The Top Mitsubishi Galant VR-4 Resource

Join the best E39A 1991-1992 Mitsubishi Galant VR-4 community and document your GVR4 journey.

  • Software Upgraded - Reset Your Password to Login
    In order to log in after the forum software change, you need to reset your password. If you don't have access to the email address you used to register your GVR4.org account, you won't be able to reset your password. In that case, follow the instructions here to regain access to the forum.

2G MAS on 1G car

so i keep reading about this 2G mas on a GVR4 setup that is apparently reall good as an intake mod. the only problem is i dont understand what all is required to get it to work properly. different sites say different things are required. some say you just need the 2G mas and proper piping, some say you need a fuel controller, some say you need the maf translator. so can someone explain it? ive looked all over and just get more non-answers. what do i need to do this setup properly. is there a site that sells the entire thing, with everything needed, somewhere? like filter, mas, piping, fuel controller/translator/whatever, etc in a package?

i dunno if it helps to know or not but my car is pushin 15PSI with port/polished heads, turbo wastegate actuator disconnected, the idle bypass valve connector disconnected, and the heating/coolant lines to the throttle body removed. otherwise its stock cept new stiffer motor mounts and a boost gauge.
 

4orced4door

Moderator
Joined
Jul 19, 2002
Messages
9,846
Location
Raleigh, NC
Before messing with the intake (aside from a K&N) you may want to go with a higher flowing exhaust setup, then a fuel pump. You won't start overrunning the stock MAS until you've done this stuff and are running 18 or so psi.

Also, you might want to knock your boost down a tad if you don't have any sort of logging device (pocketlogger) to count knock. With stock fuel I consider 15 pushing slightly over borderline.

When you do get ready for a new MAS you have a few possibilities:

2G MAS with 550's, preferably with an S-AFC to tune it up.
GM MAS sensor with the ramchargers GM MAS Translator.
VPC with no MAS (speed density).

The additional flow from the 2G mas is fairly balanced out by the larger injectors. The GM setup has much less restriction and is simpler to install. The VPC has no restriction but your injector sizes are limited to 660's and under.

Additionally the VPC and GM MAS setups can be configured to vent the BOV to atmosphere if that is your thing (more top end, less torque, a lot more noise
grin.gif
).

Any of these setups will work best with a new intake pipe. Try www.dejontool.com for lots of different choices for each setup.

Hope this helps.
wink.gif
 

4orced4door

Moderator
Joined
Jul 19, 2002
Messages
9,846
Location
Raleigh, NC
As far as finding all the stuff in one place goes, you probably will have to piece it all together. You can buy the GM MAS translator, MAS, intake pipe, and filter from dejontool, but you can certainly get the mas cheaper at a junkyard and save yourself a minimum of $50.

With a 2G MAS you will pretty much be buying it off of another user or once again from a junkyard.

There really are not any kits because there are so many different ways to do your intake that most people never have an identical setup. You are best off piecing things together yourself.
 

what fuel pump do you recommend? ive heard the walboro 255 is loud but does the job. anyone know how loud it actually is? i dont want to hear it from inside the cabin.

and what would be a good exhaust setup? ill prolly go custom made instead of name-brand.
 

turbowop

Well-known member
Joined
Apr 29, 2001
Messages
11,971
Location
Yakima, WA
quote:Originally posted by Notorius:
what fuel pump do you recommend? ive heard the walboro 255 is loud but does the job. anyone know how loud it actually is? i dont want to hear it from inside the cabin.

and what would be a good exhaust setup? ill prolly go custom made instead of name-brand.
So far my car has consistently run high 12's/low 13's with the Walbro 190. It's not that noisy, but that's a matter of opinion, I guess. With the 255 you will need an adjustable fuel pressure regulator which makes it a more expensive upgrade. As far as exhausts go, good luck finding a name brand setup for our cars other than JIC anyway. Nobody makes one. A lot of people run a setup from www.certifiedmuffler.com which work well. I love mine. Good luck and have fun....
 

