bobbydigital450

This may sound a little out there and maybe it belongs in the turbo forum.... but either in may or june im taking my car into the local shop to start on a turbo project. In order to save money on labor, im doing what I can myself before taking it into the shop. Since im going to be replacing the vtc's I would like to go ahead and put in the 370 injectors while i have everything apart. So the question is.... how will my car react with the bigger injectors and everything else stock? and what happens if i throw a bigger fuel pump into the mix? Just curious and trying to save a buck or two and would rather drive it then tow it. any input would be appreciated.

Mizeree_X

iTrader: (9)

You will run pig rich. I don't think you'll even be able to start the car unless you adjust the idle FP, from what I've read.

bobbydigital450

That is what I was thinking, but I don't know enough about it to even guess.

Matt93SE

iTrader: (44)

yup.. get an adjustable FPR and set the pressure quite a bit lower.. like around 25psi.
should be able to at least get the car running for the time being.
the larger fuel pump won't affect anything, since they always pump more than enough and the FPR blocks the return line to the tank in order to build system pressure... thus a larger pump isn't going to hurt anything.

bobbydigital450

Would you recommend driving the car a great distance like this?

Matt93SE

iTrader: (44)

tune it first...
you may have to adjust the pressure up or down a bit.. dyno time will tell.

bobbydigital450

awesome... thanks

Brad92SE

iTrader: (9)

Yup, what everyone else said. The Nismo FPR for an SR20 motor is a nice regulator, it bolts up right in the stock location. Also, you probably want to invest in a wideband O2. You wont need to dyno then. Good luck on your project!

Matt93SE

iTrader: (44)

The ECU won't know what to do with a wideband O2. it looks for high or low voltage, nothing more. you might be able to personally tune it with a wideband and a gauge, but I wouldn't recommend doing it yourself on the street. MUCH easier to put the car on a dyno and have someone driving on the dyno while you reach under the hood and tweak it until the A/F is perfect.

Brad92SE

iTrader: (9)

Thats true, I was just referring to a stand-alone type of wideband, like PLX or an LM-1, not replacing the factory O2. Tuning on the street isnt that bad, as long as you have a passenger reading the wideband. Only thing is you dont get the nice graph as you would with a dyno, so it would be hard to tune an SAFC or the like in the midrange rpm's.

Maxpwer

iTrader: (7)

Like some have said, you can put an adjustable fuel pressure regulator on there and lower the fuel pressure, but you should ALSO hook up your AFC (and dyno tune it) or have JWT program your ECU (no tuning required, and despite the higher intital price, the way to go for a turbo IMO)

MrGone

iTrader: (30)

Wouldn't be too hard. You just have someone else drive. The SAFC gives you throttle readings so you know that they are completely WOT, also you can tell when they are using 18-25% throttle for cruising. Most 'stand alone' wide bands actually allow you to log it on your computer which is perfect if you dont want to have someone else drive/tune.

bobbydigital450

That is what I initially thought of going with, but from what I've heard, jwt doesn't account for altitude.....and im just curious if it's going to run worth a damn when i get my car back out here in denver...5280ft elevation...

But ultimately, jwt ecu, 370cc injectors, z32fuel pump, z32 maf.... it should be straight to drive a great distance with out turbo installed?

thanks for all the info guys

oh and brad...how are things comin along for you? did you finally get everything tuned up?

MrGone

iTrader: (30)

I would get an SAFC and wide band and tune accordingly. The SAFC will also help in hooking up the Z32 MAF.

Brad92SE

iTrader: (9)

JWT also tunes their ECU's very conservatively. You would be better off just to tune the car yourself.

I still haven't tuned at WOT yet, waiting for a wideband that works. Right now I'm in the process of rebuilding my tranny (input shaft bearing).

Matt93SE

iTrader: (44)

with fuel injection and MAFS, you don't need altitute correction.
the MAFS measures the air going into the engine by mass (thus the reason it's called a "mass air flow sensor"), so it doesn't matter if the air is thinner than down here at ~50 elevation.. if you have 50 grams of air going into the engine at once, you're going to need 3.6 grams of fuel to burn it. (14:1 ratio)..

bobbydigital450

very mixed opinions... matt i understand what you are saying about the mafs. makes sense.

My main concern is just getting it set up to where i could drive from burlington, iowa to denver,co without any problems. I'm not exactly sure how good I would be at tuning, specially without a dyno within 200 miles and It's something I really don't want to jump into without knowing much about. If I have to, ill install the injectors in the parking lot of the turbo shop, but I'd really hate to pull all that stuff off twice...and I'd even hate more to be paying someone to do something I can do myself.

Jeff92se

iTrader: (82)

Then install the injectors after. It's not hard on a VE. Just have to take the upper manifold off, remove both rails and swap injectors. Sounds like the risk of the long drive outweighs the convienence of having the shop do it.

In fact, this is what I'd do. Get a spare VE fuel rail(s). Put the 370s in with new 0-rings. And when you are ready, just swap rails with new insulators and you are done. A few hours and that's it. A FPR and a SAFC is needed to trim back the injectors though.

bobbydigital450

Yeah Jeff, I think you are right. RISK > CONVENIENCE

Ive had all of that off before when i did the variable intake swap during the 5 spd conversion so I know its not rocket science. But MAN, i'd hate taking all that shlt apart 2x (1. vtcs 2. injectors) damn it anyway

thats not a bad idea really tho with the fuel rails and what not, then id have everything ready to go and just pop them bad larry's in. great info,advice and ideas as always
thanks