My 84 hot air swap build

J

jmcgrath22

New Member
Joined
May 27, 2013
Well to start this off I will first tell you a little about my swap and what I am after as far as knowledge from all of you. I purchased a mostly complete 84-85 turbo 3.8 awhile back for an engine swap on my 93 Toyota pickup. When I say mostly complete I mean everything besides wiring. I have the motor installed in the truck now, exhaust is done, radiator and fans are on the way. My question to you all is what is the easiest way to wire these motors from scratch... I've seen the full wiring harness found on summit here: http://m.summitracing.com/parts/rfw-tb86?seid=srese1&gclid=COzOnpDKq7wCFWVxQgodoEcAYA. However the price is fairly high and the last thing want to do is pay extra for random censors and circuits that will not be used in this swap as it is pretty bare bones (electrical wise) since everything else on the truck is factory Toyota. To put it simpler I would just like input for a list of parts needed. I've read that the 86-87 model ecu and chip is needed for this wiring harness but I would like someone to clarify all that is need to take a motor with pretty much no wiring and make it run with no extra unneeded sensors or smog
 
image.jpg
 
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This is a photo to show the project it self if anyone is curious. Thanks in advance for any input
 
That's a cool build! I believe caspers has a complete wiring harness for like $200. Idk if thats your best bet.
 
Wahoo said:
That's a cool build! I believe caspers has a complete wiring harness for like $200. Idk if thats your best bet.
Click to expand...

Hmm I've looked in their site and the only compete kit I found was more expensive then this.. Do I really need allllll of that to run my motor as is? I really just wana the bare minimum to run this motor without any extra bull
 
jmcgrath22 said:
Hmm I've looked in their site and the only compete kit I found was more expensive then this.. Do I really need allllll of that to run my motor as is? I really just wana the bare minimum to run this motor without any extra bull
Click to expand...
With all the HA conversions, you can get a good used harness for about $150. Caspers is about $850.

Used harness is easy to locate and plentifull.
 
Jerryl said:
With all the HA conversions, you can get a good used harness for about $150. Caspers is about $850.

Used harness is easy to locate and plentifull.
Click to expand...

Where is the best easiest place to buy one and what spread of models and years will work forum application
 
jmcgrath22 said:
Where is the best easiest place to buy one and what spread of models and years will work forum application
Click to expand...
Post in the wtb section, or contact gbodyparts, intercooled88 etc. You are looking for 84-85.
 
jmcgrath22 said:
Well I would love to be that new owner. Is it complete or missing a few components
Click to expand...
Remind me at the end of the week and I'll take some pics for you. I caught a bug this weekend and don't get home until 6PM. The bug is taking it's toll but I'm supposed to off Saturday and I can take pics then.
 
I will post here instead of in the conversation.

In addition to the engine harness/ecm you will also need the ESC module off the passenger fender (I should have one) and there is a separate dash harness that connects near the ecm in the cab. Most of the essential wiring is contained in the engine harness but not all, you may want to start with a dash harness or at least get a harness pinout to know what needs addressed. The fuse box is part of the dash harness.

So if you've never held an engine harness, I will try to spell this out for you. it connects to the drivers side bulkhead connector under the brake booster and the back side of the fuse panel is the opposing connector for the bulkhead (part of the dash harness). It hits all the essential stuff in the engine and wraps back around and goes under the ac box and the ecm is in the passenger kick panel in the interior. That's why I said the passenger fender has to come off, just to get the last 6-8 inches of wire with the ecm connectors on it AND it connects back to the dash harness on the passenger side near the ecm with 2 connectors.

I think I have an 84 NA dash harness already out, and I've been told the only difference is the wires for the factory boost gauge and tach in the cluster. I don't know that for sure but it'd be an easy (and cheap) way to gut a harness for the essentials. Obviously the ignition switch power comes from the dash harness as well as the volt light wiring to make the alt charge and the factory idiot light wiring for the oil and water temp. Crap I just remembered the vehicle speed sensor is on the back of the factory cluster and you will have to deal with that too if needed. What trans/converter are you running?

Side note: These cars do have a MAP sensor but it is ONLY for the factory boost gauge and you can leave that unhooked.
 
INEEDAGN said:
I will post here instead of in the conversation.

