PROJECT - Restoration of 1972 Opel GT Download

[newman27]

<The first of three posts on the ADDCO anti-sway-bar install is on the prior page and includes links to the ADDCO web site>

We installed the rear anti-sway-bar first. The ADDCO rear anti-sway-bar (5/8” diameter, stock number 902) came with directions marked as Revision 1 dated January 17, 2000. The first step was to find the pre-drilled factory holes in the frame, which were present but covered over in primer and paint. Once these holes were revealed, we attached the brackets to the frame. Next, we assembled the end-link with spacers and lined these up to locate the holes we had to drill in the spring support. Once the holes were drilled and everything loosely attached, we tightened everything up.

A few notes to keep in mind:

• The illustration included in the directions indicates that the anti-sway-bar “bend” is to run under the drive shaft. However, we ran the anti-sway-bar bend above the torque tube, as it would not clear the other way.
• Make sure you run the bolt for the bracket that attaches the end-link to the spring support such that the head is on the inside of the spring support with the bolt shaft sticking out. Tighten the lock nut on this bolt and then cut the excess off with a hack saw so that the end-link bolt and spacers will clear. You don’t want this bolt sticking into the spring support area.
• When lining up the end-link location for mounting, jack up the frame of the car with the wheels still on your ramps. By expanding the springs, you are allowing for travel in the suspension with the anti-sway-bar in place.

Matt

[newman27]

We installed the front anti-sway-bar second. The ADDCO front anti-sway-bar (3/4” diameter, stock number 140) came with directions marked as Revision 1 dated January 17, 2000 (same as the rear). The front anti-sway-bar install was slightly easier than the rear. We started by checking the bolting pattern for the end-links. Next, we located and marked the spots on the frame where we would have to drill to run the U-bolts. We checked the U-bolt alignment and then passed them through the frame so that the threaded ends protruded outward. We then attached the brackets to the frame. Next, we lined everything up to find the right spot to drill mounting holes in the A-arms. Finally, we mounted the anti-sway-bar end-links to the A-arms to complete the installtion.

Just one thing to note here:

• The directions say to drill 3/8” holes in the frame to pass the U-bolts through. We had to drill 1/2" holes in order to be able to pass the U-bolts through.

Matt

[newman27]

I had the latest upgrade to my car installed at Kauffman Tire yesterday in the form of some classic looking Cooper Cobra Radial G/T tires (205/60R13). These tires replace the Blue Streak 185/70R13 tires that I had on the car. The additional 20mm in width further improves traction (tested thoroughly on the way home) while shedding just 6.5mm in sidewall height. Combined with the anti-sway-bars, I can really take the corners now! Finally, I think the white raised lettering will give the car a little "meaner" look when it's hob-knobing with muscle cars at the next car show. I want to thank Gene for the suggestion and for helping out by tracking down four of these tires through Kauffman Tire. Gene even took my old set of tires off my hands .

Matt

[newman27]

Today marks one year since the Tennessee Dyno Days 2007 meet where I picked up my GT so I have to mark it with a post back to the PROJECT thread here...

The past year has been a BLAST!!! I managed to put ~6,600 miles on the car for an average of 550 miles per month (50 miles more per month than I had estimated). The odometer sits at 98,683. The longest trip taken was to the Nationals in Charlotte which was 534 miles round trip averaging 27.23 MPG. It looks like with my heavy foot I get about 19 - 20 MPG around town and have gotten as high as 36.76 MPG on the highway. My top unverified speed reached so far is 108 MPH on the way back from Nationals and the car had plenty more to give.

I've been keeping a very detailed journal on the GT and that has helped tremendously as far as being able to go back and check what has been done and also plan things I want to do. Basically, the only significant issues over the past year have been with parts not replaced as new at the time of restoration (fuel pump and water pump being the two primary parts that failed both of which were used). An inner tie-rod also failed. Replacing those and also upgrading a few things here and there has really taught me a lot about the car and I feel a little more self reliant now.

