evo3 turbo question

chengsta · 08-06-2006

I'm planning to upgrade my stock t25 to an EVO3 BIG16G and was wondering if I should get the 34mm flapper upgrade even though my car will be a daily driver and will most likely not exceed 20psi. I've search all over to find out more about going with the 34mm flapper route but it still got me stumpted since some people say go for it while others say its not needed.

Mods I have my car: '99 spyder gst
-tsudo n1 3inch cat-back exhaust
-hard upper and lower intercooler w/ recirculated monza SSQV
-hard intake
-boost & air/fuel gauge
-apexi SAFC
-megan racing 3in downpipe in the box and ready to install when i get the turbo

I have the rest of the supporting mods coming in.

**JET** · 08-06-2006

Contrary to what some people believe, a bigger wastegate is need when you are running LOW boost, not high. The wastegate is what regulates boost and must blow off excess exhaust gas so that higher boost is not attained.

I am not a huge fan of 34mm flappers, you can get an even better effect with just porting the stock sized flapper.

95talonracer · 08-06-2006

Just port the stock flap opening out. I did it and it works perfectly at 18-20. Your best bet.

chengsta · 08-06-2006

Alright thanks for the info. I'll just port the flapper myself and save some money

Shane55113 · 08-07-2006

I have the 34mm flapper on my evo3, i also have the hot side ported and the evo3 02 housing ported, i dont creep

Elementality158 · 08-22-2006

I have an Evo III Gt turbo. I just bought the car and i am wondering if something is wrong with the wastegate. Im hitting about 19 psi with the stock boost controller. I am also hitting really bad fuel cut at about 4 grand.

npaulseth · 08-22-2006

It's an evo III GT? If so, that's the china made knock off turbo and I wouldn't be suprised if the wastegate is broken. That's why you are hitting 19 psi if you aren't using a MBC. I'm assuming the wastegate arm isn't adjustable?

**Kracka** · 08-22-2006

Quote:

Originally Posted by Elementality158

I have an Evo III Gt turbo. I just bought the car and i am wondering if something is wrong with the wastegate. Im hitting about 19 psi with the stock boost controller. I am also hitting really bad fuel cut at about 4 grand.

You may be boost creeping really badly, do you have at least a ported o2 housing and full turbo-back exhaust?

Elementality158 · 08-23-2006

Im not really sure whats up withe the o2 housing or the exhaust. Ill have to look at it. The car is so slow right now and has fuel cut at about 4500 rpms. I can check everything tomorrow. I can try another waste gate tomorrow. But i need to figure out whats with the fuel cut. I think its something with the intake. help me out!