sorry if this been disscuss already but i looking for the racing beat headers for an 89 gtu n/a. ive been hearing about the 5th, 6th port operning or ect. and i wonder what is that. is it really really imporant to deal with if i just bolt on the racing beat header. and on the www.racingbeat.com website, theres a header on the site but i dont think thats the right one for my car is it?

 

89-91 do not use exhaust back pressure to open the ports. So u should be fine w/ any header

 

First of all you should search.

On an 89, the airpump operates the 5th and 6th ports, so installing a header will not affect that at all. They are auxiliary ports that open up at 3800rpm when the engine's under load. It's sort of like VTEC (please no flaming, it's the same concept) in that it alters the timing and opens the engine up for better breathing at high rpm's.

If Racing Beat says it'll fit then it should. They're a very good company.

 

so my stock cat conv. should fit on this http://racingbeat.com/FRmazda2.htm. because i thought it was a single pipe instead of this two pipe on the header. just making sure i dont buy the wrong one

 

if you get the collected headers then get the bonez high flo/ header combo from rx7.com

if you get the true duals then you should get the presilencer from RB. if you want a presilencer for the collected they have one on RB also.

 

The stock cats will not fit with an RB header. You can add a small spacer and run the main cat IIRC. The true duals must go together with all the other true duals parts, it won't bolt to the stock syetem. If you want to bolt it to your existing cat-back, then you'll need: http://racingbeat.com/resultset.asp?PartNumber=16130 you'll also need: http://racingbeat.com/resultset.asp?PartNumber=16408

 

so the presilencer replace the cat. conv. and just bolt on to the rb headers?

 

I dunno exactly what you mean by that question, but the RB header comined with the RB presilencer will mate up to the stock catback.

 

0o0o okay