Coan super sprag for street, strengths/drawbacks?

Posted By: Lee446

Coan super sprag for street, strengths/drawbacks? - 03/20/11 09:08 PM

69 Satelite,528 hemi. This is mainly a street car and still uses a modified vb that retains auto function. Short story, went to a regional outlaw track for a fun run/race. Poor track prep, hooked hard on drag radials, got out about 30 ft and the tires broke loose/hooked up again and busted my sprag. In thirty years of street driving and bracket racing, this is the first time that I broke a trans and don't want to repeat it. Would upgrading to the Coan super sprag be a worthwhile investment? Are they just harder to break, or virtually unbrakeable? Do you have to do any other mods to use one? I looked on their site and read the instructions and it is basically a bolt in, I have a good torqueflite guy who builds my transmissions. I really dont know much about automatics, so any advice is welcome! Thanks, Lee.

Posted By: JohnRR

Re: Coan super sprag for street, strengths/drawbacks? - 03/20/11 09:18 PM

What exactly broke? I don't see any drawback to the super srag other than the cost. It has more rollers , they are a bit smaller in diameter , but the added amount of rollers makes it virtually impossible for the rollers to lay over which in turn allows the front drum or overspeed and EXPLODE should it reach that critical mass RPM. But making it so the rollers can not rollover will find the next potential weakness ... THE CASE .... but the Super sprag is a bolt in and I assume it's a 6 bolt like the A+A spag I just installed in a street trans I'm building. If so make sure you add the extra bolts if your trans has a 4 bolt rear support, it will require drilling holes in the case and potentially doing a little machining to the case. I spot faced where the new bolts sit and I think on a 1970 case I did I had to do some minor machining of a boss that was in the way, I counterbored it.

Short of it ... DO IT , you may or may not want to think about putting in a billet drum , the Super sprag will be extra insurance if you get a billet front drum.

Posted By: Lee446

Re: Coan super sprag for street, strengths/drawbacks? - 03/21/11 01:15 AM

Don't know yet what all broke, I took it to my trans guy friday afternoon. He says that they frequently break the case internally when the sprag goes, but I saw nothing on the outside. I don't mind spending the money for the added safety factor, just wanted to make sure what else I might need to get to do the job. Any suggestions for other improvements ? Thanks!

Posted By: dOrk !

Re: Coan super sprag for street, strengths/drawbacks? - 03/21/11 02:16 AM

OTHER than a low band apply manual VB ... there is NO WAY to get-away from the possibility of "busting" a sprag. I think that the aftermarket sprags are just another way dip-DEEP into your wallet.

I would just INSIST on better track-prep ....

..then have an uNdestructible front drum IN THERE ... like the steel one ..or the steel jacketed alum one.

Posted By: dusturbd340W5

Re: Coan super sprag for street, strengths/drawbacks? - 03/21/11 02:30 AM

well I can tell you that the Coan super sprag is using the sprag out of a ford c-6 trans and in 25 years in the business I have never seen a c-6 roll a sprag like the stock 727 do and that is because like stated above there are more rollers and there is just not enough room to roll them.
They are the only bolt in sprag that does anything for you other than save a bad case.

Posted By: dOrk !

Re: Coan super sprag for street, strengths/drawbacks? - 03/21/11 02:37 AM

.... so the Coan sprag for a TF is an exact C-6 piece ?

Posted By: JohnRR

Re: Coan super sprag for street, strengths/drawbacks? - 03/21/11 05:09 AM

Quote:

They are the only bolt in sprag that does anything for you other than save a bad case.

The A+A sprag is different than the COAN but has more rollers also , I'm not familiar with the Coan but I can't see the A+A rolling over either .

Posted By: Leigh

Re: Coan super sprag for street, strengths/drawbacks? - 03/21/11 11:17 AM

They both are 16 element.

Posted By: JohnRR

Re: Coan super sprag for street, strengths/drawbacks? - 03/21/11 02:26 PM

Quote:

They both are 16 element.

I thought one had more than the other , if not then there isn't much difference then ... I guess ?

