FDreaming

Would the powerdifference on a stock port engine be very noticable if using the street port vs. the stockport exhuast that they offer? I have a stock 84GSL but the option to port down the line is open, just not for a while. Would it be worthwhile to just pick up the streetport system now? Or would I hardly gain any power?

dirty86

i have heard that someone went from 100 FWHP too 107 wheel HP with an exauhst

Snapshot

Are talking about the (header-back) dual street port system vs the single stock? If you can afford the dualie- go for it. Since rotarys love to breath, back-pressure is not a plus. It sounds richer, too.

Tom

I can't give you specific numbers but my 85 GSL has 75K original miles on the stock 12A. The rats nests is removed on my Nikki and I use the dual RB system. It is noticeably faster and not that much louder (in fact it is 'music to the ears').

IMO- it is worth it. It will last however long it takes to port your engine..Go for it

FDreaming

Awesome! Streetport setup it is! Thanks for the advice guys.

vipernicus42

iTrader: (4)

If you're planning on leaving it stock port, then there's practically NO difference between their non-SP exhaust and their SP exhaust. However, you'll run into a bit of hp restriction if you buy the single primary system and then port the engine later.

So don't jump straight into SP exhaust if you don't need it. It's also a bit louder. The hp gains on both systems for a stock port car are about 25%.. so 100hp stock becomes 125hp afterwards. It's an awesome improvement where the butt-dyno is concerned.

Oh, if you have a GSL-SE, you need to be careful. The GSL-SE had a 6-port 13b, and had a port-actuator which opened ports when exhaust pressure got to a certain point. Without that extra little tube for the backpressure to go into, the fifth and sixth ports won't open on your GSL-SE and you'll have a problem. E-mail RB, they have solutions for that. If you have an S, a GS or a GSL, you're fine otherwise, either exhaust will work.

Jon

rotary emotions

I have a SP system on my stock ported engine, and it works fine. It's not that loud, BTW.
The main reason to go for a SP setup over a "normal" one is simple: it will leave the path open should you go for a ported engine later. If you are very sure you'll never go streetport (for example because you can't get it through inspections or something) you don't need the SP exhaust system, as it won't be better or something.
But if you *might* port the engine someday, it's always good to keep the options open.

Snapshot

KEEP IN MIND: a stock or SP system- including: header, presilencer(s) & power pulse muffler is going to cost $700.00. Don't skimp on your first go-round & regret it.

RXTbone

Can you hook a stockport RB system onto a streetport? If so, I wonder how much HP you would lose? I just bought a RB header and presilencer, single port for my stock port - and now I'm questioning it... I may build a street port later... GRRRRRRRR.....

RotaryMotorDisorter

I have the RB Streetport exhaust system on my stock port 12a. It sounds nice and the car definatly pulls harder Seems like my car had to work to go up mild hills and after putting the SP exhaust on it, it doesnt have that problem. It sounds pretty good to me, maybe alittle louder than i wanted but its not too loud. Plus if i wanna SP it ill be glad i have it! Do it.

RotaryMotorDisorter

Can you hook a stockport RB system onto a streetport? If so, I wonder how much HP you would lose? I just bought a RB header and presilencer, single port for my stock port - and now I'm questioning it... I may build a street port later... GRRRRRRRR.....


Racing Beats catalog says the SP exhaust system typically adds 5% or more HP over the other system on a SP motor at higher rpm's. So my opinion is that yea, the SP system is nicer on a SP motor but if you dont already have the SP exhaust system, i think ide keep the set up ya have now. It should still be nice.

1984special

Don't dilly dally! RB has increased their prices! Mazdatrix still carries their old price... but it might not be for long!