4orced4door

Moderator
Joined
Jul 19, 2002
Messages
9,846
Location
Raleigh, NC
I'm running a 255. If you stand outside the car it is quite loud, and you can even hear it in the car a tiny bit, but you would have to be super picky to care. It's not that bad, people just like to bitch about it. An AFPR is definitely a good idea for it though.

I've got a Certified Muffler 3" setup. It gets the job done.
wink.gif
 

quote:So far my car has consistently run high 12's/low 13's with the Walbro 190. It's not that noisy, but that's a matter of opinion, I guess. With the 255 you will need an adjustable fuel pressure regulator which makes it a more expensive upgrade. As far as exhausts go, good luck finding a name brand setup for our cars other than JIC anyway. Nobody makes one. A lot of people run a setup from www.certifiedmuffler.com which work well. I love mine. Good luck and have fun.... [/QB]how hard are you pushing the 190? is it nearing upgrade time if you wanted to go deep 12s?
 

turbowop

Well-known member
Joined
Apr 29, 2001
Messages
11,971
Location
Yakima, WA
QUOTE]how hard are you pushing the 190? is it nearing upgrade time if you wanted to go deep 12s? [/QB][/QUOTE]

I don't think deep 12's are out of the question. With the new intercooler on I'm hoping for mid 12's. It definately pulls harder and the 190 is doing just fine so far. My goal for the car is to get into the 11's. To do that my next step is probably going to be a PTE 50 trim turbo and to do that I will upgrade to a 255, adjustable fpr, and some 660cc injectors.
 

I would go with a 190lph, I have seen dsm dyno more than 450hp, with 660 denso injectors. And it was with a turbo bigger than a 50 trim garret. What ever fuel pump you go with, it is very important that rewire it.
 

i didnt do it. the guy i got the car from did it. ive known him for several years and from what ive seen no one in CO knows as much as him about VR-4s so im gonna trust his judgement. ill ask him about the ISC and see what he says tho. and yea, the wastegate is stuck open slighty. were fixing that and a oil return line leak sometime this week (prolly wednesday). and im ordering a hallman MBC as well.

i havent noticed spoolup time/rpms tho, ill check it when i go out for a drive today. what RPMs should i be expecting in relation to initial spoolup and full 15PSI?

*edit*
tested the car, got 15PSI at about 3900ish in 3rd gear with the car being warmed up.
 

Ian M

Well-known member
Joined
Jan 11, 2002
Messages
2,348
Location
Martinsburg,WV
3900rpm with a 14b is too high. Even with the stock exhaust,it should be around 3000 or so.

On my car with hogged out exhaust housing,3" exhaust,IC and pipes,ect.,it spools to 16 psi around 2700-800 rpm or so.

Exhaust makes a big differnce in spoolup,as well as a proper boost controller. A ball/spring controller like the Hallman (good choice) makes a noticible differnce over a bleeder type. Fixing that wastegate is going to be huge! If you have to pull it apart,nows a good time to do some porting..
wink.gif


I still dont understand disconnecting the ISC;no performance improvement there. Maybe it was bad, causing idleing problems who knows. If you still have AC,it might not be a bad idea to check it via the VFAQ,if it needs replaced,Gabor (Sleeper) rebuilds them,or you could try a junkyard one,even Hyundais use the same one.
 

quote:Originally posted by Ian M:
3900rpm with a 14b is too high. Even with the stock exhaust,it should be around 3000 or so.

On my car with hogged out exhaust housing,3" exhaust,IC and pipes,ect.,it spools to 16 psi around 2700-800 rpm or so.