That said, I still have to ask for help and so I want to thank Keith Lundholm for taking all my calls and helping out with phone support. He even made a house call to Atlanta a couple months after I picked up the car to help tweak a few things! You did a great job Keith! I also want to thank the Georgia Opelers for some great times over the past year! I especially want to thank Gene Smith and John Lewis for helping me out locally again with questions and ideas for changes. John also helped me swap out that inner tie-rod that went bad and ran a bunch of diagnostics on my car to tweak the tuning now that the engine is broken in. The car is running better and stronger than I ever even imagined possible! Thanks guys!

Anyway, it has been a very good year and so here's looking forward to the next year!

Matt

[newman27]

I'm continuing to use this thread as a "blog" for upgrades made to my GT...

Christmas 2008 was very good to the GT; see the first photo for what Santa left under the tree. For starters, I purchased a new chrome brake reservoir cap and polished thermostat housing from Jim at USA Opel which added some "bling" under the hood. While I had the thermostat housing off, I tested the thermostat and it wasn't really opening completely even at 212 degrees so I dropped back to a new 160 degree thermostat. Auto Zone has the Duralast brand 160, 180, and 195 degree thermostats all in stock and these models have the "burp" valve built too. This lowered the operating temperature of the car from a range of 1/2 to 2/3 on the TEMP gauge to a much more desirable and consistent 1/3 (occasionally creeping up to the next mark but never reaching even 1/2 now). This is a pretty big drop in running temperature and I have a more steady reading. The old thermostat may have been in the early stages of failing. Sometimes making a cosmetic change has unexpected benefits . Part 2 of Christmas 2008 to follow...

Matt

[newman27]

OK, now the part I'm really excited about. I finally managed to get my CAI installed which has been high on my priority list for some time. I basically copied a design that I first saw posted by George Rust (opelenvy) but made a couple changes too along the way:

1. The vacuum hose running to the valve cover uses the 90 degree PVC tube installed in the base plate of the adapter housing
2. The J-bend pipe extends into the nose of the car a little further and is parallel to the radiator

Thanks George for answering my PMs - you were a big help! .

There has been some debate about whether or not you can improve on the stock GT air intake when used with a new K&N high flow filter. However, I think this design blends performance and good looks. What's more, the side benefit I hoped for, a lowering of the exhaust note to more of a "grumble", was achieved . I had to make a small cut in the opening to get the 3" Magnaflow J-bend pipe through but that wasn't too difficult. Actually, the hardest part was making two cuts to the Magnaflow pipe with a hack saw. My arms were pretty tired after that. Anyway, I think this turned out rather nice and I had fun doing it!

Matt

[newman27]

Today marks two years since the Tennessee Dyno Days 2007 meet where I picked up my GT. I'm continuing to use this thread as my personal "blog"...

The past year has been even more fun than the first. I managed to put ~5,078 miles on the car over the last twelve months for an average of 423 miles per month. Average monthly miles declined a bit over the prior year because we got a new family car (Pontiac G8 GT) which temporarily replaced the Opel GT as the "fun" car for a few months.

The odometer completed its first "roll over" to all zeros on 12/06/08 (with Keith Lundholm in the car with me at the time appropriately enough) and now sits at 3,761 miles (103,761 total miles). The car has gone 11,666 miles since time of restoration. I am averaging about 22 MPG around town and have gotten as high as 32.02 MPG on the highway this past year.

The longest trip taken this past year was to the Madison, AL "EuroBrit" car show which was 673 miles round trip (the car averaged 27.24 MPG). This trip was really special because it was just my wife and I on the open road driving a classic car, staying at a bed and breakfast, and taking in some great scenery in Alabama. The car show itself was top notch and capped off a great "long weekend" vacation.

Speaking of car shows, I entered four shows over the last twelve months and took awards at two of them: "Classics In The Country" in Oconee, GA and the "EuroBrit Car Show" in Madison, AL. I scored a 99 / 100 at the show in Monroe, GA where I took an award the year before but was edged out for a trophy by some other really nice cars in the foreign and orphan classes.

I learned some new things about maintaining the car including replacing an inner tie rod, refreshing the speedo cable drive and seal (eliminated a leak), swapping out the electronic ignition, jetting the carb, changing the thermostat, installing a custom CAI, adjusting the transmission "ball stud" and clutch release lever, and installing a new clutch cable which snapped on me a month ago. As always I have this forum and several members in particular to thank for helping me learn more about this car: Gene Smith, John Lewis, Keith Lundholm, and Harold Collins come to mind (I really hope I don't forget somebody that may have answered a thread or a phone call over the past year). Thanks all!

