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Can Opeler
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Discussion Starter #281
Thank you Kyler I realized when I pulled the insides out that there are little lock washers on them
I'm glad I did as 1 of the washers was split in half
I can only imagine how much damage that would cause if it fell out into the valves
Probably less than you’d think. Most likely it would just go to the bottom and eventually make it into the oil pan or get stuck on the massive amount of cast iron on the top. It would be tough for it to find a place to do damage.
 

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Can Opeler
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Discussion Starter #282
I put on some nice adjustable helm joint control arms today. They look great and seem to be quite smooth. It was a bit too cold today to do an extended test, but the car felt smooth and not much harsher than poly bushings if any.



These don’t have an e-brake cable mount on them so I put some large heat shrink and some fancy fiber tape for a temporary friction guard.

I got them from mk-rennsport. They are very high quality. Far better than anything I could have made. They have aluminum bushings and are adjustable without removing either end from the car (thank you reverse thread!)

I also replaced the bolts on my diff cover. I think that might be the last of the stock bolts on my car aside from flywheel and head bolts. Literally every other accessible nut and bolt has been replaced with a new yellow zinc plated one or plain zinc if yellow wasn’t avaliable.

My addco endlinks got bent again so I went and got some 3/8” thick ones from autozone. Much better quality and about 50% thicker.

 
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Opeler
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This is nice upgrade. Beside improved handling and increased safety, adjustable trailing arms allow perfect alignment of rear axle. I also suggest that you should install rubber boots over heim joints to protect them from water and dirt.
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Can Opeler
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Discussion Starter #284
Good idea P.J. Thanks for the link!
 

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Can Opeler
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Discussion Starter #285
I did some testing and tuning today. I’ve successfully deleted and replaced my carburetor emulsion tubes with “Venturi Fountain Tubes.” The increase in low end power is in phenomenal. It feels like I’m driving a fuel injected car. Transition is much smoother too. Without an emulsion tube transition is controlled solely by float bowl level. Right now I’m transitioning a hair later than I’d like but it’s so close I probably won’t mess with it again.

The Venturi fountain tubes and associated retuning shaved a full second off of my quarter mile time and increased my quarter mile speed by nearly 5mph. I’m at about 16.9 seconds on rough asphalt. I’d probably be able to get .2 seconds off of that at the track.

My g force meter predicted my HP based on the 2063lbs my car plus me weighed at the drag strip was 105hp. I bet that’s fairly close to correct. I’d guess 100hp is more likely. Big improvement from 78HP a few years ago.

I’m having some issues with my rev limiter kicking in intermittently at 5000+ rpm. (It’s set at 7000) I need to figure out that issue and this little car will be flying!
 

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Opeler
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1,202 Posts
I did some testing and tuning today. I’ve successfully deleted and replaced my carburetor emulsion tubes with “Venturi Fountain Tubes.” The increase in low end power is in phenomenal. It feels like I’m driving a fuel injected car. Transition is much smoother too. Without an emulsion tube transition is controlled solely by float bowl level. Right now I’m transitioning a hair later than I’d like but it’s so close I probably won’t mess with it again.

The Venturi fountain tubes and associated retuning shaved a full second off of my quarter mile time and increased my quarter mile speed by nearly 5mph. I’m at about 16.9 seconds on rough asphalt. I’d probably be able to get .2 seconds off of that at the track.

My g force meter predicted my HP based on the 2063lbs my car plus me weighed at the drag strip was 105hp. I bet that’s fairly close to correct. I’d guess 100hp is more likely. Big improvement from 78HP a few years ago.

I’m having some issues with my rev limiter kicking in intermittently at 5000+ rpm. (It’s set at 7000) I need to figure out that issue and this little car will be flying!
This is really cool to hear about. Which carb(s) are you running again? Were these something you purchased or made?
 

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Can Opeler
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Discussion Starter #287
These were designed and made by a rather inventive individual on the Weber DCOE tuners yahoo group called sidedraft central. I figure he’s still selling them but I don’t know that for sure. He also makes special idle jets for cammed cars with lower than 18inHg vacuum.
 

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Can Opeler
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Discussion Starter #288 (Edited)
Had my first autocross of the year today! Went pretty smoothly and I got first in my PAX class and 2nd in the race tire group.

Unfortunately my darn lower AC bolt sheared again. This is the second time. I upgraded to a grade 12.9 bolt to prevent it happening again, but it didn’t work.
I can’t get a broken portion of the bolt out to free the AC Compressor and I haven’t decided if it’s possible to remove the lower mount bracket with the AC compressor in place yet. I think maybe if I remove my oil filter.

I really don’t want to take this all apart and recharge the system again, but I don’t see another option yet. Sheesh

Edit: I managed to get the compressor free. Unfortunately there is a tiny crack in the housing and I’m losing pressure. Already got another compressor ordered. My friend and I are going to see about making a couple changes to how I have my compressor mounted. I’d really like a poly bushing for one of the mounts. The vibrations at 6600 must be shaking it apart even when it’s not on.

 

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Can Opeler
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Discussion Starter #290
More racing done! The Opel is kicking some butt this year. I’m first in the race tire group currently this year. My closest competition is a speedy little 110HP 1200lb Legends car. He’s usually +/- .5 seconds of me every run. I’m also racing against a 1969 spitfire, 2 69 MGBs, a LS powered Dastun 240z a 2000s NASCAR stock car and assorted miatas.

