My t2 is going to be runnind a jspec motor, with 3inch exhaust from turbo all the way to the end. Intake... and 12psi. Stock fuel system and ecu. I know stock it is like 200 hp... fuel cut is 12 psi, correct?

 

No power at 12PSI and the stock fuel system since the engine will be blown.

You need fuel mods to support that power level. A higher volume pump, 720 CC secondaries and something to control them (ie. S-AFC). Also a FCD if using the stock ECU. 12 PSI is about where the stock turbo starts running out of push as well. Much higher and you'll be basically just adding heat.

 

Fuel cut is about 8psi... Once you upgrade to the 3" exhaust, you'll automatically need to get an FCD and port the wastegate as well, because the exhaust will cause your minimum boost to raise automatically, thus you'll hit fuel cut with the exhaust alone... Definately get at least an FD fuel pump, 720 secondaries, fuel programmer, and FCD if you plan on running 12psi... And you better max it out on the wastegate porting... And don't expect your stock turbo to last very long at 12psi either... Just look at my mod list... It's not all of them but it's at least a general idea of what you should have - the porting...

 

And a less restrictive turbo inlet duct will raise the boost as well... Keep that in mind...

 

Just wondering about the wastegate, is it possible to just buy a different wastegate? Someone told me that the wastegate is internal on the stockers, so is it possible to add a new one, or are you stuck with the stock one until you upgrade the turbo?

 

not nessisarely, my friend's car is stock besides the 3" to 2 1/2" duals with only two mufflers, and he only hits fuel-cut if its around 5 or 6 thousand in 5th gear. Although we ported his wastegate a bit too. Usually it only happens above 90 mph. even then its kinda rare. but fuell cut is nasty at 90 mph

 

Also fuel-cut happens at 9 pounds.

 

Well whatever... Regardless, with his intended mods, he would certainly hit fuel cut without porting the wastegate... With my mods the way they are, and my boost controller zeroed out, I'm running 9psi... And my wastegate is ported to 35mm...

Thanks for the correction on the fuel cut psi though... Knew it was somewhere around there...

 

You have to have a manifold that allows the use of an external wastegate... And it's really pointless to bypass it anyways, because with your wastegate ported to the max, it'll handle about what the stock turbine will anyways...

 

fuel cut is around 8 psi, you will also get alot of boost creep with stock WG, u will want to "port" the stock one heavily, and then use a manual or electronic boost controllor.

as for a stock fuel system at 12 psi the motor WILL genade it self!

if you have an s4 car id recomend an rtek 1.7 ecu upgrade with 720cc injectors, and a walbro 255 fuel pump, that will solve your fuel issues for what the stock turbo can push( about 12 psi max anyway)

id want to upgrade your intercooler running that high of boost as the stock one isnt very effiecent at that boost level, and heat can cause detonation!=blown motor!!

if you have an s5 or dont want an rtek then some sort of SAFC and larger injectors is still nessisary and fuel pump

 

Ok, well I took some of you alls advice and bought the following parts...

Air intake filter and adaptor
Walboro 255 fuel pump
Rtek 1.7 eprom
3inch exhaust turbo back.
720cc secondary injectors.
stage 3 6 puck clutch
Greddy blow off valve
some autometer guages to monitor all my fuel, air, and boost...

how do I get my wastegate ported? Is it easy to take off while the motor is in the car? Who an port it for me so I dont get any boost creep? I dont want boost creep.. I want it as stable as I can get it.

So, with all these parts on the car, would 12psi be acceptable?
what sort of hp should I expect(guesstimate)?
This is all the stuff I can and want to afford to put on this car.

 

It is possible, but it's not worth the performance versus the price.
An HKS 40mm or Tial 38mm is still at least $200+.
Then you need someone who can weld and custom fit the external wastegate onto the stock turbo.
Try do a search for a thread from BLUE TII...


-Ted

 

hey does this fuel cut feel like the car is pulling bacl for a qiuck sec ?? cuz if it then i have that prob, so alex hook it up with a fd pump and 720's lol. How much does the pump run ?

 

What RPM is it hesitating at?

You could be experiencing the 3800 hesitation... Just do a search on it if that's the case... And I'm afraid 720's and a fuel pump won't help you with fuel cut... You'll need to buy a fuel cut defencer for that... And besides, the only ones I have right now are in my car...

 

so what kinda HP should he expect with this setup?

 

About your wastegate, see this thread. https://www.rx7club.com/2nd-generation-specific-1986-1992-17/serious-s4-wastegate-porting%85-343788/
Thats what I plan to do on my..well my sisters :-P..new 87 TII later down the road.

also
when you get the money you could also get a BNR stage 2 which would be supported by those mods taht you would have done and increase the psi to a max of 15(which is also the max psi for rtek1.7)

good luck on your project