Spragless torque converter

[billtroth]

I ordered a new converter to match to my new Joel's on Joy C4.  I opted for a spragless design based mainly on more durability and car is  only driven on the track.  I would be interested in any thoughts and experience on sprag versus spragless converters.

[WConley]

Bill -

A spragless converter will cost you a bit of mph in the traps.  Are you worried about breaking stuff?  The new sprags are pretty good, though for peace of mind you can specify the Sonnax "Mechanical Diode" type.  Those give you the speed advantages of a sprag converter with nearly the indestructability of a spragless setup.

JMO, of course!

- Bill

[billtroth]

Thanks for the information.  The sprag on the converter I am replacing was trashed so I am a little leary of that happening again.  Also, I race Nostalgia Super Stock which is all index racing where consistency is more important than low e.t..  I have heard that a spragless, all things being equal, will run more consistently but I'm not sure that would true or just perception.   

[jayb]

I've been told the same thing about spragless converters, they will cost you some ET but run more consistently than a converter with a sprag.  If consistency is your goal, you probably made the right choice.

[manofmerc]

One  of my fellow bracket racers bought a new convertor with this mechanical diode sprag .What is the difference between this and a standard sprag ? Just curious

[FirstEliminator]

Mechanical Diode is like a ratchet. Whereas a roller or element type sprag is like a wedge that holds a door open. 

    As a transmission rebuilder I can say I've never heard of a Spragless convertor, other than a fluid coupling. But, I'm not much into racing stuff.  I'd like to see the inside of a spragless.

[57 lima bean]

Very disappointed with the performance when I ran one.

[billtroth]

Ina spragless converter the roller sprag assembly is replaced with a solid billet .  Here's a link that explains better than I can.

https://autotransdesign.freshdesk.com/support/solutions/articles/9000098628-sprag-diode-roller-clutch-spragless-101-high-performance-torque-converter-