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check these logs, found knock

I know I suck. I can't believe that I didn't look closer at the 450/550/660 chip fiasco. I hadn't planned on tuning the car myself, but I'm just tryin to make do with what I have right now. Sorry guys for making three different threads abotu what is probably the same issue. /ubbthreads/images/graemlins/banghead.gif

Quote:
Get a keydiver chip for your 660cc injectors, and get a 450cc chip for your vpc. ...



Wouldn't I want a 660 chip for the vpc to match the 660 chip in the ecu?

Yes I know what KISS is.

As for .88-.92 you talking about o2 volts, correct?
 

Quote:
Wouldn't I want a 660 chip for the vpc to match the 660 chip in the ecu?


No. HKS never made a 660 chip, for good reason. The whole principle the VPC uses to reduce injector pulsewidth is to lie to the ECU about the airflow. You can only do that so much until the airflow Hz is so low that the ECU is way off on the timing maps, causing huge knock issues.
Buschur took the VPC550 chip and modified it to 660cc FOR RACING ONLY! It will only work if you're running some very high octane racegas.
 

Champ_168

Well-known member
Joined
Dec 17, 2004
Messages
127
Location
IL
YEah o2 volts.

As for the chips, do it exactly the way I described.
Keydiver explained one of the main reasons why you dont do it the other way around.

The way I described would give you a better baseline. Maybe get some bigger injectors while you are at it. dont forget to use the proper keydiver chip for the proper ecu

So when you do all that, make sure the VPC is zero'd out...
and use your SAFC to tune the car.

Only thing to mess with on the vpc if anythign at all is the GAin knob. that will help out your idle, but do it in small and slow turns. Do that only if you cant adjust the idle with the safc.
 
Last edited:

Ok more dumb newb questions.

I don't need to have an AEM EMS to have their wideband gauge, do I?

So if I ditched my gay blinky air/fuel ratio gauge that doesn't do squat and got a wideband I can basically use that gauge and my logger to achieve a .89 o2 volts across the range, right?
 

strokin4dr

Well-known member
Joined
Aug 30, 2005
Messages
2,770
Location
Savannah, GA
Quoting Mike_1101:
So if I ditched my gay blinky air/fuel ratio gauge that doesn't do squat and got a wideband I can basically use that gauge and my logger to achieve a .89 o2 volts across the range, right?




Yes and no. The wideband's display will not be shown in volts; it will display the actual air fuel ratio. You will still be able to read your "o2 volts" that you speak of if you keep the narrowband o2 sensor or if that particular wideband setup allows you to program its outputs (my lc-1 for instance does). But the point of installing the wideband o2 is basically to eliminate the need of looking at stock o2 volts. The wideband tells you that information and much more.
Even though I have had dsmlink and been into 4g63s for quite some time, I have more experience tuning on load based systems such as the one I run in my turbo Civic, that are not as prehistoric as my dsmlink. I still have a narrowband 02 on the car but have not used it in a while; it really is not needed anymore. The point of this is that with a wideband, you do not have to run closed loop at all and can actually setup the car to run smoother and more efficient than it would off of the stock presets and just looking for that magical .89v from the stock o2 sensor.
 

Ok guys I finally got around to spending some time on the car. I tested the isc and it was bad, ordered new one and installed. Fired car up and it sounded the best it has since I've owned it. Seemed like it idled like a normal car. Cold so revs were at about 1600-1800.

After idling about 5 or so minutes, temp needle at half way point, shut car off, hooked up timing light, started car and it started being a bitch again, irratic idle and I have to put my foot on the gas to keep it from stalling. WTF it was fine 10 minutes ago. /ubbthreads/images/graemlins/banghead.gif Also, when I do put my foot on the gas it hesitates, then catches and revs go up. Whats up with that? If I let off the gas idle drops to 500 or below, almost stalls, catches and idles up, drops again repeat.

So I go to use the timing light and I don't see a line floating anywhere near the btdc marks.

Any other suggestions? I'll check it again later tonight when I get home and its darker out. This engine is ready to tell me to f off I'm sure.
 

Sounds like how my car was behaving after I forgot to hook up a spark plug cable and it was running on 3 cyl. Check your ignition system connections/condition.
 

Thanks for the heads up, will do.

Right now I have the UICP off so I can get at the TB. I bought a 15 dollar block off plate for the EGR and I ran a test on my TPS last night and heres the readings I got:

Closed throttle pin 1-4 = 4.89 ohms
Closed throttle pin 2-4 = .9 to 1.1
Opened throttle 5.09 tapering to 5.04

Not sure what this means but based on vfaq I need a slight adjustment clockwise.

Next I will quickly check injector ohms. After that assemble block off plate and UICP and start car to check FPR and set base timing.

I have a feeling the problem is my FPR or my ignitor. Is there any way to test my ignitor like I can test my IAC? With a multimeter? Could maybe be my fuel pump or a fuel filter. Maybe clogged injectors.

Oh, gonna check my o2 sensor as well.

I have been researchinng a lot and trying to narrow down possible problems so I can get this car to idle properly. Then I can drive it and mess with the safc. Speaking of which, I did add about 5% fuel and I did set the vpc back to zero (all at 12 oclock).
 
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