L99 guys headers with out a tune

[Super Sport 6.2]

Well I went to talk to my dealership where i bought my 2ss/rs l99 and 4 other cars from and I told them I was going to install headers and a tune and both the service manager and sales man (same guy for 5 cars) told me maybe I can get away with headers but not a tune. So is it worth me doing headers with out a tune i still might do a tune because i know LS engines are top notch i just worry about the tranny a little bit. I heard headers with out a tune messes with timing a little bit so does that hurt the engine and is it worth the gains

Thanks
Rick

Vararam, Magnaflow Mufflers and X pipe, and V-max ported t-body

[Supercharged SS]

Originally Posted by Super Sport 6.2

Well I went to talk to my dealership where i bought my 2ss/rs l99 and 4 other cars from and I told them I was going to install headers and a tune and both the service manager and sales man (same guy for 5 cars) told me maybe I can get away with headers but not a tune. So is it worth me doing headers with out a tune i still might do a tune because i know LS engines are top notch i just worry about the tranny a little bit. I heard headers with out a tune messes with timing a little bit so does that hurt the engine and is it worth the gains

Thanks
Rick

Vararam, Magnaflow Mufflers and X pipe, and V-max ported t-body

The headers will move the cats which is a big no-no. That in itself is enough for GM to bust your balls. IMHO, it's not worth the 20 or so rwhp you get if the warranty is something you value. In all seriousness 20 rwhp isn't a big enough difference to possibly have your warranty voided. In the ends it's your call. You will also get a cel with headers and no tune.

[Super Sport 6.2]

Thanks for the info Supercharged how much hp am i looking at if i do the tune and headers. I am leaning towards both but i am kind of a conservative guy i just dont want any problems from the car

Thanks
Rick

[SilverSS3108]

30rwhp with both... I ran just the LTs for awhile with no tune and when I finally got a tune I found out I was running crazy rich.. I'm not running cats though... Try high flow mids... I don't think you have to have a tune for them and they make good power and they're cheaper... Ask Padre here on the forum...

[brantley847]

I don't think you HAVE to run with a tune, but the thrown CEL code is annoying... also your remote start won't work if the CEL is thrown.

I only ran mine without the tune for about 100 miles... ran a little rich like silver was , and I was worried running it that way may have some consequences to it so I took the jump.

Removing AFM and the surging that comes with it was well worth IMO, but if you value the warranty and potentially having to pay thousands in power train repair, you may want to consider waiting. But I tell you, LTs coupled with the mods you already have would be friggin sweet.

[Fiftydriver]

The actual gains with both the LTs and tune will not be HUGE as mentioned already,

BUT!!!

If you get a good tune, such as a header tune from Jannetty Racing, it will do much more then just give you an extra 30 HP with your headers. What it does as well is turn off certain programs in your ECU such as torque management system and AFM systems. The way I understand the torque management system is that the computer retards the amount of torque the engine can produce up to a certain RPM level. This makes the cars feel much heaiver at the start(At least once you have felt the car with this program turned OFF!!)

This will allow you to put pretty much all the low end torque that the L99 produces to the ground right off idle and it is a NOTICABLE difference. Also the custom tune will also tweak your TCU so your transmission will have sharper shift points and hold your shifts longer in auto or sport mode. My L99 will shift right at 6200 RPM every time on the money if I just mash the throttle land let the tune do the rest. This is also a noticable change over the factory tune.

The AFM system was simply an annoyance for me. I hated hearing the engine drop into this mode and then come back in when the throttle was hit. Just drove me nuts and if you put on some custom exhaust parts you will notice it even more then with the factory pipes.

My L99 averaged around 23 mpg on the highway with the factory tune. With the JRE tune which elimianted the AFM system, I averaged over 22 mpg for all around driving, city and highway so I see no advantage to having this system active.

I would certainly go with a good set of LT headers, good high flow cats and a tune. I would also strongly recommend a good quality cold air intake. The CAI in combination with the LT headers made a huge difference in my L99 as far as how freely the engine reved up.

When I got the tune from Ted I asked him how much added power I could expect, I believe he said something like 50 HP with the CAI, LTs, HF cats, Corsa Exhaust and his custom header tune. I may be wrong on that exact number but it was in that range. That said he also stated that the car will feel more like you added +100 HP because of the torque management system turn off and he was very correct!!!

IF your going with the LTs you might as well get a tune and a CAI as well. Just my opinion. My L99 turned into a totally different car with my short list of add-ons.

Be careful though, its a slippery slope!!! Next will come custom differentials and lower gears and high HP axles and Superchargers and all kinds of other power toys!!! Once the warrantee is gone, your free to play and its hard not to play with more add ons on these cars!!

Have fun.

[mlee]

Sounds like your dealer gave you good advice... now it's up to you whether you tune or not. There are folks who run LT without tune and just deal with the CEL. But with the L99 you will hear the AFM groan much more with headers. Probably best to just wait until you are ready to tune.

BTW there are a couple of mod friendly dealers in your area... feel free to send me a PM.

[BowlingSS]

IMO life is too short not to enjoy our cars the way we want. I just installed LT's and also did the tune. The L99 shifts soo much better now and I can feel and hear the difference. It is really up to you. I am starting to save for a high stall now.

Good luck.

Bill

[GB EB]

Originally Posted by BowlingSS

IMO life is too short not to enjoy our cars the way we want. I just installed LT's and also did the tune. The L99 shifts soo much better now and I can feel and hear the difference. It is really up to you. I am starting to save for a high stall now.

Good luck.

Bill

SW LTs w/HF cats on the way. Appt. set for install and tune.

I'll post results at the end of the month

[brantley847]

fifty may have mentioned it...

but also, I actually improved my MPG after the tuner got a hold of the Camaro. I consistently get 16.5-17.5 mph city now.... I was pulling 14.5-15 before, and I have a heavy foot.

[Super Sport 6.2]

When you get a tune do you have to tell them what you want done/ turned on or off or do they find whats best for your car based on the mods you have.

Thanks
Rick
Vararam, v-max ported t-body, X pipe and Magnaflow mufflers

[mlee]

Originally Posted by brantley847

fifty may have mentioned it...

but also, I actually improved my MPG after the tuner got a hold of the Camaro. I consistently get 16.5-17.5 mph city now.... I was pulling 14.5-15 before, and I have a heavy foot.

Back in the beginning I too gained MPG with a tune but it ended up being a wash by turning off AFM...

Originally Posted by Super Sport 6.2

When you get a tune do you have to tell them what you want done/ turned on or off or do they find whats best for your car based on the mods you have.

Thanks
Rick
Vararam, v-max ported t-body, X pipe and Magnaflow mufflers

Short answer is they will run your car on a dyno and adjust fuel/timing etc for the mod that you have installed. Find someone who does lifetime tunes so as you add things like Cam or Super Charger the tune part will be free. It's also nice to get a before and after dyno run so you can see the difference...

[Super Sport 6.2]

Thanks guys for the info looks like I will be going to G Force in a week or so for Headers, cats and a tune

Thanks
Rick

[mlee]

Originally Posted by Super Sport 6.2

Thanks guys for the info looks like I will be going to G Force in a week or so for Headers, cats and a tune

Thanks
Rick

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