I stuck a T-brake in my T400 just in case I get the urge to try top bulb cause I suck at leaving off the bottom. I've got 1310 joints in both ends, 1 solid and 1 with a zerk, I don't know why. I've thought about changing to a 1350 in the front at the very least. I normally run 1.32-1.34 60's but have been 1.288 torqued up foot braking. I'm worried about a neutral start type leave with a t-brake. A well respected racer told me the 1350's won't do much, if anything, because the drive force is still fluid. He advised that the change would be necessary if the car had a clutch in it. Have you raced a 6.0X, 3,000 lb car with a brake and small u joints without issues?

why risk the potential costly damage? Change the joints to solid 1350s

Ron,with a trans-brake you definitely should use 1350 solid joints.I broke 1330's in my 1800lb. altered and it was ugly.

quote:

Originally posted by Ron Gusack:
I stuck a T-brake in my T400 just in case I get the urge to try top bulb cause I suck at leaving off the bottom. I've got 1310 joints in both ends, 1 solid and 1 with a zerk, I don't know why. I've thought about changing to a 1350 in the front at the very least. I normally run 1.32-1.34 60's but have been 1.288 torqued up foot braking. I'm worried about a neutral start type leave with a t-brake. A well respected racer told me the 1350's won't do much, if anything, because the drive force is still fluid. He advised that the change would be necessary if the car had a clutch in it. Have you raced a 6.0X, 3,000 lb car with a brake and small u joints without issues?

A clutch is not instant on either nor does it provide torque multiplication like a converter does! So IMO he is dead wrong about his clutch vs converter example. Now whether or not you need the larger joint is another story. In general every part in the drive train will eventually fatigue and fail. The front joint will see more impact loading than the rear joint so it will go faster. The joint with the grease fitting, depending on how it was installed could weaken it more than if install correctly. Also the small diameter hole in the middle of the joint to allow grease to flow to the needles has little impact on the strength of the joint. The diameter of the joint and the length from cap tp cap is where the real added strength comes from.

In your case, the joint may be only one of the week links, what about the rear trans yoke and driveshaft!? Even regularly changing the u joints won't address the yoke and driveshaft. Either way, make sure you have a good drive loop, front and rear.

quote:

Originally posted by Ron Gusack:
I stuck a T-brake in my T400 just in case I get the urge to try top bulb cause I suck at leaving off the bottom. I've got 1310 joints in both ends, 1 solid and 1 with a zerk, I don't know why. I've thought about changing to a 1350 in the front at the very least. I normally run 1.32-1.34 60's but have been 1.288 torqued up foot braking. I'm worried about a neutral start type leave with a t-brake. A well respected racer told me the 1350's won't do much, if anything, because the drive force is still fluid. He advised that the change would be necessary if the car had a clutch in it. Have you raced a 6.0X, 3,000 lb car with a brake and small u joints without issues?

We have two cars using 1310 solid u-joint for too many years (using trans-brake). One car weighs 2900 the other 3050, with drivers. They both 60' in mid 1.30 range, but we generally race them in the 1.41 60' range. We have never broken a u-joint in either car. The heavy car gets a lot of runs put on it & u-joints are replaced every 2-3 years in both. Someday, I'll upgrade.

We broke several of the smaller u-joints on our 3200 lb car.

Built a new driveline, changed the yokes for heavy duty 1350 series and never had another u-joint problem.

If you decide to keep your smaller u-joints, do yourself a favor and install a rear driveline loop. The track owner and other racers will really appreciate it so that you don't chew up the starting line when it breaks.

Do you bolt in the rear loop just in front of the ladder bar mounts? Looks pretty far forward but if it was back nearer to the rear the driveshaft would hit it when jacking up the car to take the slicks off.

No matter what joint you use overtightening the U bolts on the rear joint can be a problem. You can google the spec but I believe it's 35 ft.lbs. I saw enough people do a lot of damage to their cars by breaking a driveshaft and or U-joints that I bought a new shaft with 1350 joints and used an MW trans yoke and a billet diff. yoke. My cars not fast but I didn't want to take a chance. I was using an antique factory driveshaft that was shortened with factory yokes and a 1310/1330 joint I the rear.

quote:

Originally posted by Eman:
No matter what joint you use overtightening the U bolts on the rear joint can be a problem. You can google the spec but I believe it's 35 ft.lbs. I saw enough people do a lot of damage to their cars by breaking a driveshaft and or U-joints that I bought a new shaft with 1350 joints and used an MW trans yoke and a billet diff. yoke. My cars not fast but I didn't want to take a chance. I was using an antique factory driveshaft that was shortened with factory yokes and a 1310/1330 joint I the rear.

