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.

Will a #501 MAS choke a Evo 3 Big 16g

conquesttsi

Well-known member
Joined
Feb 4, 2009
Messages
209
Location
Northern Connecticut
My girlfriend and I are each building b16g cars. This came up in discussion today and I thought I would see what you guys thought. A 501 mas is rated at 210 liters/second, converts to 445 cfm. I figure the b16g's efficiency is exactly that...445 cfm. Would a 501 mas get overrun? I think there is a good chance it will. I was reading somewhere that the b16g maxes out at 550 cfm, not efficiently of course. If that is true I think even the 240 liter/second (509 cfm) mas could get over run. Thoughts?
 

conquesttsi

Well-known member
Joined
Feb 4, 2009
Messages
209
Location
Northern Connecticut
I forgot to mention the reason the 501 mas came up in discussion is because of it's .78 psi loss over the 2g's almost full pound of boost, even though it flows slightly less.
 

thecman02

Well-known member
Joined
Nov 3, 2007
Messages
917
Location
Kalamazoo,MI
I'm sure someone will come in here with the correct knowledge. I could probably find the answer but I'm at work. I can tell you that 3g/evo MAF is good for 500hp so If you want to be on the safe side I'd get that MAF.
 

conquesttsi

Well-known member
Joined
Feb 4, 2009
Messages
209
Location
Northern Connecticut
Thanks but I am not sure how horsepower comes into factor in reguards to air flow rates. The problem may be null anyways because when I accually got home to look at her mas it says 165. I am not even sure what that is..time for more research.
 

ktmrider

Well-known member
Joined
Sep 10, 2007
Messages
3,128
Location
Tempe, AZ
I'd PM Jeff/Keydiver, he'll likely have the 411.
Edit, got bored here ( working nights ) and found these links:

click = post #11 shows a bunch of applications but not the 3K VR4 tho. Also has the maps for conversion so you can look at them side-by-side.

click = This link has more info, look at post #14 for Jeff's input.
 
Last edited:

punisher

Well-known member
Joined
Aug 13, 2006
Messages
284
Location
Chandler, AZ
3kgt vr4 has a "165" maf, which is identical to a 2g "609" maf. SL models had the "055" maf which is also equivalent to 2g.

The 501 is similar to a 3g and later evo except the plastic around the honeycomb is more restrictive hence the less airflow. The 501's came on newer Galants and Diamante's.

The Evo "399" maf is the highest flowing factory maf. The 3g Eclipse "482" takes a close second in airflow .

Higher flowing mafs are available and reasonably priced, so why try to run a smaller on at its max? Having room to make more power is always a good thing.
 

Street Surgeon

Well-known member
Joined
Mar 3, 2004
Messages
941
Location
Omaha, Nebraska
I've "heard" that by removing the "air horn" on the 501 MAF's that it will flow very, very close to what the 3G/Evo maf's do. As mentioned before I'm sure Jeff can verify.
 

Yes, the huge airhorn is what makes the #501 flow different than a #482. Many guys just rip it off and glue the screens in, but I would prefer to build up some facsimile of an airhorn to smooth the airflow coming into the MAS. Just don't try body putty. I tried it and it breaks off and hunks could end up in the motor. Use something tougher, like JB Weld maybe.
 

conquesttsi

Well-known member
Joined
Feb 4, 2009
Messages
209
Location
Northern Connecticut
Thanks everyone for your input.
All 3 of the mas in question (609,399,489) are all 240 liter sensors. That's 509 CFM for you non engineering minded types. The difference between the three is how much psi drop you get across the sensor, which is what I think Jeff was getting at. Lets take the psi drop out of the equation for just a second. If a 240 liter mas (509 cfm) Is on a turbo that will max at 550 cfm isn't it safe to say the mas is underated for the turbo?
Not trying to argue just very intersted. I love talking about this kind of stuff.
 

IM running a 501, I merely put a screwdriver between the base and the horn and it popped right off. Im running 560's and have to ADD 30% across to get my fuel trims in check. I would say 750's would mate perfect to an unhorned 501.
 

Quote:
Im running 560's and have to ADD 30% across to get my fuel trims in check.



This isn't an ideal way to do it. Installing a 3G MAS with 560's without the proper MAS compensation adds 2-4* extra timing advance, which really limits how much boost you can run. Also, the 1G stock maps stop at
 

conquesttsi

Well-known member
Joined
Feb 4, 2009
Messages
209
Location
Northern Connecticut
Wow. That is something I had never considered. Looks like she will be all set. Shes got 650's and a chip with AFC to fine tune. I've got link and 880'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