Doug Thorley Headers Installed! Too Many Pictures! LoL
Doug Thorley Headers Installed! Too Many Pictures! LoL Here is another documentary of gratuitous and unnecessary spending, along with more pictures that is probably needed. 
I put the headers on back in early June 2011 and so far they are holding up great as of this post.
Headers and Magnaflow cat back produce a real nice sound. When the engine is first started in the garage and I'm outside the car the exhaust can be felt in the floor. Pretty cool.
DOD mode with fully stock exhaust is barely perceptable. DOD mode with just a magnaflow catback is annoying. With headers and magnaflow catback, DOD mode is INTOLERABLE! It sounds like complete trash.
I use Will overkill for my tune and have HP Tuners. I consulted with Will and he advised me how to partially tune DOD out. So I now have DOD set up to only engage in 4th gear at speeds greater than 60 MPH. This is so much better. I wish I had done this way back when I put the Magnaflow on. Car sounds great in city driving now, and when DOD kicks in on the freeway, the V-4 sound is barely noticable.
So far as performance... Well... Seems to lose a bit on the bottom and pull a bit better up top. I'm gonna have to say that unless you are planning to do an intake and cam along with headers, then headers are pretty much a waste on a stock engine. Some might argue that, but for sure you will never fully exploit the potential of the headers without an intake and cam. Don't get me wrong, the headers kick ***. But if I were not planning future mods, I might be disappointed.
The install is pretty straightforward. The instructions are decent. I did it myself at a snails pace over a 3 day period. No doubt it could be done in an afternoon if done in a fully equipped shop with 2 people.
The major pains are:
The engine oil dipstick tube was a real MF'er to get out for some reason. It was properly stuck in the block.
The transmission dipstick requires some sort of jedi magic to get in place around the downpipe. I could try to explain how I got it in, but it wouldn't be fair to cheat you all out of figuring it out on your own.
The punchline to the above is that I didn't have the flex swapped out initially, so I had to pull the downpipe back out after mocking up the connecting pipe. So I got to do the install the trans tube/down pipe deed twice.
Enjoy the pictures. Hope this helps anyone contemplating doing this.
I put the headers on back in early June 2011 and so far they are holding up great as of this post.
Headers and Magnaflow cat back produce a real nice sound. When the engine is first started in the garage and I'm outside the car the exhaust can be felt in the floor. Pretty cool.
DOD mode with fully stock exhaust is barely perceptable. DOD mode with just a magnaflow catback is annoying. With headers and magnaflow catback, DOD mode is INTOLERABLE! It sounds like complete trash.
I use Will overkill for my tune and have HP Tuners. I consulted with Will and he advised me how to partially tune DOD out. So I now have DOD set up to only engage in 4th gear at speeds greater than 60 MPH. This is so much better. I wish I had done this way back when I put the Magnaflow on. Car sounds great in city driving now, and when DOD kicks in on the freeway, the V-4 sound is barely noticable.
So far as performance... Well... Seems to lose a bit on the bottom and pull a bit better up top. I'm gonna have to say that unless you are planning to do an intake and cam along with headers, then headers are pretty much a waste on a stock engine. Some might argue that, but for sure you will never fully exploit the potential of the headers without an intake and cam. Don't get me wrong, the headers kick ***. But if I were not planning future mods, I might be disappointed.
The install is pretty straightforward. The instructions are decent. I did it myself at a snails pace over a 3 day period. No doubt it could be done in an afternoon if done in a fully equipped shop with 2 people.
The major pains are:
The engine oil dipstick tube was a real MF'er to get out for some reason. It was properly stuck in the block.
The transmission dipstick requires some sort of jedi magic to get in place around the downpipe. I could try to explain how I got it in, but it wouldn't be fair to cheat you all out of figuring it out on your own.
The punchline to the above is that I didn't have the flex swapped out initially, so I had to pull the downpipe back out after mocking up the connecting pipe. So I got to do the install the trans tube/down pipe deed twice.
Enjoy the pictures. Hope this helps anyone contemplating doing this.
Last edited by 08RedSS; Aug 18, 2011 at 12:50 PM. Reason: Changed font
Staging Lane
Joined: Jun 2010
Posts: 80
Likes: 0
ACCEL sure recognized our LS4, but they also seem to think the 2010 Camaro has a 6.3L :/ ?? Is there something I missed, because they already mention the LS3.. Lol, either way, badass car, badass parts, badass work, badass write up.. You sir, are awesome.
Trending Topics
Thanks for the kind words all. Yeah, I'm starting to wonder if someone at Accel was on the pipe the day they designed that sticker for the box of plug wires. I didn't catch the Camaro 6.3 goof. Sure enough, it should be 6.2L.
Registered User
Joined: May 2012
Posts: 18
Likes: 0
From: chicago
no they didn't change anything its a 08 impala ss i got the dip stick out like i said i bent the he!! outta it n had to play with it for about a hour n a half it was really pi$$ing me off but i got that outta the way n now I'm in the middle of getting the back headers off theres just not a lot of room at all any suggestions??
a lot of ppl have said they had to unbolt the motor mount but the guy who i got the doug throley headers from said he never had to do that it was just a very tight fit
a lot of ppl have said they had to unbolt the motor mount but the guy who i got the doug throley headers from said he never had to do that it was just a very tight fit
TECH Fanatic
Joined: May 2008
Posts: 1,769
Likes: 0
From: Fargo, ND
I took off my stb and the rear valve cover and slid the old out and new in that way. Didn't need to remove spark plugs. Just pulled the wires.
I think if you remove the dogbone you could rock it. Sounds like you might have a worn motor mount or something is making it more difficult. The trans tube should be the only pain in the ***.
I think if you remove the dogbone you could rock it. Sounds like you might have a worn motor mount or something is making it more difficult. The trans tube should be the only pain in the ***.
Registered User
Joined: May 2012
Posts: 18
Likes: 0
From: chicago
I'm taking the plugs n sparks out cuz it never been replaced n there 65k on the motor but i just took off the the main electrical harness on the engine on the back of the motor but what do u mean by dog bone u could rock it n when u pulled them out did you pull them out the top or under the motor? what do u mean by worn motor mount