BUILD THREAD 81 Buick/Olds Turbo Wagon update 08/16/23, ROLLER CAM!!


Comic Book Super Hero
Well, I have a VERY long thread on maliburacing. But this is a G-body, and I see a lot of long roof lovers here so...

It's gonna take a while to get this thread up to speed with where I am at in the build. You's guys can always view my cardomain page for ALL the pics. :mrgreen:

This started in September 2008. I've had the car for 2 years now, but I hung onto for the longest time since I was unsure if I was going to keep it, or cut it up and keep my Malibu.

I sold my 1978 El Camino SS . I picked up a 81 Buick Century wagon to replace it. My brother and I got the wagon for the parts, since it has a complete 86/87 GN drivetrain. Motor, trans and rear.

I ended up keeping it. My Malibu wagon is getting gutted, and all the new part that were on that are going on this.
This is more of a pro-touring style build. It'll have power everything, a/c, killer j/l and PPI stereo from the Malibu, car computer, Dynomat, fiberglass door panels, custom front fascia, bodykit/ground effects/rollpan (UPDATE Aug 2013, Using an Olds front clip no ground effects!!!). 18 inch wheels.

I already have AFCO front and rear springs, stiff. Adjustable spring cups, all the body and frame braces. Big front and rear sway bars. I boxed the rear UCA's and LCA's. Quick ratio steering box, jeep steering shaft. All new bushings, tie rods, center link, etc. 4 wheel disc brakes. I have a GP dash, custom insert, Autometer Phantom gauges. Custom 3 gauge A-pillar. The list grows. Over the coarse of the thread I'll post all the pics, by the time I am up to date you can see where I am at now. Again, one could always check out my cardomain, or check out the 22 page thread a maliburacing.

As far as how it ran when we got it, I was VERY disappointed. The person who did the conversion did a hack job on the wiring harness. The ECM was bad, the MAF was bad. The turbo was shot. The exhaust was falling off. None of the warning lights in the dash worked My 'bu wagon is 4000 lbs and runs a 13.6 with a 2.1 60ft, and is faster than this thing. I am disappointed actually. It'll see 24lbs of boost on the gauge, has an adjustable FPR, 30lb injectors, cold air intake, plenum spacer, manual boost controller and came with an ATR pitbull chip, and a hypercrap chip. Apparently there was a nitrous backfire, then fire, so the wiring and turbo got smoked. I found this out 2 weeks ago.

So far I fixed the wiring, got another ECM and modified so I can burn new chips for it. Fixed the MAF. Replaced the turbo with a low mileage stocker, cleaned a quart of oil out of the intercooler.

PICS from 08SEP08

When I first got it, I couldn't move it to get better pics since I had the intake tubing off to prepare for the turbo replacement. You can see the roof is pushed in, since been fixed.







I ripped this 6 banger apart some. It wasn't running real good. The BLM's on my scantool (snap-on MT2500) were at 148, running lean. The drivers side header was cracked pretty bad between cylinders 3 & 5. Someone had tried to repair is using brass rod. haha, It had a bunch of gold boogers on there. So a few hours later I ground that crap off, and welded the header up using my little Lincoln MIG with .030" flux core. PITA, wish I still had my fathers MIG here. anyway, the PS headed was cracked at the bellows. Welded it up. I forgot to take pics of those repairs. I pulled the intake off and it does look as if the intake was leaking. The gasket was a steel valley pan and there was lots of oil between the surfaces.




I bought a new Felpro valley pan and then I used a center punch to divot the entire endrails on the block and intake. I uses the RightStuff for the endrails and the divots help keep it in place.

Here is the underside of the upper plenum. If you look close you can see I started to hog out the spacer. I used to be like 1 inch wide, sticking into the plenum area.


Turbo inlet. You can sorta see how I ported the inlet and it radius' into the compressor wheel. Sorry for the crappy pic.


I picked up some free 3 inch stainless Magnaflows from a fellow military member, and I got a jet hot coated 3 inch exhaust for it too. I'll be building a stainless steel downpipe for it, but that is in the future. I haven't done anything with the valve covers or plenum at this time. We had a bunch of big military honchos doing an inspection at my base, so working on personnel stuff was out.

What I need to do now is find a junk factory cat converter, so I can cut the oval flange off it. I need to make a "test" pipe to mate the exhaust to the downpipe.

Here is the engine back together with new intake gaskets, valve cover gaskets, etc.. I powder coated the valve covers and upper plenum red. I ported the TB bigger and the upper plenum to match. Gasket matched the lower plenum to the heads as best I could, the bolt holes are way bigger than the bolts from the factory so it wasn't possible to get them dead on.

