convert 84 to 87

[zues1]

hey guys i have a 84 t type and 87 grand national want to put 87 drive tran in what all is involved changing wiring harnesses etc 84 has digital dash 87 doesnot will this be a problem thanks

 

[garrett]

conversion

I'm not sure about the wiring, but what are you doing about the oil return? I had a #10 AN fitting welded to the passenger side of the oil pan. I then had a duplicate AN fitting welded to the flange of the 84 stock metal oil return hose. I connected the two with hi-temp oil hose. It works perfectly. Some people say to drill the block, but this made me nervous. I don't know if the engine would have to be taken apart to get the pieces of metal out or not.

 

[Jdsluckybu]

yes i would like to know more about this oil return topic

 

[garrett]

oil pan

The other thing that I like about doing it this way,is that I was able to remove the oil pan for the modification without jacking up the engine or unbolting the motor mounts.

 

[Instro84]

mine had a digital dash also, but i mahe a panel for autometer gauges awhile before i converted. i dont think it should be a problem, you could check with John Spina at caspers and he'll let you know for sure. hth

 

[zues1]

conversion

if im using complete 87 motor&trans what issue will i have with the oil return? what is different from 84 to 87 wiring harness etc do i have to change complete under dash and all thanks for any help

 

[garrett]

conversion

I didn't realize you had a complete 87 drivetrain. I thought you were doing the more common update of the hotair motor to the serpentine system. Just for future reference, save the hotair motor for a spare, if you have room.

 

[garrett]

wiring harness

The wiring harness is completely different. The hot air harness is routed and designed to be in the front of the engine. The 87 engine harness goes around the back of the motor. The hotair harness has no air temp sensor, cooling fan harness or relays. The coil pack plug is different, the TPS is backwards, the IAC harness will need to be longer, the grounds are in the front of the motor on a Hotair. The crank sensor is totally different and so on...

 

[conn84gn]

If you have the 87 engine harness it will work with the digital dash
you are only changing the engine harnes so not a issue.
You do not have to touch the dash.
Do you have Hydroboost brakes?

 

[zues1]

84 to 87

thanks guys i have 2 compete running cars just wondering what all is different that i will have to change thanks

 

[zues1]

conn84gn yes it has the hydrobooster

 

[conn84gn]

Do you have a 87/86 engine harness?

 

[garrett]

hydrobooster

Keep The Hydroboost

 

[zues1]

yes i have the 86 87 harn the 87 gn running driving just a basket case (project gone sour)interior out sat in body shop 2 years but everything came with car bought 84 t type week ago solid complete car but has rattle in motor thought easier to do motor swap than restore car is trans,rearend etc same have 86 gn to help with swap kinda new to buicks had mopars 15 yrs got rid all of them got into buicks lot more fun thanks

 

[conn84gn]

Take everything you need off the 87 I did the same thing on my 84 GN
If you have the 87 car then it's a easy swap, time consuming yes but everything is pretty much a switch to the 87 stuff.
Area's that you need to convert that's different.
As you get into it
1.fuel filter, put it on the end of the hard line by the A frame then have a SS braided line made to connect to the fuel line running up the block to the fuel rail or go direct to the rail with the new SS line. I have pics

2. Convert Hydroboost to the 87 power steering pump. I have pics

3. Electric fans, with the hydroboost you will need a jumper wire to run the fans, pics again if you need.

4. Take pics before and as you disassemble and bag and label the parts so it will be easier to reassemble on the 84.

5. heater core use the 87, or do like I did and get a S hose from a Auto store.

Save everything on the 87 you don't need and sell off the good parts.

PM me, and I will give you my telephone number if you want.

End results

 

[zues1]

hey is there any difference in trans or rear end thanks

 

[imjoesnuffy]

Trans is a BQ not the BRF. Can be used without issue. Some would even argue there is not much difference between the two. Rear end is the same.

For those asking about it earlier, I had my hot air block drilled for the oil return. There is a pad raised on the block in the exact location as the turbo 109 blocks. I did mine this way as it was being rebuilt and bare at the time.

 

[Hot Air]

I've done the conversionb as well. Let me know if you have a question. PS...take a lot of photos of the 87 BEFORE you pull it out of the car!!!
Conrad
North Carolina

 

[conn84gn]

My 84 block is also drilled in the same location as the 87/86

 

[zues1]

conversion

hey guys appreciate all the help take alot of pictures but i also have the running driving 86 gn to go by thanks alot