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Can Opeler
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Discussion Starter #1
My “Little Project,” thread is getting too long for me to easily thumb through it for information. At this point my red GT is quickly moving on from the rebuilding stage. This thread will explore

1) The completion of my Front suspension rebuild
2) The replacement of my oil pan and diagnosis of a low oil pressure problem and a loss of oil pump prime problem.
3) the installation and tuning of a single side draft 40DCOE with MIDI kit on a 2.0L. And all the problems associated with the swap.
4)Who knows what more adventures await my GT.

Here’s how my GT looks as of now:

.



Here’s the current specs and mods:
The Car: early 1970 Opel GT with dealer installed ARA AC

Exterior: Crappy quality, but cool custom paint job, unpainted underbody, mudflaps, lots of cool stickers:)

Interior: ARA AC console with working blower, factory dash with only 2 cracks, black loop carpet with red trim. 100% factory upholstery and seats. Added AFR gauge.

The Engine: 78HP at the wheels, 98lb-ft torque in 3rd gear. 2.0L 1973 Block with 1984 XR2E 2.0L Head. Ported intake with a Weber 38DGAS running slightly rich at WOT. 3lbs lighter than stock flywheel and stock 4speed transmission with Valeo clutch. 2” exhaust with header.

The Suspension: fully rebuilt rear end with poly and 1” lowering. Front suspension is currently disassembled, but will be poly and 1” lowering.
Stock 13” wheels with redline tires (or 13” diamond racing wheels with 225-45-13 toyo proxes)













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Your interior looks really nice, Kyler. Stupid question perhaps, but what console is that? One of the few a/c consoles I've seen that I like. I don't see an a/c compressor under your hood though, so does it serve some other purpose?
 

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Can Opeler
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Discussion Starter #3
Your interior looks really nice, Kyler. Stupid question perhaps, but what console is that? One of the few a/c consoles I've seen that I like. I don't see an a/c compressor under your hood though, so does it serve some other purpose?
It is the dealer option ARA AC kit. I have the full kit, but disassembled it and put it into storage a few years ago. It was a massive HP sucker. The blower still works nicely, and some day I'll install a modern compressor, evap unit etc, to go with the beautiful console:)

New Vintage Automotive makes a full kit that is very similar to the ARA console, but I still like mine better. You should check it out Opel GT Air Conditioning kit
 

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It is the dealer option ARA AC kit. I have the full kit, but disassembled it and put it into storage a few years ago. It was a massive HP sucker. The blower still works nicely, and some day I'll install a modern compressor, evap unit etc, to go with the beautiful console:)

New Vintage Automotive makes a full kit that is very similar to the ARA console, but I still like mine better. You should check it out Opel GT Air Conditioning kit
I had the ARA kit in my 1970 GT in Arizona back in the 70s. It definitely is a power hog, and in AZ it would often overheat in city traffic even with a 3 core radiator and the 7 blade fan. But still, when it's 115 degrees out any A/C was better than none.
 

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Can Opeler
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Discussion Starter #6
I finished up my suspension rebuild today. Boy this one was not easy. I have said it before, but taking the suspension in and out of the car is NOT a one person job. I did it single handed again, but I am bruised and very sore lol.

I used similar techniques to my past 2 rebuilds on this one, but this GT suspension was by far the hardest one I’ve worked on. The metal parts have been exposed to a lot of water and dirt over the last 10k miles, maybe this caused the bolt rust problems. The bushings were pretty easy though because they have been soaked with motor oil from my leaky oil pan (which I am replacing next).

Charles Goin’s tie down straps method to relieve spring tension did work this time, but “the bolts from hell” were stuck so bad that no amount of heat or sledgehammering would free them. So I packed it up and took it to a local suspension shop that wasn’t busy. I helped out the shop owner trying to get the bolts out. It took about 20minutes of hitting them with a massive air hammer at all angles to get them to budge at all after that we cut the bolts in the middle and drove them out with press.
One thing I noticed is that the shop owner was not afraid of the spring tension at all once the spring eye bolt was removed and the tension released as far as it would with the lower arm still attached. I warned him that the Opel spring was dangerous. It turns out he was right. When it released it was not that powerful. I cautiously suggest that if the lower bolts are stuck you aren’t in significant danger from spring tension IF you already slowly removed the tension until the spring is sitting on the cradle. Still it doesn’t hurt to take precautions. Treat it like you treat a firearm. Don’t point towards yourself or others and assume it’s always loaded with tension. One plus of the lowering spring types if I ever have to rebuilt is that it can release its tension non explosively because it does t have so much camber. It can be compressed by hand.

