Need info on degree angle of block for trans mod.

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moparmat2000

moparmat2000

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Not sure where to put this. In engine or trans, but the question is ultimately trans related. I have my car jacked, shimmed and leveled in my shop on 4 axis. I set a mock block in place and an intake manifold on it with an angle protractor. With the chassis dead level, should the carb base be level as well? I am thinking so because this sets the engine at a downward angle at the back, but I want more information. I am getting ready to mock up the trans crossmember for a 42RH. And build that while the floor is out for replacement. This would make it all much easier to do. Pix are radiator, both door sills, across the trunk floor, and the carb flange on the intake.

Thanks
Matt

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Matt, while the angle may effect the extended orbits, I don't think it will have an adverse effect on exit or re-entry. As long as it's within reason. Also, keep an eye on your mailbox for the grand prize is heading your way!
:lol:
 
Thanks Al. I never win anything, but I won this time. Thanks again. As far as the angle, can I get that one in layman's terms. BTW we took the rest of the short block apart. Crank is .020 / .020. Rod journals looked great. #2 and #4 were junk. I mean it is a "free eighteen" now I gotta get a decent crank for it.

I just wanted to know if the chassis was dead level front to back, and if the carb base is dead level, does this give me the right number of degrees down angle on the trans? I do plan on putting a degree or 2 more down angle on the trans end when I build the crossmember. This way I can shim it up if I need to.

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No, it will not be level. And should not be level unless u have ur trans/pinion angle correct. Don’t forget the rake of ur car will affect it also. It needs to be sitting on all 4 wheels with all the weight in it as a running driving vehicle. Ur way over thinking this one. Kim
 
So in that case should i pre make the crossmember piece for the trans and leave the part that holds the mount unwelded until everything goes in for the final time? Going to build my mount like this.

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Yes, and u will probably be -2 or-3 degrees down when ur done. Then ur pinion will need to be at -5 degrees or so. Kim
 
Dont want to seem hung up on this, however with my carb base level, the block is at 3° angled down. When this stuff was built new wasnt it figured around the carb being level? I got a friend who buds dirt track stock car MoPars. Starts off with square steel tube builds his chassis from that, and uses bolt on seam welded street K frames, and stock A body rear rails, and leaf springs. He works off a level surface plate to build the chassis. I can also ask him how he does it. Maybe get more insight into this matter.

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Start with getting the rear of the tranny as close to level and as high as u can. With the overdrive unit being as big as it is that may be hard to do. Kim
 
I plan on hollowing out the u shape in the torsion bar crossmember then strapping it with doubled up steel sheet with both pieces the same thickness as the crossmember. 14 gage I believe it is. Then the crossmember will be welded to the new floor pan when I put that in. Will probably be plenty strong. I plan on moving the inboard mounting holes out about 2"
 
Kim, I archived anything 42RH-46RH related in a file on my phone. These pix show me what imma gonna need to do

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Run a string in line with crank to pinion
 
furyus2 said:
The carb pad should be level. That should give about 3 * at the trans.
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With carb pad level, I have 3° angled down off my front machined surface on the block. Being that trans is machined to be exactly in line with block, then the end of the output shaft should be at 3° down as well. The only other bogey is the rear axle. Ford explorer 8.8. I will set this at -2° or essentially 2° pinion down from zero with all the weight in the car.

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need 3 degrees on motor n trans,..rear needs to be 5 to 7 degrees, when rear rotates up on the throttle you dont want to go to 0 degrees!! need to take intake off as different intakes have carb flange at different degrees, set lever across china walls and put degree finder on level to find true degrees!! all this needs to be done with suspension at ride height! its way to easy to over think all this! pulled my hair a time or 2 on this building dirt track cars!!
 
As far as the unboltable trans crossmember goes, I will build it, and not install the center part where the rubber mount goes until car is assembled and I can get a true angle. Heres pix of what I'm going to build.

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moparmat2000 said:
So as sitting with all the weight in it, the axle pinion points roughly 5° down
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5 should be fine, if ya need couple more degrees be real easy to slide a set of 2 degree shims between leafs and rear end mount later on!! then adjust pinion snubber to hit at 1 degree and your golden! nice work on that cross member!
 
Oh, I didnt build that one, but i am going to duplicate it.

Wanted to build it with a few extra degrees down built into it, so I can shim the trans up uf needed. I figure it's easier to slip shims in at the trans mount to raise it if needed.
 
I keep hearing about 3-5 degrees down on the rear axle, but when I look at my 64 sport Fury, it is clearly pointed up a few degrees.
 
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