These were actually modeled after the ones from a Sunbeam Tiger. I have originals off a Sunbeam tiger and have been running these since 1988! Anyway, here is what I've done to help fix my problem:

Took out equa-lock and replaced with Detriot Locker with 4.10 gears. Sold Nitto's and went with 26 x 11.5 M/T ET Streets. Competition Engineering drag shocks 90/10 front, 50/50 rear. Removed sway bar. My last time out at the track, I snapped a u-joint on my first run. LMAO!! I was pissed. Trailered my car an hour and a half for that?!?!!? I think I need to work on my leaf springs and my coils because they are original '67 equipment. On a different thread, everyone suggested 6 cylinder springs, but I just found out that a 67 Stang w/ a 289 and a manual trans comes stock w/ the same springs used in all of the 6 cylinder models. (I have a transplanted 351W btw.) Anyway, my goal is to have a 1.6 60 foot time spraying a little bit at the launch. I'm open to suggestions. Thanks for reading this long arse post.

http://www.baselinesuspensions.com/info/Launching_A_Drag_Car.htm
............Jay

quote:

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Originally posted by ericcasas:
...My last time out at the track, I snapped a u-joint on my first run.

...I think I need to work on my leaf springs...

...67 Stang w/ a 289 and a manual trans....
...my goal is to have a 1.6 60 foot time...

I'm open to suggestions. -E

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Eric,

You didn't mention it, so I'll ask: Have you braced your leaf spring perches at the housing yet? If not, do a M&M 'Search' and seriously consider it.

How about a driveshaft safety loop? If not, sounds like you're past due for that! You may want to consider upgrading to Severe-Duty U-joints.

What about axles - are you running 28-spline OEM axles? If so, before you twist them up, you may also consider switching them out and moving up to aftermarket axles; or up to even stronger axles by moving up to a 31 or 33-spline axles, but then you'd need to up-size your Detroit Locker as well.

Do you have a 8" or 9" rearend?

Are the ET Streets spinning or not when you launch it on the ET Streets?

Maybe look into some Rancho adjustable rear shocks....

Jack up your front end and see how free your front syspension hangs. You may want to consider some heim joint lower control arms or bronze-bushed coil spring perches to loosen up the front suspension & get the front up quickly and the weight transferring backwards at launch.

I did have cheap cast iron u-joints (with grease passages) and I'm pretty sure that is why it snapped. I have a driveshaft safety loop BUT it is sitting in the garage collecting dust. >8\ I since went to Brute Force solid drop forged U-joints front and back and dont see how these big ol thick u-joints wont be able to hold. I look at my pinion angle and it seems solid. I dont know how to measure other than by looking at the vehicle under a load and empty. I haven't had a chance to take the car out, do a burnout, and then see how the tires would hook under a 'drag launch' condition. I can't answer the question about them spinning or not. I would like to think that they would spin quite a bit. I usually rev up to around 5K RPM and then just dump the clutch. (I shift right around 7K.) I haven't even finished putting in the Detroit Locker yet. It is a 28 spline on a 9" rear. I just got this whole set up so I want to stick with it for a while. The day I go to a 33 spline axle is the day I will probably go coil-over and mini-tub as well. That will more than likely be a few years down the road. About the leaf spring perches, they are not braced to my knowledge. I totally see why they would need it but honestly have never heard of anyone doing it. I will look for that thread and read about it. I guess my plan of action will be this:

1.) Keep my current front springs per your advice.

2.) Get new 5 leaf 'stiff' rear leafs per the advice found on the baselinesuspensions.com link provided by Warhorse.

3.) Brace my leaf spring perches and install driveshaft loop.

4.) Check my front suspension for free movement to make sure it's not binding up on me anywhere.

Anyone else have anything to add??

quote:

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Originally posted by ericcasas:

"I have a driveshaft safety loop BUT it is sitting in the garage collecting dust."

-- OK, fine. Now make a plan to get it installed BEFORE you need it again....... If you were only running normal street tires, I wouldn't worry 'cause then they'd be your 'weak link', but because you're running a manual trans and ET Streets, I'd get the loop installed. It goes 6" behind the front U-joint. Get it in BEFORE you do the next burnout with the ET Streets on.

"I look at my pinion angle and it seems solid. I dont know how to measure other than by looking at the vehicle under a load and empty."

-- Borrow an angle finder or go to Sears and buy one. Here's what you are looking for - click here: http://www.sears.com/sr/javasr/product.do?BV_UseBVCookie=Yes&vertical=TOOL&pid=00939830000&subcat=Levels+%26+Protractors

"I haven't had a chance to take the car out, do a burnout, and then see how the tires would hook under a 'drag launch' condition. I can't answer the question about them spinning or not."

-- Ok, fine. After you've installed the driveshaft safety loop and had the spring perches reinforced, then take a friend with you to the track; (just because you can spin 'em in some parking lot, doesn't mean you'll spin 'em at the track after doing the burnbox) and have your friend watch your tires when you launch.

"I usually rev up to around 5K RPM and then just dump the clutch. (I shift right around 7K.)"

-- You may want to lower your launch rpm a tad, it will be dependent on whether or not your spinning at launch. You want to adjust your launch rpm so you only spin the ET Streets maybe a half of revolution.

"I haven't even finished putting in the Detroit Locker yet."

-- I read that you REPLACED the equa-loc with the DL.... Apparently that isn't quite correct. YOU'RE GOING TO replace it with the DL. OK...fine.

"It is a 28 spline on a 9" rear."

-- Ok, so they're 28-spline and it's a 9" rearend. Are they OEM axles? If so, again I'll say you may want to seriously consider selling them while they're still straight and upgrading to some Moser or other aftermarket axles that are not 25+yr old.

"About the leaf spring perches, they are not braced to my knowledge. I totally see why they would need it but honestly have never heard of anyone doing it. I will look for that thread and read about it."

-- If you didn't brace the perches, then it's pretty likely that they aren't braced. Read about it here:

https://mustangsandmore.com/ubb/Forum12/HTML/010160.html

"I guess my plan of action will be this:

3. Brace my leaf spring perches and install driveshaft loop."

-- I'd move this task to #1, Bub!

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I agree with XR7, CalTracs would work better than the old Traction Masters that you have now.... but, all in due time. Once you determine your pinion angle (with the tool, not by eye) then you may need to install some wedges as he also indicated.

It'll all come together in good time. Most of all, remember, 'Safety First' & try not to wreck stuff. Save/budget the funds for the parts while still keeping milk in the frig and soup in the carboard and then upgrade your drivetrain gear as you go. Then you can sell off the OEM stuff before it gets twisted or broken.

Besides, having a broken car at the track is NO fun at all. Even if you have a car trailer, you still need to get it loaded!

quote:

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Originally posted by ericcasas:

I thought they should actually make a few rotations! No??

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Eric,
If you're spinning your ET Streets, you're not moving forward as quickly as you should!