what would be the best port for 200 rwhp on an 87 NA. and is there a way to be driven on the street? what is the most you have gotten on a ported 6 port engine? how long would a BP 4port last running 100:1 premix?
Please only post if you have first hand expereance.

 

I've seen a stock 13b 6 port(2nd gen '87) running a haltech computer ( no AFM ), short primary headers and 2 1/4" exhaust make 156 rwhp in an '85 gen 1. I've also owned a '80 gen 1 with a ported 13b 6 port (1st gen) running a 13b 4 port manifold & carb (rx-4 i think?) adaptor plate to mount the manifold, long primary headers and 2.5" exhaust. It made approx 120rwhp (using a G-tech). Considering a standard 13b 6port (1st gen) in a '85 1st gen using a 4 barrel carb and manifold and an adaptor plate make approx 85 rwhp, the ported 13b 6port in my 1st gen makes approx 41% more power. So in theory a ported 6port (2nd gen) should make approx 220rwhp. I ported my 1st gen engine. I opened the auxillary ports as large as they could go. I also cut bridge ports in the auxillary ports ONLY! The other ports I cleaned up slightly. The exhaust ports were opened up considerably (slightly earlier opened, much later closing). The car would idle at ~1200rpm with a slight brap but on occasions it would idle smooth (I didn't have the chance to get it properly tuned on a dyno).

 

6 ports will work great if itsw ported.Bp are driveable,it all depends how much bumper-to-bumper traffic you drive in.If you dont then its ok.My Bp was quit driveable,but i couldnt do 75 mph in 5th,it bucks like crazy !Running premix will help alot with reliability.If you decide to do it,make the bridge as thick as possible to help it last.

 

one thing I'm worried about is hills. bumper to bumper live with anything, i want to know what if your at a stop light on a hill?

 

I never pulled away at idle with my Rotary at idle,even when it was still street port.Take it up to 2000rpm,its not that high.Depends on the type of bridge you will have.Semi bp,or full bp,or j-bridge or monster..

If you want driveability,then rather only bridge the secondary ports on a 4 port,nice gains,while retaining gas mileage,and stump pulling torque!

 

ok thanks for all your help
I think im just going to port a S5 NA.

 

85 whp for a 1st gen 6 port? wouldn that be around 105 bhp? I thought they came with 135 or 140?

 

Your elevation above sea level makes a big difference.Some people prefer not to correct the figure to sea level (i prefer that)

I have seen pretty scary dyno figures : 280hp 12A peripheral port is one example i remeber clearly

 

I had 88 six port Bp engine (w 85 13b internals), Briddge in the secondary ports in my 85 gsl ran fine I smoked vetts, z's, ss impalas, m3, Even some TII's ran past stock 93. (wouldn't waist my gas on honda)
driven on the street every day fort laud to miami
full body (car minus alot of crap exept ac pw sterio)
I would say it had to be making 250 (w my setup)

RB Holley 550
RB road race dual exhaust to borala straight thru muffler
3 in 2 /2.5 out
dual pulleys
ultra wires
craine ignition and coils
17lbs flywheel