C6Performance Journal

What they are: Bassani Borla Corsa Hooker Magnaflow Random Tech Loud Mouth LM w/ quad tip center mount SLP Dual/Dual GMMG Mufflex

What they do: increase exhaust flow and alter sound

What to look for: depends on what kind of look and sound your going for. The premier ls1 sounds site here. Spend alot of time listening to the setups and hear as many setups in person as you can. Exhaust is subjective, so get what you like best in terms of sound since its you who are going to be driving the car around.

– Straight through setups like LM and magnaflow (pt# 14267 for just the muffler) are regarded as some of the top flowing catbacks. Flowmaster is one of the worst flowing catbacks for the LS1, it does sound good in its defense. Hooker, Magnaflow, SLP D/D are all great budget cat backs; Corsa, Borla, and GMMG round out the top of the premium spectrum.

– Loudmouth: LM is a love/hate exhaust, it sounds great on stock manifolds with few bolts on’s. When you start adding LT’s and ORY’s it shows its ugly side. LM + ORY + LT = rasp and drone. Try and listen to various LM setups in person to know what your getting into. Time after time people get LM and end up swapping it out since they get tired of its annoyances. To reduce the rasp and drone you have a few options; install some cats, replace the resonator with a real muffler, or install a 12-18″ dynomax bullet. This setup is referred to Dynomouth; Borlamouth is of the same concept but with Borla xr-1 mufflers.

– With the Introduction of the TSP Rumber you no longer have to hack up your LM as the system is basically dynomouth. (Pic 2)

How to install: Follow the instructions that came with the setup. Some tips:

– Use pipe cutters or a sawz-all to remove the old exhaust, cut at the over the axel pipe or muffler.
– A breaker bar comes in very handy, some of those old bolts and clamps are alot harder to get off then you think
– Use alot of penetrating oil (i.e WD40)

B. Headers

What they are: there are 3 styles of headers for the ls1:

1) Shorties: Easy to install, small power gain
2) Mid-length: Not too small, but not so long as to scrape if your car is lowered
3) Long-tube: Biggest and best. Will maximize power as well as exhaust noise

What they do: allow that great engine of an ls1 breath

What to look for:

– Decide which header is right for you. If you want to stay 100% smog legal you’ll need to stay with Shorties only and make sure they have a CARB number.

– If you have an 01-02 car do not bother with shorties. They received a better-designed manifold and flow quite well actually for what they are. You will see minimal gain if any by switching to shorties. If you have a 98-00 car you’ll gain some rwhp from shorties but it wont be much either.

– If you decide on shorties work your other mods around that aspect meaning if you decide for a future cam keep it small (220 duration or smaller).

– ANY headers besides shorties will require a new Y pipe.

– Mac Mid-lengths vs LT’s. The whole Mid vs LT debate will continue to go on, I’ve learned macs can produce great numbers and are a viable option for alot of people. Mac makes headers for 98-99 and 01-02 cars; if you have an 00 car you will need the EGR pipes from a 98-99 car or you’ll need to remove your EGR system.
–Macs and QTP LT’s side by side.

– When buying long tubes what you are paying for is fitment, quality, fit and finish. All LT’s dyno within the same net gain. Swap from one brand to another for the sole purpose of gains and you’ll be disappointed. 1 3/4 sized primaries are more then adequate for stock cubes. If you have a stroker look into some 1 7/8 primaried headers. If you have a high power stock cubed setup you might want to look into a 1 ¾ stepped to 1 7/8.

– Buy your headers with some kind of ceramic coating or get stainless steel. If you cant afford coated headers hold off until you can. If your car see’s alot of winters (real winters; i.e. east coast and mid west, ect) you might want to seriously consider the stainless steel headers, they are more expensive then ceramic coated headers but the chance of rust will be greatly diminished.

– If you plan to lower or are lowered then any long tube other then SLP will tuck pretty nicely.

Long Tubes

Since Long Tubes are by far the most popular headers they receive the most questions; to a certain extent the old adage of “You get what you pay for” rings true. Info on a few of the more popular choices, not all the long tubes available by no means.

Pacesetters: Extremely popular due to there price, coated they can be had for under 400 dollars. Quality is very good for what your spending your money on, welds and collector are good. If you’re on a budget and want LT’s then Pacesetters should be at the top of your list. Mid production cycle Pacesetter improved on some of the fitment issues people were having with the k-member and banging.

Jet Hot/Hookers: The Hooker and Jet Hot Long Tubes are of the same design, jet hot took the hooker design and improved upon it a bit by moving the o2 bungs on the inside of the headers and they use a thicker tubing and have thicker flanges. Both are great long tubes and will run you 500-600 bucks.

QTP/kooks: Both Kooks and QTP are stainless steel headers, and are generally regarded as the cream of the crop. Quality is top notch and they can be polished for that bling look if you’d like. There only draw back is the price, at 700+ they are not for everyone. If you have the money or are the kind of person who wants the best then kooks or qtp is what you want. As far as kooks vs qtp get whichever one is cheaper.

SLP: SLP’s are the long tube that usually sparks some debate. Alot of newbies are drawn into them because of the hp claims slp makes. But as already stated all LT’s dyno within the same range so SLP’s claims are moot. From a quality stand point they are a great header; stainless steel and are ceramic coated. There major drawback is installation and there ground clearance, or lack there of. If you plan to lower your car then pass on the SLP’s or learn to change your driving style or else you’ll endure alot of scrapping. Another drawback is the price as they are 700+. (My personal opinion, if you’re going to spend 700+ on headers then go for the kooks/qtp)

FLP: At first glance alot of people are turned off on the FLP setup because of the price. What you have to understand is the FLP setup comes as a kit with the ceramic-coated headers, Y pipe, cats, and off road pipes. When you look at it from that perspective it’s a great deal and setup. The biggest advance the FLP system has is the ability to swap from cats to off road pipes and vise versa at will. Great for guys who want to run off-road pipes and then need to swap to cats for emissions requirements.

Flowtech: When engeneering the Flowtech headers the premise was to build a Hooker set using half the budget; it shows. The welds, and flanges are very thin and the primaries have a dent in them to “clear” the k-member. Even with the “clearance dent” people are still having issues. Because of the low quality TPS has stopped carrying the Flowtech line of LT”s. If you need a budget header look into the new Pacesetter design or spend the dough on hooker/jet hots.

Others available but not reviewed:
–Thunder Racing Headers
–Dynatech
–Stainless Works
–PPC
–SuperMaxx
–TTS