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How did Ma Mopar intend for the engine / tranny combo to sit?

Mocajava

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I need a little tech help gentlemen. I installed a 6 speed TCI /GM with a Reid bell housing adapter behind my (bare)440 block and the car has the welded in tie-ins/ stiffeners to front and rear frame. The block is mated to the k member via stock engine mounts and the tranny is bolted up behind it, the entire assembly is sitting on a special dolly I built for install. I raised the car up, lowered the car over the engine/tranny combo, bolted in the k member and fabricated a new tranny cross member since the 727 cross member was useless on this GM tranny. I use my floor jack to raise and lower the rear of the dolly (pivoting off engine mounts)to get the correct angle on the whole engine assembly since I have no support under the tranny. I did use a new GM tranny mount which was bolted to the tranny and fabricated my way sideways on both sides to the frame extensions I built for support.
Here is the part I am hesitant about....As built now with tires and rims on her, the transmission pan will be level and is this correct for the way the engine SHOULD sit? When I did all the fabrication, the frame sits about 1 to 1 1/2" lower in front then the rear (I wanted a slight rake to the chassis). I leveled the tranny pan with the ground and fabricated the tranny mounts, it is just tacked together while I get input from you experts. The whole thing will be unbolted to weld up and is made to let the tranny be pulled close to how Ma Mopar designed their cars.
 
Ma Mopar ( on 64 anyway) shifted the engine to the passenger side about 2". I would guess mainly for steering gearbox clearance. The engine was tilted slightly downward at the back , which made the top of intake and the carb level. So, I believe the bottom of the tranny pan was not level ... Not positive on that................MO
 
I need a little tech help gentlemen. I installed a 6 speed TCI /GM with a Reid bell housing adapter behind my (bare)440 block and the car has the welded in tie-ins/ stiffeners to front and rear frame. The block is mated to the k member via stock engine mounts and the tranny is bolted up behind it, the entire assembly is sitting on a special dolly I built for install. I raised the car up, lowered the car over the engine/tranny combo, bolted in the k member and fabricated a new tranny cross member since the 727 cross member was useless on this GM tranny. I use my floor jack to raise and lower the rear of the dolly (pivoting off engine mounts)to get the correct angle on the whole engine assembly since I have no support under the tranny. I did use a new GM tranny mount which was bolted to the tranny and fabricated my way sideways on both sides to the frame extensions I built for support.
Here is the part I am hesitant about....As built now with tires and rims on her, the transmission pan will be level and is this correct for the way the engine SHOULD sit? When I did all the fabrication, the frame sits about 1 to 1 1/2" lower in front then the rear (I wanted a slight rake to the chassis). I leveled the tranny pan with the ground and fabricated the tranny mounts, it is just tacked together while I get input from you experts. The whole thing will be unbolted to weld up and is made to let the tranny be pulled close to how Ma Mopar designed their cars.

When all is said and done the top of the intake manifold should sit pretty much level for proper operation of the carb floats. A rearward rake of 3 to 5 degrees is acceptable but too much deviation will require adjustment to the driveline angles. I'd shoot for level in both planes at the top of the intake. Shimming can be done under the motor mount biscuits and tranny mount. Make sure the car is at your desired stance before adjustment. An angle finder is desired to do this as they're more accurate than a common bubble level.
 
Thank you both for the info and response. I have a bare block so I will confirm the tranny pan, cam and crank bore are parallel first. I dropped the tranny pan to level knowing I could always shim up to get more adjustment on the angle via lifting back of transmission. I will have to get an angle finder to determine if I am in good shape or need to modify before I weld up. Thanks again!
 
Even with a slight rake to the engine, the trans pan will be pretty close to level......
 
You may want to check out a factory service manual, in mine('68) the angle readings are different depending on body/rear axle/engine combo
 
You're car should be level measured at the rockers first. Engine and tranny should be tailshaft down 3* using a parallel surface to the crank and trans output shaft.
 
Here's a shot of my 451 and performer rpm intake. Notice that the intake accounts for the front/back engine rake to level the carb out.

IMG_4846.JPG
 
HT 413, thanks for the picture! I had to use the visual aide too,I leveled the body out using original Mopar drawings for the reference, blocking up to get the same distance from ground. Then I leveled the intake/ carb while on the engine in the body / hooked to front mounts to get that correct. Back under the car, I built a cardboard template of bottom of NEW tranny mount bushing to where the support structure will mount to frame. Now all I have to do is wait for the metal-shop fairy to turn cardboard into steel and I'm done! Maybe I should leave a couple beers in a cooler at night to help this along......
 
When installing my T56 I set the car level going off of the rockers and found the original tranny to be 3 degrees down. In the end driveshaft angles are what matters.
 
Understood, since I made a bigger tunnel AND am using a 4L80/ TCI tranny, I had no reference points to go by. Finding the schematics from Ma Mopar wasn't that easy and they didn't have any that showed a side profile for engine centerline and how it related to how the frame sits. All I had to go by was with the engine mounted at stock mounts at front and leveling the carb seat on intake and hope the tailshaft of tranny is in the right place. I had to fabricate a strong tranny mount off frame about 6" further back. I am getting very close now that I have frame at OEM height off floor, that gives me the reference point I needed. The rest is just metal work, I have 30 years experience at that and that is the easy part for me. Thanks for the help.
 
What I did to be certain was made a go-no go gauge off of a friends car. I crawled under the car and cut a piece of wood that fit perfectly between the yoke and the floor board putting the height spot on. In my case the Viper tranny took the same yoke buy for you you might have to figure in the difference. As far as left to right it sits centered in the tunnel. I also allowed for shimming up and down.
 
Building this tranny support, I am dropping it 1/2 an inch so I can shim that much DOWN. The way the mount sits, I can already go UP another 3/4 if I need to. I don't have the rims and tires I want yet and do plan on dropping the front end via the torsion bar adjustments. I like your idea of the template but I have no "other" cars to look at up here in the B body Mopar variety. Thanks for the input.
 
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