Posted By: Scamp408

Re: Coan super sprag for street, strengths/drawbacks? - 03/21/11 10:19 PM

c6 sprag

Posted By: dusturbd340W5

Re: Coan super sprag for street, strengths/drawbacks? - 03/21/11 11:35 PM

Quote:

.... so the Coan sprag for a TF is an exact C-6 piece ?

Yes a Coan sprag come with a new inner and outer race that uses a C-6 sprag assembly.

Posted By: JohnRR

Re: Coan super sprag for street, strengths/drawbacks? - 03/22/11 03:23 AM

Quote:

Quote:

.... so the Coan sprag for a TF is an exact C-6 piece ?

Yes a Coan sprag come with a new inner and outer race that uses a C-6 sprag assembly.

I think what the protologist is asking is if the entire assembly is a C6 piece and from your answer it is NO .

Posted By: dusturbd340W5

Re: Coan super sprag for street, strengths/drawbacks? - 03/23/11 01:20 AM

Quote:

Quote:

Quote:

.... so the Coan sprag for a TF is an exact C-6 piece ?

Yes a Coan sprag come with a new inner and outer race that uses a C-6 sprag assembly.

I think what the protologist is asking is if the entire assembly is a C6 piece and from your answer it is NO .

correct only the spring and roller is a c6 inner and outer races are not.

Posted By: dOrk !

Re: Coan super sprag for street, strengths/drawbacks? - 03/23/11 03:46 AM

Quote:

protologist

U R a piece of wurk RR ... you said you blocked me months ago .. but now you follow-me-around like a little puppy-dog SMELLING around the "protologist" area ....

FIND another hobby RR ... you are BUSTED ...

.... and BTW ....the correct spelling is PROCTOLOGIST..... NUMBnutz ..

Posted By: JohnRR

Re: Coan super sprag for street, strengths/drawbacks? - 03/23/11 01:46 PM

Quote:

*** You are ignoring this user ***

Posted By: dOrk !

Re: Coan super sprag for street, strengths/drawbacks? - 03/23/11 02:57 PM

Ahhhhhh .....

... now go

to yerr PROCTOLOGIST !

Yurrr head is stuck up-there so often that surgery in-that-area must be a weekly-thing ferr you ... and this FINGER

must be a hourly occurance ...

Now where IS the flippinthebirdatRR smilie when I need-it ? ... !!

Posted By: Clanton

Re: Coan super sprag for street, strengths/drawbacks? - 10/13/11 08:44 PM

some good info here.i am needing to fix my sprag so if there are any result or info i would like to hear it.
Thanks!

Posted By: B_Body_Bob

Re: Coan super sprag for street, strengths/drawbacks? - 10/13/11 09:08 PM

Quote:

I assume it's a 6 bolt like the A+A spag I just installed in a street trans I'm building. If so make sure you add the extra bolts if your trans has a 4 bolt rear support, it will require drilling holes in the case and potentially doing a little machining to the case.

The Coan sprag in my transmission is 4 bolt.

Attached picture 6869767-IMG_3742.jpg

Posted By: lowflyingdart

Re: Coan super sprag for street, strengths/drawbacks? - 10/13/11 09:10 PM

Put in either the Coan or the A&A 16 element sprag. It will be just fine on the street. The only draw back is cost. We had a customer break a rear end with a 727 and a Coan Supersprag. The Sprag held, but was damaged. Most importantly it held and didn't overrun the drum.
Larry

Posted By: Clanton

Re: Coan super sprag for street, strengths/drawbacks? - 10/13/11 09:13 PM

thanks i just checked that out at coan.my rollers ran over most of the springs in there going from what is in my pan.

Posted By: Clanton

Re: Coan super sprag for street, strengths/drawbacks? - 10/13/11 09:16 PM

Quote:

Put in either the Coan or the A&A 16 element sprag. It will be just fine on the street. The only draw back is cost. We had a customer break a rear end with a 727 and a Coan Supersprag. The Sprag held, but was damaged. Most importantly it held and didn't overrun the drum.
Larry

mine is not for street use[heavy car3900# 1,000+ HP]

Posted By: 440Jim

Re: Coan super sprag for street, strengths/drawbacks? - 10/14/11 04:09 AM

John,
Does the A&A Ultimate Sprag use 1/4 bolts with compression ferrels?

