I've got the CorkSport catback on order (supposedly it will arrive next week!), I had to do catback right away since the stock catback is completely disintegrating.

Anyway, on an 88 GTU with the CorkSport exhaust, would the Racing Beat header or the cat replacement pipe be a better idea? I hear the header makes it obnoxiously loud. Racing Beat seems to recommend sticking with the stock exhaust manifold with the fuel injection.

So what is the real power and sound difference between the two? Is it possible to get a header that has a bung for the O2 sensor?

 

well, not sure about the power or performance gains i know rico has the RB header i think he has a down pipe though instead of the cat replacement. the only thing i can tell you is make sure you get the N/A replacement pipe it's got a special adapter for your 6 port activation that you need for the 88 unless you are going to use an rpm switch.

 

POWER vs. NOISE
This is simple, I don't know why this question is asked so much. The stock manifold, cat replacement pipe, and cat back is louder than stock. If provides a modest increase in power but yet it won't get you arrested for noise pollution.

The header, silencer and cat back is loud, raspy, and 'buzzy' at any RPM's above 3500. The power increase is more than the above setup. How much more? Depends on the car...

Average increase with the stock manifold and cat back is about 5-10 HP. With a header, you get 10-15. How much difference you see will depend on the other mods you have done.

Headers really start to make a difference when you port the engine. And yes, you can get a header with an O2 bung.

 

I have the RB header, RB presilencer, and Racing A N1 single muffler (same size as Apex, but a LOT cheaper), as well as a cone air filter on my 91. Yes, it is VERY loud. Yes, I would reccomend it


One thing though....if you get a Racing Beat header, you have to either buy their presilencer, or get a Mazdatrix cat ($450), or get a custom cat or midpipe, as the header does not bolt up to the stock cat location, nor will it reach to the cat back.

 

With either setup I'm planning to ditch the cats and get a presilencer. So basically the only difference I'm looking it is the manifolds.

Who has the header with the O2 bung? Is this an option on the Racing Beat header?

 

The Pace Setter header is the only header that I know of that DOESN'T come with a BuNgHoLe

Get the Racing Beat header

 

My "Pace Setter" header (or so I was told by the sales guy) has a 'bunghole' and fit PERFECTLY from the block to the stock cat . Has lasted over 2 Minnesota winters and lots of hard driving.... rust free.

 

LOL, the bunghole... I hadn't seen it in the Racing Beat pics so I guess I'll have to call and ask... not like I'll be getting it anytime soon, supposedly they've got a two month back order.

 

My car is currently at the shop getting all the piping welded up for my new header. I will report my butt-dyno gains in a little while.

 

Dre, is that header I can get from Summit?

 

Oh my lord. I can't believe how loud this thing is now. It definately got some power, I know that for sure. I couldnt imagine my setup with a cat replacement pipe in there. I would go deaf. ahahahah

 

Mazdatrix sells racing beat headers with O2 bung and a pipe for actuating the 6 ports on 86-88 N/As. If you have 89-91, the ports are actuated by air pump pressure.

I've never heard one with the N1s, but I have the full dual setup from Mazdatrix. Deep tone at idle. In my 48 year old opinion, NOT buzzy or raspy at high RPMs. No "chainsaw" sound. Louder than stock, but as long as you aren't winding it up on residential streets, it's not obnoxious.


Can't give power "numbers", as I don't dyno the car. But, it revs much more quickly and pulls much harder than before. Prior to the exhaust, it labored at 7000 and above. Now revs from 5500 to 8K VERY quickly and pulls hard. I haven't ventured much beyond the shift buzzer.