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Shelby drop and lowering spring

Well I'm back. Things are pretty good. I still have wheel bounce though. :(. Not initially but after a few feet. So I have a question. Currently I do not have any vibration issues at all (and don't want to create any). But I was thinking I should check my drive shaft angle with the rear 9 inch differential. How do I do that? Lol. Pics or a sketch would help.


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Well of course I googled and I understand the concept. So I'm just going to assume my angles are correct.

If I did get caltracs and set it up so there is very little pre load, will that make it a decent ride?


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To measure drive angles, you must add or subtract the component angles. The relationship of the angles between the transmission, driveshaft and the differential, on each side of the driveshaft (drive and driven ends). This example shows 3 degrees of angle up for the transmission, 7 degrees up for the driveshaft and 3 degrees up for the differential. Please note that the transmission and the differential are parallel, the rules of geometry guarantee that the two operating angles will also be equal + or – 1 degree. Even though you know that the operating angles are equal + or – 1 degree, you must still calculate the operating angle (what the U-joint feels) to be sure that they are within specifications. Elbe U.S.A. specifies a maximum of 6 degrees of operating angle, with lower speed applications exceeding this limit. Because all of the angles are up, you need to subtract the smaller component angle from the larger component angle at each joint.
Angles_component.png
 
You are likely getting quite a bit of flex in the body without connectors. That could explain the wheel hop as the body relaxes after initial torque is exhausted. Even new, unibody cars like these flex quite a bit. Welded in subframe connectors are usually the first upgrade for performance from a chassis perspective. I would start there. I went with a set of Tin Man connectors and cannot praise their design and construction enough. Heavy walled box tubing that slips inside the existing front subframe for a very solid mount. The whole chassis lifts as one now when jacking. No flex. At all.
 
I agree with Terry, I have welded-in (thru the floor even) sub-frame connectors. That might be why I don't get wheel hop with mine
 
You can see the sub-frame connectors in this pic, they tie into the frame and go thru the rear floor pans. They make contoured ones but these are supposed to be stronger
IMG_3521.jpg
 
Is it mandatory to weld the forward attachment?
Bolt-ins don't do the job any were as well. To be done right and gain the full benefit you need to fully weld them in. That means welding not just at the frame connections but along the bar length too. Doesn't need to be every inch of the length but a few spots along the way welded to the floor panel makes a difference.
 
Bolt-ins don't do the job any were as well. To be done right and gain the full benefit you need to fully weld them in. That means welding not just at the frame connections but along the bar length too. Doesn't need to be every inch of the length but a few spots along the way welded to the floor panel makes a difference.

10/4!! Sounds like this will be my next task! :)


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mine is welded all along the length, mostly because it is actually protruding into the car but yeah welding is the only way to get the full benefit. It basically becomes a structural part of the chassis. My car didn't have a passenger front torque box so I added that and welded all the seams on the shock towers and frame rails and even added the Boss 302 shock tower bracing. I figured with a a heavy big block I need all the strength i could get. It must work, car feels very solid. Besides drag racing I have done some open track with it and handles surprisingly well for a nose heavy car
 
mine is welded all along the length, mostly because it is actually protruding into the car but yeah welding is the only way to get the full benefit. It basically becomes a structural part of the chassis. My car didn't have a passenger front torque box so I added that and welded all the seams on the shock towers and frame rails and even added the Boss 302 shock tower bracing. I figured with a a heavy big block I need all the strength i could get. It must work, car feels very solid. Besides drag racing I have done some open track with it and handles surprisingly well for a nose heavy car

Does the tin man deign
6264796bd50e3c97f6ba22dd7b0c52a2.jpg
trap water in the channel as its appears its a three sided tube ( I live in FL lol) . Also I did a quick look and its obviously hard to tell what's good or not any other good suggestions? Are the TCP any good (not the complete cross over). Just the longitudinal sub frames.




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The Tin Man pieces are fully square tube. They fit extremely tight to the floor which, next to rigidity, is the second most important thing you want. They ride higher than a tight 2.5" exhaust pipe! My research indicated that the TCP and most other did not fit as tight. Plus, from an strength standpoint they are not made from the same material "mass" as the ones I went with.
Any decent set-up (welded) will do the job, I'm sure. I like that when I put a jack under the rearend on one side, the whole car instantly reacts to the first jack pump. Like it is one solid piece. Prior to that was quite a different result.
 
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