Doug Thorley Shorty Headers :: +20rwhp, +35rwtq!

[HeavyD]

I'd be happy with 7-12 hp. Shorties are good for being warranty friendly, cheaper, easier to install. You do get some performance increase, and you do get some improved sound. I don't need long tubes, heads, cam, blower, nitrous or 750 hp!

[coptzr]

I installed these on my 2010 M6.Also installed the GMPP axle back mufflers.IMO the seat of the pants feel increased a little.Also believed the mileage went up a tinch.

[lee]

Originally Posted by coptzr

I installed these on my 2010 M6.Also installed the GMPP axle back mufflers.IMO the seat of the pants feel increased a little.Also believed the mileage went up a tinch.

any louder?

[ssmike]

I installed these headers and can say that I felt the difference in torque but not much in sound level. They are a good alternative to high priced LT's and won't throw O2 codes. I think they look great also!

[coptzr]

I thought it was "thoatier" but not louder.Nice when you stand on it but nice at cruising speed.I think it was money well spent.

[fldrummer]

Originally Posted by ssmike

I installed these headers and can say that I felt the difference in torque but not much in sound level. They are a good alternative to high priced LT's and won't throw O2 codes. I think they look great also!

I noticed the same thing w/ my set. I'm sure LTs are still better, but I still laugh at the naysayers that think they do nothing but look cool.

[NinoSS]

Originally Posted by Sean@Phastek

I agree, the dip on the stock pull shouldn't be there, a different stock pull should have been used on the graph by DT. (note the increase in torque at 3500 is the stock tune's torque management settings) The stock car should be making more like 365 peak horsepower to the wheels, not the 359 shown. But shorty headers are going to give you more gains down low on the torque side compared to the horsepower gains anyways.

One more observation is that if you slide the stock graph to the left a little (start the pull at the same RPM), the gains might be even smaller? Given your assumptions that a stock car should make about 365, these shorties should make a little up top. I question the power under the curve though...

Thoughts...

[Strokedhog]

What type of gaskets and fasteners did you guys use? Have you had any sealing issues at the head and downpipe? My biggest problem with headers isnt warrantee issues it's exhaust leaks.

[coptzr]

My car only had 500 miles when I switched.I reused the stock gaskets and they seal perfect.That's even what the instructions want.I agree LT's are better, but I wanted to retain the stock cat's (for now).Not trying to build a race car, got the Elcamino for that, just want a good performer and nice sound.

[DMAX]

Originally Posted by lee

any louder?

I think it is a bit louder , it definitely changes the tone , here are some sound clip before and after headers were installed with a 3'' custom tubes inc. catback .

with headers



with out headers

[Strokedhog]

Originally Posted by DMAX

I think it is a bit louder , it definitely changes the tone , here are some sound clip before and after headers were installed with a 3'' custom tubes inc. catback .

with headers



with out headers

Great sound worth the effort!

[Strokedhog]

Originally Posted by coptzr

My car only had 500 miles when I switched.I reused the stock gaskets and they seal perfect.That's even what the instructions want.I agree LT's are better, but I wanted to retain the stock cat's (for now).Not trying to build a race car, got the Elcamino for that, just want a good performer and nice sound.

Lookin for the same as you not a track car just want better performance.

[HeavyD]

I am concerned about some of the tight bends at the collector section. I have marked them in the picture. I this a big deal, or is it just the angle the picture was taken, or some kind of optical illusion? Seems like a really aggressive bend and would be really restrictive! Any thoughts?

[SSOOCH]

Does anybody know a ballpark figure of how much a reputable exhaust shop would charge to install these? (I realize it will vary from state to state, city to city).