Hey guys,
I would like imput from you guys who have actually put a header on a 89 + RX-7 na...
I have found a sweet 90 GXL 5 spd I want....But I have been really longing for another Turbo...Will this na just leave me wanting more?

I read things about est. HP increases with a header, are they legit?

They don't have emission testing here...Is a going "catless" a good idea as well?

Ideally I would go with a intake, header & free flowing exhaust, what might I expect HP wise from the stock 160 HP?

Any imput from real life experences is great thanks much!

I think the 89+ model 6 ports were activated by the airpump & don't require back pressure for them to open? Is that the case?

Thanks much guys!

 

First of all, it is correct that 89+ models used the air pump to activate the aux ports, so you dont need to worry about back pressure, etc.
If you look on Racing Beat's website, they say that unless you do major intake mods, such as go to carbs, the header isn't going to offer any more hp than their DP/presilencer combo. I'm not sure how valid that is, but I find it hard to believe that eliminating the stock header doesnt free up horsepower. I personally just have the DP/presilencer since I'm dirt poor and couldn't afford the header, and it makes very good power. I didn't actually witness the before/after since the exhaust system was already replaced when I got the car, but the gains are substantial. I'm not sure how much money you are willing to spend on this, but If you have the money the RB full duals looks very good. I think it goes for a little over $1000. I havent heard from anyone else about this system, but it looks very nice. Either way, I reccommend replacing the entire exhaust system except maybe the header, and I highly reccommend the RB exhaust components. They are very well made.
And now for the last question: Will it leave you wanting more? If you're anything like me, and I know I am, you will keep wanting more power. NA 7's can be fast little cars with great handling, but I do wish it had more power. I guess you could always go with a small shot of nitrous

 

Sorry mine is not 89 but 88. I have RB header/pre-silencer/catback on mine and believe they are really worth for NAs. It really pulls stronger than stock but I can't tell how much HP gain I got. If you are/will be looking for more power, I'd recommend to look for TII or FD.

 

N/A's can be pretty quick. Just keep the rpm's up high. I put a straight pipe on '89 GXL and it made a big difference. Especially low end power. Exhaust is always worth it on rotaries.

 

you may be satisfied for a while but then you always want more id look for a t2 and if you cant find one then you should get a n/a

 

you might find headers a bit loud and annoying depending on what setup you use so keep in mind you might need to get a baffle to weld into the headers to quite things down along with a presilencer and catback.

 

In my sig, I have links to pics of my DIY header.
It was way loud before I added the silencers.
Even with the stock intake, it pulled better above 7K than before.

 

I can attest to RB's horse power statement... I had an 89 GTU.. It ran an average of a tenth of a second quicker (on Average) with the STOCK manifold and the downpipe/presilencer combo. At the strip, a tenth of a second can be a a big deal!!!

NOW THEN.. this does NOT mean that the DP/PS combo makes more HP than the Full Header... My top Speeds were about 1MPH faster with the header (on average).

What does this tell me.. It tells me that the stock manifold produces a bit more backpressure than the full headers and that moves the torque curve towards the low end side (not much, but its there), this gives you a bit more low end torque off the light, thus, your 60ft times will be a bit quicker, giving you an advantage over the rest of the track. THe header, onther other hand, has a bit less low end and thus the 60ft times may suffer. However, on the top end, it will have a BIT more HP and thus once you are into second gear and the rpms do not drop below 4500, you have that slight bit of HP to play with.

BUT... that damn header was so freakin loud, i'd never put one on again unless i was planning on adding a supercharger where the added exhaust pressure would definately show up in HP loss through the stock manifold.

 

That is almost exactly what I have found as well on collected systems.

IMO the only time you would want to use a header is with true duals all the way back, and no cats.

 

so the best way to upgrade your exhaust is to just leave the stock manifold but replace everything right after the manifold back

 

Best bang for the buck - full duals.
Check out the links in my sig.

 

Thanks guys,
I have owned a few Turbo II's and I have sold my last 88 GTU. The main reason I am condisering this one is because its SO freakin CLEAN and the guy has some sweet 17" rims on it with Z rated rubber and he has it lowered 1" and has The KYB GT2's (I think they are)

So I already know it will handle outstanding...The only other mod is he has some nice chrome free flowing mufflers on it. (I forgot what kind?) But the clincher might be that it is Black with perfect like new Black leather interior...Very sweet llooking car! Just 54k orig. miles!

I figure in my advanced age...Maybe I don't need to have a super fast car anymore, but it would still be nice not to have to worry about a heavy pig of a SUV not beating you at a light!

I don't want to put a bunch more money into it, maybe a intake & str8 pipe to remove the main cat would make it breath better & run better? I think if I could get a decent 20 HP gain I would probally be cool with it just looking great & handling much better then stock!

Anyone done that set up?
Thanks again for imput!