The Coan says it uses 8mm shoulder bolts, and the case bolt holes need to be enlarge since that is slightly larger than the stock 727 5/16 bolts that thread into the case (not the sprag).

Posted By: dennismopar73

Re: Coan super sprag for street, strengths/drawbacks? - 10/14/11 04:18 AM

all these do help but if and its always a matter not if , but when it goes it will take anyones sprag!
most time the trannys junk either way,
just make sure you run a shield!

Posted By: Challenger 1

Re: Coan super sprag for street, strengths/drawbacks? - 10/14/11 12:17 PM

Quote:

I think that the aftermarket sprags are just another way dip-DEEP into your wallet.

I would just INSIST on better track-prep ....

.

Always thinking someone is trying to rip him off, it get so old...

Yea sure there gonna prep the track better because you have weak trans, yea right.

Posted By: hemi-itis

Re: Coan super sprag for street, strengths/drawbacks? - 10/14/11 02:36 PM

Doc is just bein' thrifty

There are no drawbacks for an aftermarket sprag.My builder also installs "set screws" for the stock sprag unless it's been spun.I bought the billit steel drom from http://www.tcsproducts.com/products/subcategory/14/ As previously stated,the billit steel or even the steel lined aluminum drum is a very logical up grade.I dropped my trans off to Tom yesterday,he wants to use a babbit bearing for the new converter and trim off what has to go in order to use the new CSR sheild.Insurance for the new HP levels I will be playin' with

Attached picture 6870757-2011-08-27_00006.JPG

Posted By: 10secGTX

Re: Coan super sprag for street, strengths/drawbacks? - 10/14/11 05:01 PM

Quote:

Quote:

I think that the aftermarket sprags are just another way dip-DEEP into your wallet.

I would just INSIST on better track-prep ....

.

Always thinking someone is trying to rip him off, it get so old...

Yea sure there gonna prep the track better because you have weak trans, yea right.

READ AGAIN

Short story, went to a regional outlaw track for a fun run/race. Poor track prep, hooked hard on drag radials, got out about 30 ft and the tires broke loose/hooked up again and busted my sprag

It was for FUN run not the world finals... track prep is usually 60' at your own risk.

I think the sprang and a griner V/B aka low band apply will be all the insurance you will need

Posted By: dOrk !

Re: Coan super sprag for street, strengths/drawbacks? - 10/14/11 05:12 PM

Quote:

Quote:

I think that the aftermarket sprags are just another way dip-DEEP into your wallet.

I would just INSIST on better track-prep ....

.

Always thinking someone is trying to rip him off, it get so old...

Yea sure there gonna prep the track better because you have weak trans, yea right.

ChallyNONE ... why do you keep tryin' to bust-my-stones ? ESPECIALLY when you live-in such a glass-house(being in the LPG reselling biz) ... the most complained about energy supplier in the nation ...

AND now with your MAN CARD revoked ...

Posted By: dOrk !

Re: Coan super sprag for street, strengths/drawbacks? - 10/14/11 05:18 PM

Quote:

Doc is just bein' thrifty There are no drawbacks for an aftermarket sprag.

..and the hemi-

should go on a gauge-weight DIET ! ..... ONLY reason to go to a aftermarket sprag is if your case is damaged and you can't use a OEM piece.

BUTTTT ... there IS a draw-back ...you are emptying your wallet uNnecessarly .... but if you want to spend your money IN ANY WAY you see fit ... go-ferr-it

Posted By: Challenger 1

Re: Coan super sprag for street, strengths/drawbacks? - 10/14/11 05:36 PM

Quote:

Quote:

Quote:

I think that the aftermarket sprags are just another way dip-DEEP into your wallet.

I would just INSIST on better track-prep ....

.

Always thinking someone is trying to rip him off, it get so old...

Yea sure there gonna prep the track better because you have weak trans, yea right.

ChallyNONE ... why do you keep tryin' to bust-my-stones ? ESPECIALLY when you live-in such a glass-house(being in the LPG reselling biz) ... the most complained about energy supplier in the nation ...

AND now with your MAN CARD revoked ...

