I've mentioned this header before -- Jeff Winter at Rallye/sport has a very nice 3-into-2 header that has seen many hours on the dyno to get perfect. The primaries are stepped. At about 6 inches from the head, they step up an 1/8" inch and several more times step up until they collect into the two 2-1/2" pipes. This stepping keeps any of the pulses from backing up -- this reduces back pressure.

The header costs $450 but will add some HP over any other header you can find. It looks very similar to the MSA 3-into-2 header. Jeff can tell you a heck of a lot more about it - he can be reached at 303.427.0510.

The trick to get the most power from the header is to run two 2-1/2" pipes from the header back to a 2-1/2" into 3" y-collector at the differential. From there, run a small flowmaster muffler and terminate with no shorter than a 9" pipe from there. This seems to be the best set up -- or so the guys who have done a lot of dyno testing say.

Like 2Many mentioned, I had the problem with my intake manifold flange being thicker than my header flange. I welded some 16 gauge steel tabs to the header flange (1/4" wide by 1/2" long) to raise it to the same level so my header washers would provide consistent torque for both flanges.

Acording to my old Haynes manual the torque specs are:

8mm--12ft-lbs

10mm--35ft-lbs

Ok... got the two headers off--none of the bolts/nuts required much effort to break loose, and they are all the same size (they all take a 12mm socket)--should I guess that they are therefore all 12ft-lbs bolts? I know it's not terribly structural, and I mostly need a good seal. Any recommendations?

Chris

I had a MSA jet hot coated 6-1 header

out 2 1/2" to a dynomax muffler.

Loud and Deeply Smooth. Not loud enough though to affect your stero volume (if you have a modern one) even with the windows down.

Loved it!!!

If you don't like loud then don't go with it.