Most modern cars have the motors and transmissions offset. Some are moved a few inches to one side. My Dakota pickup has the motor off set towards the passenger side 3" off center, and its done pretty well for over 200,000 miles. How many of those much loved Ford 9" rear axles are factory offset? Ford offset the rear axles because the motor & trans were offset.
Ak Miller was prone to engine offsets. The 406 and 427 in his Pikes Peak Devin were both offset, mainly to give him foot room. He was known to feign shock when people would point out the offset, close the hood, and say he was going home to fix it.....
Wait, what,,,,lol. I'm just a simple country boy. It's like explaining brain surgery to me. I'm hoping me and my tape measure can get it close enough. Thanks though!
I'm sure you will be fine. Just treat any engine/trans offset the same as you would the side view pinion angles. Keep both uni angles under 3 degrees and within 1 degree of each other in both the vertical and horizontal views and it will be ok. Trust me, if you get it wrong it will send you vibration messages to let you know........
OK, I have the Nailhead all bolted in the 53 Studebaker. It is almost centered, only about an 1/4" difference when measuring from the frame to the crank pulleys. A buddy gave me a pair of steel engine mounts for a SBC/vintage Ford swap. I had to slot one top hole just a little and then was able to bolt it to the Buick engine. For now, I just have the 2 top bolts in, but when I pull the engine, I will modify the mounts to use all 4 block tabs. Then used 57 Chevy rubber donut mounts, redrilled the stock Stude frame pad and bolted it right in. I made a custom transmission cross piece, using a stock Buick SP 400 trans mount. I was even able to use the other stock Stude cross piece that went under the bell housing area. Had to trim it a bit to clear the flywheel cover, but the engine/transmission is now all bolted in (temporary of course). I think that deserves a cold beer!
1/4" sideways offset is not even a blip on the radar. On a 4' driveshaft it will only change the uni operating angle by around 0.3 degrees.
If you have 1/4" difference from each frame rail to the pulley you actually have only 1/8" offset relative to the centre line.
I have seen engines in hot rods shifted an inch or so. Some big block MOPARs are offset as much as 1 1/4. Like @alchemy said move everything and keep it parallel to the chassis centerline. You'll be fine.
My engine is centered, but the offset at the pinion is almost 3" from center. It's got thousands of miles on it now both highway and city with no vibration or U joint issues. Offset is nothing to worry about; but angles cancelling each other is. Moving sideways with offset always cancels each other, so just need to make sure the two ends of the driveline cancel each other vertically.
Roughly the same here. If the axle is perpendicular to the chassis centerline, and the engine and transmission are parallel to it, it is all good, within reason, or course. It would be difficult to offset and engine and transmission on the horizontal plane, such that it would be a problem with the u-joints.
A whole lot of vans have a big offset, too. With those, often the driver's feet are not next to the transmission or bellhousing, but actually next to the engine itself. That is a much wider obstacle to deal with.
Willys Jeeps had quite an offset for driveline clearance, and the rear driveshaft was still angled to one side to meet the rear end. A military Humvee powertrain is mounted at a slight angle towards the passenger side, with the output yoke on the centerline with the rear diff, I never noticed until I bought one. Even the fan shroud is made at the same angle to mate to the cooling package which is square with the frame. I haven't measured it, but it looks like about 5°. No way I could ever let myself build something like that!
Highly offset differentials exist in OEM, 4x4 and hot rod versions. So long as you are within the operational limitations of the components, the only other limit is imagination.
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