drive shaft questions

[70challengerdane]

i have some desicion making to do... im putting in a 383/727/small yoke 8.75 in my challenger project out of my x-daily driver.. its a 71 4 door coronet.. now i would like to look into shortening the driveshaft before i try to buy a used one, but i do not know what the stock length is for the challenger.
so if anyone knows the length of the big block challenger driveshaft with a small yoke it would be greatly appreciated.
also if anyones in wester washington and knows of a place to have a ds shortened and balanced locally for under 100 that would be ideal!
thanks!!

 

[GranCuda70]

I Believe this data is in the Cuda challenger restoration Guide and also is located in the Fat 1970 Tech book.

Example Cuda 426 hemi 4-speed 41.75 or something ( NOT EXACT I NEED THE BOOK ) or other only a inch longer with a 8/34. I have the book lying around somewhere and can give you the numbers when I read them off. I also have a drive shaft with the BIG Yoke to fit the big Yoke on my 8/34 (489) that I will need to have shortened to fit I do not think it would cost more than 200 bucks in most shops to shorten and balance. Best thing to do is get the motor and tranny in along with the rearend and measure the distance from the center area of the open yoke ( where the u-joints go) to the tranny. I will burn that candle when I get there. I am sure there is a Jedi-Master here who can help better than I. I live in Western WA and NAMC ( NORTH American Muscle cars ) Mainly Mopar restorations Knows people that will do the shaft. Johnson Creek Blvd Portland Ore. Google them. Ask for Steve.

http://www.north-american-muscle-cars.com/contactus.html

 

[70challengerdane]

thank you! yeah ill have to get the drivetrain in and measure but yeah that gives me a good ballpark for if a shop asks how much i need it shortened... theres a guy here on febo and he has a shaft for 100 so if its a small yoke shaft i may snatch it but if not ill just get mine shortened probably

 

[GranCuda70]

book says 45.85 383 2bbl 2.76 373 ratio 3 1/4 diameter
45.60 383 4bbl ALL Ratio 3 1/4 diameter

cuda's are 43.85 383 2bbl
43.60 383 4bbl 3 1/4 diameter

42.60 Hemi .440
43.60 auto Hemi ,440

 

[70challengerdane]

book says 45.85 383 2bbl 2.76 373 ratio 3 1/4 diameter
45.60 383 4bbl ALL Ratio 3 1/4 diameter

cuda's are 43.85 383 2bbl
43.60 383 4bbl 3 1/4 diameter

42.60 Hemi .440
43.60 auto Hemi ,440

does this book include other vehicles too? basically my challenger came from the factory with a 318 904 open 8.75 small yoke and i had a daily driver 1971 coronet 2bbl 383 727 8.75 small yoke. and im putting the whole setup in the challenger... so would i want the 383 2bbl 727 challenger length?

 

[GranCuda70]

No,
only cuda's and challengers and the lengths given are for 7290 type shaft sizes ( big yoke) according to the book. 7260 type shaft sizes (small yoke) only were only installed on the 318 as with your case. I would have your pumpkin re-worked to accept the 7290 type shaft as it is stronger. If you are not modifying your k-frame, or motor mounts the 383 and 727 combo will not change your drive shaft length even if the motor is from another vehicle. Engine and power train combo's were the same, the only differences were linkage hook-ups (Auto), ehaust angles, shifter positions(manual) forward or back. The motor mounts need to be big block challenger. Small yoke will be weaker. I am not sure if the small yoke protrudes farther out from the pumkin, I had both sizes about a year ago and could have told you then but I bet they prodrude the same measurement. Call Steve at NAMC he will talk your ear off and is a really Cool guy his team knows a hell of a lot about Mopars I am sure he won't charge for info and may be able to help they have cheaper labor costs than other shops.

 

[GranCuda70]

I am not even sure if this would affect the pumpkin as I think the u-joint was the same for diff app's. I am working through this like you are and ( Padawan) and not a Jedi-master. Hope this discussion gets the gears turning. Buy a big yoke shaft it is stronger. Unless you plan on burning and wheel standing small yoke may be OK but it will prolly break.

 

[70challengerdane]

yeah my 383 is pretty tired and needs a rebuild but i dont have $400 for a rebuild right now hahaha so the small yoke is staying lol but the coronet was a 4 door and i think the wheelbase is like 2 inches longer on the coronet but when i put the motor and trans in ill measure it.. motor mounts will work as its a 71 and the k frames are the same

 

[GranCuda70]

Where you at?. I am in Vancouver,Wa. On the cuda challenger website there are a few more around SW washington.

 

[70challengerdane]

im in snohomish washington.. more acurately clearview, its about 45 minutes north of seattle

 

[AtomicWedgie]

I agree on the 7290 upgrade. I know it will be a little more money but will a piece of mind upgrade. The 7290 u joints can handle some HP also.

 

[70challengerdane]

eventually id like to but i abused the crap out of the 741 small yoke that was in before and never had a problem.. the 383 has 140k on it and it overheated a little once so its kinda wheezy. certainly due for a rebuild or at least rings but until i get a job, i gotta do the driveshaft and some brake stuff with under $200 haha cause thats all i have for now... but if any of you are interested in 1971 coronet parts i have good glass and doors and its mostly rust free. just some rust on the passenger quarter

 

[70challengerdane]

not to dig up an old thread but for an update, i had the drive shaft cut to length at my technical school (snoisle) and also am using a 489 3.55 suregrip small yoke out of a 1/2 ton pickup. rebuild the 383 kinda then had some mishaps due to snow and no antifreeze XD and am in the process of re reassembling the bolt ons and heads to a 65 steel crank block. in time the small yoke and ujoints will finally be put to the test!

 

[cv70chall]

I've got a 70 challenger I just upgraded to a 727/ 440 automatic. I have the 489 case and want the larger yoke/ 7290 setup but I need to know what length of driveshaft to search for.

Help?

 

[70challengerdane]

to quote gran cuda

book says 45.85 383 2bbl 2.76 373 ratio 3 1/4 diameter 45.60 383 4bbl ALL Ratio 3 1/4 diameter cuda's are 43.85 383 2bbl 43.60 383 4bbl 3 1/4 diameter 42.60 Hemi .440 43.60 auto Hemi ,440

formatting is weird but it's on page one does that help?

 

[moparleo]

Try this.
Woops, I see that you need 1970 drive shaft specs

 

[moparleo]

Here is a chart to measure
http://www.dennysdriveshaft.com/how_to_measure.html