741 to 489 case swap Drive shaft and U joint question

[tommygun]

Hi All,

Just picked up a 489 3.23 sur grip center section, I read its a straight swap on my 8 3/4 , its for

my 70 charger 500,

Question is, the 489 has a large yoke, the 741 is pretty small compared to the 489, I see there are combo U joints which Ive used in the past on other cars,

Are BB drive shafts U joints larger? I'm thinking my current drive shaft is maybe off of a 318 car,

Sooo my origional setup is 383 4 speed to 741 case,

Going to 383 4 speed to 489 case,

Should I be looking for a BB drive shaft? or just use the smaller one I currently have with a combo U joint?

383s pretty mild but I will be dumping the clutch often lol

 

[rick68b5]

yes there is i have the spicer part number at home

 

[rick68b5]

just use the combo u will be fine

 

[moparcrazy]

Hello tommygun, personally I'd up grade to the larger yoke on the DS, you'll probably be fine until your tires start to bite the pavement, but if you use street drag slicks like I do, your definitely gonna need to up grade

 

[5.7 hemi]

Also your 70’ Charger did not come with a 741 center section. Somebody put that there in place of the (depending on the month your car was built) 742 or 489. But nonetheless, a combo u-joint will work just fine.

 

[66Satellite47]

If you have power you want a big quality drive shaft & big U joints. If you have big power you want a big driveshaft & 1350 U joints.

 

[wyrmrider]

you can break any of them
best to run a clutch that is not just on and off
centrifugal lock up and some lighter static is much easier on the parts as well as selection of frictions-think top fuel and funny car
something has to slip let it be the clutch and the tires not the driveshaft and axles
Don't let Sorokian die in vain
Don lost his foot for you
Leonard Harris was one of the best at feathering the old hard lock up clutch with is foot
before that it was dump the clutch and spin the tires
Purdomme's secret (Greer Black and Purdomme)
if you ever watch a Purdomme run you will see just a mere haze of tire smoke
stiff hard clutches break parts been there- done that
get a driveshaft hoop if you do not have one

 

[PurpleBeeper]

My 2-cents. You're fine using your existing driveshaft & "conversion" u-joint. Piece of cake swap. Make sure to put new sure grip additive in your gear lube & at least consider replacing the axle bearings while they're out. That center section is heavy when you're trying to line up some nuts/studs.....a transmission jack or a buddy wouldn't hurt while putting in the center section.

 

[66Satellite47]

Mopar used larger U joints in the HP cars for a reason. With a 4 speed car you want a really good driveshaft & U joints. I broke a driveshaft at 116 MPH, destroyed the 727 & tossed the shaft right over my best friends windshield. Stout driveshafts & U joints are good investment.

 

[wyrmrider]

Right
and about that driveshaft hoop

 

[tommygun]

My 2-cents. You're fine using your existing driveshaft & "conversion" u-joint. Piece of cake swap. Make sure to put new sure grip additive in your gear lube & at least consider replacing the axle bearings while they're out. That center section is heavy when you're trying to line up some nuts/studs.....a transmission jack or a buddy wouldn't hurt while putting in the center section.

From what i gather i have the cone type surgrip, that use additive as well?

 

[Don Frelier]

To answer one of your other questions, big block cars 741 cases frequently had the smaller u-joint. I have two of them.
A spicer universal joint is the best, better than a moog.
Unless you have a ton of traction you will be fine.

 

[5.7 hemi]

Yes, you will need the additive. Get the Ferd stuff, you’ll be good to go.

 

[tommygun]

Yes, you will need the additive. Get the Ferd stuff, you’ll be good to go.

FERD??? inside joke lol or is that an actual name

 

[wyrmrider]

FORD
and use only oem or genuine Dana/Spicer U joints they are the only ones that I know of that are deep case hardened- heat treated all the others are either flame "hardned" or induction/ electro surface "hardened" which wears right through and Brinnels under even moderate use
TRW used to have good U joints but they have been sold several times over since then and IDK now