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Crooked drive train

KENTON

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on my 64 Belvedere with a big block (RB) and later 727. As you can see from the pictures the end of the 727 sets off center to the left. I am putting a bracket car together for a little fun. I'm going to have a Turbo Action shifter with a later 727, but the mount must not be the one I need. Any input would be greatly appreciated.
 
I'm not sure what mount you're useing but I know there's nothing straight about a Mopar's drive train.

Engine sits crooked, tunnel is off center in the car. I'm sure some of the racers on here might have some tricks.
 
If you are sure about the location of the engine, (stock mounts?) I would just modify the trans crossmember. The later 727 mounts are not in the same place as the pushbutton trans.
On my 62 with a late trans, i just turned the trans crossmember bassackwards, and welded on the pieces of steel that i needed , to use the late trans mount that i wanted. I didn't even have to remove the factory pushbutton mount, so i can still put a pushbutton back in if i want.
Also, KK is right, everything in the drivetrain kinda wanders all over.
 
Its normal. The entire drive train is not centered from the factory. Front of the engine is off to the right. Late or early trans doesn't matter the both set on the center of the cross member. Not the best pics but this is how it sets in my 64.
Doug

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THis picture of the rear seat bottom for a 69 will show you how far off the hump is to the passenger side.
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I was studying up on driveshafts and pinion angles and it was mentioned that there is designed misalignment to get the universals to work correctly.
Having to perfect an alignment is evidently bad.
 
Pretty common knowledge that the engine/transmission duo are offset to the passenger side in our
old Mopars - and doing some quick reading up on this just now, apparently that was done for quite
a while going back a ways even before then.
They are offset but parallel to the car centerline - the engine doesn't sit "crooked" in the chassis
and once you know this, just doing some quick looking/measuring from the front of the car, it becomes
obvious.
Example: check out the underside of an A12 fiberglass hood, where the hole underneath doesn't center
up in the scoop above.
It's all done for harmonics and parts longevity and such where the driveshaft hits the rear axle, stuff I
sort of understand kinda. The angle the driveshaft approaches the diff, both horizontally and vertically,
matter - and there has to be some angle to it (can't hit directly "plumb" and square).
 
Sorry for the crappy picture, I went back and looked at it and thought I was seeing mufflers. had to do a double take, that's the floor. I want to go with the bigger U joints, 1350 I think. I hope I can center in the tunnel so the bigger yoke don't smack the floor. Sounds like I'll have to message it a little.
 
Here's a pic of my 65. The motor is offset to the passenger side, as all motors are. I use the Schumacher poly motor mounts. Also a poly trans mount. I use 1350 u-joints with no clearance problems, and a driveshaft loop.

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I'm pretty sure the only reason the motor is offset is to clear the steering box/shaft.
 
They are offset but parallel to the car centerline - the engine doesn't sit "crooked" in the chassis
and once you know this, just doing some quick looking/measuring from the front of the car, it becomes
obvious.

On my '62 with a 22" radiator, the factory radiator brackets were even made to compensate the position of the engine. The radiator leans in at the top and the right side bracket is wider than the left. There's a larger gap on the right side. The engine isn't parallel with the centerline of the car.

Installing an aftermarket aluminium radiator, I had to fab up some bushings to tilt the top of the radiator inward trying to square the fan blade with it but I didn't widen the right side like the factory did to square it in that direction. I have a little bit more fan blade sticking out of the shroud on the right side but I can live with it.

Making up my own exhaust system, I was driving myself crazy trying to make equal lenth pipes, ect. Finally I threw the tape measure back in the tool box and just cut pipe where it needed to go.

So not only is the engine a 1-1/2" off center at the radiator but it's also not square with it either. Maybe this was changed in later years with the wider bodies?
 
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And you can shim the driverside engine mount to K frame pad if needed. Like said before everyone are a bit different as far as manufacturing tolerances go. I believe Mancini and others sell shim kits. I had a 66 Charger that I had to shim the driverside,even with new mounts and tranny mount.
 
I'm pretty sure the only reason the motor is offset is to clear the steering box/shaft.
That's one of several sound engineering reasons why. Weight bias is even more important, for example - the steering box, battery, brake master/booster, etc. are all on the drivers' side, so offsetting the engine/trans works to re-establish some sort of left-right weight balance.
From what I've read, Chrysler engineers even took into account the weight of the driver!

On my '62 with a 22" radiator, the factory radiator brackets were even made to compensate the position of the engine. The radiator leans in at the top...
We're talking about the horizontal alignment of the drivetrain here; you are correct, however, in noting that the engines do tend to sit in the bay leaned back somewhat. If you remember my thread on doing my own cooling system w/Griffin radiator, the engine lean is quite a bit from top to bottom (like half an inch) BUT that vertical angle doesn't change from side to side.
The engine may be vertically at an angle, but not horizontally.

...and the right side bracket is wider than the left. There's a larger gap on the right side.
Yep, to compensate for the engine/trans being offset to passenger side a couple inches give or take.

The engine isn't parallel with the centerline of the car.
If it is not, it needs to be. Speaking horizontally, the "yoke planes" at either end of the driveshaft (rear of trans, front of diff) must be parallel but not in direct alignment.

Installing an aftermarket aluminium radiator, I had to fab up some bushings to tilt the top of the radiator inward trying to square the fan blade with it...
Yep, again trying to match the backward "lean" of the engine...

Making up my own exhaust system, I was driving myself crazy trying to make equal length pipes, ect. Finally I threw the tape measure back in the tool box and just cut pipe where it needed to go.
True dat. With the engine sitting to the passenger side a bit, no way the exhaust is exactly equal length from side to side.

So not only is the engine a 1-1/2" off center at the radiator...
Give or take, yep. 1 1/4" - 2" according to models/years.
...but it's also not square with it either. Maybe this was changed in later years with the wider bodies?
Again, it should be parallel with the body, speaking on the horizontal plane at least.

Now, all of this came in to play when I was putting mine together and I may be misremembering a detail here or there, but let me try this:
1. In the vertical plane, the driveshaft needs to approach the diff at an angle for the reasons already stated - wear of components, harmonics/vibration abatement, all that jazz.
Tilting the engine/trans is no doubt done to generate that angle and there is a factory spec on it, I just don't remember what that is. I also assume the pinion is not mounted in the diff parallel to the ground either??
The combination of the two angles gives the final desired vertical pinion angle.
2. In the horizontal plane, the yoke planes must be parallel but not in direct alignment with each other; both parallel to the car centerline itself.
Hey experts, how am I doing here? Who's got a chassis manual handy?
 
Don't overlook the differential pinion by design is offset to the right to keep axle lengths equal. I believe most manufacturer's tried to keep the differential and engine/transmission aligned in this plane, leaving the up/down plane to provide for u-joint roller action. Side benefits - slightly more room for steering gear and often the battery on the left side.
 
View attachment 839535 on my 64 Belvedere with a big block (RB) and later 727. As you can see from the pictures the end of the 727 sets off center to the left. I am putting a bracket car together for a little fun. I'm going to have a Turbo Action shifter with a later 727, but the mount must not be the one I need. Any input would be greatly appreciated.

I think you have something wrong in that picture. The engine and trans should be centered, or closer to centered than how it looks in that picture. When I build a car I slide a long pipe thru the engine and trans and point it at the pinion yoke. That way I know everything is lined up properly.
DSC_2141 (Large).JPG
 
Here this will help out even more... lol It really shows you how it centers up the rear axle when you can see the tunnel hump lined up.
centerup.jpg
 
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