ludeowner

Hi guys,

I was planning on having my engine replaced by hopefully the middle of next year. One thing that I am having a hard time decing on is whether I should get a street-port or if I stay with stock ports. I was wondering if it would be possible to add restrictor plates on the intake side of the TB.

I tried looking for topics about restrictor plates in the intake. However all I found were topics about restrictor plates in the exhaust to prevent boost creep from MPs.

I was hoping to find some threads about people adding restrictor plates between the TB and elbow. I couldn't find any, so I was wondering if any one has ever heard of this being done to limit airflow so that you can pass smog. Or has anyone ever heard of restrictor plates in the exhaust helping out with passing smog testing?

Thanks

DaleClark

iTrader: (55)

Why would you want to limit airflow to pass smog? That's not logical.

The reason a streetport *could* have problems passing smog is the different intake/exhaust timing - you can get more overlap, diluting the intake charge, and possibly affecting emissions.

I can't think of a possible reason why an intake restriction would do anything emissions-wise.

I would moreso ask these questions -

- Has anyone passed smog with a streetport?

- Do I really need a streetport?

People have made a LOT of power with the stock ports - how much do you really need? You can easily get in the 300-350hp range with a stock port.

Something to think about .

Dale

r0t0r-rooter

If you want restriction in the intake stream, just put the stock airbox & paper airfilter back on. You'll need to for the visual part of smog anyways
I believe there have been several forum members who have passed smog w/streetports & hi-flow cats such as rynberg.

ludeowner

I thought that the additional power gained from porting was mostly from increased air flowing into the housings. I think I remember reading how porting affects your timing, but I didn't think that it was the main reason a street-port would fail smog. I figured that I would switch to my stock ECU and run a restrictor to limit the amount of air entering the ports.

I didn't consider a streetport until recently...I just really like the idea of an additional 10-20% in power that may be gained with a port. I also do recall people passing smog with a streetport and all the tricks in the book (alcohol, clean catch tank, plugs, oil, etc).

Just fo comparison how much do you think the following setup would yield. For the sake of argument at hand, lets say that I am able to maintain 12-13 PSI and that I have sufficient fuel, ECU and ignition upgrades to support the mods.

-stock twins & stock ports
-Greddy intakes
-Greddy 2-row FMIC
-M2 DP
-resonated MP
-Apexi GT CB

I'm guessing around 290-310 RWHP on crappy CA gas (91 octane). But what kinds of number can be expected if there was a streetport in that mods list as well?

sirjury

i believe pinneaple and shane racing both offer an "emmission friendly" street port. the restrictor in the intake would not help, it is the port timing that is critical for smog

rynberg

Hehe, not me. I've still got original engine and stock main cat. I did pass smog (by a mile) with the mods in my sig, with the stock ecu.

Max Cooper has passed smog with a streetport, hi-flow cat, and putting the stock pre-cat back on. Check it out under his hi-flow cat write up at www.maxcooper.com

There is no reason you can't tune the PFC to pass smog with a small streetport.

VeeTec

You definitely want the street port.