hi guys ive my gvr4 for about 9 months only been drivable 3, but i just did the timing belt and got it running running again, but i noticed it had pretty much no power over 4000 and putted but i hear the boost swoosh,no boost gauge tho but after all the bars are lit on dash it keeps getting louder. so i found out that i have the evo 3 big 16 i forgot the numbers but it had 47 between the numbers that stick out. ohter mods are bc cams stage 1 im told, 2 1/2 to 3 inch turbo back. my queston is i just bought evo 560 injectors and a walbro 255 with re wire kit and will adding those with out some fuel controll like apexi s-afc make it more driveable in the mid range and stop what i think is fuel cut or pulling timing? maybe one or the other untill i get the s-afc??? thanks for all help.

The big question is what is being used for boost control? A boost gauge is basically the first mod you should do. Buy one, and find out what boost you are running.

I'm running an EVO 3 16g and 560 injectors with a walbro 255 right now with no air fuel controller (have DSMlink on the way). My car runs suprising well as it sits. I've also got a 2g MAF which I was running with the injectors before I got the 16g installed. Do you know if you're still running the stock MAF?

im pretty sure it is stock MAF, how can i tell if it is 2g?

Is the air filter in the stock location? If so it's probably not a 2G Also, the 2G MAF will have the number 609 on top of it if you have one. If you don't have a 2g I'd look at picking one up from someone for cheap. They're usually for sale on here and iceman69510 makes adapters to plug into the stock wiring. There are some good threads on installation lurking around here as well.

It likely won't make your situation better. You really need some way to control the larger injectors, either chip ,safc or link. Not that it isn't a good idea to upgrade the fuel pump though. Especially with larger injectors.

Do some searching on the visual differences of MAFs, it's very easy to identify.

His injectors aren't installed yet, they aren't the issue. It sounds like fuel cut from too much boost to me. The OP still hasn't answered what is going on in the boost control department.

And both the injectors and MAF will need tuned for, and just tossing them in there won't help anything. Did I mention you need a boost gauge?

+1 on getting a boost gauge

Also, it might help if you send us a pic of your engine compartment. Also, what kind of boost control is your turbo hooked up to?

Quote:
His injectors aren't installed yet, they aren't the issue



I was answering this question;


Quoting Gvr41415:
my queston is i just bought evo 560 injectors and a walbro 255 with re wire kit and will adding those with out some fuel controll like apexi s-afc make it more driveable in the mid range and stop

Actually, let me take a step back. Whatever you do, don't put more mods on it. Let's figure out what you have, what condition it's in, and why it's not working FIRST. Then, if needed or desired, you can continue with mods.

We need to establish exactly what parts you have on your car, and how they are functioning. For example:

Exactly what MAF you have.
What ECU you have.
How your boost control is setup.
How much boost you are running.

Jason, you are correct sir, I am an idiot. I'm still waiting for my coffee to kick in.

OP, I have a couple cheap boost gauges laying around. One is a Faze, and one is a Sunpro. $20 and $10 shipped respectively to a fellow .org member.

Quoting mtbmafia:
If you don't have a 2g I'd look at picking one up from someone for cheap.



Running a 2G MAF requires modifying the intake pipe to make it fit. If you run an EVO8 MAF, it fits the stock intake pipe without any modification.

Not to mention that the EVO8 MAF works better and can read higher HZ than the 2G one.

There is something wrong. Don't throw more parts at it until you diag the current issues. Your description does not sound like fuel cut to me. It sounds like boost/intake leaks causing the car to stumble. If you are hitting fuel cut the car would run strong and powerful at 4k and then have a violent power loss up higher. Could also be fouled plugs from running too rich due to the walbro pump that is already in the tank from the previous owner (same guy who snuck that 16g in there and never tuned it).

Check for boost/intake leaks both before and after the MAF. Inspect the pump and injectors. They might already be aftermarket.

Quoting Gvr41415:
hi guys ive my gvr4 for about 9 months only been drivable 3



Welcome to Galant VR4 ownership! You'll get used to it. /ubbthreads/images/graemlins/grin.gif

the injectors are blue tops

just added a boost gauge teed in right out the fitting in compressor outlet. what i know is it has stock ecm, stock maf, stock blue top injectors and pump but not sure about pump, stage 1 bc cams, 2 1/2 turbo back with 3in cat, and 16g. the boost hits 7psi @ 3500-4000rpm then loud putt-put-put (almost like launch control) no power right when i hear loud spool, shift up boost gauge jumps to 10-11psi. going to pressure leak the intake side 2morrow.


i tapped into this hose for boost gauge\/

not letting me add pics.

Tap into the vacuum line at the fuel pressure regulator. It's much closer than routing it around the engine.

Get a boost leak test done. A bit early for cam upgrades.

oh yea looks like no boost controller either