rotarydelight

i just got my 88 turbo II running, and we put in a 3" turbo back to dual 2.5" exhaust. when i go to accelerate i think i get fuel cut. I plan to send r-tek my computer next week to get the r-tek1.5 put in as to eliminate the fuel cut, but is it still safe to run this much boost? my boost gauge gets maxed out when i go on boost (does anyone know what is the equivelant in psi?)!!! what about fuel mods? i just got this motor put in and dont want it to blow on me.

rotarydelight

? anyone ?

Alex-7

You need an aftermarket boost guage somethin' fierce.

evileagle

iTrader: (1)

Fuel cut is your cars way of telling you to knock it the hell off.

Don't rod on your car until you get the rtek, it isn't safe.

Alex-7

Return your car to stock boost until you eliminate fuel cut, if you have a boost controler (which you must) just puting on an exhaust wouldnt drastacly increase boost like that.

Stock. Then your rtek thing and a boost guage, then more boost.

evileagle

iTrader: (1)

With a straight-through exhaust you can spike the boost turbo well into boost cut without a boost controller. Especially if it's an S4.

Alex-7

Really?

About when do S4s hit fuel cut? (psi)

adrock3217

I think S4's hit fuel cut at 8.6psi? Correct me if I'm wrong.

But yes, with 3" exhaust and 3" intake, the stock turbo can get anywhere from 14-17psi.



As an edit...
With the R-tek, you will only get rid of the fuel cut. Unless you have at least 720 secondary fuel injectors, you need to NOT BOOST. The stock pump / injectors are not powerful enough to handle this kind of boost(over 10-12).

You should get:
720 secondary injectors; Walboro 255lph fuel pump.

Now at this point, the turbo is basically maxed out at 12/13 psi. Any higher, and the turbo is ungodly inefficent. It is blowing hot air, and making you less power then if you were boosting less.

You HAVE HAVE HAVE to port the wastegate. Have someone experienced do it for you (post about needing someone to do it..?) unless you are inclined to do it yourself. Also, the top mount intercooler is really inefficient higher then 11psi. You'd need a front/v-mount for higher than that.

tjeter

Port Your Wastegate, I Lost Compression On My Rear Rotor Due To Boost Creep. I thought i was going to be alright, but after time the seals eventually went.. rebuild next week... ugh..

evileagle

iTrader: (1)

The reason it's so easy to hit fuel cut isn't because of where the fuel cut is, it's because of the pathetically small size of the wastegate on the S4.