84 to 87

#1
Gentleman, I could really use some help. Has any of you folks took a 84 car and converted the motor to an 87. I am looking at one that has most of the engine in but needs to be finished from the engine forward and the wiring finished. Has a new 87 wiring harness but still needs some of the wiring finished plus needs the engine finished from the water pump forward. the person has sent pics of all the parts to finish. Just needs installing. when done how many had problems. Did the car run ok. What problems did you encounter. Any help would be greatly appreciated.
 

NorCalTurbos

Slowing down to SPEED UP!!!
#3
Get a complete motor,trans & wiring also you’ll need the ecm. Otherwise you will be piecing it together spending just as much if not more.
 
#6
Several of us have done what you wish to attempt to pull off; you are biting a big bite though if you are not adept at electrical efforts. I admit this is an area where I suffer... and the rarest '84 GN in the Nation is sliced up by me. ~smile Don't call it a Hot Rod if you are unwilling to cut it up.

The power steering unit... you will go manual S-10 and a White Racing alternator relocation bracket is what you are looking for to clean up the mess mechanically.

You will have to go to a Casper's Electronics Wiring harness.... don't waste your time attempting to overcome the necessary '87 sensor locations on the Hot-air harness.

Exhaust is a plus... you now gain more options. Be aware if you go aluminum heads GN1 you will probably have to modify your crossover tube.

Fuel system mods... You will require some modifications here.

That covers most of it... it isn't for the feint of heart.
 
#8
That... is uncalled for... period.
My bad. Didn’t mean to offend anyone. I did the cold air conversation in my younger days and it cost me more then the car was worth. My point was just keep it as a genuine 85 GN because it’s worth more being a genuine 85 GN. And if u want an 87 then buy an 87. And if u can’t afford to own both then sell the 85 GN.
 

TurboTGuy

Gray Beard Member
#9
My bad. Didn’t mean to offend anyone. I did the cold air conversation in my younger days and it cost me more then the car was worth. My point was just keep it as a genuine 85 GN because it’s worth more being a genuine 85 GN. And if u want an 87 then buy an 87. And if u can’t afford to own both then sell the 85 GN.
Point, and not a bit of offence taken.:D

Happy New Year!

Have a great evening.
 
#11
I did the conversion and the one thing that I didn't see here was the conversion to the 87 electric fan. I found the kit at Casper's and installed it. I had to continue to use it since the fan connection on the wiring harness was dead. Not sure why and I could never find the real reason. However, I left the 87 conversion wiring in place and have continued to use it. The fan kicks on as needed and it works well. I have the GBodyParts dual fan setup and no problems.

Hope this helps.
 
#12
I did the cold air conversation in my younger days and it cost me more then the car was worth.
Very true and it was a total PIA to find all the needed parts and harnesses. However, I guess I just looked at it as a challenge and once I started it, I was in it for the long haul. Probably won't do it again. My second 84 TType is going to say a Hot Air
 
#13
Did the conversion many years ago no big issues IF you have all the parts are you installing a 87 engine or converting your 84 engine to intercooled setup
 

INEEDAGN

Seen Your Member
#17
I did the conversion and the one thing that I didn't see here was the conversion to the 87 electric fan. I found the kit at Casper's and installed it. I had to continue to use it since the fan connection on the wiring harness was dead. Not sure why and I could never find the real reason. However, I left the 87 conversion wiring in place and have continued to use it. The fan kicks on as needed and it works well. I have the GBodyParts dual fan setup and no problems.

Hope this helps.
Depending on exact year of dash harness and engine harness, the electric fan may or may not work with the hot air dash harness. I don't know why but some report theirs works fine and others report that it didn't. It's a moot point because it's an easy fix. The actual load bearing power wire for the fan is part of the engine harness and comes off the starter. However, the 12v key-on power from the ign switch to power the relay contacts comes from the dash harness and that wire is your troublemaker. BUT. Since it's basically a no-load 12v ign trigger wire, you can acquire that signal from several places in the engine bay. I chose the evap canister solenoid wire as it was the closest. Run a jumper wire and hide it in the harness and leave the dash harness alone
 

O SO LO

Active Member
#18
Depending on exact year of dash harness and engine harness, the electric fan may or may not work with the hot air dash harness. I don't know why but some report theirs works fine and others report that it didn't. It's a moot point because it's an easy fix. The actual load bearing power wire for the fan is part of the engine harness and comes off the starter. However, the 12v key-on power from the ign switch to power the relay contacts comes from the dash harness and that wire is your troublemaker. BUT. Since it's basically a no-load 12v ign trigger wire, you can acquire that signal from several places in the engine bay. I chose the evap canister solenoid wire as it was the closest. Run a jumper wire and hide it in the harness and leave the dash harness alone
I am dealing with the fan issue right now... If you use a 87 Engine Harness, you will have no power to the relays for the fan- because the 87 fuse block had a separate fuse for the elec. fans where the 86 used the A/C fuse. Best bet is to get the 86 harness The 84-85 A/C fuse will work as well just need to find that wire in the C100 connector (at firewall) and pin it in the right place.... Which I haven't found yet. Been busy with other things.
 

INEEDAGN

Seen Your Member
#20
I am dealing with the fan issue right now... If you use a 87 Engine Harness, you will have no power to the relays for the fan- because the 87 fuse block had a separate fuse for the elec. fans where the 86 used the A/C fuse. Best bet is to get the 86 harness The 84-85 A/C fuse will work as well just need to find that wire in the C100 connector (at firewall) and pin it in the right place.... Which I haven't found yet. Been busy with other things.
Sorry but that's not correct. My engine/harness was a very early build 86 and had no key-on power to the relays in an 84 t type.

By very early build I mean one of the first couple hundred intercooled engines built, if not one of the first few dozen, based on the vin