Engine/trans angle

Kaycee

Well Known Member
Got the 700r4 in my 63 Impala and am trying to fab my own crossmember , I have the time and the material but no $$ to buy one already made. I need to know what degree angle I need to tack up it up and dry fit it to frame , my trans. pan rail says 0 degrees and my carb. surface area is reading 3 degrees slope to back of car. Does this sound about right ? The way its looking is the cross member will sit about 1/8 lower than the original mounting tabs on frame . If I stay the same height as the original mounts my trans will hit floor pan . Thanks for your time
 

61BUBBLE348

Well Known Member
Supporting Member 11
Kaycee, your angles should be measured with the car at ride height with all 4 wheels on the ground.

The angles should be measured on surfaces parallel with the crank/heads.

typically this angle is around 3 degrees up at the front, if you are underneath the car the reference surface can be the sump edge where it bolts to the block.

If you search tailshaft angles there are a number of factory charts posted.

cheers
 

Kaycee

Well Known Member
Got it on stands same height all around ,I wouldn't be able to get my fat a $$ under there if it was on the ground lol . I'll do a search and see thanks. just seems odd it is so close to floor pan . if I raise it up any I see where some after market crossmembers are adjustable. I would like to get it close so I can get the drive shaft cut and put back in.
 

61BUBBLE348

Well Known Member
Supporting Member 11
The 700R is somewhat bigger in some areas over the PG and TG.

you may need to work the seam where the firewall meets the floor.
 

models916

Well Known Member
Supporting Member 7
At ride height fully loaded, set the carb mounting surface level (0). You are going to have problems with vibration to some degree because the 700r4 is longer than the stock possibilities and will screw up the canceling numbers on the u-joints. The upper rear arm needs to be adjustable to move the pinion around. May have to shim the center bearing etc… The bigger the rear gear, the more noticeable the vibration. I gave up after a couple of years of messing around and used a one piece shaft.
 

Kaycee

Well Known Member
Am I the only one that has these kind of problems sheeesh ? Trans bolted up good only issue was the dipstick tube cut out a chunk of the seam for it to slide in . No way to set carb at 0 I would have to remove part of floor pan by the tail shaft of trans . in order to get my 0 at carb mount. I am planning on a 1 piece shaft
 

Jim Sullivan

Well Known Member
Supporting Member 10
I use the valve cover as a place to measure the engine/ transmission angle. Going from memory, I believe Grub is correct that the engine should be up in the front by about 3 degrees. The repair manual will have the angles listed for engine/ trans, front/ rear drive shaft and differential. You may have to change a little from stock with the 700 trans.
 

303Radar

Well Known Member
Supporting Member 2
You'll want the output shaft of the transmission to be similar to the input of the rear axle, especially with a one piece driveshaft. This will cut down on excessive wear on u joints. A lot of times, this is 3 degrees. Here is some useful info:
http://www.markwilliams.com/driveshafttech.aspx

However, if you have explicit control over the input of the rear axle and transmission output shaft, you can set them up for any other important consideration you have, such as the carb.
 

Kaycee

Well Known Member
Well messed with it some this pm and have 3 degrees at trans tailshaft and the rear pinion is at 1 degree
 
Try to find the centerline fron engine and trans and fit a piece of tube to one side-fit a tube to the side of the diff (make a clamp with a welded on tube/clamp to the axle housing ), adjust to axle centerline .For the check,the car should be loaded with 2/3 people and be on its wheels.Now you can see without big measurements,if both tubes seem to meet-if not do whatever it takes : make room for the trans ,or adjust the pinion angle .
In your case,I dont think you can solve the problem with adjusting the pinion angle down-I think the trans has to go up in the car to get it right. Missalignment gets you bad vibes-maybe the tailshaft housing will break under heavy load /acceleration.
Happened to a friend of mine years ago,when he put a Mercedes rear end in an El Camino....
;)
 

models916

Well Known Member
Supporting Member 7
Well, if you are going with the one piece drive shaft, center the trans output shaft in the front tunnel hole or a little to the top if needed and leave it there. Adjust pinion angle to get the alignment correct. Pinion down 1-2 degrees from the trans output shaft should do on a street car. Tunnel does have to be modified for the one piece to work.
 

64ss409

Well Known Member
Supporting Member 9
Just curious, why pinion angle down instead of parallel with crankshaft/transmission center line?
 

303Radar

Well Known Member
Supporting Member 2
Try to find the centerline fron engine and trans and fit a piece of tube to one side-fit a tube to the side of the diff (make a clamp with a welded on tube/clamp to the axle housing ), adjust to axle centerline .For the check,the car should be loaded with 2/3 people and be on its wheels.Now you can see without big measurements,if both tubes seem to meet-if not do whatever it takes : make room for the trans ,or adjust the pinion angle .
In your case,I dont think you can solve the problem with adjusting the pinion angle down-I think the trans has to go up in the car to get it right. Missalignment gets you bad vibes-maybe the tailshaft housing will break under heavy load /acceleration.
Happened to a friend of mine years ago,when he put a Mercedes rear end in an El Camino....
;)
Was the axle an Independent Rear or a Live Axle?
I'm familiar with a Jag IRS, I've put one from a '70'ish XJ12 in my '59 El Camino.
I'm curious which rear and angles your friend had misaligned. :dunno2 I'm also surprised the weak link was the transmission housing rather than the u-joints.
 
it was a axle from a Mercedes 450 SE /W116 . He broke the tailshaft under hard acceleration -said the pinion angle was not right.After further realignment,everything was holding up fine...
 

Kaycee

Well Known Member
OK fiddled with it today put car down on ground and it looks like I can make it work its sitting about 4* down on trans tail shaft . I dropped it down about 1/2" from floor board and will shim it and the rear end if needed I think the best thing I did was walk away from it for day . Thanks everyone for the HELP really appreciate it :bow:appl
 
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