaps between vehicles. This includes the 2010 Chevrolet Camaro / Equinox, Buick LaCrosse / Allure (Canada), Cadillac SRX and GMC Terrain. Swapping ECM's or other modules (including BCM, EBCM, SDM, ECC, IPC) on vehicles with the new Global Architecture electrical system will result in damaging both controllers (A NO START CONDITION WILL OCCUR IN BOTH VEHICLES IF THESE MODULES ARE SWAPPED) due to the new vehicle security code protocol (environment) for 2010MY GDS applications.

[Epitaph]

is that talking about swapping the ecm from 1 car to another? im talkinv about a new one from a company that makes them vin specific.

[paul2010]

Originally Posted by rpepka

GM Refuses to Repair my very SLOW L99.

After having my car for 10 days GM says there is nothing wrong with my car. My service writer said the car is very slow, the tech that worked on it says the car is slow, BUT GM says the car is running 0 to 60 in 5.5 seconds and funny the best I could get is 5.87 cheating a little (starting the stop watch after I punched it).

This is really an outrage I have had GM cars all my life which the last one was a 2005 GTO which was much MUCH faster. The car before that was a 2003 ZO6. I don’t know what to do next. I did not have time to pick up the car today. My service writer says I still have an open case number and I can call GM on Monday. She also said that several other dealers are calling in with the same problem but it does not seem like they want to do anything about it.

I am looking for feedback and ideas on what to do next.

My L99 was awsome from the very first day I used only 93 octane fuel. The car really felt strong when I broke it in I drove it like I stole it. My dealership said don't baby it because they have had old grandma driven cars that ran great when driven by grandma but when someone different drove it more agressively it wasn't used to that style and broke. So they said to break it in how I am going to drive it forever and if anything happens we will no right away. Well I never had any problems ran like a top for the first 3000 miles. Then I bought an aftermarket CAI and a catback exhaust and it was unbelievable. My dealership said they would still warranty the car if anything happened no worries. Then at 7000 miles I decided I want more power and a warranty so I scheduled an appointment at Lingenfelter Performance Engineering to get the 650 Supercharged upgrade and it even comes with a warranty. My before dyno was 349 rwhp with exhaust and CAI and I think a lot of stock L99s are dynoing at 330 rwhp +/-.

[Temper]

I have an L99 Auto 2010 2SS Camaro and its weak! I cannot even spin the tires, and if it does NEVER more than 1 second. This is with BOTH traction control and stabilitrak off. The computer is retarded too, the power is NEVER consistent.

400 horse should roast the tires to second gear!