The Authoritative 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 account, you won't be able to reset your password. In that case, follow the instructions here to regain access to the forum.

Free mods


Staff member
Feb 21, 2001
Franklin, TN, USA
Air Silencer
[*]Located behind the Mass Air Flow sensor, there is a paper silencer.
This does help silence the sound of the BOV and turbo some but hurts power.
Take this out.
Remove Air Can
[*]Remove the air box completely.
Under hood temps are higher but the turbo can suck more air in with the air can removed.

Block EGR
[*]The EGR re-circulates exhaust gas back into the intake manifold.
This is done to help fuel economy and emissions.
When you block the EGR with a plate (which can be made from any piece of scrap metal), the intake manifold will not get as hot at idle/cruising.
This helps keep the air intake charge cooler which makes more power.
[*]Another beneift is that it keeps the throttle body clean because you won't be re-circulating exhaust gas back into the intake manifold.

Bypass coolant lines
[*]Mitsubishi designed the throttle body to have 2 coolant lines run to it in order to have a smooth idle.
During the summer, this feature really isn't needed.
The problem with running coolant lines to the throttle body is that it heats up the throttle body with engine coolant.
Bypassing these lines and basically have the lines loop around the throttle body will help keep the intake charge cooler and thus making more power.
[*]During the winter, this mod makes the idle surge until the car is warmed up.
I suggest doing this mod before trips to the track or during the summer.

Crush the BOV
[*]The BOV (Blow Off Valve) releases pressure out of the upper intercooler pipe when the throttle plate closes when you shift. This helps keep the turbo spooled. A problem with the stock BOV is that it releases air out of the valve too early. The only time you want to release air is when you are shifting.
[*]The fix is to crush the BOV. Place the BOV in a vise and crush it until the nipple on the top starts to touch the outside edge of the BOV. You still have to vent the BOV back into the air intake hose unless you buy a VPC.

Recent Classifieds Listings