RotaryMan88

After I get my motor in and tuned properly...I was hoping to be able to boost around 10 to 11 psi..will the stock ECU allow this? How high will it let me go...
..I'm not concerned w/ fuel cut either...I already have the FCD...

Icemark

the FCD on a stock ECU should let you go up to about 15, but much more than that and you will want to replace the stock ECU (and everything else that you blow up, like Apex seals, etc).

fcturbo2

Yeah i heard stock ECU and fuel pump is limited to 15psi. Dont take my words for it though. I would stay between 9-12 psi just to play it safe.

BogusFile

I dont think it would be such a hot Idea to run it up to 12-15 pounds of boost on a stock fuel pump, stock ecu, and fcdestroyer.
Not to mention the stock intercooler. Crazy drunks!

RX-7 GT

hmm hmm good

1990 FC3S TII

HEY!

DO NOT run more than 10-11 psi with your stock ecu. Your IC only works properly till about 10psi. No "stock" Turbo II should run abouve 10 psi with out the proper fuel upgrades (HKS F-con upgraded fuel map, high flow fuel pump, injectors etc...) Take my wod for it, I've blown engines in the past running the setup you mentioned. Use High octane gas, keep the boost below 11psi....better safe than sorry.

BLUE TII

iTrader: (9)

As you know, the FCD will fool the ECU into thinking you are making under fuel cut boost and you will have to make up the extra fuel for whatever boost over this level you are running or it will go lean and pow... It is not a question of how much boost the stock ECU can handle, since by adding the FCD you have bypassed the ECU on anything over fuel cut boost; the question is can you safely run a higher boost despite the ECU.
Yes, if you rewire the fuel pump and put in a high flow pump (like Walbro) you can run safe at higher boost, but will be running rich in the low and midrange (like catylitic clogging, eye watering, slightly reduced power rich.)
I run an 87 TII w/ downpipe/midpipe, TID mod, ported wastegate (keep the boost down) and Walbro and it runs 8:1 to 11:1 air:fuel at idle, 10:1 to 11.5:1 in midrange (7lbs boost) and 11:1 to 13:1 at full 10 lbs boost (13:1 is on a cool damp night at redline in 5th.)
Running rich isn't the best, but is safer than lean. If you have 87-88 be sure you port wastegate before you uncork the exhaust/intake too much or you will get way too much boost.

RotaryMan88

Well here's my idea...
..I have the 87/88 GTR T2 motor...but I'm getting the 89+ Turbo and manifold with it. I'll be running 720cc injectors, fuel controller, FCD, 2.5" exhaust(no cats), boost controller, Greddy BOV, and I'm going to add a popoff valve to control my boost from going over 10PSI....with all this, I think I should be safe, but is there something I'm missing? Oh yea, I have ordered a Walbro fuel pump too....

BLUE TII

iTrader: (9)

sounds like you will have plenty of fuel for 10psi and can tune out the richness in low and midrange w/ the fuel controller. If you put a TID mod on you won"t need the boost controller to get 10psi (although I guess it might help the midrange some by keeping the wastegate closed tight till 10psi). The TID mod really helps turbo response and gives you the great intake/blow off valve noises.
Make sure you aren't always relying on the pop off valve to regulate boost, you are losing metered air. It is designed to be a precaution against a failed wastegate/wastegate line etc. I guess if you set it up as a bypass valve that put the excess boost back into the system infront of the turbo it could work as a boost regulator, but this would heat the air charge excessively at the high boost just where its worst anyways since some air would be going through the turbo repeatedly.