As far as upgrades - the CAI install was the primary performance upgrade along with some tweaks to the carb and ignition system that John Lewis helped me with. This made quite a difference. I know all Dynos are different and even vary day to day, but I pulled 97.23 BHP in January, 2009 at a local Dyno shop in Cumming, GA. In the near future I hope to get time to install a Sprint manifold I got a great deal on from Steve Goines (thanks again Steve!).

It's been a great year and a great two years. I've now owned this car for 23+ years but have driven her more in the past two than the prior 21 and that is a great feeling!

Happy Opeling!

Matt

[newman27]

Continuing to document my GT upgrades in this thread... If you have comments, please see the link to the comments thread in my signature.

The past two weeks were good for my GT as two upgrades were accomplished. First, I installed the OGTS Oil Temp / Volt gauge in place of my non-working clock. I did most of this install myself but needed help at the end from John (guyopel) to get the sending unit installed. I couldn't get the oil pump priming plug out. What I did here was take the +12v lead that was going to the clock and split it to power the the two new gauges. I was able to use the existing clock ground wire. A new wire had to be run to the Oil Temp sending unit. At the fuse block, I had to move what was the clock +12v from the "always on" location to a switched location. Unfortunately, I was out of available switched power sources. So, I combined the new gauge +12v with the cigar lighter onto one spade connector. The Oil Temp reads about 85 degrees Celsius (185 degrees Fahrenheit) at full operating temperature and I'm seeing 13 Volts at idle.

Second, with the extensive help of the GA Opelers, I replaced my exhaust manifold with the "Sprint" design and also replaced my intake manifold with one modified to accommodate the "Sprint" manifold as far as clearance is concerned. I haven't been able to drive the car enough to determine if any carb adjustments are needed. I will likely take the GT to a dyno shop in the next couple weeks too to see what I am getting at the wheels. I baselined the car at the "TN Dyno Days" when I picked the car up from Keith (opelspyder) and again earlier this year just after the CAI install. A new baseline with the "Sprint" manifold installed is on order I think.

So, back in 2007 I listed these upgrades as my "wish list":

• NOS Gas Cap and Key
• Front and Rear Sway Bars
• Cold Air Intake
• Just Dashes Dash
• Lowering Springs

The Gas Cap was completed as a gift from Keith when the car was finished which was a great surprise! The Sway Bars Keith helped me with as a "house call" after I had had the GT back for a while. The CAI I did myself using a design I borrowed from George (opelenvy). The Dash can actually be crossed off as I recently purchased a beautiful dash from Lyndon (CIARA1970) that is nearly flawless IMHO. It won't need the Just Dashes treatment - definitely show quality. I'm not sure when I'll get it installed but I have it waiting in the wings. That leaves just the Lowering Springs as an open item. However, I actually have a new list now that I've been driving the car for a couple years:

• Better Brakes
• Five-Speed Transmission
• Lowering Springs
• 105amp Alternator

Picture attachments aren't working at present so I'll try to post some photos tomorrow...

Matt

[newman27]

I can't edit my last post now, adding some pix of the new gauge install. The first picture shows the essential tools for this install: Destec diagram, FSM, and a multi-meter. Note that I wasn't able to get the new gauge to be perfectly level compared to the other two gauges. I worked on it for a while and got it close but ran out of time and had to put the instrument panel back in so I could drive the car to the Opel meet. I'll need to go back and work on that some more in the future...

Matt

[newman27]

Photos of this install are in another thread and I can't re-post those already posted. I've added a couple extras here though.

Now that I have had a chance to drive the car some, I have found that I need to check the electric choke operation, carburetor jetting, and possibly tweak the mixture / idle screws. I experienced some stalling / hesitation from a cold start. Once the car warmed up everything was great and the "seat of the pants" test still indicates some extra power out on the highway at speed. This Sprint manifold was treated with a heat shielding coating and that may be affecting the current "tune" as the under hood heat dynamics have changed.

Matt