[raypfaff]

Hello All,

Thanks for reading in advance. I'm a recent proud owner of a '78 Trans AM with a Pontiac 400 6.6L engine and have spent the last few weeks reading up on upgrades I could include with my restoration. The car is stock and in solid shape so my goal is too keep it looking original in appearance. My mechanic recommended looking to increase the breathing of the engine to get more mpg and said while I was at it to add some "muscle" to my muscle car. After looking over some numbers and reading Jim Hand's book I decided my goal was to shoot for an additional 80-100 hp with as much improved mpg as I could find. The car won't ever see the strip so whatever I do will be for enjoying the highway. I put a call into Jake's and they recommended the following. Investing in RAM Air exhaust manifolds, OEM 4 bbl manifold, head work (I want to keep the appearance original and don't want headers ) and mild cam (low to mid 220ish duration at .050). This is what was recommended to me for increasing airflow and increasing hp with my goal output in mind. My question for the community is whether or not those components would be able to get me around the "need" for headers and if anyone has any idea of any mpg difference I could expect or recommend other options. I know the '78 out of the factory was a 12 mpg city 14-15 mpg highway car and have heard of people improving their air flow and going 15 city and 18 highway (hey gas is expensive I'll take the improvements as little as they may appear to some people). Thanks again for reading and I'm looking forward to hearing what you have to say.

Best
- Ray

[1930u]

My suggestions- use headers and before you do anything you should determine your gear ratio. I had a brand new one in 1977 and with the 3:23 gear it got 17 MPG easy on the road but it was a T/A 400 4-speed. Even after I put in a 3:73 gear, headers, cam, and Holley 6210 carb it got 13-14 and actually the miledge improved a bit in town. Good luck.

[RWENUTS]

If you want to keep your factory manifolds and not use headers then check these guys out.
http://www.extrudehone.com/auto/auto-performance.php

[WDCreech]

Your best bet for iron exhaust manifolds are the ones from R.A.R.E. A little on the expensive side, but they're reproductions of the factory ram air manifolds. I don't know if they have a web site, but I'm sure you could find out how to reach them from one of the Pontiac sites, like the Performance Years forums.

Bill