well guys should i get these?
Doug Thorley Thy 340 C Silver Ceramic Coated Exhaust Headers | eBay
cheapest ive seen em yet. this is a big investment so please give me your opinions. thanks!!
cheapest ive seen em yet. this is a big investment so please give me your opinions. thanks!!

just getting excited for summer! always thinking.
So am I, but we must start to think more responsibly...Then when we actually buy something we know we shouldn't, we can say "I gave it some thought". 
It's ultimately your decision. Only you know your financial situation and future goals for your car...If you can spare $730 and it's going to make you happy, then go for it.

It's ultimately your decision. Only you know your financial situation and future goals for your car...If you can spare $730 and it's going to make you happy, then go for it.
Last edited by SSilver; Mar 18, 2013 at 04:31 PM.
the thorleys werent made over night either, and the reviews were kind of mixed about them. i dont think that theyd be worth it unless the car was going to get a cam and an intake because of the diameter of the tubing? i also thought the thorleys had an issue with the crossover pipe? when you want to switch to a ls1 or 6 intake you had to have a new crossover fabbed or something along those lines. also i recall something about the original downpipe leaking and making noise. you also had to remove the cat and have it welded to there downpipe or go catless? this may be out of date info. i was on the original list to get the headers a few years back and backed out so i never followed it much after the first dyno and track runs with them(not impressive). like i said i wouldnt buy them at that price. id wait on the new headers or wait for someone to post in the classifieds during a demod sale. for that price you could do an ls1/6 intake, and a tune and notice a huge difference in performance (like low to flat 13s with a decent tire)as opposed to the headers which would probably not be noticeable in the useable rpm range. im sure they probably help once your high in the rpms, but if the car has the factory cam, intake and tune seems kind of pointless. the factory shift points upshift early to begin with and the factory cam kind of falls on its face up there anyway so whats really the point of making a few extra hp up there.
the thorleys werent made over night either, and the reviews were kind of mixed about them. i dont think that theyd be worth it unless the car was going to get a cam and an intake because of the diameter of the tubing? i also thought the thorleys had an issue with the crossover pipe? when you want to switch to a ls1 or 6 intake you had to have a new crossover fabbed or something along those lines. also i recall something about the original downpipe leaking and making noise. you also had to remove the cat and have it welded to there downpipe or go catless? this may be out of date info. i was on the original list to get the headers a few years back and backed out so i never followed it much after the first dyno and track runs with them(not impressive). like i said i wouldnt buy them at that price. id wait on the new headers or wait for someone to post in the classifieds during a demod sale. for that price you could do an ls1/6 intake, and a tune and notice a huge difference in performance (like low to flat 13s with a decent tire)as opposed to the headers which would probably not be noticeable in the useable rpm range. im sure they probably help once your high in the rpms, but if the car has the factory cam, intake and tune seems kind of pointless. the factory shift points upshift early to begin with and the factory cam kind of falls on its face up there anyway so whats really the point of making a few extra hp up there.
go with a hogan catless downpipe instead. also do you have dod/afm tuned out because if you dont that might be something to look into besides the sound it makes when it kicks in with any exhaust oil consumption could become an issue. i think cutouts are expensive for what they are. taking the mufflers off and straight piping it is practically free, and i would say the best exhaust setup on an ls4 dollar for dollar. also they sound good with straight pipes and the res switched to (i believe the name is) classic chambered muffler/resonator.
The amount of gains you get on our cars from just a set of headers really isn't worth the cost IMO. Now if you have more engine mods, etc. I could see it maybe being worth it. I've also had the thought of going with a set of headers but I can't even fathom spending over $600 for a set of headers.
The few manufacturers fabricating headers for the 5.3L LS4 have high prices because demand is relatively low. Compare to headers for a GM 5.7L that average around $200-$300, although there you're talking about one of the most popular engines.
The few manufacturers fabricating headers for the 5.3L LS4 have high prices because demand is relatively low. Compare to headers for a GM 5.7L that average around $200-$300, although there you're talking about one of the most popular engines.
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