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Ben from what Bob said, it looks like my weak link woud be the splined part of the shaft inside the torque tube, what the rear U-Joint is attached to. All that being said, it still appears your engine may put out way more HP than the stock Opel driveline can handle, unless your real careful with the clutch. Even then full throttle application in the lower gears could be detrimental. I'd go with his recommendations wholeheartedly.
 

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boomerang opeler
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i think the order (in reverse or weakest first order :veryhappy ) is

solex carb :lmao:

spider gear

torque tube mount rubbers

pinion shaft inside torque tube

half shafts to diff joints

half shaft to axle mounts

clutch

gear box

crank to fly wheel flange

connecting rods

valve train
(last two may be reversed ! ??? )

that about right for an opel bob ?
 

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I would say that the gear box is toast before anything happens to the half shafts, and out of all of it I would think that the crank to flywheel flange junction is the strongest on the list (or the last to go.)
 

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Opeler
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359 Posts
Discussion Starter #64
Now we're starting to get somewhere

So I checked out what was holding me up at the tail of the tranny. It seems opel put in a miniature bulkhead and reduced the tranny tunnel on the underside eventhough it is still large inside the car. I'm talking about the extra sheet metal that hides the e-brake assembly so that it is not exposed to the outside. It looked as though I only needed to have the wider opening for about another 1/2 to 1 inch. So I proceeded to drop the tranny down and move everything forward so I would have room to work, but in the process the back of the tranny slipped off the jack and proceeded to dump the remaining gearlube that was in it all over the floor under the car. Since it's not much fun to lay under a car on a slimy floor I had to clean it up, which set me back atleast a half hour. After I raised the back of the car a bit more so I had some swinging room, I proceeded to adjust that pesky bulkhead. A 2.5 lb sledge and about ten minuets did the trick, but boy was my forearm tired! It took quite a while to jockey the engine back down into the hole with that transmission hanging off the back. I finally got the engine down in and the tranny tucked right up in where it is supposed to go. I shifted the engine around to where I thought it should be and put the exhaust and turbo on. It all fit!!:D Well everything but the wastegate acuator. (At this point the solution to that problem can wait) Yes that's right it is in, but there are a handful of places where there is almost no clearance. One step at a time I guess. I'm still trying to decide what angle will work out the best for the engine. Right now it's sitting pretty level but I am thinking that it may work out better for me to have it angled a little to the right like the 1.9 was. Check out the pics.

Time: 3
 

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Ben, as far as clearance goes, think about where you need the room. If it's along the crankshaft center line you won't need much, it's further away from the center line that clearance will be an issue. Let's say the top of the engine will rotate about 2 inches, and that may be a bit much depending on the rubber mounts, the closer to the crank center line it will be less. Just soemthing to think about. What is in the rear of the tranny? It sure doesn't look like a standard U-Joint yoke. That may be a problem if there is no slip or in and out movement at that point. There needs to be a method for the drive shaft to move in and out or something to take up the change in angles as the suspension works up and down. Another something to think about. :yup:
 

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Opeler
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Discussion Starter #66
What is in the rear of the tranny? It sure doesn't look like a standard U-Joint yoke. That may be a problem if there is no slip or in and out movement at that point. There needs to be a method for the drive shaft to move in and out or something to take up the change in angles as the suspension works up and down. Another something to think about. :yup:
Nissan used a two part drive shaft with a carrier bearing. There were no u-joints in the 1st segment. Instead there was a rubber coupling I am assuming it was to absorb the shock of hard starts. The shaft does however have a few inches of travel that it can slide in and out.
 

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Well, that should handle it then Ben. I was just used to seeing a standard slip yoke coming out of the rear of the tranny. You're getting there. :D
 

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Opeler
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Discussion Starter #68
I'm undecided as to whether or not I should try to use that rubber coupling. It will eat up a little power but it may help cushion the diff from sudden torque changes. The problem is space. The coupling + 2 u-joints = 0 driveshaft length.
 

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I'd have to see the setup on that coupling, maybe it's supposed to act like a u-joint kinda. If there is some radial flex it may work with just one u-joint. IDK. The other possiblilty would be to see if there is a splined standard yoke that will fit the output shaft on the tranny. Like I said, without seeing what you've got, I'm just throwing out ideas. Maybe someone on the site knows more about that tranny than I do.
 

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boomerang opeler
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ron it works on a straight line as much as it can , the prop has the same 3 legs and a boss that fits in the bearing in the centre the rubber dough nut that connects them (we call it a rotor-flex coupling ) has some angle movement but not much and relies on the centre prop bearing to deal with the axle moving , it is designed to work as a shock absorber in the prop not as a U/J
as the opel has 1 U/J at the torque tube end and the tube is mounted semi stiff ( or should be ) it should work ok ish as it will only have to deal with a small for and aft movement

for heavy use on some of my cars i have just missed out the rotor-flex and bolted the 2 tri legs direct to each other with some heavy duty rubber washers to give the movement as i have been let down by the joint a few times , it gives a clunk as the legs hit each other because the rubber has dropped out after splits form between the legs but does not fall off because of the boss and bearing
 

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Opeler
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Discussion Starter #71
as the opel has 1 U/J at the torque tube end and the tube is mounted semi stiff ( or should be ) it should work ok ish as it will only have to deal with a small for and aft movement
Baz, are you saying I could possibly use just the flex coupling and one u-joint? I'd imagine that I'd need to have the tranny and the torque tube lined up better.

Ron, here is a picture of that shaft and the rest of the flex coupling.
 

