Hey everyone, wanted to make a post to get a game plan for my Blazer. My transmission died on me Friday so I'm looking at options for doing a V8 swap, something I've been dying to do for awhile now with this style chassis. I figure if I'm pulling the engine and transmission to replace the transmission I might as well go for it. I found a 5.7L Vortec with a 4L60E from a 1998 C1500 at the local junkyard for about $600 for both. My 2000 Blazer is a Vortec as well and I've been reading that the swap itself is extremely worth it. Here's the part list of what I have so far:

S10V8 motor mounts/headers
98+ Intrepid Fan with fan controller
Recessed radiator and aftermarket condenser
Custom exhaust setup

So my main question is the wiring. I've never been much of a wiring guru so I'm a little lost. I've read that my 2000 PCM can be flashed with the stock 5.7L tune. My question is will I need to repin the actual PCM itself for the new engine? I've read that you don't need to unless you're using a V8 PCM from your donor vehicle. I've been told that you have to jump the pink wire over from the V6 injector harness to the extra 2 cylinders' injectors, but there's another one for pulsating the injectors that I'm not sure where I would get the signal from. Also, with using the same computer does PATS/VATS become a problem with the swap?

Thanks for any advice you guys might have!

 

Call these guys. I'm sure they can help answer all your questions about wiring and program your computer (or supply you with an exchange). Should be a VERY nice swap and absolutely everything should work. Make sure you don't mount the engine in the "high" position. Grind the tabs off the mounts and use the other bolt holes to keep the engine down where it should be (measure factory engine height before you remove). Driveshaft angle depends on it. This should allow the headers/trans to fit too, and not hit the firewall/trans tunnel. Get an aftermarket oil pan if it doesn't clear the crossmember. I like the Milodon S10 swap pans and oil pickups. Must be a 2WD Blazer if you are planning to use a trans out of a C1500. You may be able to use the factory fan and clutch and at least parts of the radiator shroud if you are moving the radiator forward into the support. Check out Superior Radiator for a bolt in S10 swap radiator. I think is probably as good as the little 1985 Corvette radiator many use (I have used both). Neither one will cool my 383 - factory fan, aftermarket electric fans, 2-speed Taurus fan, electric water pump, doesn't matter - but it has a big cam and inefficient combustion at low speeds. Your experience will vary.

If I remember correctly there is probably a way for the PCM to control electric fan relays, eliminating the need for a fan controller. You can discuss with those who program the PCMs.

https://harristuning.com/obd2/vortec-4-3l-to-5-7l-swap/

 

Thanks, I'll give him a shout and see if I can get some guidance!