Assembled engine:




I fixed all the lights, wiring, heater, a/c, I put a floor shift column in it.

I converted to the new coil packs, type II. I need to get a new up-pipe, have some 3 inch stainless, I may make it 3 inch. I got another EGR valve, another MAF with one screen. Mounted the PS reservoir up higher. I want to make a nice bracket for it. Put delay wipers in it with the switch in the turn signal stalk.

I popped the HUGE dent out of the roof, I need to replace the inner roof braces though, they are smoked.


Here is the 3 inch mandrel bent dual exhaust. It is thermal coated. Pics of the 3 inch stainless Magnaflows. I made a "test pipe" for it too.




I took the weld wheels off it, I'll keep those if I want to race it. For now, I threw some rallys on it I had laying around. I'll be putting the 17's from my 'bu wagon on it.


I bought a turbo tweek chip, 18 lbs boost for 92 octane. Took it for a ride and MAN :rockon: this things hauls. WORLD of difference from the way it was when I got it. Looking at some of the dudes on turbobuicks, they are all high 11's, low/mid 12's with stock longblock set-ups like this. I have the intake, exhaust, the chip, plenum spacer. I wanna get what is called a power plate, put the nitrous on it, and an alky kit. If it doesn't run low 12's high 11's, something is wrong. All with 20+ MPG cool.gif
I picked up a polished up pipe, a heated Caspers o2 sensor.

Newer engine pic


Casper heated oxygen sensor kit


Polished Up pipe


RJC PowerPlate yet to be installed as of these pics.

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Comic Book Super Hero
Re: 81 Century/GN Wagon build-up 56K beware!!

At this point I fixed and installed the headers, downpipe and exhaust. The gas tank was junk and leaked. So I bought a new one from, and started to modify it with a sump and well to keep the pump submerged. I started to install the Powertrax locker unit in my 9"in.

I have a 9 inch axle from QP, I installed a backbrace on it. My Malibu wagon has rear discs that I made, so I'll be migrating those over to the 9 inch to go on the Buick.

The car was running pretty good here, but I still had a bunch to do. The engine leaked everywhere on the bottom, the trans did, the floors needed some repair. Keep on reading so see.

I am trying to post these in order that I fixed the stuff, but I may have forgot some details.

More pics of the parts I powder coated




Control arm braces. Gonna re powder coat these. Anyone have the bolts or the specs so I can buy em?


Intercooler scoop. I am gonna clean it up and fit it, the make a inlet to go from the airdam to this.



Here is the RJC powerplate for the Turbo Buick. In the pic, in red, is a square hole I had to add to keep the EGR functioning when I take the plenum spacer out and put this in. I just center punched 4 corners so I can drill a 3/8" hole, the connect the dots with a file.



After drilling the holes on my drill press.


After filing the sides smooth and cleaning the carbon of the plate.


This is a 3rd gen/4th gen Camaro (can't remember) fuel pump assembly. I tried modifying it to fit in the fuel pump well of the stock wagon tank.


After taking it apart some.


Here is my Ford 9in open diff. The gears are 3.50's, the axles are 33 spline.


Here is the Powertrax unit that is going in it.


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Comic Book Super Hero
Re: 81 Century/GN Wagon build-up 56K beware!!

Since we all know that the G-body Wagons never came with fuel injection, I decided to make a custom fuel hanger and tank for it. My Malibu had a sumped tank, but under 1/4 tank it would suck air and stall. I can't have this with a turbo engine.

In work we have a machine shop. I wanted to make an aluminum top for the fuel sender/pump hanger. So we had some 7075 t651 aluminum bar stock, 4 inches. i cut a thin piece off, then chucked it in the lathe to turn it to make my top plate. Got 2 -6 and a -4 an bulkhead for the pressure, return, and vent. Now I have to get bulkhead connector for the bigger FP wires and a sender wire. Then hang the pump hanger from it. This is made so I can convert it to a double pumper anfter the car is done. I used a Walbro 255 LPH pump for it.

Hear are some progress pics.









Here I put together the first iteration of the fuel pump assembly and I couldn't go that route. The pump bucket is to big to fit in the hole with a sender arm on it. I tried clearancing the hole in an old junk tank to try it out, but it is so tight that once I get it in I have to fight to get it out. Oh well, back to my original plan.

Don't mind me red fingernails, my daughter and niece painted them when I passed out drunk! :lol:




I painted the 9 inch differential. Not sure if it will stay red yet, but all the other misc crap under the Chevy wagon is red, and the Buick is red so...


