rear driveshaft length and diameter

[junior]

I have removed the stock champ rearend in my 54 coupe, and replaced it with an S-series Blazer rear end. The pinion angle has been set, and I have corrected the geometry woes I had with the front driveshaft and SBC/turbo 350 trans. I now need advice for getting the rear driveshaft length and diameter of tubing set.

1. how far should the slip yoke be inserted into the front driveshaft when the car/rearend is sitting at ride height? I need to know this so I can determine the rear driveshaft length before I head off to the driveshaft shop.

2. can I use the champ rear driveshaft and just have it shortened? Is the champ tubing diameter/wall thickness the same as the commander? I can't tell from the parts manual because it only states a length difference between the 6cyl and 8cyl shafts. Is the champ shaft up to the task of handling the power from a mild 283 Chev?

Thanks for any help you can provide. This swap is taking up alot more time and energy than I imagined...I hope its all worth it in the end just so I run run the offset of wheels I have chosen...now I understand what my dad meant years ago when he would come in from the garage mumbling something about he should have just left the six in the car...by hey it was 1960's...like father like son. One day we might both learn. Thanks, Junior

54 Champ C5 Hamilton car. Stock...no way! A Stude hotrod since 1960. In my family since 1958.

[nibbs53]

Hi Junior.
Hope this will help.

http://www.musclemotorparts.com/driveshaft_measure.htm

nibbs53 (Patrick)

[StudeRich]

That's great for a one piece shaft, but you have to wonder if you could translate that to a two piece one like Junior is trying to build or not! [:0]

A Center support Bearing is nothing like a Trans. tail-housing.

StudeRich

[nibbs53]

Two piece drive shaft set up.

Angle setup for two-piece shafts is similar to the one-piece. All three working angles should add up to zero. The easiest way to do this is to mount the front shaft section so it has zero degrees through the joint at the transmission. The rear shaft may then be treated as if it were a single shaft. Sometimes this is not possible and all three angles must be juggled to arrive at zero. It is a good idea to allow for some up and down adjustment at the center support mount so the angles may be tuned as necessary once the car is driven. Vehicles that do not have the proper angles set in the driveline components will experience pulsations that will cause vibration in seats, mirrors, gearshift levers, and other miscellaneous parts. These pulsations can also destroy transmission clutch packs, tailshaft housings, rearend bearings, gear sets, and axles. Another concern in this area is a compound angle that comes about if the centerline of the differential is not in direct line with the centerline of the engine and transmission. Luckily most rodders are visual conscious when setting up the rearend and use housings with the pumpkin centered perfectly in the center of the vehicle. Pay equal attention to avoid any compound angles while setting up the engine/trans relationship to the rearend. Setting up the components right from the beginning can save a lot of frustration and costly repairs down the road.

[junior]

Thank you for your input...the front driveshaft geometry has now been corrected, and is aligned with the crankshaft/tailshaft, so I think I will treat the rear shaft as the only driveshaft.

I still need to know if the Champ driveshaft tubing is the same diameter/wall thickness as the Commander driveshaft. Who can provide an answer to this question? Thanks again, Junior

54 Champ C5 Hamilton car. Stock...no way! A Stude hotrod since 1960. In my family since 1958.