Setting rear end angle

[focusedontheprize]

So I am getting to the point of fabing up my Explorer 8.8 rear end in my '49. This is my first rear end fab - I was wondering what angle you set the pinion at? I was under the impression 0 is what you want to set it at under load.

I was going to put the seats and lowering blocks on, bolt everything up and put it on the ground and then rotate the rear end until I hit 0 degrees.

Just wondering if this is the correct way also.

Thanks.

[sgtusmc]

You want the drive shaft angle to zero out. If your trans output is 3 degrees up then your rear needs to be 3 degrees down. Before you set up the rear end. Do you know the trans output degree? My trans is 4 deg, so I set up the rear at 4 deg to get it to zero out.

[focusedontheprize]

Originally Posted by sgtusmc

You want the drive shaft angle to zero out. If your trans output is 3 degrees up then your rear needs to be 3 degrees down. Before you set up the rear end. Do you know the trans output degree? My trans is 4 deg, so I set up the rear at 4 deg to get it to zero out.

I am putting a NV3500 in it, so I have to fabricate the crossmember and was going to make the trans output to be 0 degrees also. I had read in a few different places of going with a 0 degree on the tail shaft.

[Kabwe]

Actually your pinion angle has to match your engine angle. Your car should be at ride height and you need a protractor. Put the protractor on your transmission tail shaft and lets say its 2 degrees down. Your pinion angle should be 2 degrees up. If its 2 degrees up your pinion angle should be 2 degrees down.

http://www.rosslertrans.com/Pinion%20angle.htm

[Kabwe]

Originally Posted by focusedontheprize

I am putting a NV3500 in it, so I have to fabricate the crossmember and was going to make the trans output to be 0 degrees also. I had read in a few different places of going with a 0 degree on the tail shaft.

You don't have to I shoot for 1-3 degrees on the engine as long as your drive shaft is zeroed out as sgtusmc said you are good to go.

[focusedontheprize]

Originally Posted by Kabwe

You don't have to I shoot for 1-3 degrees on the engine as long as your drive shaft is zeroed out as sgtusmc said you are good to go.

Ok. I am swapping in a 292, so I need to fab up the motor mounts and mounting points so my intentions were to set the motor and trans at 0 and the pinion at 0 for a 0 degree on the drive shaft.

Does that make sense?
Posted via Mobile Device

[Kabwe]

I understand what you are saying but you can set up the engine angle at almost any degree just as long as the transmission is perfectly inline with the pinion yoke. Anyway you do it I would say you need to get the car at ride height and the engine and trans mounted and start with that angle first and do the pinion last. Its easier to match the pinion angle to the engine and trans then the other way around.

[focusedontheprize]

Originally Posted by Kabwe

I understand what you are saying but you can set up the engine angle at almost any degree just as long as the transmission is perfectly inline with the pinion yoke.

Perfect. Thanks a lot Kabwe and Sgtusmc.

[sgtusmc]

Hey Bam, Does it matter how steep the angle of the tail shaft is? As long as the rear zeros? I've always shot for 1-5 degrees. So let's just say my next build is 10-15 degrees at the tail. Due to frame or cab mounts or whatever that can't be changed. As long as the rear zeros, is it cool? Like I said, I've always shot for 1-5, just curious.

[Kabwe]

Originally Posted by sgtusmc

Hey Bam, Does it matter how steep the angle of the tail shaft is? As long as the rear zeros? I've always shot for 1-5 degrees. So let's just say my next build is 10-15 degrees at the tail. Due to frame or cab mounts or whatever that can't be changed. As long as the rear zeros, is it cool? Like I said, I've always shot for 1-5, just curious.

Let's not get crazy.lol. The standard is 1-5. In theory as long as the it lines up, but lets not get crazy and put things at 20 degrees.lol I would stick with anything between 1-5 let you been doing, but in theory it should work as long as it lines up.

[skip99]

would it not be a good idea to put the pinion angle about 1-2 degrees down. below the 0 out point? I understand that this allows for pinion rotation under acceleration and eliminates vibration on hard launchs ?

[Rude Dude]

Here you go

[hammerdog57]

Originally Posted by Rude Dude

Here you go

Rude Dude, were there any images for a leaf spring setup?

[Rude Dude]

I used the middle set up on diagram I have leafs also. Just stay with in +/- 2 or 3 degree's. If you encounter any vibration at really high speeds and it is not driveshaft or u-joints you can buy degree wedges for leaf's at any 4x4 or off road Truck Part Warehouse store, I think on my 1986 C10 when I flipped the rear of the truck I paid less than twenty dollars.

ve you

Originally Posted by hammerdog57

Rude Dude, were there any images for a leaf spring setup?

[55dude]

when you install your engine you want the carb base set at level! then check the degree of transmission output shaft and if it is 3 degrees neg. the pinion needs to be set at 3 degrees pos. another myth is centering you engine in the engine bay, if you need to move it to clear something do it! if you look at a 60's mopar they are offset to clear the steering box. now if you have fuel inj. having things level isn't so critical put angles still need to match.

[Rude Dude]

I did mine different on my old model A, 1939 Chevy Coupe and my 56 Chevy pick up I never used carb but there are a hundred ways to skin a cat. I put the full Vehicle setting on ground put the degree protractor on tail shaft what every that read I put a small hydraulic bottle jack under the front of pumpkin and ajusted the rear end to opposite of what the tailshaft read. Example if it read o degress I pushed down rear to 2 to 3 degrees cause under load rear moves up. Never had a problem. I agree with the offset motors dont have to be centered look at 4x4 alot aren't centered.

Originally Posted by 55dude

when you install your engine you want the carb base set at level! then check the degree of transmission output shaft and if it is 3 degrees neg. the pinion needs to be set at 3 degrees pos. another myth is centering you engine in the engine bay, if you need to move it to clear something do it! if you look at a 60's mopar they are offset to clear the steering box. now if you have fuel inj. having things level isn't so critical put angles still need to match.

[chevyrestoguy]

Here's another twist........

What do you do when you have a 2-PIECE driveshaft? Do you still measure:
1): At the tailshaft and at the pinion

2): Or do you measure from the carrier bearing to the pinion.

On a 2-piece driveshaft, the front driveshaft is captured by the transmission and the carrier bearing and does not articulate with the suspension. Setting the driveshaft angle from scratch on a 60-72 truck with a 2-piece shaft and trailing arms is a real challenge. Under acceleration, the pinion angle reacts very differently on a coil spring suspension versus a leaf spring suspension.

I have heard multiple theories on this subject, and I would like to hear what you guys think.

[Rude Dude]

Here you go good read


http://www.rodandcustommagazine.com/...h/viewall.html

Originally Posted by chevyrestoguy

Here's another twist........

What do you do when you have a 2-PIECE driveshaft? Do you still measure:
1): At the tailshaft and at the pinion

2): Or do you measure from the carrier bearing to the pinion.

On a 2-piece driveshaft, the front driveshaft is captured by the transmission and the carrier bearing and does not articulate with the suspension. Setting the driveshaft angle from scratch on a 60-72 truck with a 2-piece shaft and trailing arms is a real challenge. Under acceleration, the pinion angle reacts very differently on a coil spring suspension versus a leaf spring suspension.

I have heard multiple theories on this subject, and I would like to hear what you guys think.

[chevyrestoguy]

Originally Posted by Rude Dude

Here you go good read


http://www.rodandcustommagazine.com/...h/viewall.html

Outstanding! That article had the exact answer to the question I've was asking. Thanks, Rude Dude, for posting that!!