integrale4wd said:
Mike,
I definately am willing to purchase some headers and even do your TB conversion. The big question now is aftermarket headers do they crack? Also is there a place where I can purchase already a bored out TB?
thanks a lot,
Anthony
Headers from Hotshot & Bosal are largely above reproach from a quality perspective. I've not really heard any bad things about them in terms of leaks or cracks. MSDS headers (which appear to be Hotshots with coating) are also good. A bit lower on the quality (and price) scale is Pacesetter. If armor-coated, their corrosion resistance is much improved over their black-paint models (which get rusty and look bad after a week) but I've heard nothing good about the ball-joint they replace the flex-pipe with and some say the weld-quality is questionable. You can't beat the price though.
HS & Bosal preserve the tuned-length of the stock system which preserves the smooth exhaust note the OEM system has. Pacesetter goes with long, unequal-length (between front and rear banks) primaries which may help torque production but which makes the exhaust note more reminiscent of a GM V6. Some like it one way, some the other.
Many people have trouble with the EGR fitting on the rear bank. In some cases, poorly fitted pipes have caused under-hood fires because the hot EGR pipe burns through the nearby power steering hose, spraying the hot header with hydraulic fluid. This has as much to do with installation as it does design. In other cases, the fittings on the headers don't match the pipe fittings etc. I think HS has this worked out by now and I'm not certain it ever was a problem for Bosal.
I'm not sure if RC Engineering is still doing TBs but you can try them. Any good local engine machine shop should be able to bore your stock one (or one you buy from a wrecking yard) and make up a new throttle plate.