[jimharrell]

Hey has anyone had the Chevrolet licensed ARH headers on their car?

How much louder would the exhaust be even without a tune? Is a tune necessary?

[Bohanan23]

Yes tune is necessary. Yes it's louder.

[Fraxum]

Are they 1 7/8? What is the difference with unlicensed ARH LTs?

(I see off road only and yes 1 7/8. No difference.

[jimharrell]

Originally Posted by Bohanan23

Yes tune is necessary. Yes it's louder.

I assume the dealer doesn't perform a tune on the install, so without a tune would performance be in limp mode with CEL? And it is louder without a tune? Like significantly?

[Bohanan23]

In most cases it wont go into limp mode but AFR will need to be adjusted. CEL will come on for primary cats being deleted. You'll get best results with a tune though. I think Chevy endorsed their own set similar to the CAI made by Cold Air Inductions. I doubt Chevy would still allow a warranty with long tubes though.

[jimharrell]

Originally Posted by Bohanan23

In most cases it wont go into limp mode but AFR will need to be adjusted. CEL will come on for primary cats being deleted. You'll get best results with a tune though. I think Chevy endorsed their own set similar to the CAI made by Cold Air Inductions. I doubt Chevy would still allow a warranty with long tubes though.

Except with the CAI they provide a tune for it and it maintains the warranty. AFR? Yeah I will say since it isn't on the chevrolet accessories site, you can have a dealer do it but it says nothing about the warranty and says it's only meant for track use and not the street.

[lgarrison34]

Originally Posted by jimharrell

Except with the CAI they provide a tune for it and it maintains the warranty. AFR? Yeah I will say since it isn't on the chevrolet accessories site, you can have a dealer do it but it says nothing about the warranty and says it's only meant for track use and not the street.

AFR=Air/Fuel Ratio

[mlee]

Originally Posted by Bohanan23

Yes tune is necessary. Yes it's louder.

No a tune is not necessary... but highly suggested if you want results and no CEL.

Originally Posted by Fraxum

Are they 1 7/8? What is the difference with unlicensed ARH LTs?

(I see off road only and yes 1 7/8. No difference.

There is no difference. ARH is the licensed part for these cars. Buy them where ever you want. MAP keeps pricing it the same where every you go, but I'm betting it's a little higher at the dealer.

Originally Posted by jimharrell

I assume the dealer doesn't perform a tune on the install, so without a tune would performance be in limp mode with CEL? And it is louder without a tune? Like significantly?

No limp mode but you will eventually get a light from the rear O2 sensors.

Originally Posted by jimharrell

Except with the CAI they provide a tune for it and it maintains the warranty. AFR? Yeah I will say since it isn't on the chevrolet accessories site, you can have a dealer do it but it says nothing about the warranty and says it's only meant for track use and not the street.

This mod does not keep your warranty with or without tune.

Also, it will be much louder with or without tune and the bottom line is if you don't want to tune (for whatever reason) I would not add headers.

[jimharrell]

Originally Posted by mlee

No a tune is not necessary... but highly suggested if you want results and no CEL.

There is no difference. ARH is the licensed part for these cars. Buy them where ever you want. MAP keeps pricing it the same where every you go, but I'm betting it's a little higher at the dealer.

No limp mode but you will eventually get a light from the rear O2 sensors.

This mod does not keep your warranty with or without tune.

Also, it will be much louder with or without tune and the bottom line is if you don't want to tune (for whatever reason) I would not add headers.

Thank you for the information. I just want to keep the warranty, that's all. Yeah seems like it isn't worth it without a tune especially breaking the warranty. Dealer was even saying they don't think they could install it.

[mlee]

Originally Posted by jimharrell

Thank you for the information. I just want to keep the warranty, that's all. Yeah seems like it isn't worth it without a tune especially breaking the warranty. Dealer was even saying they don't think they could install it.

Yeah, they don't really do that kind of mod or really any mods. There are a few dealers who are certified performance dealers that might. If you have a good speed shop in your area that's normally best as they do header installs all the time. Somewhere down the line you will ditch the warranty or it will run out and headers are a really good mod so keep it on your list for sure. In the meantime a Catback exhaust might be a good option to get some more noise.

[DorkMissile]

The ARH headers in the GM Perf Catalog are really not meant for daily driven cars (in GM's opinion) so the dealers will not support tuning them.

If your goal is a more aggressive sound - there are a few steps you can take prior to get a better sound without having to worry about a tune

You can put on a axle back as the first level, and a second level would be having a secondary cat delete / gut the secondary cats. This is after the rear set of O2 sensors so there should be no issues with the computer.

If you are considering headers for a performance gain - this is a real expensive way to get almost no power. The advertisements of people getting 15-20hp with headers also includes some kind of tuning, with most of those gains coming from the tune.

The LT1 exhaust manifolds are very similar to "shorty headers", and will actually flow well (I made over 700whp with stock manifolds)

[Fraxum]

Oh, if you are considering LTs consider this besides the cost of the hardware and maybe the installation/tune costs:

• LTs by themselves give about 15 peak RWHP tuned on the LT1. (documented)
• LTs require a tune which means you now completely own the drivetrain.
• LTs require modding the cars catalytic convertors, which is technically illegal.
• LTs will make your car significantly louder, especially at startup.
• LTs most likely will give your car the dreaded drone sound if you do not have NPP.
• LTs will give your car a boomy sound when accelerating and a high pitched scream at high RPM.
• LTs look really cool under the hood.
• LTs are required for all out performance builds
• LTs give you a cool vibe like you just don’t care about the LT negatives or a warranty, you just want to have fun.

.

I am not planning on putting LTs on my LT1 I have ordered. But if I get bored will I weaken?

[JCunningham]

above is correct. The GM ARH headers are meant for the COPO. Thats why they say for track and computation use only. GM will not tune your car for them and they legally can't install them because that would include removing the factory cats. If you find a dealer willing to do it great but you would be better off going to a Performance shop that specializes in GM and can perform a dyno tune. The Performance shop would better know how to do it and usually a cheaper rate. Yes a dyno tune is required as your AFR will be off. Headers will void your drivetrain warranty.