Unmodified and untouched

You need a new fuel pump, chip, valve springs, timing set, and power wire for the pump at a minimum.


Even though your car is low mileage, those parts are over 30 years old and they've timed out (and some of them were bad back in '86.)
 
The original plug wires were numbered 1-6 So you might wish to keep them for car shows. However Highway Stars sells new ones. If it has the original tires you need to replace them as they do dry out and "expire" like milk. Also if your fingers turn black from the hoses, it's time to replace them too. The powermaster is a ticking time bomb. Not worth risking your life for originality. Does the ac blow cold? I see it has the original (black) drier. And last, do a search on zddplus. It replenishes the missing zinc in today's oil. It was created by a gn fanatic (and all around great guy).
 
It wouldn't be a bad idea to add an oil pressure gauge and water temp gauge in a pod in center console if u plan on driving the car. Looks practically factory. Ford liked it so much they put the gauges in that spot in their Mercury Marauder. Well at least that's my opinion.
 
I also have a 1 owner 28k mile original car. Yes its going to stay stock but not over certain things that need to be done. Saftey first, mechanical saftey second. Belts, hoses, brakes number 1, Like earl said timing gears, chip, fuel pump and wire kit. If you dont think so wait until you stand on it and loose fuel, or your timing
20150322_210728.jpg
gears let loose. How stock will it be then??? Here is a pic of ur plastic timing gear..they start to disintegrate after time regardless of ur driving
 
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I also have a 1 owner 28k mile original car. Yes its goning to stay stock but not over certain things that need to be done. Saftey first, mechanical saftey second. Belts, hoses, brakes number 1, Like earl said timing gears, chip, fuel pump and wire kit. If you dont think so wait until you stand on it and loose fuel, or your timing View attachment 311915 gears let loose. How stock will it be then??? Here is a pic of ur platic timing gear..
Wow you must have really hammered on that car, loading it on and off the trailer Lol!
 
The MAF's had a tendecy to fail so keep that in mind. OEM replacements are getting hard to find and reman's just don't hold up. Most convert to the modern LS MAF's for reliability reasons.
 
I woudlnt second guess the factory Bosch fp regulator or the factory boost control strategy since they both work very well. Replace the factory wastegate hoses with NOS hoses and if you want to update the chip get a fuel pump and Hotwire for it. Have the chip burned for the fp regulator you have. All can be done with no cutting and can be returned to 100% stock


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Congrats. I know what you mean. I bought mine May 8, 1986 and today it has 4560 miles on it. Wipers have never been turned on, don't even know if they work. I'm a little anal about original but the time has come to replace a muffler. I have a service parts exhaust system purchased in '89. I still look for service parts (have a bunch) but they are hard to come by this late in the cars life. Good luck with yours.

edit signature to 4500 miles. It's been a while.
 
In addition to what Earl said if you plan on keeping the stock MAF I'd get a spare and keep it in the car. If you get one that's a reman. try it out you may have to exchange it a dozen times or so before you find one that's actually good. The original MAF will fail and could leave you stranded.
 
Hello fellas, I have a low mile 87GN all original. One of the things that I saw throughout the forum is how much the rear seat brace helps to reduce flex and improve drive quality. I have been going back and forth on what direction I should go (Install, don't install). I would have to obviously drill some holes. I don't drive it often nor get on it real hard when I do, but I also don't want B pillar cracks showing up some day which is what I heard can happen to the GN's. My question is do you all think it will reduce value by installing these? I guess I need to ask my self whats worse, B pillar crack or reducing its value a little by installing the seat brace.

Appreciate any feedback

Thanks,
Curt
 
No drilling necessary for rear seat frame braces. The holes are already there.
 
No drilling necessary for rear seat frame braces. The holes are already there.

This may be true for the tubular X bracing, which may be a better option for you. I don't know how they compare to each other.

When I installed my GNX brace (made by Kenne-bell) in '89 or '90 it was necessary to drill holes in the seat back brace as well as 4 (I think) through the floor.

Maybe the design has changed since then.

I've also heard of guys welding it in place, which could be ground off to return the car to completely stock.

Just some thoughts.
 
Hello fellas, I have a low mile 87GN all original. One of the things that I saw throughout the forum is how much the rear seat brace helps to reduce flex and improve drive quality. I have been going back and forth on what direction I should go (Install, don't install). I would have to obviously drill some holes. I don't drive it often nor get on it real hard when I do, but I also don't want B pillar cracks showing up some day which is what I heard can happen to the GN's. My question is do you all think it will reduce value by installing these? I guess I need to ask my self whats worse, B pillar crack or reducing its value a little by installing the seat brace.

Appreciate any feedback

Thanks,
Curt
I purchased my 18,000 mile T last April, after a couple drives, it could not hold a candle to my 84 Grand Prix. I installed front frame braces, fender braces and rear X brace, could not believe the difference in handling and ride quality, and those annoying squeaks and rattles, GONE!!!!
Just my opinion, but I would not hesitate to install all available braces, and all the body bushings.
 
Thanks for all the info guys, appreciate it. I just popped the truck to look at rear seat area again and I do have some holes there that I could probably have some one fabricate a bolt on system to accept some type of x bracing. Holes are quite large though on the center vertical piece. I had purchased the Kirban 4 piece rear X brace kit a few months back but had seconds thoughts on installing. They do not line up with the existing holes and I know they do require some drilling. I think I heard the grand prix had them installed from the factory, not sure if they used pre existing holes for bolts or were welded. I do have the front three triangular braces from Kirban. Those were bolt on and made a big difference in the front end. Simple unbolt to return to stock. I still have the pesky rattles and squeaks thats why I am just looking for options for the rear seat brace. I also saw online a bolt on system that connects the rear frame ends together. They are from GNS performance (G-Body Rear Frame Brace Brackets) Link is below. Anyone try these yet? Curious if they would perform the same function and provide the same results compared to any of the rear seat brace.

https://www.gnsperformance.com/bodyframe-g-body
 
Absolutely beautiful car! Congrats. Having once had a near factory original GN up until a few years ago I can appreciate purists like yourself trying to keep these cars as close to original as possible. I was once one of those people but gave up because it became too difficult to maintain factory correctness in the "truest sense" as the years went by and parts needed replacing. For example, that alternator you have is not factory correct with that gold colored stator. It should be black. Good news is you can actually get a new correct appearing one if you so choose, unlike some other parts.

Also, the passenger side powermaster reservoir appears slightly overfull. This is important to know because not many people outside the Turbo Buick world knows how to work on this funky brake system. If someone were to depressurize the system as it sits now with it overfull, it would puke brake fluid from the lid. And if you got any of it on your paint, well, we all know what happens then... Don't get me wrong, I'm really not here to pick apart your car as it really is a beautiful example anyone would be proud to own. I just thought I'd mention these things since you seem the type that would want to know.
 
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