MPS Adjustment, It helps to have the right tools Options

[Mblizzard]

I post this only because I struggled to find the proper tools to adjust my MPS after going to a 2056. While I was able to make adjustments using standard tools, I could never get it exactly right. I asked several people about where I could get the right tools and could not find them. It is likely that this is well known to everyone but me, but I finally found what I needed at Tangerine Racing.

It is such a simple tool but without it you can't really be sure you are adjusting only one of the screws without changing the other one. So once again Chris is the man that can put the right tool in your hand. I have been close on the adjustment many times only to mess it up trying one more small change.

If you are playing with your MPS just get one of the MPS tuning kits from Chris it will make your life much easier.

[Steve_R]

Can someone outline the steps to adjust the MPS using a dyno and an exhaust gas analyzer?

In my area there are several shops that have a dyno and can measure AFR (air-fuel-ratio).

Can I just record the AFR under full load, turn the engine off and make an adjustment.
Then, repeat until the full load AFR is at the correct value?

[Bleyseng]

Can someone outline the steps to adjust the MPS using a dyno and an exhaust gas analyzer?

In my area there are several shops that have a dyno and can measure AFR (air-fuel-ratio).

Can I just record the AFR under full load, turn the engine off and make an adjustment.
Then, repeat until the full load AFR is at the correct value?

First remove the WOT stop without destroying it by heating the epoxy and turning it in so you can dig the epoxy out of the threads. Then back it out.
Now you can go on a dyno and run under load in 4th gear at 2500 or 3000rpms and check the AFR. 13.7 to one great onto the next test.
Run it thru the gears to 70 mph in 4th under load. What is the AFR on the dyne chart say? Should be pretty flat around 13.5 to 13.7 to one.

Now do the WOT test in 4th gear and it should start out at 2000 rpms at 11.5 to one and then climb to 12.5 to one at 5000 rpms. See your printout. If it's good install the WOT so it barely touches using a Wavetek to tell you when it hitting. If it's too rich install it and adjust to that spec using multiple dyno runs to do it.

Finished? Test drive it and it should be really smooth accelerating and have plenty of power until 5000rpms under WOT.
Now, epoxy the WOT stop so it doesn't move and make sure the vent holes on the MPS are facing down so water doesn't get into the diaphragm area. Too many MPS's are mounted wrong so water gets in and rusts em out.