2000 7.4l MPFI swap into 1995 7.4l TBI

[Dinkster]

Hi, i'm new here and hope someone can help me out with this. I posted this on another site but didn't get any replies. I daily a 95 K2500 with the TBI 7.4l 4L80E and I have a 2000 K2500 parts truck with the MPFI 7.4l and I am looking to swap the FI to the 95. I am wondering if the VATS on the 2000 is built into the ECU or is it self contained. If so then could I wire up the ECU from the 2000 without the VATS since it gave me nothing but issues when it was being driven. And on that same note, does anyone know of or have a wiring diagram that would give me the wiring necessary to hook up the ECU?

 

[ZRoe]

Just a thought from the peanut gallery, but you may need to get your black box tuned/modified to remove VATS or you could just give in whole hog and do a 0411pcm swap during the engine swap which will also require tuning and VATS delete but will offer improves performance.
If it were me I'd even swap the cam while the motor is out and accessible.

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[454cid]

...I have a 2000 K2500 parts truck with the MPFI 7.4l and I am looking to swap the FI to the 95.

Any reason you can't swap the whole engine?

 

[Dinkster]

I plan on swapping the entire engine after a refresh (plus cam) but the issue I'm having is that the 00 has VATS and the 95 does not. I need to eliminate the VATS. Plus determine the pin locations/ wire colors if I need to tie it into any of the interior accessories.

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[Dinkster]

I guess I'll probably end up doing the 0411 swap I was just hoping I wouldnt have to do it at the same time. I was wanting to do the FI swap first, get it running, then do the 0411 swap but where's the fun in that?!

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[woody80z28]

You could run the port fuel injection with the TBI computer setup. I'm working on that now. It requires a little soldering and burning a new tune for the OBD1 computer, but it may be the least work.

 

[Supercharged111]

You could run the port fuel injection with the TBI computer setup. I'm working on that now. It requires a little soldering and burning a new tune for the OBD1 computer, but it may be the least work.

Biggest challenge with that is finding a competent tuner. Otherwise I agree.

 

[Dinkster]

That's a good idea! Thanks. So, then I have a few other questions about that. Can the injector drivers from the TBI CPU handle 8 injectors? I'm assuming then the whole setup will be batch fire with all injectors firing at the same time, correct? Was the factory MPFI on the 2000 that way or was it sequential? Lastly, what's involved with the conversion?

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[Supercharged111]

2000 was sequential, not sure if the modded TBI PCM is or not but who gives a crap.

 

[woody80z28]

Here's a link with info. You have to remove two resistors on the ECM and replace them with wire in order for the two TBI injector drivers to run the eight MPFI injectors. There's also one jumper on the PROM itself. The Gearhead site is full of great information on OBD1 stuff.
http://www.gearhead-efi.com/Fuel-In...PCM-Information-0D&p=2855&viewfull=1#post2855

It puts the truck in batch fire (4+4) and not sequential, but I prefer the OBD1 computers because they are so cheap to work on and modify. You could do the tune yourself with hardware from Moates and the stock O2. That will get you 90% there, and the other 10% you can do with a wideband.
http://www.moates.net/gm-19851995-c-64.html