Difference 85MP T1 and 85 T1 stock

[amcpacer]

Hi,

I am buying a MP T1 computer from a guy and I am wondering if it will need larger injectors than the OEM 85 T1 injectors I am using currently. Also what are the differences between the two computers?

When I get the computer I may remove its EPROM and download its data with my EEPROM burner to upload to the forum.

I just want to find a way to run higher boost without a cutout kicking in. I will not even consider a map bleed or zener diode either. I have a water injection system that is soon to go in, and when time permits I will put in my spearco style log manifold and FMIC. I am hopeful the 85MP T1 computer will let me raise the boost to around 14psi.

[Turbodave]

The MP computers all are designed to work with the stock injectors (except the S-60 computer). The 85 will up the boost from the stock 9-10psi to around 11-12 psi and it's got a more aggressive spark curve from what I remember. Putting one in my Shelby Charger was a noticeable improvement from stock. I'm pretty sure they still have overboost cutout enabled, so it may not let you run the 14psi your looking for depending upon how picky it is. I've seen some cars cut out at 12-13psi, and others run 15psi all day, so different combos of computers and Map sensors yield different results.

[NeonShowCar]

I used to run a MP T1 computer in my 86' SC back in 1989 (yes that long ago). I had installed the 803 injectors as I too raised the boost to 14psi. Though I never hit cutout because I had soldered in a ziener diode across the MAP. If you really want 14psi w/o cutout, you might want to consider that Ziener Diode trick.

[amcpacer]

That is great that I can keep the stock injectors. I will just be sure to run 92 octane all of the time then since it has more agressive timing. Hopefully the MP module will not run rich and hurt fuel economy. I think the S60 was the one that leads to poor economy and does not use the O2 sensor.

Maybe there will be some way to use Chem to disable cutout for the 85MP and then put an EEPROM with the updated cal back in. Ill bet nobody has ever disassembled an early T1 cal before. That may be a huge obstacle.

[Spraynlog]

I have run the '86 MP logic module for several years in my Lebaron. You should be aware that it will not pass an emmissions test, so keep the stock one handy to swap back in if you live in an area that tests the tailpipe.

Other than that, I like the way it runs...seems smoother than the stock computer in everyday driving. In back to back testing, it also seems worth about .3 of a second in the 1/4. The mileage I got was no different than stock. If you are running higher than stock boost, I'd use 92 octane all the time.

[amcpacer]

Wow 0.3 sec is not that much faster. I remember when I took the 86GLHS cal out of my daytona and went to a custom 87blueberry cal the difference was amazing. Probably more than a second faster.

If it makes the car smoother though that will be great. I am not okay with increasing the emissions of the engine though (even though there is no testing here). Did it increase CO, HC, or NOx emissions? Perhaps an adjustable FPR and slightly lower than normal pressure will get the emissions back in check.

[cordes]

Wow 0.3 sec is not that much faster. I remember when I took the 86GLHS cal out of my daytona and went to a custom 87blueberry cal the difference was amazing. Probably more than a second faster.

If it makes the car smoother though that will be great. I am not okay with increasing the emissions of the engine though (even though there is no testing here). Did it increase CO, HC, or NOx emissions? Perhaps an adjustable FPR and slightly lower than normal pressure will get the emissions back in check.

From what I have seen and read about the MP cals it will run richer at idle. I think it was one of the guys on chem who looked at the o2 clicks on the MP vs. regular cal, and the MP was set up higher so that it would always run a little richer even at idle.

There is very little support for the early LM cals, but I believe there are a couple of guys who work with them.

[amcpacer]

I must locate the guys that work with the early cals. I think a post must be in order soon over at the chem website.

[BIGBRUDDA]

Contact MW6886 here on turbo mopar. He does custom cals. He did some for me, was worth .5 sec outa the box. Tell him I sent ya, and you want the "special shipping" option.

[amcpacer]

Okay today I got the 85MP Logic Module installed. Upon startup I noticed the engine had a much smoother idle. It is amazingly smooth so I can barely feel any vibration at idle. The boost seems to come on in a more noticable fashion. It does not feel very much faster though it does seem more responsive. It accelerates sooner than the stock cal which sometimes leads to a slight delay when I go to WOT. I never heard any pinging at all during many high speed runs around local highways. Overall I am very pleased with the MP computer. Now I must install my water injection system or get some sort of intercooler installed. One of the two is imperative!