The Datsun is the only one who has beat me with raw time so far, but I still had him with PAX.

The spitfire owner redesigned his suspension with coil overs and shortened axles over the break to catch my Opel (according to his buddy). He’s getting dang close. I’ve got some work to do to stay ahead.

On the bad news side. My AC brackets suffer shear or fatigue failures at pretty much every long highway trip or autocross event. My friend and I currently redesigning a new mounting system from scratch. I’ll be sure to share what we come up with. I bought a welder the other day and repaired my current bracket and beefed it up a bit with some steel sleeves and a bit of rubber vibration dampers for the mean time.

 

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Can Opeler
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3,425 Posts
Discussion Starter #291
Back in October I got my hands on an original ZF LSD 40% locking for 3.67:1 ring gears. A guy in Texas had it and I paid a painful $800 for it. That’s still cheaper than a Quaife and the ZF is tunable and better than the Quaife for my purposes. So I bought it the moment it was posted for sale.


I called Opels unlimited the same day and purchased a 3.67:1 later style rear end with sway bar mounts. I had to pay a bit extra because it was a “real posi rear end.” (It had welded spider gears). I bought it because the ring gear looked perfect despite previously being used on one of Roger Wilson’s race cars.
After 2 months I finally got the rear end as advertised in pretty good shape.



I gave it the full knorm treatment. Sanded to bare metal, 1 coat of POR-15, black topcoat, gloss clear coat, and of course gold accents.
I swapped over all the necessary parts from my old leaky early c-clip rear.


I had a retired differential shop owner get it all adjusted for me. He only needed one crush sleeve and he got a perfect full tooth pattern for me.

It’s all installed now with a new OGTS sway bar, new brakes shoes and hardware, powder coated torque tube, and a new donut, bearing, and bumpers.


I only did a few figure 8s and a slight 2-wheel chirp today. I’ll do some more testing tomorrow.

This has been a big expensive project. I’m excited to see the results on the track!
 

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Dang very cool Kyler, Did you do the powder coating your self?
 

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Can Opeler
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Discussion Starter #295
Excellent! Are you still autocrossing this car? If so, is that what inspired the LSD swap?
Yes. Even with slicks I couldn’t put any power down while exiting corners. I just had to spin the outside tire and suffer the consequences of the car getting destabilized when wheel finally got traction again.

Also even with slicks I have trouble launching without spinning one tire significantly. And with the stock gears if I DID manage a good launch I was at a huge risk of blowing up the spider gears. This should help a lot with that.

Also I can do some more controlled drifting now on fun runs:)
 

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Can Opeler
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3,425 Posts
Discussion Starter #296
Dang very cool Kyler, Did you do the powder coating your self?
The only thing powder coated is the torque tube. I have a bunch of powder coated parts I bought from a former opeler.

The rest of the stuff is painted.
 
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Can Opeler
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Discussion Starter #297
I did more extensive testing today. It’s working great. No chatter in parking lots, and it is locking as it should on accel. It is much easier to control my oversteer now that I can put some power down to guide the car.

I only have one issue to track down. I’ve got a strange noise between 20 and 60 mph it sounds like a train on a track. It is not a metallic sound and there is no noticeable vibration from it. It doesn’t change pitch. It does increase speed with wheel speed. It doesn’t care if accelerating, coasting, or decel. It also seems much slower pulsing than the engine or driveshaft rpm.

My guess is the rear wheel bearings have a worn spot on them. I can’t hear it on jackstands though so it’s hard to diagnose.
 

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Über Genius
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9,312 Posts
I did more extensive testing today. It’s working great. No chatter in parking lots, and it is locking as it should on accel. It is much easier to control my oversteer now that I can put some power down to guide the car.

I only have one issue to track down. I’ve got a strange noise between 20 and 60 mph it sounds like a train on a track. It is not a metallic sound and there is no noticeable vibration from it. It doesn’t change pitch. It does increase speed with wheel speed. It doesn’t care if accelerating, coasting, or decel. It also seems much slower pulsing than the engine or driveshaft rpm.

My guess is the rear wheel bearings have a worn spot on them. I can’t hear it on jackstands though so it’s hard to diagnose.
Wheel bearing sounds right. With no weight on the wheel you wouldn't notice it as much.
 
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Can Opeler
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Discussion Starter #299
Wheel bearing sounds right. With no weight on the wheel you wouldn't notice it as much.
Yep that’s my conclusion as well. The bearings felt just fine. I’m about 100% sure there’s some hidden rust inside one of the bearings though.

What a pain! It’s will cost $100 just for 1 bearing and retainer. Then I have to get the old ones off and set the nip and and.

Oh well I’ll be giving Gil a call soon lol.

So much for spending extra on this being a “rebuilt” rear end lol
 

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Über Genius
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Yep that’s my conclusion as well. The bearings felt just fine. I’m about 100% sure there’s some hidden rust inside one of the bearings though.

What a pain! It’s will cost $100 just for 1 bearing and retainer. Then I have to get the old ones off and set the nip and and.

Oh well I’ll be giving Gil a call soon lol.

So much for spending extra on this being a “rebuilt” rear end lol
Why not swap in your old axles for a test first?
 
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