Anybody using these headers?

[Turbo4whl]

mountie said:
Unless your engine is highly modified, headers is for looks ( sound near engine) only.....

If your engine is near stock, don't waste your time or money. ( Doug Thorley said this )


Can you prove this? Are you talking about Thorley, the funny car drag racing champion? The pioneer in developing the Tri Y headers to increase low end torque?

I find this hard to believe. The "highly modified" part.

Unless someone considerers "highly modified" as a recurved ignition, different carb and cam. I don't. I call that a Chevy tune-up.

 

[Ozzy4194]

Not sure how many guys are still putting headers on these old girls but I did on my low mile 97 and here's my take. Mine had the factory bell type connection to the Y pipe. Stainless. I did a cat back exhaust and couldn't measure any difference in acceleration. Then I put the shorty headers on and dropped a second in my 0-60. It went from 10.5 to 9.5. Any one who says you don't gain anything is full of it. This works out to about 30hp on an acceleration/hp estimator. I also gained 2 mpg which is impressive. I just use the truck for getting around and towing a 17.5 foot holiday trailer and the low rpm torque gains were worth it. The headers were pretty well made but there is one issue with them, the #6 cylinder pipe is too close to the head. I kept burning the plug boots on Cyl 6 & 8. After fighting it for a while I finally cured the problem. Expensive Accel 'shorty' plugs, expensive "Heat Shield" insulation between the pipe and boots and clearancing the pipe near the 6 & 8 cylinder. I wouldn't buy them again for that reason. Looks like JBAs would work better. #6 pipe is routed further away. This is my PSA since my head was spinning trying to find real info on the shorties.

 

[L31MaxExpress]

Not sure how many guys are still putting headers on these old girls but I did on my low mile 97 and here's my take. Mine had the factory bell type connection to the Y pipe. Stainless. I did a cat back exhaust and couldn't measure any difference in acceleration. Then I put the shorty headers on and dropped a second in my 0-60. It went from 10.5 to 9.5. Any one who says you don't gain anything is full of it. This works out to about 30hp on an acceleration/hp estimator. I also gained 2 mpg which is impressive. I just use the truck for getting around and towing a 17.5 foot holiday trailer and the low rpm torque gains were worth it. The headers were pretty well made but there is one issue with them, the #6 cylinder pipe is too close to the head. I kept burning the plug boots on Cyl 6 & 8. After fighting it for a while I finally cured the problem. Expensive Accel 'shorty' plugs, expensive "Heat Shield" insulation between the pipe and boots and clearancing the pipe near the 6 & 8 cylinder. I wouldn't buy them again for that reason. Looks like JBAs would work better. #6 pipe is routed further away. This is my PSA since my head was spinning trying to find real info on the shorties.

I call BS on anyone claiming that headers of any kind are worse than the OE crack prone garbage manifolds as well. I actually put Hooker performance 2.5" manifolds on a mildly modified L31. Then swapped them for Thorley tri-ys. The engine gained over 1 in/hg idle vacuum when the headers went on, meaning even at idle the headers increased scavenging allowing the engine to run more efficiently. At 2,500 rpm with no load the engine gained over 2 in/hg vacuum.

 

[Supercharged111]

I call BS on anyone claiming that headers of any kind are worse than the OE crack prone garbage manifolds as well. I actually put Hooker performance 2.5" manifolds on a mildly modified L31. Then swapped them for Thorley tri-ys. The engine gained over 1 in/hg idle vacuum when the headers went on, meaning even at idle the headers increased scavenging allowing the engine to run more efficiently. At 2,500 rpm with no load the engine gained over 2 in/hg vacuum.

Preach! I can't stand when someone says headers do nothing under 5000 RPM.