This car isn't fast either and it's had the factory shaft it came with in 1970. I over tighten the u bolts on the rear joint. Did you get the shaft from MW? Did you put a driveshaft loop in the rear?

you're on borrowed time. But a new driveshaft and if the budget allows, buy it from Mark Williams.

quote:

I over tighten the u bolts on the rear joint

M/W lists the U-Bolt nut torque setting at 18 ft lbs. Read last sentence of the Drive Shafts paragraph.
https://www.markwilliams.com/d...ine-maintenance.html

This is from Spicer
http://www.plazafleetparts.com...taching_hardware.pdf

Glad someone linked the torque specs, I can't remember anything and have to look stuff up every time!
I bought a Strange driveshaft through Summit, great price and free shipping. I found the MW yoke used, it's overkill for my car but I'll never have to buy another. The pinion yoke I bought with my ring and pinion from Quick Performance. My rear crossmember is under the shaft but there isn't a complete loop.

If it wasn't already mentioned, use Spicer ujoints as well. My car used to have 6 ujoints and the Spicers were the only ujoints that would last in my 1/2 shafts and my car isn't that fast. I've since put a solid rearend in the car and also changed my main shaft & yokes to 1350 joints a couple of years ago after breaking a 1330 (Lakewood). One less thing I have to worry about now.

quote:

Originally posted by 1320racer:
why risk the potential costly damage? Change the joints to solid 1350s

I would recommend this as well. If you break a driveshaft, almost certainly you will damage the trans also.

Quick story of incredible luck.....

In March of 2015 I bought a turnkey race car after being completely out of racing for 30 years. The engine needed rebuilt, but was still running with good oil pressure, so I made two passes in it in the 8.75 @ 154mph range before pulling the motor. I stuck a fresh 482 in it and had a lot of fun running 9.50's over the next two years. 277 passes in two years with that little engine with low 1.27 sixty ft. times. Got ready to put a much stronger engine in it, and thought I would put new u-joints in it, just to be safe.

All those passes, plus the 75 runs the original owner put on the car were done with cast, asymmetrical 1250 series Neapco u-joints!

New 1350 shaft and rear end yoke were quickly installed.

1320 is telling it like it is. You probably do not have to go alumnium BUT Mark Williams steel with the 4130 weld yokes and 1350 solid u joint is the way to go. There are also others Strange,Drive Shaft Specialties,etc. Out the door ballanced ready to put in $540.00-575.00.Im not trying to spend your money. If you ever see the inside of a race car after a drive shaft failure it will scare the bjeeeeess out.

Thanks for all the replies. I'll be looking at MW and Strange 3"chrome moly. I gotta put a 1350 pinion yoke in it before I can figure length. I still have to put the engine and trans back in too.

quote:

Originally posted by Ron Gusack:
Thanks for all the replies. I'll be looking at MW and Strange 3"chrome moly. I gotta put a 1350 pinion yoke in it before I can figure length. I still have to put the engine and trans back in too.

Ron,

Watch the critical speed using a 3" diameter and long driveshaft. MW and others have a some good critical speed charts.

https://www.markwilliams.com/servicebull/sb0049.pdf

Jason G.

there is no way I would make 1 more pass in that car with a stock driveshaft from 1970 in it.I had a stock driveshaft explode in the lights30 years ago. I was only running mid 11's then and I got lucky I didn't lose my right arm,a piece of my driveshaft was hanging out of my headliner. It was like a bomb went off. Nothing but quality driveshafts and 1350 joints for me after that. like Ed said if a mw shaft isn't in the budget there are several respectable builders out there.

I forgot to add it also broke my bellhousing on my t400.

quote:

Originally posted by Tim Mitchell:
there is no way I would make 1 more pass in that car with a stock driveshaft from 1970 in it.I had a stock driveshaft explode in the lights30 years ago. I was only running mid 11's then and I got lucky I didn't lose my right arm,a piece of my driveshaft was hanging out of my headliner. It was like a bomb went off. Nothing but quality driveshafts and 1350 joints for me after that. like Ed said if a mw shaft isn't in the budget there are several respectable builders out there.

I was looking at the critical speed factor a few days ago. I'd never heard of that before visiting the MW site. I guess I've been extremely lucky with this shaft. It's been some low 9.50's in the 1/4 mile days of the past. I've only had one driveshaft break and that was driving for someone back in the 70's. A piece came through the floor and brushed my right arm as it went by. Happened right off the starting line in a clutch car.