I put the intercooler scoop on. I plan on redoing the Malibu tucked front bumper and the air damn to fit the Buick, closing the outer 2 slots in the air damn and opening up the center panning it to the intercooler scoop.




Don't worry, I straitened it out after these pictures were taken!

I had some excess material to cut off of the muffler hangers, so I did that real quick too.


The I pulled the upper plenum off, got rid of the half in plenum spacer, and put the RJC power plate in. I also painted the allen head bolts before they got all rusty.



Here is the relocated IAC



Here you see the Type II coil pack conversion.


Here is is back together


After is was all back together, I re-installed the new cam sensor, set the Idle to get the correct IAC counts, the re-adjusted the TPS. runs good so far.

I also pulled the flexplate cover, I need to order a new rear main seal, pan gasket, and front pump seal to start sealing this engine up.
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Comic Book Super Hero
Re: 81 Century/GN Wagon build-up 56K beware!!

Went to the U-Pull-It, picked up the jeep steering shaft, should be the right one this time ](*,)

Here it is, I'll try it first before painting it. I noticed the slightest bit of play with the inner shaft and outshaft, anyone else have this? probably less than the rag joints and worn out old shaft though.


I got a balancer, ignition module, crank sensor and wiring harness from a 1998 Pontiac Grand Prix with the 3800. I am going to do the "Fast Start" ignition conversion to it, so it starts faster. I got the info for this mod from Turbo1dr. :rockon: See here---->Fast Start


Here is the Spectra gas tank!! :eek: Here are a few pics. I will scribble something real quick and scan it so you all can see my anti-surge idea for it.





Added a really quick MS paint sketch, let the wise cracks fly, LMAO :lol: This was the idea for the internal anti-surge well, IOW, keeping the fuel pumps submerged in fuel.


The pipe will only be big enough for 2 pumps, and without the socks getting messed up going in it.

I yanked the old tank to mock the new one up. The filler neck was WAYYYY off ](*,) I have to heat it up and re-solder it in the right location. Then I marked where the pump well is gonna stick through the bottom of the tank, then made a cardboard template of wheat the resevior will look like. I may also have to clearance the tank for the # inch tailpipe, it is a bit close. i had the tailpipe on the Malibu Wagon rub a hole in the brand new tank I have to fix, not fun! #-o

New Pump kit


Jacked up filler neck


Sump Mocked up in cardboard



Close tailpipe


Temporary mounted tank


Hole marked


Sump Mocked up


I'll weld some bungs in for future expansion if needed.

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Comic Book Super Hero
Re: 81 Century/GN Wagon build-up 56K beware!!

The Turbo Buicks had a heat shield right on the Evaporator box, this didn't have it. So I sourced one from a member of turbo buicks message board


Steering shaft pics



Some work on the Pump.


I have to put a bump in the pressure line so I can clamp the hose on. Then solder a wire to the float ribbon. I took a strait AN bulkhead and hogged out the center to fit four wires through it. 2 power for 2 pumps, a ground and the sender. I'll get some gas tank epoxy and load it up in side, then add some heatshrink in the tank side over the wires/AN intersection. There wire is the expensive aircraft wire, can't remember the spec, but it is good for fuel. Problem is is they are all white, lol, I just have to label them good.

As I said earlier, I was gonna run a few wires thru a hogged out AN bulkhead fitting, but I didn't really like it. So, I did what was suggested to me by someone, and used a 1 inch counter bore on the bridgeport in work and counter bored a spot to put a factory style plug in there. When I go to upgrade to double pumps (need cash), I'll get the bigger harness from racetronix.





Then I decided to fab up the double pump mount. I realized this this set-up was no good, the one pump was rubbing on the sender. #-o


Then I looked at the Racetronix site, and saw how they did theirs so I drew a quick sketch, I'll make one myself tomorrow out of stainless. Racetronix had one for 35 bucks, But I can make during work and get paid for it, lol.

This is how it sits right now, I put a few bends in the tubing for a better fit for everything, when I make the mount I stick it on, and leave it for the future. I didn't add the second pump outlet yet, there will be another hole added for the vent (-4AN), and I'll open up the existing -4 hole for another -6AN bulkhead fitting.
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Comic Book Super Hero
Re: 81 Century/GN Wagon build-up 56K beware!!

Here is a factory wagon pick-up with the sender removed.

Here it the measurement from the bottom of the flange to the center of the sender, the arm pivot. It was 7 3/4".