Very successfully I might add for 27 years now!
What have you done sucessfully Doc?

Posted By: dOrk !

Re: Coan super sprag for street, strengths/drawbacks? - 10/14/11 05:45 PM

Yeah ... you should have had your MAN CARD revoked YEARS ago ..

What I have I done successfully ? ... ran a WORLD FAMOUS fiberglass business for years. And lately ? ... bought a few shares of Apple stock ....

And I would not BE PROUD of LPG reselling ... they are famous for ripping-people-off. LOOK UP the Michigan AG records for the largest fine ever levied and paid ....Inergy PROpain !

WHY do you INSIST on getting

and

every time you come-after me ?

You MUST like it .....

Posted By: 1968RR

Re: Coan super sprag for street, strengths/drawbacks? - 10/14/11 05:46 PM

Bottom line: your sprag is less likely to fail if it's a bolt-in. They're not that expensive and there really is no drawback in using one.

Posted By: dOrk !

Re: Coan super sprag for street, strengths/drawbacks? - 10/14/11 05:56 PM

I have done MANY 727 and 904 transmissions ...and I don't think that I have seen more than TWO trans with a spun cam.

AGAIN ...spend you $$$ as you see fit.

Posted By: 440Jim

Re: Coan super sprag for street, strengths/drawbacks? - 10/14/11 06:48 PM

Back to the topic at hand... (please)

Quote:

John,
Does the A&A Ultimate Sprag use 1/4 bolts with compression ferrels?

The Coan says it uses 8mm shoulder bolts, and the case bolt holes need to be enlarge since that is slightly larger than the stock 727 5/16 bolts that thread into the case (not the sprag).

Posted By: imfixinmopars426

Re: Coan super sprag for street, strengths/drawbacks? - 10/14/11 07:13 PM

what a bunch of babies....geez.
back to the sprag; my understanding is;
1. add a bolt in to prevent the oem from spinning in the case,or damaged case from one already spun
2.buy a "good" bolt-in if hi hp levels,[added rollers] more $$$$
3.the cheap four bolts are avalible,for home do it your selfers 80.00\
and they have ferrels to kinda take up the hole to bolt slop
4.good ones have shoulder type and added number of rollers [c-6 unit]
have CRT do the trans..

...mike

Posted By: dragram440

Re: Coan super sprag for street, strengths/drawbacks? - 10/14/11 08:18 PM

Quote:

I have done MANY 727 and 904 transmissions ...and I don't think that I have seen more than TWO trans with a spun cam.

AGAIN ...spend you $$$ as you see fit.

I had a bolt in c6 sprag in my 727 and it only lasted about 8 passes and it rolled the rollers and busted the case. Not sure why. Always did secound gear burnouts and car seemed to hook up pretty dang good.Now I have about 25 passes on the new trans and seems to be working ok.

Posted By: John_Kunkel

Re: Coan super sprag for street, strengths/drawbacks? - 10/14/11 09:00 PM

Quote:

69 Satelite,528 hemi. This is mainly a street car and still uses a modified vb that retains auto function. Short story, went to a regional outlaw track for a fun run/race. Poor track prep, hooked hard on drag radials, got out about 30 ft and the tires broke loose/hooked up again and busted my sprag.

If the VB "retains auto function" it would still apply the rear band in 1st. Were you in Drive when the sprag failed?

Posted By: Clanton

Re: Coan super sprag for street, strengths/drawbacks? - 10/14/11 10:05 PM

my sprag rolling over the springs is the only problem i have had in 20yrs and that sprag was put in in maybe 1995.i am sure it is the 12 roller so maybe it is time for the 16.

Posted By: Lee446

Re: Coan super sprag for street, strengths/drawbacks? - 10/15/11 03:57 PM

Boy, this got resurected from way back! To answer your question John, yes, it was in drive. I have a 6500 governer in it and that is why I have a auto VB in it, so I can let it do its thing. I don't want to give up the column shift, which I have never been able to get tightned up enough to feel confident manually shifting without overshooting and I don't want a MVB. With a wedge, the car was deadly consistant in drive bracket racing, and I used it that way for years with no problems. I'm beginning to think I was just real lucky!