In addition to the engine harness/ecm you will also need the ESC module off the passenger fender (I should have one) and there is a separate dash harness that connects near the ecm in the cab. Most of the essential wiring is contained in the engine harness but not all, you may want to start with a dash harness or at least get a harness pinout to know what needs addressed. The fuse box is part of the dash harness.

So if you've never held an engine harness, I will try to spell this out for you. it connects to the drivers side bulkhead connector under the brake booster and the back side of the fuse panel is the opposing connector for the bulkhead (part of the dash harness). It hits all the essential stuff in the engine and wraps back around and goes under the ac box and the ecm is in the passenger kick panel in the interior. That's why I said the passenger fender has to come off, just to get the last 6-8 inches of wire with the ecm connectors on it AND it connects back to the dash harness on the passenger side near the ecm with 2 connectors.

I think I have an 84 NA dash harness already out, and I've been told the only difference is the wires for the factory boost gauge and tach in the cluster. I don't know that for sure but it'd be an easy (and cheap) way to gut a harness for the essentials. Obviously the ignition switch power comes from the dash harness as well as the volt light wiring to make the alt charge and the factory idiot light wiring for the oil and water temp. Crap I just remembered the vehicle speed sensor is on the back of the factory cluster and you will have to deal with that too if needed. What trans/converter are you running?

Side note: These cars do have a MAP sensor but it is ONLY for the factory boost gauge and you can leave that unhooked.
Click to expand...


Wow thank you for the great info. Sounds like there is a lot more to this then I thought. I'm sure there will be many wires I don't need but I want to do it as clean as possible so I'd rather have it all to start with then waste another month trying to piece it together. Is this something you would (when you had the time) be able to pull off an ship ? Thank you

John
 
Yeah I should be able to set you up with all that. Dash harness is a definite maybe lol. Almost all important stuff is contained in the engine harness and there won't be much if any to remove except the bulkhead connector side. Start getting familiar with the wiring diagrams on gnttype.org :)

What trans/converter are you running?

Sent from my LGL75C using TurboBuick Mobile mobile app
 
INEEDAGN said:
Yeah I should be able to set you up with all that. Dash harness is a definite maybe lol. Almost all important stuff is contained in the engine harness and there won't be much if any to remove except the bulkhead connector side. Start getting familiar with the wiring diagrams on gnttype.org :)

What trans/converter are you running?

Sent from my LGL75C using TurboBuick Mobile mobile app
Click to expand...


I plan on running my 4l60e and np208 tcase. Going to experiment with different programmers and facory gm controllers for the trains or just install a manual shift kit
 
I assumee you got a bolt on bell 4l60e and a bop housing?

Only reason I asked is because I don't think you'll need the oe speed sensor if you don't need the ecm to control lockup. The oe trans has a third and fourth gear pressure switch that tells the ecm the upper 2 gears and is used for timing control. Without them it will just stay in the low gear tables and is probably not a big deal. If you get a custom chip down the road (recommended) the chip guy might want to know that.
I've never tried to run without the speed sensor but I don't think it'll be a big deal (might set a code but any chip guy can eliminate it).

Sent from my LGL75C using TurboBuick Mobile mobile app
 
INEEDAGN said:
I assumee you got a bolt on bell 4l60e and a bop housing?

Only reason I asked is because I don't think you'll need the oe speed sensor if you don't need the ecm to control lockup. The oe trans has a third and fourth gear pressure switch that tells the ecm the upper 2 gears and is used for timing control. Without them it will just stay in the low gear tables and is probably not a big deal. If you get a custom chip down the road (recommended) the chip guy might want to know that.
I've never tried to run without the speed sensor but I don't think it'll be a big deal (might set a code but any chip guy can eliminate it).

Sent from my LGL75C using TurboBuick Mobile mobile app
Click to expand...


It's a normal gm pattern 4l60e with an advanced adapters gm-bop adapter plate. I would like to eventually buy a programmer for the tranny but spending 600+ on a programmer when I would like to go back To manual trans someday, just doesn't seem cost effective. So with transgos shift kit it will be full manual shift which will kinda suck at times no being able to put it in drive and go. I will most likely find a low miles th400 and run that till I work out all the bugs. Taking the "E" out of 4L60E just seems pointless but when the tranny and tcase are free it's worth making work
 
Now when you say chip are you referring to the "prom" I always read about and if so where is that located? Part of the hole ecu, relay, fuse block assembly
 
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