Headers and Tune??

[Mud]

You can absolutely get your money back on the extended warranty. If it's wrapped up in the loan, you'll keep paying for it through the life of the loan.

However, you can cancel the warranty and they will give you a prorated refund depending on how long you've had that warranty.

Call the warranty company, cancel the warranty and you will get a prorated refund.

You may have to go through the dealer to start the process, you may not have to. Check it out.

[IROCanSS]

There needs to be a sticky or something on the CEL with mods and a tune and stuff.

Listen folks, you can fool the CEL with spacers or "live with the light" but IT'S NOT SAFE.

Why people insist on saying it is is beyond me. CAN you do it, sure but you run the chance of your car leaning out and going BOOM! Either tune the darn thing or leave it STOCK. So many cake and eat it too-ers. If you make a ton of changes to the car GM has no obligation to warranty it, stop expecting them to.

[Bad70supreme]

From the header test thread!


Some interesting tid bits of informations, the A/F ratios were unaffected by the headers or the header size changes, Ranged from 11.7 -12.3 through the pull, the fuel trims also remained constant from size to size.

They have also found that the cars are setup somewhat rich from the factory. This is why so many people are running long tubes without a tune and not having trobble. If you are planning on a cam, why tune twice, if you only want Lts and want to keep your warranty, why tune... no one has posted an engine failer from headers and no tune!

[c-dub]

to my knowledge though has anybody run the LT's without a tune for more than like 100 miles?

[ArmoSS]

Originally Posted by c-dub

to my knowledge though has anybody run the LT's without a tune for more than like 100 miles?

Good point! Wish an expert and experienced person (on this question) would give more insight on this.

Although...Ted did say there's no point in LT headers and no tune

[brantley847]

Originally Posted by ArmoSS

Good point! Wish an expert and experienced person (on this question) would give more insight on this.

Although...Ted did say there's no point in LT headers and no tune

I would like to know this as well, because I have to drive about 90 miles to the tuner I want to use ...

Is there an issue of possibly running too lean for too long? I will be running about 75 of those miles on the highway is the problem...

[Tshepp]

Originally Posted by c-dub

to my knowledge though has anybody run the LT's without a tune for more than like 100 miles?

I did read one thread while searching about a member who had a couple thousand on without tuning and just had the annoying CEL....

[walt353]

Totaled a car with an extended warranty. They refunded the balance.

[IROCanSS]

Originally Posted by ArmoSS

Good point! Wish an expert and experienced person (on this question) would give more insight on this.

Although...Ted did say there's no point in LT headers and no tune

I believe Ted (who is pretty darn experienced) is talking about if youre adding LTs for performance gains. You have to tune the car to get the full benefit.

...otherwise... and it continues. Like I said... CAN you run the LTs without a tune... yes, you also CAN run your car with out any oil but I sure wouldnt do it.

Yes, the cars are set up with a RANGE for the a/f ratio. Maybe some cars lean out, maybe some dont... every car, every engine is different. When you start blasting that much air through with CAI, LTs, exhaust... the PCM will not supply enough fuel... the O2 sensor reads that its lean and throws the CEL... GET IT!? The car is running lean... Probably not very lean but lean...

[caverman]

Originally Posted by brantley847

Is there an issue of possibly running too lean for too long? I will be running about 75 of those miles on the highway is the problem...

Is it possible....sure....and if it gets too lean you could burn a piston. From what I've researched though GM made them fairly rich from the factory so you'll probably be okay to drive that distance.

Another option you have is to buy an SCT tuner from Jannetty. He'll give you a tune that will get you real close right off the bat. Then you'll just log some driving, email him the log file, he'll tweak the tune and email it back, then you upload the customized tune to your car. It still might be better to have it dyno tuned but Ted is going to get you really, really close to a dyno tune. Plus side though is that you'll then have a hand held tuner in case you ever need something again (ex: if you add a thermostat you'll need the fans tuned to come on sooner). This will keep you from driving 90 miles again for a 5 min re-tune since Ted could just email you the adjusted tune.

If I didn't live close to a tuner that is what I would do.

[caverman]

Originally Posted by brantley847

I don't know for sure...I am not a guru on headers, but I was under the impression the sensors were thrown because of a substantial increase in air flow created by LTs....

Basically, making a header that doesn't throw the sensor completely defeats the purpose of headers....?? Again, I could be wrong..

I'm not a mechanical or header guru either but from my understanding this is what's happening with the CEL.

First understand that a CAT is there to get ride of extra emissions coming from your car in order to make the exhaust cleaner. It does this by heating up the exhaust inside the CAT to an extremely high temp in order to burn up the extra contaminates.

There are two sensors for the CAT....one in front that takes an initial reading of the contaminates going into the CAT and then one just behind it to take the finalized reading. If the rear sensor determines that there is no difference, within a range I'm sure, in the amount of contaminates coming out as what went in then it's going to throw a CEL assuming that the CAT is not funtioning properly.

Now what I don't know is exactly what's throwing the code. Is it because most HF cats only have the rear sensor so the computer is not seeing any change in contaminates? Is it because the HF cats are more free flowing and in order to do that they have to have bigger wholes inside the cat, thus not being able to get as hot and burn up more of the contaminates? Is it because the CAT is further away from the engine than the OEM CATs so it doesn't heat up as much?

Again....no guru here....this is just my understanding of what's going on.

[brantley847]

Originally Posted by caverman

Is it possible....sure....and if it gets too lean you could burn a piston. From what I've researched though GM made them fairly rich from the factory so you'll probably be okay to drive that distance.

Another option you have is to buy an SCT tuner from Jannetty. He'll give you a tune that will get you real close right off the bat. Then you'll just log some driving, email him the log file, he'll tweak the tune and email it back, then you upload the customized tune to your car. It still might be better to have it dyno tuned but Ted is going to get you really, really close to a dyno tune. Plus side though is that you'll then have a hand held tuner in case you ever need something again (ex: if you add a thermostat you'll need the fans tuned to come on sooner). This will keep you from driving 90 miles again for a 5 min re-tune since Ted could just email you the adjusted tune.

If I didn't live close to a tuner that is what I would do.

You were supposed to make me feel better about driving to Tampa....sir, you failed.

lol...I know, I have alot of respect Jannetty, there is a tuner very much like him in Tampa and that is where I was headed and that way I at least get a tuner to get a feel for the car hands on...hmm alright then

[Bee]

I've had LT headers with HF cats on my car for over a year now without a tune. I did do the spacer thing with the rear O2 sensor and have around 5000 miles on it...still no CEL.

Now, do I know that a tune could maximize the gains...you bet. But am I happy with the gains I made without a tune so far...heck yeah!

But I'm also pretty sure that the way most tuners will get around the CEL with LT's is by shutting off the rear O2 sensor. This tells me that the car is not relying solely (if at all) on the difference between the O2 sensors to adjust the A/F ratio.

Anyway, just wanted to share my two cents

[Bad70supreme]

You will be fine chillout man! A tune is not NEEDED, I have been told this by a few vendors... everyone knows your getting your full bang for the buck, and your car will run better with... but you are not going to blow your engine driving to the tune shop 90miles