Driveshaft OD/what you using

[69 GTX]

So I've started researching driveshafts for my car. .78 OD with 28" tires with 3.73 gear.
Shaft will be about 36" long from joint to joint (gearvendor OD)
I've read the bigger the OD the higher the critical RPM
I did the formula at 6Krpm with my set up so top est. speed would be about 175 with 3.73 & 150 with 4.10
I plan on racing it some, 590 hp 440 auto foot brake. Street/strip dot slicks.
I can't seem to find any hp recommendations for the different types.
I'd just like some ideas before I call Mark Williams to have one made. I'm probably a couple months from ordering as I need to get the car farther along and set the pinion angle ride height ect.
Thanks

 

[threewood]

Tim, this is where I bought mine. They have a chart somewhere that shows lengths and thicknesses needed for different RPMs and H.P. outputs. I am super happy with mine. I called and talked with them before buying.
http://www.driveshaftspecialist.com/

 

[Yatzee]

I believe that more of concern for you would be the strength of the U-joints regardless of the shaft, weather it be 3, 3 1/2 or 4 OD. Your shaft is not very long so the chances of it twisting are very low. I run a 3 1/2 (3/16 wall) that's 51 inches long behind 630 HP with 3.23's pushing 4700 lb's of car with no issue. Contact the above link and ask away.

 

[69 GTX]

I was thinking the 1350 u joints.

 

[Budnicks]

I've done 3"-3.5"-4" in alum with 7290 1.125" x 3.625" & 1350 U-joints
these guys treated me well the last couple times
http://www.dynotechengineering.com/

I have had a couple 3" moly shafts for street cars {Strange Eng. IIRC}

My altered had a solid 1.825" splined shaft with slip collars, Lenco IIRC

I use to use Driveline Specialty Services a lot out of Concord Ca.
until I moved

I was thinking about going QA1 Carbon Fiber DS
on my current project, don't think for anything over 500 rwhp
I'd go anything less than 3.5" Alum. Not sure on the carbon stuff, not sure the size yet
go to their site www.qa1.net
somewhere catalog/motorsports pdf page 10-11-12 ish , IIRC
a good right up, explanation

But;
I've never broke a drive shaft {knock on wood},
I have broken a few yokes & a few U-joints even the 1350's

 

[cudatom]

In my wagon I purchased the drive shaft from Dr Diff. It is a Strange piece. I wnd w/3" and 1350 ujoints. I dont think a 3.5 would have cleared.

My Cuda I ran a stock 340 shaft w/a combo rear joint. This was behind my big block and went low 10 teens. I know it was a bomb waiting to happen but that what most of us ran 15 yrs ago.

 

[malex]

I run an aluminum 3.5" driveshaft with 1350 U-joints.

 

[silver67]

3-1/2" steel
1350 front and rear
Local shop in central NY

 

[gtxracer]

3-1/2" steel
1350 front and rear
Local shop in central NY

The exact driveshaft in my GTX built by "Driveline Engineering" here in the Northwest.

 

[silver67]

The exact driveshaft in my GTX built by "Driveline Engineering" here in the Northwest.

Little just to be safe

 

[HEMI-ITIS]

I'm lucky to have s friend with a Driveshaft shop{cheap plug} http://www.supershafts.com/ Make me anther shaft,this time it's a 4 inch aluminum shaft.He said it would handle whatever I threw at it! At 3700 lbs and any decent amount of power you have to have the right one.I broke a rear u-joint coming out of the gate many moons ago..........

 

[malex]

I'm lucky to have s friend with a Driveshaft shop{cheap plug} http://www.supershafts.com/ Make me anther shaft,this time it's a 4 inch aluminum shaft.He said it would handle whatever I threw at it! At 3700 lbs and any decent amount of power you have to have the right one.I broke a rear u-joint coming out of the gate many moons ago..........

View attachment 571693 View attachment 571694 View attachment 571695 View attachment 571696 View attachment 571697 View attachment 571698 View attachment 571699 View attachment 571700 View attachment 571701 View attachment 571702

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Wondering what brand of 1350 u-joint did you use?

 

[451Mopar]

I used the Mark Williams 3.5" Chromoly driveshaft with 1350 U-Joints when I put the Strange S60 into the Charger.

 

[malex]

I used the Mark Williams 3.5" Chromoly driveshaft with 1350 U-Joints when I put the Strange S60 into the Charger.

View attachment 571782

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Is there better grades of 1350 u joints out there? If there is, what's best?

 

[biomedtechguy]

I have a vibration that I'm sure is the driveshaft. Originally it was because of a 8 3/4 shaft in a Dana 60 car. Brought it to a good local shop I've used as have many whom I know they altered it and it got better. I may go ahead and get my "forever" driveshaft now with my future 6xx HP AND TQ stroker motor in mind. I now have a 4.10 and a Passon a855 5-speed vs my a833 and 3.54s. I know my driveshaft is spinning faster now so I may as well go for it now.
Thanks for the replies and to the OP for the post.

 

[biomedtechguy]

Yep, 2/2018 and only now am I ready to buy that driveshaft.
I'm glad I put the deposit on the BME block or I'd be on my death bed posting about my plans for it...
FastShafts gave me a price on a chromoly steel 3½" diameter shaft with 1350 U-joints for $700 including the manual transmission slip yoke, and $165 for a new 1350 yoke for the Dana 60.
Comments? Opinions?

 

[malex]

Yep, 2/2018 and only now am I ready to buy that driveshaft.
I'm glad I put the deposit on the BME block or I'd be on my death bed posting about my plans for it...
FastShafts gave me a price on a chromoly steel 3½" diameter shaft with 1350 U-joints for $700 including the manual transmission slip yoke, and $165 for a new 1350 yoke for the Dana 60.
Comments? Opinions?

——
I bought the same set up from Strange 2 years ago and it was right about that same amount.

I’m curious about the block that you’ve got a deposit on. What is it?

 

[Mike Gaines]

Another very important thing....as I don't see any mention of it yet....
You gotta have a SONNAX Forged Slip Yoke. You can get it from Summit.
I also use a Strange forged pinion yoke and strap. You cant be too strong. I also use 1350 u joints...as we all know when the driveline fails it usually takes out the transmission also.
My 64 572 Hemi makes 1011HP and 805TQ so I can't afford to have any weak links in the driveline... What ever your HP and TQ if you upgrade and spend the extra money to start with for these parts you will never have to worry about them again.

 

[Fizz66Coronet]

Shaftmasters Lincoln Park MI

 

[Fran Blacker]

If your not supplying the yoke measure from end of main shaft to center of differential yoke. I measured a driveshaft I had in the car C to C of u-joints and added the length I wanted. The new yoke was thicker in front of u-joint so driveshaft was longer than I wanted, but usable.