I had a lot of trouble separating the ball joints this time. I would recommend getting the ball joint separating tools (pickle forks). The local auto store was sold out unfortunately. I damaged the threads beyond repair on one of the ball joints so I had to steal one off of my other GT. I’ll order a replacement soon.

I removed the upper bushings in less than 1 minute using a bolt to press out the sleeves and a 3/4” shank bit to grab the bushing and twist it out.

The lowers I did the same thing on 2 of them using small hole saw bit, but I had to burn out the others.

I stripped everything down to the metal and painted it with black bedliner with a gloss black top coat. I will go the bottom later with some por-15 when I paint my underbody.

As I said putting it back in was a nightmare with only one jack, but after lots of trial and error I think I found the best way to do it.
(1) unbolt the steering shaft clamp on the steering column. When you do this you can move the shaft towards the back of the car about 3in this will give you room to but it into the rack later.
(2) support the crossmember on both ends with wood block or jack stands to give you room to fit the jack under and stop it from wobbling on the rotors.
(3)lower the car until is just high enough to get under
(4)put the shock to body cups on the crossmember, you don’t bolt these on until last.
(5) put the body to crossmember bolts through the top and push on the fiber spacers.
(6)lift the crossmember and cuss at it until you can get a bolt through and put a nut on it. Tighten that bolt a bit and you can likely get the other one on that side in. Repeat on the opposite side of the member
(7)tighten the bolts all the way. The only way I’ve found to do this sigle handed is to grab the bottom but with a stubby wrench and use an electric impact wrench with several extensions up top. You can hold the wrench and the impact at the same time if you can stretch your arms like a super hero. It’s not comfortable.
(8) now that the body to crossmember bolts are tight you should be able to wiggle the body cups into place and bolt them in without too much trouble.
(9) slip in the shaft to the rack and tighten screw at the u joint and at the column.
(10) reconnect brakes, check all bolts, bleed brakes and then drive

It drives like it’s on rails and looks great with 1” lowering.

Before is bottom, after lowering is top.




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Can Opeler
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Discussion Starter #7
I got my midikit and linkage adapter in from splendid parts. It didn’t come with the filter screens it says it comes with. That makes me a little unhappy because I have to buy $50 filter screens on top of the price of something that was supposed to include them.
It will be a while before I get to installing it though. Maybe a week or two.



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Can Opeler
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Discussion Starter #9
I spent the day changing my cracked oil pan with the engine still in the car. Under the pan, a surprise was lurking.


A MAIN bearing cap bolt was not in the bearing like it should have been instead it was swimming in the oil pan leaving not only an improply secured bearing, but also the clip that supports the oil sump suction tube!

I threw out that bolt, the suction tube, and the clip and replaced them (and the pan) with ones from my spare engine.
here’s my spare engine.

I’m in awe, I know I torqued it to 72ft-lbs, and my other bolts checked out at above 72ft-lbs when I checked them today. I’m lucky there is no obvious damage yet.

It’s just one of those things! The bolt may have gotten stuck on gunk in the engine and gave an false torque reading. Maybe the bolt is bad even though it looks decent. I can’t imagine I didn’t tighten it correctly though, I was super careful since this car was my first rebuild.
There’s no way to tell, I’m just happy I busted my oil pan, otherwise I would have found out about it in a much louder and painful manner.


Changing the oil pan is one heck of a job. Drop one side of the sway bar, support the engine up top by the motor mount ears, put a jack stand under the bell housing just Incase, remove the clutch cable, and remove the 8 crossmember bolts plus the 2 motor mount nuts.
Then you drop the pan and have to lay under an oily engine to clean the gasket surface and install the new gaskets while putting sealer in the correct places. The oil pan gaskets are hard enough with the engine out of the car upside down. They are a PITA upside down.

