Hey, I have a quick question, and yes I did search around for the answer. Is it possible to run a Streetported N/A engine, and if so, what kind of power output should I be looking to get and what kind of intake setup should I try to run with it? So long story short, can I run my S4 intake with a streetport setup? I am also assuming that I would need to upgrade my fuel system also. Any input on this would be greatly appreciated. This is for an upcoming project I want to start. Thanks.

 

yeah i see how that wouldn't really pop up in the search.

yes you can run the stock intake and fuel system on a ported engine. if you look a kahrens dyno charts you'll see that he's done a good job of proving that

a. even a stock engine can make more power with a different intake manifold

b. a ported engine with stock intakes will make about the same power as the stock engine aftermarket intake.

c. the s4 fuel system has enough injector, but maybe doesnt supply enough duty cycle, although this seems to vary a bit car to car, and s5 certainly is richer.

d. the factory tune is a little, hmm well something like an rtek would be a good idea.

there is also a fellow in canada, with a ported 13b and megasquirt that is making big power on the stock intake, can't recall the name off the top though, racer23?? 45? something like that

 

Yeah, I made a rough guess of 160hp with a stock GSL-SE engine with GSL-SE intake manifold, with no sleeves, nice exhaust, yada yada. (Okay it was still the 12A midpipe but it wasn't the choke point at 160hp)

When I put together my four port (TII block) streetported N/A, I used the GSL-SE intake manifold because I was really pressed for time to get the engine on the road. No port matching whatsoever, I just bolted it on. Intakes are easy to change after you get the engine in and running... anyway, power did increase but only very slightly. Midrange torque improved a lot. When I put the TII intake on finally, midrange torque didn't change all that much but I got a lot more top end.

Paul Yaw got 210 wheel HP from a mostly stock Series 5 TII intake manifold. I'm about 30hp down on that, but given the manifold situation it has got to be a difference in exhaust setup and porting. Given the numbers other people get from the 6-port's intake manifold, my winter project is going to be modifying a 6 port lower to mate to the TII block. This is backwards from what most people do, but I'm not most people. I don't have a turbo in the way and I want to beef up my midrange torque.

I'm keeping an eye out for a Series 5 N/A intake, though. I have a RPM switch that I can use for controlling the VDI, assuming I didn't just want to use a GPO on the Megasquirt.

The N/A cars definitely have enough injector for 99% of the people running a stock intake manifold. I'm putting out a fair bit of power on two GSL-SE injectors, the FC N/A injectors can flow about 20% or so more fuel than that. Whether the ECU is willing to run to those kind of duty cycles is another story... I have heard that the FC computers simply will not go higher than 70%. I have no experience with this...

 

s5 intake is a good idea, they do work on the 6 port motors, the neat part is standing behind an S5 with an open exhaust, you can hear the 6 ports and VDI open, the tone changes twice.

i put a WB on my stock (except for afc) s4 car, and its not as rich as the s5's ive had.

 

The engine Paul built had a decent port on the secondaries but the primaries were only open up for about 10 more degrees of closing timing. In other words his intake ports were far smaller than many people here like to go. However his exhaust ports were absolutely gargantuan which is what made the difference.

 

I'm sorry, I think i understand, but if you run a S5 intake, and port the intake runners a little, but the exhaust a lot, it will make a good amount of power? When I port the intake on the irons, do I eliminate the separations between the ports? sorry to sound like a newb, but i just want to know if this would be worth the time and money to put into it?

 

Never polish ports.

 

No!!! Leave the wall there.

The engine that we are talking about that Paul Yaw built was a 4 port. It's a very different animal from a 6 port.

 

http://www.yawpower.com/sep2004.html

 

I think you may be talking about my old setup. It was an S5 Mazda ReMan 6 Port motor with a ported S4 intake setup and flowed throttle body. It made decent power (peaked at 184.1 rwhp) with the stock S4 ECU. I had a very trick exhaust on the car as well. It was very strong and actually lost power over 6,000 rpm when I switched to the S5 intake I had. What was cool is that it looked almost stock from the outside. I do know that other people have generated way more power with stock ECU's in Improved Touring cars so you may want to look that way as well.

What I am running now is an S4 TII set of irons with S5 TII housings and rotors. It has a mild 1/2 bridge on the outer irons with a crazy extend port on the primary ports. The exhausts are Racing Beat Race ports. For an intake I am running a self designed and crafted 4 port ITB setup with a Megasquirt. It took almost 2 years (part time) to get the car running well along with many runs down dead ends. Now the car flat out flies and is able to run with cars making close to 300 hp. I am going to take it to a chassis dyno shortly to see what we have at the rear wheels, but seat of pant's its really really impressive. I was getting tire spin going into 3rd using Toyo RA1's.

Eric

 

I was in a small streetport and big exhaust port on my na s5 and it worked very well for me. You wouldn't believe the cars I beat. When everything is working right, they can make a good amount of power.

 

yep!