Here it is on the new assembly


The arm is about 6 3/4" long


The start of the arc for the swing of the float


The top of the arc, around 10" (maybe 9 7/8")


The tank is 12 3/4" deep RIGHT below the hole. But as you can see from the first pic, the sender actually angles towards the back, keeping the float towards the center of the tank. Our setup makes the float more forward where the tank is a bit deeper. That's ok though.


Here is the factory coupe/sedan sender


Here is the arm in the tank, the pump won't got in. ](*,)


Here is the pump in the tank first, the arm won't go in. ](*,)


I haven't decided on what to modify to get everything in the tank, but it'll work out! :twisted:

Oh, and when the float is at full, it is like 1 1/2 inch from the top of the tank. So whet it is on E, there is still 2-3 inches of gas on the bottom. I like it that way.
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Comic Book Super Hero
Re: 81 Century/GN Wagon build-up 56K beware!!

Here is the new tank getting hacked up to make my anti surge well. I tought myself how to TIG weld a few days before this, using the TIG welder in work

I also sandblasted a few of the bucket seat floor mounts and console mounts, I still have like 4 pieces to go. I also sandblasted and painted one of the rear control arm mounting point braces. This weekend I will take the harmonic balancer off of the engine so I can take it in work and put in on the lathe, so I can machine the backside flat for the relucter rings for the fast start mod.

I had to cut the bottom of the tank off to get rid of the crap I did the first time

I mad a piece of metal for the hole

Here it is tacked in

My second day TIG welding

Here is the new standpipe, take 2. (*,)

All welded in

The hole marked out, again curse_sign.gif

A few bucket seat/console floor brackets

Control arm brace all scratched up and rust spots

One sandblasted and in etching primer

Same brace painted with ceramic red paint. (powdercoating oven in work is broke)
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Comic Book Super Hero
Re: 81 Century/GN Wagon build-up 56K beware!!

Here is the tank finished up. I made the pump well and the sump. Welded it up and pressure checked it. Put the fuel pump/sender assembly in it and painted it up. I used Etching Primer and black ceramic paint.











After I finished welding it and pressure checking it, I went to the balancer so I can turn down the snout to fit the 18x and 3 x relucter rings for the FAST START ignition. Then I brought it home, cleaned and painted it. I still have to fit it on the car and make sure the rings don't rub or hit the crank sensor.






The welders I was using



Just a shop of the weld shop

I know I don't have perfect looking TIG welds, but it doesn't leak and looked fine when I painted it over. I didn't need to clean of any dingleberries or anything.
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Comic Book Super Hero
Re: 81 Century/GN Wagon build-up 56K beware!!

I had a few extra transmission pans laying around for the 2004r. I decided to make a 1 inch deeper pan, this will give me a bit extra fluid, and the ability to use a bottom feeding filter. These transmission have known issues with sucking air under hard acceleration. This should combat that problem.

Pan one.

Pan two

Getting cut

Bottom cut out of one

Bottom cut out of two

Test fit

Test fit

I am just going to slid one over the other and weld. The pan tapers smaller from the mounting flange to the bottom so it is pretty easy.

This is my donor passenger side floor pan from a Monte SS I cut up a long time ago. I'll be getting the rest of my seat brackets, a piece of the floor brace, and a few piece of the floor itself for patches. I also to some measurements of how far the brackets are a part, if anyone needs it.


Got them out

The other ones

Sitting one the floor pan

I also to the drivers side power seat track and mounted it to the drivers side bucket. I think I'll end up fabbing a trim plate for the front lower portion of the seat to mount the switch out of site, but accessable.

power track

Seat bottom

Just sitting in the car for now

And finally, I made it so I can get the reluctor rings off of the 3800 damper, so I can do the FAST START conversion.
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Comic Book Super Hero
Re: 81 Century/GN Wagon build-up 56K beware!!

Here I am doing the FAST START ignition conversion. I pulled the cold side piping, intercooler and crank pulley, and the balancer. The pulley is an underdrive. I mounted the newer 4 wire crank sensor, I used a non adjustable one. Then added the fourth wire to the harness, added a relay so I can hotwire the ignition module. This just ensures that the module and coils get 13+ volts while the engine is running all the time. Everything is soldered and heat shrinked. I don't use mechanical connectors if I can help it. Now the pics.












I am mounting the relay for the module hotwire under the module/coil bracket. Trying to keep all the junk off the firewall. I never got to splice in the newer module plug. I'll attempt to get that squared away during the week when i can get out there.
Here is the crank pulley too.


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