i am considering placing a deposit on the recent run of 455 MT headers that the GSCA is doing. i have a set of poston headers that i bought in 1995 on the car now. the car has a 455 with around 10.5:1 comp, 235/245 cam, Q-jet, 2 1/2 " exhaust, stinger ignition and ported stage 1 heads. what kind of an improvement are these headers over the old poston ones. they say that they have a ceramic coating, is this coating to reduce the heat given off by the headers? i have mine wrapped in that thermotec heat wrap to reduce under hood temperatures. also what is the fit of these headers under the the hood. with the poston headers, they slid right in with ease (from below of course). any help would be appreciated. thanks john
I have a set of original M/T headers on my '68 Skylark GS, the biggest problem was the trans cross member required some modifying so as the collectors wouldnt hit it. Also the steering shaft is very close to one of the tubes and could be a problem with old motor mounts. The hp difference between the Poston and the M/T shouldnt be much and if the tube dia is the same then the torque curve should remain close. I cant comment on the coating as i am not sure who is coating them. The M/T have a very unique sound to them.
You will like the MT's, though there is not much of a performance difference. On a 70 GS, they will slide in from below, but you have to get the car up off the ground because the collectors are so long, and the steering shaft will be close but will clear. The coating is nice, comparable to Jet Hot and others. I have seen VERY little on track performance difference between any of the 17/8" headers, and I have run them all, except the Headers by Ed. For my combo which is comparable to yours except 11.0 compression and Holley 830, the MT's were marginally better than the Hookers, Postons, Kenne-Bells, and Hooker Super Comps. And they have the unique tingy sound that was so familiar to Buicks for so many years. Now, the TA 2" headers picked up my car from 11.43 to 11.36 with no other changes, so if your looking for a gain then a move from 17/8" to 2". Fit was good on the TA's also. By the way my best with the MT's was 11.43 and the best from any of the other 17/8" headers I ever tried was with the standard Hookers at 11.47.
Jim - I saw in another post that you installed a set of these headers on an '86 Chevy 1/2 ton pickup. Did it require any cutting/tweaking of the frame, or bending/dimpling any of the header primaries? I would like to get in on the GSCA deal if I can find out for sure if they will fit my '85 3/4 ton with a 462. I believe the 1/2 and 3/4 ton frames are the same. Thanks
Hi Jim, you answered a question I have been wondering about for some time. I have the 2" KB "pulse" headers on mine and always wondered if 1 7/8" would have been a better header. From what you have found out it looks like the 2" were the way to go. Sorry to get off topic some. Tom
headers I have a set of the club M/T's , the later ones definitely fit better than the circa 1986 ones i had. Those were on my driver until the year 2000. On my '68 i used the Poston 1 7/8 then switched to the 2'' headers from Earick Racing. Those 2'' fit better than my 1 7/8 , performance - wise i gained just about a tenth without optimizing the jetting. Randy
I have a set of club MT headers on my 70. I pulled them off this week because of a gasket leak and found that evey tube was cracked 1/8" - 3/4" at the tack weld on the outside of the flange. This tack was put there to hold tubes in place while they welded them from the motor side of the flange. Caused a major stress riser in the tube though. Love the sound and performance, but the quality of manufacture in my opinion is poor. I have a set of of original (circa 1969) MT and they have no cracks at all. Just got thin over the years of use.
I dont remember having to make any mods to the headers, but they were a used set from a 70 GS. They fit the truck fine.
