Just got an 87 GN!!

[Adrian87]

Hello all,
I've been an avid Fbody nut for a few years now, and have owned LT1 and LS1 powered cars. Always been in love with the Buick's, but I couldn't find one I could afford back then. Well I just sold my 98 Z28m6 and found a sweet original 87GN in KY. This thing was well taken care of, garaged, no rust, but it does still have the crappy original paint. A few questions..is has the 'Astroroof; where it retracts and also elevates upward. I've heard these are pretty rare and make the car worth a bit, especially since it has the original paint with no ruse anywhere. Has a GNX dash cluster also..looks pretty trick. The car has a few items that I don't know too much about. There is a remote knock detector inside the cabin, hooked up to I have no idea what, and some led's under the hood. With this thing on, it has never went off or made any noise at all, and I never heard any audible knock, the most I could get was 13psi boost. Car ran hard for a while until the inlet hose came loose from the turbo, (has a kenne Bell intake system) Replaced hose and tightened and now the SES light stays on, even though I unplugged the battery for over 3 hours hoping to reset the ECM. Never happend and then the car didn't seem to run as hard...next I noticed (probably from me driving it like I was used to driving my 6 speed Z28) that it had started to blow huge amounts of smoke out of the exhaust. Didn't do this when I bought it. Well we determined it was the turbo's fault when we pulled the intake system off and there was alot of shaft play on the compressor wheel.

Basiacally what I am asking is what all do I need to but to get this thing flying.

It already has an AFPR, which I don't have a guage so I don't know what to set it at. A complete fiberglass airdam attached under the front bumper with intakes for the intercooler and engine (It says Kenne Bell as well as the GNX dash that's in it) It also has airbags in the rear with one tube run out by the rear license plate. It has a cold thermostat, usually runs 150 or 160, and Kenne Bell plug wires. The trans, which has a cooler, may have been rebuilt because it shifts very positively and always barks 2ng gear.

I know that I will have to get:

Some big fuel pump (walbro 340?)
Injectors (009's or 50's)
Turbo (T60?62?)
Exhaust? Down pipe? (not even sure what that is)
Chip...ugh..there seems to be hundreds...


...basically.......HEEEEELLLPPP!!

Just need you guys to point me in the right direction. This car is pretty much a toy and I'd like it to run atleast mid 11's easily and reliably.

 

[JDSfastGN]

Alright well the whole check engine light sounds a lot like you might have left the Mass air flow MAF sensor unplugged. Check it and the connection. It might have also taken a dump, and one of the best things to do is to get a translator and LT1 or LS1 MAF. Our stock ones never last long and the rebuilts at the auto parts are always way off on calibration. It looks like you have the right idea for mods, but get a good scan tool. That is the most important thing for tuning these cars. 50# injectors sound good, but with a turbo that size you will probably have to get a higher stall convdertor. Good luck Oh and and go to www.gnttype.org and go to the spring cleaning section and that will get you started

 

[UNGN]

If the SES light is on find out what codes you have by pulling them.

A scan tool like turbolink is invaluable for diagnosing and solving problems.

Be sure to read the tech section on GNTtype.org using the pull down menus for specific topics of interest.

 

[Turbosix6]

Here is your christmas list:

complete tuneup
replace turbo hoses & vac lines
K&N airfilter w/breathers
shift kit
posi-rear
drag radials / slicks

The goods:

340 fuel pump
36lb - 55lb inj
fuel psi gauge
Houston downpipe
new exhaust or dump
John craig TE-44 or TE-60 turbo
Front Mounted intercooler (precision)
Reds 93 chip or 100 octane chip if you have the fuel avail

This will be enough for easy low 12's - mid 11's

Good luck and enjoy blowing away vettes, vipers, f-bodies and what ever else crosses your path.

 

[Pitbozz]

I also just recently got an 87 with the astro roof. My panel drops and then slides back to open it. It only 'elevates' when you are closing it. Does yours work this way as well?

 

[1987BuickGrandN]

you definately need a turbo. no worries, same thing happened to me, i thought i blew a head gasket at first, turns out it was just the turbo. it takes the right combo of things and proper tuning to make these cars especially fast. when you hit the right combo your in for some fun. if the car has higher mileage, i would suggest new valvesprings. even on an car with 80k miles valve springs will liven the car up a bit. i've always been a firm believer that true power lies in the heads. though you can make good power through the stock heads, ported and polished stockers, or some champion heads will make the car come to life. i've also herd good things about SMC alky injection. just some stuff to think about.

bryan