I have an 89' GT convert with a 5 speed and 3.55's. It has full length headers, off road h-pipe and flowmasters. The car also has a ram air hood and stock heads. For the next purchase I'm considering either a new intake or a larger mass air and throttle body. I am not concerned about extra work created by either install. Regardless of the choice I make the other choice will follow in a few months to a year. Which of these two choices will create more power.
Thanks,
Gordon McLeer
A ported lower intake by TMoss will Net (on Avg) about 15-20HP. Only costs around $100!!
A larger TB 65-70 around 3-5HP.
To answer "Mr. Ford's" question first, "full-length" headers are long-tube aftermarket headers. While they build a little more power than stock or aftermarket shortie headers, they are _not_ emission legal because there aren't any catted H-pipes that fit them -- the cats would be moved too far downstream to be effective.
Gordon,
Don't expect either, or even both series of mods done together, to increase your horsepower very much. Neither the intake or TB/mass-air meter is as much of a kink on your intake side as your stock heads are. That being said, I would go with a larger mass-air meter and the aftermarket intake first. Personally, I don't think the stock 60mm TB is as much of a restriction as the other two.
Before you make your purchases, know what the "plan for your car" is. Wildly throwing parts at your engine will not make the horsepower you're hoping for/expecting. If you're going to build a monster dragstrip only car, then the shortest intake, biggest valve heads, big cam, largest TB/ mass-air meter is what you should probably be buying. However if you want a good strong street engine, then keep all your horsepower purchases on the conservative side. Generally speaking, that means slightly larger valves (i.e. 1.84 or 1.90) long runner intake (i.e. Cobra or GT-40), mild cam (i.e. E-303) and slightly larger TB (i.e. 65mm) and mass-air meter (i.e. 73mm or 75 mm). Getting a matching set of performance parts is the key!
Hope this helps. If you have more questions, post away.
Patrick '93 Cobra '83 LTD
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