1985 Buick GN 6.0/4L80

wallyinc

New Member
Joined
Dec 19, 2013
I've been a visitor on this forum for a very long time, reading and learning much. I thought I would contribute a bit. I've owned my '85 GN for 7years. I'm 32 now, but a GN had been my "dreamcar" since I was 12 and would see them run at the local track.

My plan was to keep the car as original as possible, leaving the hot-air-6 intact. I worked on paint/tires/suspension and the last thing did was install a set of Dakota Digital Gauges. At this point I realized that the engine was going to a skyrocket temp of 240degrees and had 3psi of oil at idle. I looked into rebuilding the engine/turbo/tranny, but it seemed the most cost efficient thing to do was install a new engine/tranny.

I found a 6.0/4l80 combo and BRP motormounts/crossmember/header combo was used to get the engine in. I couldn't be happier with the result and I plan to put as many miles as possible on the car as I possibly can

Below are few pics showing my Buick along the way, the 4th picture is my dad with the car. Thank you again for all the posts. I'll update w/ more photos as I do more modifications.

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Looks good! I was going to go that route with an 85 but ended up purchasing an 86. If my motor ever gives out I will consider the set up you have while rebuilding the original. Well done.

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Thanks Lew_86, I'm looking to do forced induction after the first 10-20k miles. Do you have any pictures of your GN up on the board?
 
Thanks, goche4! I have much fun driving her around. Looking in the South Texas area for a custom tune right now.

hungerbuhler1, the wheels were made by http://www.ccwheel.com. Great guys to deal with, great customer service, and it's a great feeling knowing that a set of wheels are being made specifically for you and your car.

18x9.5 CCW 255/35/18 front
18x10 CCW 275/40/18 rears


I am running Continental Extreme Contact tires all around. I was really surprised how much better the car handled over the stock wheel & tire size.
 
I see in my car's log that I ordered:

F: 18x9.5 backspace 4.75
R: 18x10 backspace 4.75

I was dealing with 'Chip' over at CCW, great guy and again, great customer service, he was a great help.

I'm running completely stock suspension with freshened up bushings, shocks, and springs. I had purchased new springs (for a V6) back when the car had the turbo. They sit well w/ the heavier 6.0 and 4L80 tranny in there.

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I will get better pics of the rear as soon as the south Texas weather clears up. Only very slight rubbing on front pass. side when I hit big potholes at higher speeds, but I've had had the same problem with two other gbody's in the past.
 
I have about 400miles on the new engine in my GN. I am getting this trouble code, I've been told by other mechanics it's because my o2 sensors are located at the header collector and not on the manifold, and that a custom tune will take care of it.

Problem is that getting a custom tune is a 3-4 hour drive away and I don't think I can get away from work for a month or so, will running my engine with the system lean do any type of damage in the meantime? Thank you in advance.
image.jpg
 
The lean code can/will be caused by a leak at the header/pipe joint.
A tune is not going to correct it.
 
I like the fact that you kept the CREATURE comforts of AC:). Alabama aint TEXAS, but even in Alabama, we appreciate COLD AC. Great job. Tell more more about the AC adaptation.
 
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