This would be E-body, big block, and normal engine mounts, K-member.

How about the tranny mount, that looks centered to me (?), I guess.

Nope ..

Its bias to the right ABOUT 1.5 inches (pass side) on a production car for foot room

No, it's over to the pass side by about an Inch, Plays havoc with my OCD now I've cut a hole in the hood for the T/R. I don't think the trans is central either

If you move it over more it helps balance the chassis so you get more weight onto the right rear
Every stock or semi stock Mopar car I have weighed all four corners without the driver had the most weight on the left front, RF was next in weight The LR was lighter than the RF but heavier than the RR Installing batteries in the trunk helps but more weight is better on the right rear

OK, thanks guys. I'm doing a bunch of reading right now about pinion offset
and related. It seems that the "stock" Mopar pinion offset puts both the
pinion and the driveshaft in the center of the tunnel, BUT, the whole tunnel is
actually offset in the body/frame. AND the engine is offset.

This sound about right ?

Yes. I built my drag car with 1 inch offset. Or you can measure the pinion offset and use that.

A lot of the production 1960 and 1970 B body cars I've measured the crankshaft on look like they are closer to 1 3/4 to 2 1/4 inches to the passenger side
The engine and driveline torque rotate to the passenger side clockwise (looking from the front of the engine to the rear of the cars) but the engine rotation puts more pressure on the left rear tire than the right rear tire, it is trying to lift the right rear tire up instead of pushing it down Hence the driver side axle breaking sooner and more often than the passenger side. Same thing on breaking the driver side carrier caps on rear ends

Just measure the tunnel from each side, it’s not centered. Pass side Hemi cover is tight, driver side has a lot more room, measure that to tell how much engine is to the right. (All engines will be the same) Pinion is not centered either

Offset is 1” toward the passenger side.

The driveline - center of the crankshaft bolt to the center of the pinion shaft - should be straight, as far as side to side, and parallel to the chassis centerline.

The A Body stuff I've dealt with was like an 1 1/4". And I believe that number holds pretty close for the other chassis. Tolerances being what they were, that 1 1/4" could be +/- 1/8 or more. Drop stringlines and get it as close as you can.

If you're using all OE mounting, not much you can do with it. Maybe fudge the trans one way or the other.

Mopar cars are offset. The actual amount of offset depends on make, model and year. There is no one number for all cars. TTI has the best list of offsets that I've seen published on their website. I use the TTI offset guide when I design parts.

I centered my motor in my 64 Belvedere after a few "friends " badgered me into .. sounded easy but, its not .

For every action, there is a opposite and equal reaction


Sir Isaac Newton

Yeah I consulted with a race team on a Mopar they were building. They were Chevy guys and they wanted the engine in the center of the car so that is what they did. Then they had to buy two sets of floor panels to patch the floor and change the firewall and they had to modify the trans mount and the torsion bar cross member and all of that. But in the end they were happy since it looked correct to them.

How much offset would one dare go with if you haven’t started the process of engine position forward or aft or offset with a front and mid plate on a Bbody and a low deck wedge?Rearend has not been spec,d either so the slate is clean. Thanks DK I should add headers will not an issue as they will be fender well headers.

If it is a stock floor car with a stock firewall then I'd put the engine and trans in the factory location. If it is a tube chassis car then put stuff where you want it.

hings that you never even think of , get in the way .. oil filter vs lower radiator hose , I had to fight the throttle linkage cause then it hit firewall , headers where a S ob .. i had to make a slip tube on two tubes , thats just a few things , it was a pita

Here's a picture showing the offset to get the shaker in the middle of the hood on a my Hemi Cuda .Engine almost hits on right side. This is factory location. The steering column wouldn't fit if centered.

and another showing the offset of the oil pan looking at front of car.

When we did our chassis car, the driveline was put in 1" to the right. A little extra room for the driver. Desired corner weights and balance easy to achieve with minimal preload or spring manipulation from neutral. It worked well. It wasn't a big power deal. If it is i would want the stuff centered.

Stock floor, stock trans mount, stock K frame, steering, etc, I would put it in factory location. Super Stock Hemis are done that way and they work just fine. The whole engine/trans assembly can be moved back and/or down with some changes to the trans mount, if using motor plates. That would be more beneficial than spending a bunch of effort getting everything in the center. Removable/custom trans tunnel is likely needed to accomplish that. Headers on the left side with stock steering is always a challenge.

As stated factory bias is about 1.5" to the pass side. Footwell, steering box clearance is why as Ive heard both.