OK my 1rst real question...

[sgt. minivan]

ECM...

OK i know on my 1987 voyager that the rev limiter is set at 5800 rpms, ave also heard that there is no way of upgrading these ecm's nor can they supply more fuel if more air is detected, so without using a stand alone or megasquirt, can i just simply swap in another ecm from something else and turn the key? i know in shadows that the manual ecm allows more rpms to rev limiter., i heard a guy claiming 6800 rpms from a stock ecm... is this posible, i dont know what vehicle, i just know it was auto, 3.0l, also i wanted to add my voyager is not turbo yet, im not looking for a turbo ecm., also ive had my van up to 115-125 mph (no joke) im assuming it has no speed limiter.?? so to sum all of this up in questions...acually i add one more... what makes my speedo needle flail back n forth (withen a 10mph range) at speeds above 90mph? cable?

1. what ecm can i plug and play for better performance
2. im right about the 1987 ecm cant be adjusted?
3. does my 1987 voyager have a speed limiter?
4. why does the speedo needle flail?

THANKS!!

[Ondonti]

6200 is the 5 speed transmission ecu rev limiter

[sgt. minivan]

will it plug and play???? what vehicles can i get one from if it is a plug and play? thanks Ondonti!

[Phatfoto]

As for fuel... Hmm, how much do you need? Back when I had my van, an 87, I put in Turbo 1 injectors. Remember the 87s were the first year of the 3.0. The 87s have a lower fuel pressure than the 88s, it was upped for 88 because fuel was boiling in the fuel rails. Anyway. When I first added the injectors, I also swapped in the turbo FPR. BIG mistake. The motor didn't want to idle, and it ran very rich, darned near flooding. I swapped back to the stock 87 FPR and it smoothed out. The ECM adapted and it ran great. I also had a the intake plenum hogged out, the lower manifiold runners had been smoothed, and I was using the manifolds from a 89 for the 2.5" outlet (and smoothed them on the inside as best I could...). I also did one other thing that I haven't seen anyone else do. And my butt dyno and fuel mileage told me it made a difference. I swapped in a later model rocker arm set so I could use the roller arms on the 87 cams. And I ran a couple different open element filters over the years too, in the desert, no fan on the ECM. And at the time, I lived in the California Mojave desert. Never burned up an ECM.

So the ECM can compensate some for fuel. I never made it to the point of adding a turbo to see if there was enough fuel to compensate. Chances are, with the 87 ECM, adding a turbo, larger injectors and adding more fuel pressure will work up to about 7 or 8 psi. After that, all bets are off.

In 87 only the minivans had 3.0s. I know ROb Carter swapped car ECMs into his 88 van with some success. Do not know if the harness changed between 87 and 88...

I had my van to 115 and ran into the aero wall. I just needed more HP... Speed limiter for the 87s? Don't think so as far as I know. My 94 Concorde was limited at 105, my F150 Supercrew is limited to 100, my 03 Neon cuts out at about 122 indicated. 87 van? No idea.

[ShelbyDodgeImp]

When swapping around fuel and computer stuff remember the impedance of the injectors changes in 91. The newer systems will NOT use the old 80s turbo injectors and the older systems won't use the newer injectors.

The advantage to the higher impedance (newer) systems is you can use any number of the GM or Ford aftermarket products out there (like the 5.0 stuff). I dunno how prices vary or what is (or is not) available for the low impedance systems but you can find virtually any size injector for the commonly moded engines like the 5.0

If keeping the stock rev limitor I would play around with fuel rail psi, adjustable fuel regulators, raising regulators and different injectors before swapping around computers but that's just me.

[sgt. minivan]

nice!!! great info guys! yeah i learned the hard way that injectors had a different impedance, when i did my engine swap (94 3.0l) i had recently bought new injectors for the 87 3.0l (before i blew it) and was like 0HH!! il use these injectors i just bought and put them in the 94 engine..... needless to say IM so glad i swapped injectors back to the 94's..... that was the only time ive ever trouble shooted anything and fixed it on the first try... could been there for weeks on that issue. (i didnt know impedance changed at that time) so anyway your saying that the "new" system can run almost any injector? if so than that saves alot of frustration + helps out my turbo plans, and il ask again, does anyone know if i can (for ex) go to a junk yard, yank an ecm from say a 3.0l 5speed datona, and put it in my van with no issues? will it even plug in?

and what i was getting from your statement phatfoto, that the 87's cams are larger? will 87' cams fit in a 94 head with no issues? (if they are infact larger) but if i were to go that route.. id just put a beefy aftermarkett cams in.

[ShelbyDodgeImp]

No I am saying they can use any high impedance injector which would be MOST of whats on the market since thats what the Phord 5.0 guys and alot of the GM models use.

It is NOT backwards compatible with the low impedance injectors.

[Phatfoto]

Before 91, use the low impedance. And it doesn't matter what year the motor is, it matters what year your ECM is. As for what ECM swaps? You would need a 87/88 and other year service manuals to make sure ECM pinouts are the same for vehicle to vehicle swaps.

As for the cams, I don't know if the 87 and the 94 are interchangable, but I swapped the roller rocker arms from a 92 motor into my 87 motor. I can't imagine they were that much different size wise. The cam profile is a little more aggressive. And I felt a real difference in that swap, as well as a 2 MPG increase in economy.


Personally, I would slow down a little. Read some more. A few people helped me put together a neat bunch of 3 liter info. geocities.com/phatfoto and look under the repair info. Lays out Mitsu and Hyudai cam profiles and lots of other info too.