S5 wastegate porting
 

First off I've been searching and searching only find info on s4 wastegate porting.
Wanted to find out if there was a write up for it or is it essentially the same as porting on the s4. Also wanted to find out if it is going to be necessary.

The engine is a s5 jspec with all stock internals. I have opened up the exhaust so I was getting fuel cut. I do have an FCD on there, but thinking about going rtec. I just got 720cc primary and secondary injectors. Installed FMIC and have deleted most of the rats nest.

I do have a manual boost controller that I would like to install. How much boost can the stock wastegate handle on an s5? If I left off the boost controller will I be okay with the setup I have on stock wastegate porting? I know my boost gauge is inaccurate with the FCD one of the reasins I want to get the rtec.

woooah there! Porting is the same for s5 except you'll be dealing with two ports instead of one. This is definitely a beneficial step for any turbo fc. The stock waste gate is waaaaay too small.

Going with an rtek 1.8 will be the easiest with those injectors.

Throw that mbc on there and you'll be able to boost 10psi safely. Going up much more than that and the stock turbo is inefficient.

10 psi is fine. I just want to make sure I'm doing it safely. The rtec 1.8 is the one I was planning on getting, I got the injectors with that in mind. Just curious if it is absolutely necessary with the set up I have. I understand it is good to do, but currently I don't want to take the time unless I'm in danger of hurting my engine with out it.

Hey Josh. I would def port the wastegate! You can also grind out a 90*deg cornor in the hotside. Ian has it down pretty well and might help you.

I never ported the waste gate on my S5 turbo and have had no ill effects. On a stock S5 turbo its just not a necessity. Ive got a dp, no cat and an N1. Ive worked with quite a few cars with setups similar to mine, All S5 turbos and none were ported. They also had no problems.

This may help:

http://www.fc3spro.com/TECH/HOWTO/KWG/kwg.html

I am going to get off topic here for a second...I have a header back RB road race exhaust system on my 91 NA and on first and second gear when I accelerate slowly the car jolt.. is that the fuel cut that you are talking about?

you will know fuel cut when you feel it. its like hitting a brick wall

Thanks guys.
Fuel cut happens when you are overboosting. and fuel is cut to the secondaries I believe. Not sure if the NA has problems with fuel cut when you open up the exhaust and port, thought it was a turbo thing. Any ways when the fuel cuts out you lose power, you'll know it if that is what is happening.

Thanks Guys.. it feels more like it is stalling but as soon as I shift to the next gear it is all good..It mainly happens when I am slowly accelerating and I go over a bump.. I have to look more into it

fuel cut is from overboost. something your 1991 NA does not have.

ouchh..that kind of hurt lol