Headers

I had headers on my 409 years ago but the only thing I pulled was hole shots.

Two major problems with headers I added to a 454 chevy that I used to tow my 5th wheel.

1. It took numerous trips before I was able to isolate the starter, cables, spark plug wires and speedometer cable from the heat of the headers. I had to put heat shields on everything to keep from burning it up or melting it.

2. The loss of back pressure when going down hill was less so I had to use my brakes more often.

Oh yeah and one more...Even though the truck had a great sound to it, when on a long straight the exhaust note became monotonous and even memerizing to the point where it would put me to sleep. I'd have to turn up the Rock 'n Roll to keep me awake.

Installed headers on a 93 GMC K2500 with 454, They helped a lot with that motor, moved heat from under the hood and down the exhaust. Motor ran cooler, engine could finally breath, I also had a K&N cold air kit and chip installed. The motor was a dog before these changes. The new trucks are pretty well done from the factory so not sure how much gain you would get on one.

I also had a 62, 409 dual quad SS Impala, wish I still did.

I've been involved in the auto racing community for most my life so have some degree of familiarity with headers.. I have also installed headers on tow vehicles with mixed success. The things that seemed to hold true in all cases were:
1) it cost a lot of money to buy, install, debug (heat issues and leaks) headers
2) marginal gain in power
3) no long term gain in fuel economy
4) the heat destroyed the headers inside a few years (and I do not buy el-cheapo headers)
5) I generally ended up asking myself why I went through it.

If you are really hurting for power, I think that you will get some help with the headers, but the cost of entering the game properly will need to be paid..
Most rigs would benefit from dual exhaust with chambered mufflers and dual catalytic convertors (where required) more than they would from headers connected to a stock exhaust system.

My $.02 worth anyways..

Regards - Randy

my experience has been the same as big foot. I am not ever going back there again.

My experience is positive....but then again I used to be a mechanic so I do more than just headers alone and I do all the work. On both my 01 Vette and 99 Tahoe 4x4 I installed quality stainless ceramic coated headers AND other items to compliment, including cold air intake with K&N type filter, higher ratio roller rocker arms, high flow mufflers, PCM tune, etc.

That is the only way to get the max benefit.

Vette went from 350 hp to ~420.....31 mpg at 80mph.
Tahoe not dyno'd but still pulling at 120 mph and gets 20 mpg at 65 mph (oem rated 16). Pulls my 6500 lb trailer and gets 10 mpg.

mine was positive as well. I have the Chevy in the sig line and had to replace the engine so I did the install myself with a factory GM engine using ceramic coated headers. I has a bit more pep and cools down quicker than regular headers.

I would do it again if I had to. Just be sure to buy quality headers.

Thanks for all the advise

the bear II wrote:
Two major problems with headers I added to a 454 chevy that I used to tow my 5th wheel.

1. It took numerous trips before I was able to isolate the starter, cables, spark plug wires and speedometer cable from the heat of the headers. I had to put heat shields on everything to keep from burning it up or melting it.

2. The loss of back pressure when going down hill was less so I had to use my brakes more often.

Oh yeah and one more...Even though the truck had a great sound to it, when on a long straight the exhaust note became monotonous and even memerizing to the point where it would put me to sleep. I'd have to turn up the Rock 'n Roll to keep me awake.

2 is impossible unless you have your foot on the throttle while going down hill. It does not matter if you have your backpressure upstream or downstream of the engine and the throttle plate is a Waaaaaaaaaaaaaaay bigger restriction then any cast iron exhaust manifold.