what size are the primaries
are they port matched to the heads
and how do they compare to asm performance wise
I dont want to spend more money for less performance

and are they long enough to run them open

 

I'm not sure on the primary size but I do know they are different size tubes to compensate for the different lengths of the tubes. The build quality is second to none IMO. THe head flange is THICK! There are no welds in the tubes like the ASM's. They are about 3 inches shorter than the ASM's, which IMO isn't that much.

About running them open ...... you can run them open, but I wouldn't do it because of what goes on with the o2 sensors. What happens is fresh air comes back in the opening as the exhaust gases pulse and passes over the o2 sensor. This will cause you to run incredibly rich. If you are set on running them open, have some pipes made that come back at least 12" from the collectors. That should go with any header.

Any header you get ... get it coated. An uncoated header will not keep the exhaust hot enough to heat the o2 sensor. That too will cause faulty readings and cause you to run a little rich, although not NEAR as rich as straight open headers.

 

different size primaries ...I like it
I think Im sold
thanx for the info