I also installed pump gears with a .004 gap along with a new OGTS oil pump cover. The new pump and suction tube should fix my oil pressure and priming woes.
***dont forget to prime the oil pump after servicing it. Remove the square nut on the side and use a hand pump to refill the oil into it until it runs out.

After I installed my rhinolined oil pan I fired the car up and checked for leaks. It appears to be leak free at the moment!:)
 

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Can Opeler
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Discussion Starter #10
I also installed my midikit tonight.
It does not work well with the Old OGTS header. I had to do a bit of grinding on it to get it to fit.
I thought I took a picture, but it didn’t save. I showed and original and midikit manifold end to end. The midikit is roughly 1/4” larger all around.

I threaded in the “Opel tree” for the small hose on the valve cover and the brake booster.


Sorry I don’t have any good pictures yet. I’ve been very focused today with the oil pan swap and this.

It does run if you nurse the throttle. Side drafts sound pretty crazy!
 

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Can Opeler
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Discussion Starter #11

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Can Opeler
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Discussion Starter #12
Here’s some pictures of my now lowered GT in the daylight. I love the lowering look. The OGTS lowering spring is awesome. The design doesn’t bind as bad, it’s easy to release spring tension on it, and it’s much lighter so it shifts the weight distribution back more.

My GT has lowering spring all around, Koni reds that are near full stiffness up front and half at the rear, addco sway bars, poly bushings and some new joints/tierods
The steering is really tight and responsive and the car can oversteer pretty easily.

The oil pan replacement was successful. My GT has zero leaks!!! It’s finally potty trained.





 

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Can Opeler
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Discussion Starter #13
My YouTube

I made a YouTube account called "Opel Power" I have a couple of build videos up there now. They have music, nice transitions etc. I had a little fun with some of the videos, on some of them the pictures change along with the beat on the crappy copyright free music:veryhappy

Here's the build video for my red GT.
https://youtu.be/4K6buZuNzrk

Here is a video of some non build related thing like car shows and stuff. These videos are called Life with an Opel. They are much shorter than my build videos.
https://www.youtube.com/watch?v=bnzMPjiJFr4
 

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Can Opeler
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Discussion Starter #19 (Edited)
I've really been enjoying my GT lately. It runs amazing with the Midikit. It is better than the 38DGAS in every way except for one. Fuel mileage is a bit worse. I got 18MPG on this tank, but that's not horrible considering I was at WOT for at least 30 miles doing high rpm testing. I forsee this carb getting 20-22mpg average. I can improve it back to how it used to be by going down one size on the mains, but the extra fuel consumption is worth it for extra power at WOT.

Here are some pictures!
IMG_1431.jpg

IMG_1406.jpg
IMG_1404.jpg
IMG_1429.jpg
DSC_0385.jpg
IMG_1439.jpg
DSC_0387.jpg
 

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Can Opeler
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Discussion Starter #20 (Edited)
Today was a little diagnostics day. I’ve been worried about blow by recently, so I did some testing.

I only have excess crankcase pressure at idle. At higher rpms I can place a paper towel over the valve cover and it will stay. At idle there is a decent bit of pressure, but it’s not moving my hand or anything. Overall I’m no longer worried. I think my excess oil in the valve cover area is due to great oil flow in the head. My leaky distributor weep holes are annoying, but I think it must be a bad internal seal of worn bearings in the dizzy. Literally the only place my car leaks oil is the freaking distributor! I’m a little miffed. The distributor I’m using was supposed to be rebuilt by OU, but clearly wasn’t because the breaker plates were rusted solid and the vacuum advance didn’t function. Oh well. I just need to find a way to seal it. Oil isn’t getting above the breaker plates, so it’s not affecting spark, it’s just messy...

I also did a compression test. All of my numbers are within 8% of each other. The numbers are lower than I measured last year, but the numbers are proportional to last time. I’m using a different gauge this time.

Vacuum is surprisingly good considering I’m running an open manifold with a much bigger carburetor. I will note that my vacuum number are likely inaccurate as the engine wasn’t fully warm and I don’t have the recommended 1/4” port yet. It looks like an average of 17-18in HG at idle, but surprisingly more (20in-Hg) at part throttle. Do to possible inaccuracies I’m more interested in how the vacuum stayed steady without ticking, and increased/fell when quick throttle changes happened. Here’s a video. https://youtu.be/EHPvDEhF7oA


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