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Ben, two folks I would talk to about the dirveshaft and maybe a different rear-end, based on what RallyBob said. First, on the driveshaft, is Tim at Drive Line on Moreno Blvd. He could tell you is what you have will work with some certainty. Second is Mark at Pro-Gear in Kearney Mesa. Tim, you know, did the drive shaft on Willit? Mark, rebuilt my differentials on both the monza and GT. He also raced an Opel some years ago and is versed, I would presume, on what it would take to, either, make yours liveable or what swaps could be made with what you have. HTH.
 

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Opeler
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Discussion Starter #73
I managed to get a little time in tonight on the car. Mostly I just tinkered and did lots of thinking looking down at the engine or lying under the car. I would have pulled the engine and tranny again and continued refining my sheet metal modifications, but tonight (as with most nights) when I finally got out into the garage it was after the baby had gone to bed. This means no banging with sledgehammers and no powertools, which kind of limits what I can do. The tinkering and thinking worked out pretty well for me tonight, at least I came to a couple of conclusions on how to proceed. The good news is that I've pretty much figured out the best position for the engine; the bad news is I'm going to have to me the steering column over about 2".

You can follow along with the attached pictures. 1st I blocked the motor up so that I could disconnect the hoist. Then I slid under the car with the 1.9 cross member and bolted it up in place. It looked like the pillars lined up pretty well with were the nissan mounts are supposed to be, but the pillars are way to tall so they will have to be shortened about 4" or more. Then I removed the cross member and bolted the nissan brackets on to the motor. It was at about this point that I decided the best thing to do was to stop trying to shift to the right to get away from the steering column and just center the motor between the two frame rails. What I am looking at doing right now is shortening the 1.9 pillars down almost to the crossmember, and modifying the nissan brackets to raise the fastening surface of the motormounts about an inch or so and make it parallel to the crossmember. This will keep the nissan mounts in close enough to fit between the engine and frame rails and still fit above the crossmember.

Now about the turbo clearance on the driver's side, what to do? I'll add a couple of u-joints like Ron suggested and shift the column to the left about 2". This should give me sufficient clearance for the body of the turbo. Next I will have to move the brake light switch and tab from the right side of the brake pedal to the left side. I have to do this to give me some room for the outlet pipe of the compressor. I'm a little worried that I will have to remove the headlight cable in order to make room for the exhaust downpipe.

The other good thing that I found out tonight is that I'm going to be able to use the stock hood without modifications.(I'll even be able to use the stock hood latch mechanism!) With the hoist removed I was able to try the hood on to see if the engine held it up. It did, but less than a 1/4". I was still planning on lowering the front of the engine 1/2 -1" to get a better angle on the driveshaft anyway, so it should work out perfect.

I can't fit all the pictures on this post so I'll add a 2nd post that'll just be pics.

Time: 2
 

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Ben, I am a bit concerned about the oil filter being so close to the frame rail. You may want to double check it and see if the torque rotation would allow it to hit the rail. Also, I think the Gages (saxybiker) may have used the steering column u-joints on their V-8 GT, you may want to talk with them on that. When you get around to modifying the subframes, come on down and get my engine/tranny dolly. It's so much easier to do outside the car. :yup:
 

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You may want to look into an aftermarket remote oil filter for this if you haven't already checked into it, one less thing to clear and also would make for easier oil changes.
 

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Opeler
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Discussion Starter #77
You may want to look into an aftermarket remote oil filter for this if you haven't already checked into it, one less thing to clear and also would make for easier oil changes.
You read my mind! I'm not worried about it hitting anything when the engine twists but in the current location I would probably have to remove the motor mounts and crossmember every time I wanted to change the oil.

Ron, I'll take you up on that dolly. I'll probably need get the engine height set while it is in the car and then measure down to the crossmember so when I do the setup outside of the car I get it in the right position up and down.

Another advantage I just thought of to moving the steering column over is it will give me more room for the gas pedal and cable. I'll be using the nissan 240sx gas pedal. I also have the clutch pedal assembly but I don't think I will use it because it is too bulky.

Friday night I ordered a new 2.25" core aluminum radiator which should be here by the end of the week. Maybe I'm getting ahead of myself but it'll be here if I need it for to check fitment.
 

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Ron, I'll take you up on that dolly. I'll probably need get the engine height set while it is in the car and then measure down to the crossmember so when I do the setup outside of the car I get it in the right position up and down.
Sounds good Ben, I sent you a PM.
 

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Opeler
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Discussion Starter #79
I didn't get too much done tonight. I put the front bumper on so don't snag my pants on the brackets anymore while walking around the car. (they've caused gaping holes in two pairs so far) [and] I did some work on the gear shifter. I am putting together some simple linkage to translate the motion of the gearshifter about nine inches forward. I will have a stub shifter coming out of the transmission back by the e-brake conected to the original GT shifter in the shifter hole. The way I've drawn it up it is very easy to assemble and shouldn't have much additional slop, but we'll have to see how it turns out. I'll post pictures once I get it assembled the rest of the way.

Time: 1
 

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Opeler
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Discussion Starter #80
Another day, a little more progress. I pulled the engine and tranny yet again. This is starting to be a twice a week activity. A trimmed the openings in the foot wells just a tad and folded the long vertical edges over to make a nice rounded edge that won't cut me while I'm working. I also made a little more room for the tail of the transmission. I attempted to change the clocking of the compressor housing to the turbine housing to get the compressor outlet in a little more desirable location but to no avail. One of the clamping bolts refused to budge and now has rounded corners. I was thinking that if I can get an exhaust manifold the tucks the turbo in a little tighter to the motor and a little bit farther forward then I may not have to move the steering column and I would have more room for the exhaust down pipe. I wonder if the manifold used on the Bluebird is any different from the one I have.

Time: 3
 
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