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Discussion Starter #1 (Edited)
I just got a call from Trans specialites. They are freshening my converter. They suggested that I convert mine to a "spragless converter". They said my sprag was worn out, replacing my sprag is actually more expensive then converting it to spragless.

Just wondering if it is benificial.
 

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ive talked to converter shops that say if its a race only car then go spragless. but im not sure on the reason or benifits..
 

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nova10sec said:
I just got a call from Trans specialites. They are freshening my converter. They suggested that I convert mine to a "spragless converter". They said my sprag is worn out, replacing my sprag is actually more expensive then converting it to spragless.

Just wondering if it is benificial.
Well they won't have to replace it again but you might want to look into what it's going to cost you ET and MPH wise if that matters to you.

Converters have a sprag for a very good reason, ask them what that is. In my opinion the only reason to go spragless is because the mfg can't build one good enough to not need frequent replacment.
 

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I just read a full page add from ATI in National Dragster about spragless converters. Stay with the sprag. Dave
 

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If you still drive it on the street, don't do it. I don't know why it would be more money, The guy that builds mine told me the opposite.
 

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The ATI ad said that the sprag costs $250-$300, so one without it should cost considerably less. Dave
 

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Anyone know how much et and mph they have lost going to spragless? We have a '68 with a new 540 and spragless TH400. The engine was dyno'd at 865hp and the best it has ran so far is 9.38 at 141mph. The car seems slower than what it should be, how much can be contibuted to the spragless converter?
Brian
 

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The ATI ad said that the sprag costs $250-$300, so one without it should cost considerably less. Dave
Gotta be careful getting your information from ads. They pay good money to post that ad, they don't do it for YOUR benefit...
 

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Here's a couple things I found:

A spragless converter is not a complete torque converter. The sprag or one-way clutch is deisgned to let the stator fins rotate with the turbine and the pump fins at higher RPM. The spragless does not rotate at all so at high RPM, those fins are in the way creating lots of heat! A real torque converter has a sprag, mechanical diode, etc.

Thank you for your questions,

Mike

Mike’s Transmission
Lancaster CA
(661) 723-0081
I just got the bolt-together converter with the clutch eliminator together this afternoon.I have run spragless in another bolt-together converter I built for someone else,but it wasn`t a direct comparison of sprag vs spragless.I could only compare it to the 9" converters he had been using.The best 60ft. in good air was 1.21.With the 9.5" spragless it was 1.18 60ft. in worse air.I beleive the mph was down 1 1/2 mph.The best ET with 9" was 5.47.It went 5.48E.T. in worse air with the 9.5".
During my sprag vs spragless test I broke a sprag and inturn cracked the stator.I`m not nocking the sprag in general just the type sprag I was using.It`s a cartridge style 22 element with 3.250 outer race.The problem is the outer race isn`t thick enuff.The 20 element with 3.440 OD or 3.250 are a better choice.I have made a 22 element with 3.440 OD race wich gives you the best of both worlds(thick outer race & thick inner race).I should have the results in 2 weeks or so.There are other things I`m testing at the same time.If anyone wants any info on what I`m doing or how I`m doing it just ask. Thanks!
 

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I have run both in a dragster. The car ran 4.80-4.85 in the 1/8 mile with a sprag converter. With a spragless from Trans Spec. the best it would run was 4.96-5.02. Mph was down 3 with the spragless. I called them and tried to get them to help me get some of the et back but they would do nothing. I will never have another spragless converter.

I realize this is not the same appliction as being discussed. Results may be different, maybe.
 

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Can anyone point me to a diagram of a transmission and a torque converter?
One other thing to note is that this tranny with the spragless converter is extremely hot after a run.
Brian
 

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I ran the Nova a couple weeks ago, still using the spragless converter. At the end of the 1/4 mile, the 280 degree trans temp gauge is pegged and begins to come down about half way down the return road. The trans is filled with B&M fluid (nonsynthetic). What should the maximum operating temperature be for the trans and/or fluid?
Brian
 

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I can tell you that I have read countless articles on this subject, including the ads in National Dragster by both ATI and Trans specialty and I have seen maybe 2 people that have said that the cars are more consistent with the spragless, but I have not read one that hasn't said the car slowed down and that the converters were generating a lot more heat with the spragless.

I personally would never run a spragless unit, but I also don't push a ton of power and am not in a fantasy world where I think that I will make a living from drag racing, so I just have fun and part of fun is going as fast as the car can. We are not in the cars long so we may as well run at peak speed and hp.
 

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Discussion Starter #15
Performance.. I lost .25 and 3mph. As soon as I changed back over, my performance returned. Before I converter, I was assurred that the only difference would be that the converter would now be all but bulletproof.

It was an expensive lesson..
 

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I know a couple guys who run T/D with spragless converters. They think they are OK but most people who are not running big motors and spraying them seem to slow down. What do people consider bullet proof? My J/W converter which I bought in 1993 was working fine in 2003 when I sent it back and paid 250 to have it loosened up/ freshened up. It was the only converter I had and it saw alot of serious use. I pro tree race with it and leave at WOT about 5900 RPMs. I also have a couple newer Greg Slack converters and they also have never failed. I tend to swap converters for different purposes but my point is if you are having excessive converter issues try a better standard converter. Coan, J/W, Greg Slack and I'm sure others make what I consider bullet proof stuff with a sprag so why fool with a spragless? I only make about 760 HP but if they don't give up why search for a better unit? I think it's like the restless leg deal on TV. Nobody knew about it til the drug companies invented a fix and advertised the heck out of it. Newest , greatest thing since sliced bread and everyone wants to jump on the wagon and get some. JMO, RM
 

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All our cars have and do run Trans Specialties converters with mech diode. Fastest converters i've tried with zero problems. You will get so many opinions on this it will make you crazy!! Too many people on the computer that aren't racers and really don't understand the concept of variables that will slow/pick a car up on different days. Good luck. I have also ran ATI stuff and had no problems either.( couldn't stand the tech guy there :beat: )
 

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Discussion Starter #18 (Edited)
Mech Diode are much tougher then the sprag, and worth the few extra bucks.. I was fastest with my Mech diode Trans Specialty converter. Purely as PM, I sent it back. I have talked to a few others whom got the same sales pitch about converting to spragless..

After that experience, I will never purchase a TS product. I now use Lupo's converters, and they have been dead on with stall speed & are very efficiency (5-6% on 5500 stall speed)..
 

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ATI Treemaster with a sprag. Read ATI's article in ND called "The Spragless Myth" shooting down TS.


Joe
 
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