I'm thinking of starting a new build once my 2 rotor is running again. Something to build up while my car is running ...

I have always been fascinated by N/A 20b's. But to make any "real power" out of them you need to do either a very aggressive street/race port, BP or PP. Now for fabrication reasons PP is no go.

Lets say I built a 20b with 9.7-1 rotors and a large street port of half bridge. How long, realistically would the engine last in while being used for track duty? I've read that PP engines chew up seals pretty good over time. Is this the same when it comes to a 20b?

Please don't tell me to search. I've read nearly every thread in this subforum starting from "the beginning"... .

 

anywhere from 5 minutes to 5 years.

to many variables: engine builder, seals, clearences, tuner, fuel type, type of racing, ect. ect. ect...

theres no way to guess it... just do it.

 

Not quite the answer I was looking for, but OK.?

 

You should be just fine for a long time, I know several 20b owners locally and they have no issues and there running big turbos. The key is the oil and water temps and of course the tuning

Here is a sweet FC:
http://www.youtube.com/watch?v=MurqHkI148s

Probably my next build once my FD is just the way I want it......

 

sick!!

 

Since were talking NA, mechanically how well the bridge porting is done is going to be the biggest factor in long term reliability. A bad port will quickly damage the side, corner seals, and plates.

 

you missed the point of my post. Its not the answer your looking for because there is no answer. re-read my post and give it thought...

 

in addition to the usual things (coolant temps, oil pressures, maintenance, etc.) that should be done for longevity, addressing the porting/assembly issues that T-von mentioned will go a long way to keeping your proposed bridge, and you, happy for a long time.

 

Just maintain it. Theres no reason for things to break if you keep them in tip top shape.
If you go out and beat the tar out of it, then park it for the night. Sure, things will go bad. But if you take it easy, and if you do put your foot down, know what the motor is built to do. then double check all your fluid pressures and temps. Make sure all your hoses are tight. Get it tuned a couple times a year to be sure everything is running smooth. And replace things when the need to be replaced, it will last a long time!
The 20b was a production motor. Its not some crazy special racing only motor.
Porting it is like doing a big heads and cam setup on a V8. I daily drove a stroked 557 ford big block all summer. Running 12.5:1 compression. And It was perfect. Over 200 miles a day for 3 months.

Just maintain everything, and theres no reason for things to break.

 

How would a pp intake tear up seals, when the stock exhaust port is a PP. PP as far as I understand is very durable... more then a bridge

 

The ports themselves and their locations aren't the issue. The damage is done when the port work is done poorly.