8CYLPOWER

hey im looking into getting a full cat back borla exhuast i also wanted some headers to go with it if any1 has suggestions for good headers to go with the borla i would appreciate it thankss

CrazyAl

Any of the longtube headers are going to make awesome power. It doesn't really matter what brand you pick. I bought the Dynatech kit because it had all the parts that I wanted: headers, X-pipe, high flow cats, O2 sensor wiring, etc. But performance wise any of the major brands should be about the same.

Stay away from the shorty headers. They're not much cheaper than the longtubes (especially when you factor in the install time/costs) but they make very little HP.

sdwndr

Are longtube headers legal?

Also, I have heard that people looking to avoid excessive drone should avoid midpipe upgrades, does the same go for headers? How much would longtubes effect exhaust sound both in and outside of the vehicle?

CrazyAl

Are headers legal? That's a tough question, it depends on what you're asking. Longtube headers are certainly no more or no less legal than short-tubes. The key is that you're changing the exhaust system of your car. It doesn't matter HOW your're changing it, the simple fact is that you are changing it. That's what will get you in trouble according to the letter of the law. The only way to stay 100% legal, according to the letter of the law, is to leave your exhaust system completely 100% stock, or to use only those upgrades which are CARB certified as OEM-replacements, which are few and far between.

Practically speaking though, the only way you'd have legal trouble with your exhaust would be if you had something that was obnoxiously loud and you pissed off the local cops, or if you failed your inspection/smog test. You **** off the cops if you have a very loud exhaust and/or you drive like an ***. You fail the smog test if you take out your cats. So, if you you run mufflers and cats your chance of getting busted is pitifully low, regardless of your headers/H-pipe.

The Dynatech kit that I bought has (high flow) catalytic converters. Cats are expensive, but it means you don't have the smog test hassles. If they do a visual inspection, they will look for cats. Or, if you live in an area where they do a tailpipe test, then you will need cats to pass. The other option is to buy an "off road" X-pipe or H-pipe, and then swap in your OEM pipe (with the cats) whenever you have to get an inspection.

Headers will alter the sound of your exhaust somewhat, but it's subtle. Loud exhaust or resonance has very little to do with the headers. Resonance or obnoxious noise levels come about when you change your cats or your mufflers. H/X pipes or headers won't affect sound levels very much, so long as they'e not also deleting/changing the cats.

It has been documented that the OEM mufflers flow extremely well, and aren't a problem until about 500+ RWHP.

That being said, you change your Headers and Cats if you want HP. You change your mufflers if you want sound. Replacing your mufflers (cat-back or axle-back) doesn't gain you an appreciable amount of HP. You could put in headers with your stock mufflers and your car would sound pretty close to stock...but you'd have some good HP gains to show for it. On the other hand, you could keep your stock manifolds and install just mufflers (or axleback)--in which case you'd be louder, but would have no (or very little) HP gains.

GhostPony

well said!