TBI to MPI update + E-85

[Rampage1967]

As all of you probably remember I converted a 1987 Caravelle 2.2 auto to MPI using a 1 piece intake & turbo injectors.

Since the conversion I have settled on using 24 pph 3.3 V-6 injectors since both of my sets of turbo injectors had 1 bad injector a piece.
All are low impedence. Fuel pressure is set to 38 psi on E-85.

Other than the factory programmed idle glitch, the engine runs great, very smooth. Gas mileage is same as on TBI & gas. Performance is much improved, pulling hard through the midrange & decent to the rev limiter.
Cold starting is a two try deal on E-85, but once running drivability is fine.

Now for a question:
Has anyone ever tried to run a 2.2 TBI on a 2.5 TBI computer?
I want to convert my Logic Module system to a SMEC system to fix the idle problem the car had even with the stock system & 2.5 engines are more common than 2.2s around here.
Can anybody tell me the timing & fueling curve differences between the two??

[shadow9]

I was running a 2.5 of a 2.2 computer, the opposite of what you want to do but works the same both ways, i didnt notice any diffrence at all and it ran fine, the only reason i went to a 2.5 computer is cause my 2.2 computer got wet and fried and all i could find to replace it was 2.5 computers.

[sgtarky]

rampage, did you get my private message, getting close to getting mine done. fugging money ran dry again. looks like july now before it'll run. just got to buy the gaskets oilpump and torque converter

[Endo]

i'm interested in running E-85 in one of my cars, whats involved in that?

[Rampage1967]

All I did i turn up the fuel pressure untill it showed the proper full power mixture & tweaked the timing. It is a little hard to start cold, but runs grat once running. I'm told it cleans out the fuel system & plugs fuel filters in older vehicles with dirty fuel systems, but, I haven't had a problem yet.

BTW. the pressure went from running rich at 35 on gas to just right at 38 on E-85.

[lebaron dude]

I have an 87 Lebaron TBI

When my first engine was rebuilt the jerks that rebuilt it put in a 2.2L engine and never told me (this was 10 years ago when I didn't know anything about cars). The LM and PM are original equipment (2.5)

So the 2.2L engine has been running on 2.5 electronics and mostly what I've noticed is:

1) O2 sensors seem to go every 12K miles (makes sense, the computer will run rich by default (before feedback and at WOT) and running that way seems to make the sensor fail faster)

2) Performance is horrible.

3) Takes longer to warm up (always running rich before going into closed loop means cylinder temps are down)

[DaytonaTurbo87]

dude, just so you know, the 02 sensor can't modify the fueling enough to make up for the extra fuel the 2.5 computer is giving it. The 2.5's fuel curve is programmed roughly 17% richer throughought the whole curve. The 02 sensor can not adjust the fuel ouput by nearly that much. 02 is good just for a few percent to help get best mileage/driveability during normal driving, it's not able to take out 17% extra fuel flow, so even when you are in closed loop and the 02 is working, you're still running way rich. If you get an adjustable fuel pressure regulator, you're fine as you can just turn down the fuel pressure and run the 2.5 computer on a 2.2 fine, but with the stock regulator, I wouldn't run it for too long.

And about your E85 swap, did you add in the stainless fuel lines or plastic gas tank from a ffv car?

[Rampage1967]

actually, if I use a 2.5 computer. I'll turn down the fuel pressure to a lower setting. I already have an adjustable regulator.

As far as the gas tank goes . . . I used the stock tank & lines, just like others have done.

[sgtarky]

Hey, Rampage, I finally got an email from the guy that converted that daytona. He still lives in my area and said he would help me out with the conversion. anyway, he says he went and converted it to turbo.

[DaytonaTurbo87]

Quote:

Originally Posted by Rampage1967 actually, if I use a 2.5 computer. I'll turn down the fuel pressure to a lower setting. I already have an adjustable regulator.

true, you are fine with an adjustable reg.

[Rampage1967]

I may end up converting mine to turbo electronics due to that nasty stalling problem it had stock too.

That guy with the daytona did say on his page that he want's to turbo it.

[sgtarky]

rampage. he did turbo it, I think I will pay him a visit get some parts from him.

[Rampage1967]

I think I may have roasted a power module on mine, but, then it's had something wrong since before i converted it. I think i may just go the turbo electronics rout since i have a some of the parts.

Otherwise it's try another power module & see what happens.

The car was running so good too.

[phantomrt]

Actually, the adaptive fuel trim will go to about 24 percent. Closed loop operation shouldn't have been a problem, but anytime under open loop, well, thats a problem.

The stuff from the 90's can go 24 percent, but maybe the 80's programming isn't so advanced.

[Rampage1967]

I noticed there's a hell of a lot of leway at part throttle.
Tune it right wide open & it tune's itself for part throttle fairly well.