Exhaust makes a big differnce in spoolup,as well as a proper boost controller. A ball/spring controller like the Hallman (good choice) makes a noticible differnce over a bleeder type. Fixing that wastegate is going to be huge! If you have to pull it apart,nows a good time to do some porting..
wink.gif


I still dont understand disconnecting the ISC;no performance improvement there. Maybe it was bad, causing idleing problems who knows. If you still have AC,it might not be a bad idea to check it via the VFAQ,if it needs replaced,Gabor (Sleeper) rebuilds them,or you could try a junkyard one,even Hyundais use the same one.
what would i port w/ the wastegate? im guessing youll say turbo in which case is 350$ for a 16G a good deal?

and for whatever reason ISC never registered in my head so i just skipped answering about it. i believe the reason its disconnected is to help keep the car cooler. ive seen some DSM guys say to disconnect it in the summer or before going to the track. i also know the domestic V8 guys do it to help their cars keep cooler, so thats my guess.
 

Ian M

Well-known member
Joined
Jan 11, 2002
Messages
2,348
Location
Martinsburg,WV
quote:Originally posted by Notorius:


i dunno if it helps to know or not but my car is pushin 15PSI with port/polished heads, turbo wastegate actuator disconnected, the idle bypass valve connector disconnected, and the heating/coolant lines to the throttle body removed. otherwise its stock cept new stiffer motor mounts and a boost gauge.
Im amazed no one has asked this yet but,WHY do you have the ISC and wastegate disconnected?

Disconnecting the wastegate is NOT the way to control boost! It sounds to me like you have a cracked exhaust housing/leaking wastegate flapper,cracked manifold,boost leak,ect limiting you to 15 psi. Otherwise,without a wastegate,it would boost way past 20 psi. You need to figure out what's going on there and install a proper boost controller! Id bet you would see a big improvement in spoolup and power too.

I dont understand the purpose of dissconnecting the ISC at all.
confused.gif
Please enlighten me..
smile.gif
 

Notorious, i think you have the IAC confused with the fast idle control valve which has coolent lines connected to it. Removing these lines can theoreticly cool the intake air temp by eliminating the hot antifreeze from circulating through the throttle body (although if your EGR is still connected it benifits you BCS antifreeze temps are cooler than exaust temps, alot of people don't realise this). The ISC just allows more/less air through the intake to regulate idle, a/c on, stuff like that.

Also, I myself am in the proscess of converting to a 2G sensor. I admit the info out there is so confusing, i.e. some people love the 1G ported, some love the 2G meter, and some say screw em both and get a MAF translator. All of these people argue for or aginst their method and you don't know which way to turn. From my research (only my opinion) the 2G seems the way to go. Just buy 550cc's and you are almost tuned perfect right out of the box. The 1G ported is plaigued with problems from idle serge to MAS overrun, and the MAF translator (my origonal intended route) seems to be plagued with software problems (Their are tuns of sites with people who have it rippin it a new one, saying their car runs like crap and so forth). Whatever route you choose, Good Luck
 

Ian M

Well-known member
Joined
Jan 11, 2002
Messages
2,348
Location
Martinsburg,WV
You can port out the inlet of the exhaust housing and the outlet (collector) of the manifold. Factory,there is a fire ring that gets left out when you port. the resulting ridge in the manifold and turbo gets removed when porting. You also smooth out the short turn radius of the runner as it drops into the collector. If your manifold is cracked-and it probably is,a 2g unit is an upgrade.

Porting the wastegate flapper hole (enlarging) helps with boost creep,once you install a larger exhaust.

You can port the o2 housing out also.

Check out http://vfaq.com There is a good porting VFAQ on there,as well as pretty much anything else you can do to one of these cars.

If its a good 16g,yeah thats a pretty good deal! It may or may not be already ported,either way if it has a 7cm housing (it should) ) you will have to port the manifold to match the larger opening in the 7cm housing.

Actually,all the ISC does is bump up the idle when the AC compressor kicks on,ect. Its basically a valve that opens or closes by comand of the ECU to allow air to bypass the butterfly and control idle speed. All its going to affect is idle quality. You can have it hooked up and functional even with the coolant hoses to the TB bypassed.

The bypassed coolant hoses IS considered a free mod,however some folks experience with it vary. Some folks dont consider the decrease in idle quality on cold starts worth it,theres a pretty small gain to be had,its a personal choice thing .
 

