Tbi / 700r4

[truckster]

Yesterday my Blazer threw a rod on the way home. It looks like the block may have sustained some damage, so I'm not considering rebuilding it.

I looked at crate motors, and they're just too expensive for what I want.

So I have an opportunity to buy an 89 with a 5.7 and 700R4. If any of you are running that combo, especially on a 4wd, I'd love to hear what your mileage is and how the install went.

I know I'll need a trans adapter, and I plan on moving the engine forward to leave the driveshafts alone. How much of a pain was hooking up the ECU? Anything else I should know about?

Thanks, I know you guys always have a lot of information to share.

[steelhorse]

You will probably be better of posting this in the 4x4 section. Someone was talking about this the other day.

[MARKDTN]

ECU is easy to do. Vans have the easiest harness, but trucks are not that bad. You may be better off with buying the transfer case from the donor and leaving the engine mounts alone, but I don't know about that part. Adjusting driveshaft lengths may not be as bad as all the adapters and moving the engine.

[truckster]

I would be getting a complete donor vehicle, so I can use whatever parts I need to. It's an 89 Blazer. I know there are some guys who have done this in 67-72 trucks, and I'd like an idea of what I can expect.

Thanks again.

[MARKDTN]

OK, '89 Blazer is like a 73-87 pickup. That one has a good harness that is fairly self-contained. The ECM is above the glovebox and the wiring has a nice plug through the firewall. With a good wiring diagram you should be able to find the hots and grounds and figure out the fuel pump wire. Not sure about the fuel tank, but it may work too. You can mount the ECM in about the same location. It will be easier to find a good place for it without A/C.

[truckster]

Thanks for the help. I'm hoping the fuel tank will fit, so I can use the internal fuel pump. I plan on using everything I can from the donor, except maybe the transfer case.