Fox T-Bird/Cougar Forums

Technical => Drivetrain Tech => Topic started by: 1badcougar on June 17, 2008, 08:40:14 PM

Title: driveshaft loop
Post by: 1badcougar on June 17, 2008, 08:40:14 PM
Is there anyone running a driveshaft loop here? If there is, what are you using? Does the fox mustang ones work on our cars?

I went to the track on Sunday and was spinning badly off the line. I was using a set of street tires that are down to the treads bars and had 20psi in them. I have a set of sprint car tires to use but need a driveshaft loop to get through tech.
Title: driveshaft loop
Post by: TurboCoupe50 on June 17, 2008, 11:09:02 PM
I forget which one I have on my car(may be Summit's own), but It's for a Stang...
Title: driveshaft loop
Post by: Carpimp1987 on June 18, 2008, 12:58:50 PM
I got UPR loop for the cougar i will tell you how well it works after its in.
Title: driveshaft loop
Post by: turbo83coupe on June 18, 2008, 06:52:35 PM
just put one in my TurboCoupe. One for a stang should work  :)
Title: driveshaft loop
Post by: billboehm on June 18, 2008, 11:42:42 PM
you may think i'm an idiot for asking but what's a driveshaft loop? does it keep the driveshaft from spinning out of balance?
Title: driveshaft loop
Post by: 1badcougar on June 19, 2008, 12:31:47 PM
Quote from: billboehm;224023
you may think i'm an idiot for asking but what's a driveshaft loop? does it keep the driveshaft from spinning out of balance?


A driveshaft loop keeps the front of driveshaft from from digging into / dragging on the ground or coming through the floor boards in the event the front u-joints fail and the driveshaft drops. NHRA requirements indicate that you must have one if you run non D.O.T. tires at the drag strip. I think that all rear wheel drive cars should have come with them from factory since this is kind of a safety issue.
Title: driveshaft loop
Post by: 86T-bird on June 21, 2008, 04:02:59 PM
I put an HPM unit for a Mustang in mine recently.  The install was very easy compared to the Lakewood piece I previously used.  The only thing to be aware of is the size of the driveshaft.  A stocker for a V8 is usually 3", if you have an upgraded shaft they are uaually 3.5" (hence my replacement of the Lakewood for the HPM).  I purchased the HPM loop from Summit for about $50 total.
Title: driveshaft loop
Post by: Carpimp1987 on June 22, 2008, 03:21:18 AM
thanks i was gonna try another UPR maybe for my other car or a lakewood but i will go look at the HPM Unit tomorrow or soon.
Title: driveshaft loop
Post by: 1badcougar on June 22, 2008, 08:05:39 AM
Thanks for the info. I'll look up the HPM. Still have the stock driveshaft but would like to upgrade to an aluminum one.
Title: driveshaft loop
Post by: martin0660 on June 22, 2008, 07:21:28 PM
FYI - The trapeziod looking one sold under the FMS / Ford Racing brand is the HPM piece. I also had the HPM piece under my TC in the day, and have it under my Capri with the FMS aluminum driveshaft.

I really like the design of that loop, and can still get my transmission out without removing the loop as well. ANYONE running sticky tires should have one IMO, even if they are "DOT".

Bob Myers
Title: driveshaft loop
Post by: martin0660 on June 22, 2008, 07:30:17 PM
Quote from: 1badcougar;223902
I have a set of sprint car tires to use but need a driveshaft loop to get through tech.


BTW - Have you ever driven a car on those tires? Are they fronts or rears (assume fronts to fit)??

A drag DOT tire / slick is built different than a dirt track tire in a lot of ways. Same with round track Asphault tires too. Basically a drag tire is built with soft sidewallys, but more plys on the tread for a solid tread face. Most of the dirt tires are 2 ply across the sides and face. The paved track tires are slicks, but have firm sidewalls for cornering.

I'm not saying not to use them, as I've seen it done, just be VERY aware that it's going to handle VERY different, and getting suprised on the big end is not the place to learn. Even Slicks /ET street type tires are a little scarry the first time you feel them slick walk on the big end. You get used to it after a while, but it will pucker you right up the first time they do it ;) Feel them out for sure.

Bob Myers
Title: driveshaft loop
Post by: Red_LX on June 24, 2008, 09:38:43 AM
I have the Fox Mustang loop from summit that I bought two or three years ago and still haven't installed :brick: because I haven't felt like pulling the carpet and all that fun stuff to install it.

However I found out recently that my car is at least capable of mid 13's...and according to the NHRA rules I found, anything running faster than a 13.99 is supposed to have a loop, street tires or not.
Title: driveshaft loop
Post by: martin0660 on June 25, 2008, 11:41:58 PM
Quote from: Red_LX;224452
However I found out recently that my car is at least capable of mid 13's...and according to the NHRA rules I found, anything running faster than a 13.99 is supposed to have a loop, street tires or not.


That is not correct as best I can see. I have both the NHRA and IHRA rule books and looked this up again to verify. They both say say that any car running "racing slicks" is required to run a loop, any car running 11.49 or faster needs a loop regardless of tires (street or slicks). There are some exceptionf for stock class cars, but that's not applicable to test and tune, or sportsman racing.

I'm not saying not to install it, and actually think everyone that races should add one. IMO its a critical piece of safety equipment, doesnt really hurt anything, and gives you some piece of mind.

Bob Myers
Title: driveshaft loop
Post by: 1badcougar on June 26, 2008, 12:51:18 PM
Is there a specific place where it is to be located? I heard 6" behind the front u-joint. It this correct?
Title: driveshaft loop
Post by: martin0660 on June 26, 2008, 04:51:34 PM
Quote from: 1badcougar;224698
I heard 6" behind the front u-joint. It this correct?


I think it's worded "within" 6" of the front u-joint, meaning no more than. If you get / use one of the ones that has been discussed, it's a little more obviuos where the flats are on the floor pan that it bolts too.

Bob Myers
Title: driveshaft loop
Post by: midget28 on June 26, 2008, 08:39:31 PM
i run a driveshaft loop on my car but its homemade fron 3 inch flat steel rolled and welded to the frame rails with 3 inch band and depending on your rules and type of racing is where you decide to put the loop its good to have one on the front of the driveshaft but i have a second one about halfway down the driveshaft as well incase the rear u joint fails..