The 2g MAS upgrade was one of the best things I've done to my GVR-4, but I'd have to rank it down the list, at least 3rd or 4th. The best 2 upgrades you can make is the exhaust work others have mentioned, and a larger intercooler and pipes. Those 2 things are the biggest restrictions, and you won't see much performance improvement by just upgrading the MAS as long as those restrictions are in there.
Even without hacking, the 1g MAS is good for >300 HP. There are several advantages to using the 2g MAS:
1) along with a Dejon(or other) shortened hard intake pipe, it makes a VERY low restriction intake system.
2) along with 550's it will push fuelcut off another 18% or so.
3) its a tried-and-tested system, without any of the tuning headaches some guys are having with the MAFT.
Another option, that I personally would like to offer, is running the 2g MAS along with 450's and a special chip I can make with the 2g MAS compensation in it. It should fire up, idle, and run just like it was made for our cars.
On a related subject: is there anyone on here still running a 1g MAS, unhacked, with stock 450's, and a datalogger? I would like to know what your fuel trims look like. Any input from you guys would be appreciated.
Most of my R&D lately has been focused on tuning the 2g MAS to work 100% without an AFC, and I'll be looking for some more guinea pigs to test these new chips on shortly. I will be including injector deadtime and pulsewidth correction for larger injectors too.
 

ken inn

Well-known member
Joined
Feb 23, 2001
Messages
7,529
Location
krum texas
i dont think the 2g mas/550's is an exact fit. yah, if you like loose clothes. at idle and up to about 2k rpm, i bet the ecu goes open loop cause it is too rich. on my afc, i have 1k at -13, 1.5k at -6, 2k at -2. at wot, with 560's, i had +4 up to +7, inj duty cycle was at 87%, i was getting 3 knock, and only 23 timing. before the 264's my 1k was -17. i also have the screw backed all the way out. the water injection killed the knock, upped the timing, and brought the afc hi settings to 0, dropping inj duty cycle down to 76%. the car runs much better with the 2g mas, and i am getting better fuel economy. same thing with the fuel pump. you CAN run the stock fpr with the walbro 255, but it dont run as well as it can if you have an adjustable fpr.
 

Ian M

Well-known member
Joined
Jan 11, 2002
Messages
2,348
Location
Martinsburg,WV
Definately IC pipes are a big improvement in these cars,drivability and power is WAY better. My 14b car made a 5/10th,5 mph improvement (13.50s@ 100-12.96@105)with just pipes and IC at the track too. Another freind of mines GVR4 made a 3mph,4 10th improvement as well,both examples are with just a 2 1/4 pipe,Starquest IC setup-even a budget setup can yield big gains.

Like Keydiver said,The 2g mas/AFC is the way to go IMHO unless your going VPC (more $$$)-once the other restrictions are taken care of. Its proven to work. I recently got around to moving my battery and making the switch from a unhacked MAS and 450s,drivabilty and power seems to be better,we'll see what happens at the track..
smile.gif


Jeff,My fuel trims usually varied from 100-110% with the unhacked 1g mas (screw backed out). I dont know if that is specific enough to help you or not..
smile.gif
 

quote:On a related subject: is there anyone on here still running a 1g MAS, unhacked, with stock 450's, and a datalogger? I would like to know what your fuel trims look like. Any input from you guys would be appreciated.Jeff I can get you my fuel trims if you want. I just went through smog and passed and want to keep the car stock for the time being since I have no hood on it. This is with the only mods being a cat back (2.5"-3") and JDM 2 1/4 IC piping and modified Starion IC. Last I checked they were in the mid 90's to low 100's .
 
Support Vendors who Support the GVR-4 Community
Boosted Fabrication ECM Tuning ExtremePSI Fuel Injector Clinic Jacks Transmissions JNZ Tuning Kiggly Racing Morrison Fabrications RixRacing RockAuto RTM Racing STM Tuned

Recent Forum Posts

Top