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I’ve got an sn95 7.5 inch open axle and an explorer 8.8 LSD with 2 inch pinion offset

Can there be any transverse misalignment from trans to diff? Or engine must be aligned...

How about split difference? Engine 1 inch over and then with a 20 inch driveshaft will be 3 degrees side angle...

Thanks

You do want to keep the misalignment to a minimum, I would think 3° is close to the limit. I have an Alfa Spyder limited slip rear in my Seven which had significant offset. I spent the money at a differential shop to have the pinion centered. New axle housings and axles. At the same time and for no extra money, I was able to set the rear track where I wanted it without have to resort to wheel spacers and such. I also had the axles built with a 4x110 bolt pattern to simplify wheel choices.. It was not super cheap at $695, but solved several problems at once.

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Parts left out cost nothing and cause no problems!!

Paul, you must have really, really wanted that Alfa rear end. Have to admit they are the best looking in any production car ever but that exceeds the Locost creedo. I have an early Celica pumpkin that I paid $20 for. Clunks a little but it was Locost!
Just hope it doesn't strand me somewhere. I had to move mine a little off center to meet the angle the driveshaft folks recommend. IIRC 3* is acceptable but no more than that.

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Larry in Seattle

leaning to the mustang, can always drop in an LSD later. Don't expect to break a 7.5 with planned power

If i used explorer and cut and centered, it might be too short at 57.75 ish inches WMS to WMS

The 8.8 is really too heavy for one of these cars IMO. I went with a 7.5 out of a Ranger. It is very easy to modify to accept Mustang rear disc brakes and you can narrow it using the same trick as the 8.8's. Once you do that, your pinion will be offset to the passenger side by all of 5/8" and the WMS-WMS measurement is perfect for a book width frame.

Yeah, by far the most expensive piece in my Seven and it is way more attractive than the Toyota lump that I ended up gifting to someone in Maine. Still though...the whole car was just over $9K, so although not the most locost of locosts, still locost. Not crazy big money, especially when you consider all of the grins we get from it. So far, 3 fillups since April 1 and it hasn't even gone anywhere useful.
So LSD vs non-LSD. As all of these cars have plenty of power to break the rear tires loose, LSD can break both rear tires loose in a corner but can exit much better...just be ready with quick hands if you overcook it. Non-LSD, spin that inside tire but no snap oversteer. Me, I am addicted to the bite and traction coming out of corner and yes, there have been a few "moments".
And as Larry says, 3° is sort of the limit.

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Parts left out cost nothing and cause no problems!!

Just curious, is 3degrees the limit for all engine-powered driveshafts or is that a limit for universal joints?

Seems I recall some vehicles at the junkyard were using CVs instead of UJs on the driveshafts and I was curious if the CVs could support more.

I offset my drivetrain and tunnel by an inch. Lines up better with my Corolla GTS live axle, more footroom since I have a narrow "book" frame. I recently put the car on a set of corner weight scales, and the cross corner totals were only 0.1 lb. different.

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book 4AGE build, Supra W58 transmission, Corolla GTS live axle

Universal joints.

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Parts left out cost nothing and cause no problems!!

Actually I am going through this right now. Now, zero angle is a bad thing, you want at least a degree or two but not more than 4-5 degrees for most setups. The maximum allowable RPM of the driveshaft will be reduced as the angle increases. My first driveshaft had about a 7 degree angle at both ends due to my bike engine being offset, and at highway speeds the vibration was noticeable. I looked for a (true) CV option but couldn't find any. CV joints that go to the wheels are only rated for the kind of RPM you see at the wheel, and are apparently not appropriate for a driveshaft application.

The next best option is a "Double Cardan" joint. Basically this is two u-joints very close together with a pilot bearing in the middle to keep everything in alignment. This gives you many of the benefits of a CV joint and basically doubles the max allowable driveshaft angle since each u-joint only sees half of that angle. The downside is that they are not available in the small sizes commonly used on these cars. I am having one custom built right now that uses a double cardan on each end, and custom made adapters to make them work with my engine output flange and reverse box input flange.

These setups are apparently pretty common in the offroading world, here's a link:: https://www.fourwheeler.com/how-to/tran ... haft-tech/

The u-joint 3 degree angle rule of thumb is not limited to either vertical or horizontal. It is the maximum in any orientation. That means that you wouldn't want to have 3 degrees vertical AND 3 degrees horizontal at the same time. Figure out the angles in both views. the formula for the total angle is (V^2 +H^2)^0.5 For instance, in the case of 3 degrees in both views the total angle is (9+9)^0.5 or 4.25 degrees. And the front angle should match as close to the rear angle as possible, ideally.

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Chuck.

“Any suspension will work if you don’t let it.” - Colin Chapman

Visit my ongoing MGB Rustoration log: over HERE

Or my Wankel powered Locost log : over HERE

And don't forget my Cushman Truckster resto Locostusa.com/forums/viewtopic.php?f=36&t=17766

My Pontiac Solstice driveshaft uses a CV at the front and a rubber Guibo at the rear

Hmmm.. I think I was given bad info from my driveshaft guy, then. Or maybe there was some other reason he thought it wouldn't work to use a high speed CV in my application, and just told me it was an RPM thing.

From some searching it appears they are also used in newer Mustangs, though I can't quite tell how they constrain the center portion of the driveshaft.

My mid 50s Alfa Giuliettas had 2 piece drive shafts. U-joint from trans to a pillow block mid length, a guibo at the input side of the rear shaft and a u-joint at the diff. Worked for them.

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Larry in Seattle

U-joints should be used in pairs.

2 U-joints? Yes.....
1 U-joint and a CV joint? No.....
2 u-joints and a guibo? Yes.

Since the U-joint has a non-linear output, it must have a 2nd U-joint to correct for that non-linearity. That is why it was OK for Larry's Alfa. I can't say what specific parts of the driveshaft design that the Zig's builder didn't like. Many(not all) CV joints are not rated for the RPM a typical driveshaft sees. Perhaps it was the right rated part availability?

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Chuck.

“Any suspension will work if you don’t let it.” - Colin Chapman

Visit my ongoing MGB Rustoration log: over HERE

Or my Wankel powered Locost log : over HERE

And don't forget my Cushman Truckster resto Locostusa.com/forums/viewtopic.php?f=36&t=17766