V8 in 89 4x4 Blazer

[cleaneststock89]

I have a 89 S10 blazer 4x4 4.3 tbi I want to put a 305 or 350 in and keep the ac and c/c. basicly look stock I need to know if i use a motor out of a full size pickup around the same year with the same tbi can i use the same wiring and/or do i have to change the ecu? I'm going to use one of those kit that come with the motor mounts headers ect........ Can i use the stock trans the truck only has 75000 on it.If i can not use the tbi can i put a carb on and call it a day. My truck also has a dig/dash i think the tach my not work right is that tru. Any help for a newbie. Been working on these trucks for years but never did a v8 in one.

[85s10tpi]

get the 305-350 computer out of the donor vehicle and plug it in to the stock harness. along as your not pushing 350+ horse the 4.3 trans will work fine. use all the stock a.c./cooling setup.

your digi dash will have to come apart to be modded. I'm not sure how to do this. the digi dashes are very problemsome,and I'm not even 100% sure they can be changed to read a v8 properly.

manifolds or 4x4 swap shorties are your only bet for exhaust. unless you want to fork out 500 for hooker long tubes.

[cleaneststock89]

Thank for the info now what year full size will the doaner truck have to be so that the wiring is the same?And sorry to be a pain about the dig/dash but will it still work when i change ecu's My odometer is digital,Thanks for all you'r help guy. Happy holidays

[Rickracer]

I cant say for sure whether the digital dash will work with a new ECM or not, (I'm thinkin probably not), but they are well known for problems, I'd swap it out anyway.

[cleaneststock89]

I realy would like to keep the dash the way it is that is the one thing i love about my truck+the dash is only 2 months old brand new from GM.So any help with that.thanks

[85s10tpi]

if your blazer has a tbi injected 4.3 then the swap is as easy as you can get. if you have a CPI 4.3 then some of the harness will need to be modified to accept the tbi setup.

donor veicles are VERY pletiful. any 87-95 v8 pickup, blazer, suburban, vans, etc. and any 87-93 caprice,roadmaster,fleetwood.

[92tpi]

you can get one from a rs camaro caprice buick or a c/k series truck or van 87-95 engines will work but you need a ecm from 87-92 cause 92-95 tbi's have 4l60e's and won't work with your 700r4,and don't get a f-body ecm because they have vats in them.

[cleaneststock89]

Thanks guys.I think my truck is a tbi it looks like a carb w/two injekters over top,one over each hole.Still can use a little info on dig/dash if it's out there.

[92tpi]

just take all the sending units off the 4.3 they will all fit on a 350,there not wired into the ecm,just like dakota digital gauges you just need the sending units.

[91slammins15]

Digital dash will work fine with your swap the only thing that won't be right is the tach. There is a fix to make the tach work properly but the digital tachs are crap and only read in 500 rpm increments after 1500 rpms anyway so just get a different tach. Mine has been working perfect for 5 years since my TBI 350 swap.