I am trying to find out what is the correct a/c compressor for my 1987 GTA.It has a reman compressor on it now that needs replaced and I would like to put the original one back on it.I have seen several compressors with different model numbers and different styles of stickers (GM) that will fit but I am looking for the one that would have been on my car when in was new.Does anyone have a low mile all original 1987 GTA with the original compressor on it that would send me a picture?Any help would be greatly appreciated.

 

Come on,help a guy out!I am sure someone out there has an all original 1987 GTA.Does anyone know what model number the compressor should be?The model number is printed on the GM sticker.

 

Well mine isn't low miliage but I think the a/c is original. It doesn't work and I don't think it has in a long time. I'll go look and see if it has a number on it.

 

Okay mine reads.....

"Mfg by Harrison for General Motors Corp."

Model # 1131634

Code # 031071

 

 

They are all R4's. The differences between one number and the next amounts to things like a v-belt clutch pulley or a serpenting belt clutch pulley, clocking of the coil terminals, and whether or not the pressure switch port is in the compressor casing itself, or in the compressor hose manifold.

Just go to the parts store you intend to purchase your compressor from, and they can get you the right compressor for the car. I'd call around/check the web for the best price, and given that the R4 is a tough compressor to rebuild right, I'd recommend considering a new one if it fits the budget.

 

Thanks for the picture 80schild.I do know that your compressor has the original style decal on it.I'm just not sure of the model number.I have seen about three or four different compressors on 87's with the old type decal and different model numbers.I wish you knew if it were original to your car.I had planned on watching Ebay for a NOS one to come up for sell because the new GM compressors I have seen look different than the original ones.They have a different decal on them and the front and back of the compressor looks different.I just would like to to be 100% certain of the model number.I know this sounds **** but I am trying to keep this GTA 100% stock.Its a very nice 2 owner car with 63,000 on it.I figure if I'm going to spend alot of money for a new compressor I might as well try to find the original one and not just one that will work.Hopefully someone else on here will confirm your model number as the original.Thanks again for you reply

 

Unless his was replaced with a used unit, it is original. Aftermarket, and GM compressor replacements had a different decal than that one. Reman units typically have no decal at all.
Chances are pretty good all the 87's you saw with different decal numbers were original, and correct for the application. I don't know the rhyme or reason to it. I've seen identical years, identically optioned chevy trucks, with R4 compressors with different numbers, too.
Good luck finding one with that original decal. Last month, I installed a brand new, right out of the AC-Delco box, R4 in a serpentine conversion on an 84 Camaro. New, not reman, AC-Delco, from GM. It did not have this type decal you are looking for.

What are the symptoms of your AC? Are you certain your compressor needs replaced?

 

I think mine is original. Accroding to the previous owner the a/c hasn't worked in a long time, and it never was converted over to R134a. Even the hoses look pretty old. I understand what you mean about wanting to keep everything as stock as possible, mine needs alot of work and I'm trying to put as much back as original as I can. I'd like to get my a/c up and running, but so many other things needs fixing first. One thing I have noticed is that some cars have the compressor on the driver side (like mine), and some cars have the compressor on the passenger side. I wonder why they didn't build them all the same.

 

For the v8 engines, the compressor is on the driver's side for 87 and older cars, with a v-belt setup. 87 is the oddball year in that it has the same v-belt setup, but the water pump/alt belt is a 5 rib "serpentine-looking) belt.
Starting in 88, the v8 cars had a single, spring tensioned, serpentine accessory drive belt, just like all modern cars today. The serpentine mounting brackets put the compressor on the passenger side.

 

Thanks for the replys.Just wanted to let 80schild know that the compressor you have on your car is the right one.I have seen two very low mile 1987 GTA's and they both had the 634 compressor.Thanks for the picture