Posted By: John_Kunkel

Re: Coan super sprag for street, strengths/drawbacks? - 10/15/11 09:00 PM

If you make a conscious decision to leave the line in Drive you risk losing the sprag...no matter who makes it.

Posted By: JohnRR

Re: Coan super sprag for street, strengths/drawbacks? - 10/16/11 01:15 AM

Quote:

Bottom line: your sprag is less likely to fail if it's a bolt-in. They're not that expensive and there really is no drawback in using one.

Only half correct , The factory type sprag with a bolt in outer race will still fail by having the rollers rollover , the Coan or A+A sprag has more rollers so it is virtually impossible to have the rollers fail.

Just replacing the outer race to a bolt in type on a trans that has not had the outer race spin in the case is a waste of time and money.

Posted By: JohnRR

Re: Coan super sprag for street, strengths/drawbacks? - 10/16/11 01:20 AM

Quote:

Back to the topic at hand... (please)

Quote:

John,
Does the A&A Ultimate Sprag use 1/4 bolts with compression ferrels?

The Coan says it uses 8mm shoulder bolts, and the case bolt holes need to be enlarge since that is slightly larger than the stock 727 5/16 bolts that thread into the case (not the sprag).

Sorry Jim I missed this question the first time around ....

Yes the A+A uses the 1/4" bolts and ferrules , I also machine the case and add the 2 extra bolts that the A+A allows you to use because it is a 6 bolt.

Posted By: Clanton

Re: Coan super sprag for street, strengths/drawbacks? - 10/16/11 02:22 AM

some good info guys,thanks!

Posted By: Leigh

Re: Coan super sprag for street, strengths/drawbacks? - 10/16/11 03:33 AM

For what it's worth, those shoulder bolts from Coan are not the best. The broach of the internal hex, is iffy, at best. The last one I used (3rd unit), I made my own spacers, out of steel tubing (like I have since 1978). MUCH better fit, and no worries about stripping the internal hex for the next builder to hassle with. Also, I personally don't see the need to add the extra 2 bolts. Any application that can sheer off 4 bolts, should have a low band apply V/B anyway.

Posted By: JohnRR

Re: Coan super sprag for street, strengths/drawbacks? - 10/16/11 05:32 PM

Leigh I just do it for piece of mind knowing it's still bolted tight if you have to pull the rear drum /gov. support , takes about 20 mins in the bridgeport , drill 2 holes and spot face.

I like your fix with the steel tubes, I think someone did something similar with brake line ?

Posted By: 440Jim

Re: Coan super sprag for street, strengths/drawbacks? - 10/17/11 05:29 PM

Quote:

For what it's worth, those shoulder bolts from Coan are not the best. The broach of the internal hex, is iffy, at best. The last one I used (3rd unit), I made my own spacers, out of steel tubing (like I have since 1978). MUCH better fit, and no worries about stripping the internal hex for the next builder to hassle with.

Thanks for the info/experience.
Did you use 1/4 bolts instead of the shoulder bolts and drill the case to 5/16 and make a sleeve to fill the case and fit the 1/4" bolts nicely?
Is the Coan race tapped 1/4-28?

The shoulder bolts look like a good idea, but if the hardware is marginal, that defeats the improvement. Although I don't like the compression ferrels to fit smaller (i.e. 1/4") bolts into the case, I have never heard of any problems with them. And many standard bolt-in sprags use that method.

Posted By: 1968RR

Re: Coan super sprag for street, strengths/drawbacks? - 10/17/11 10:32 PM

Quote:

Quote:

Bottom line: your sprag is less likely to fail if it's a bolt-in. They're not that expensive and there really is no drawback in using one.

Only half correct , The facory type sprag wit ha bolt in outer race will still fail by having the rollers rollover , the Cona or A+A sprag has more rollers so it is virtually impossible to have the rollers fail.

Just replacing the outer race to a bolt in type on a trans that has not had the outer race spin in the case is a waste of time and money.

You make a good point about the roller rollover, but even if the outer race has never been spun, installing a bolt-in sprag will still lessen the chance of it ever spinning (the force required would need to be much greater).