It appears my new motor has more torque than the last one. It is giving me some pinion twist causing a vibration in the drive shaft when I accelerate. both ElPolacko and Kerry suggested Caltrac type bars. Is anyone using them? The website for calvert racing has nothing. What do they cost? I have some DOM and 3/8 plate, why can't I make my own version? Any experience or comments will help. TZ
i put the setup on a nova i built for a customer......wuss won't get it out of the garage.....i used these with a landrum parabolic spring....and a pair of rancho 5000 shocks.....(i think that was the number) ....i bought the complete setup off of a guy named dustin rhodes ....he rant eh same setup with a 30x12.50 et street in real street at the time .....was running like 9.0's no bottle ....doing a 1.20 something 60'...they obviously work ....heck calverts stocker mustang was a s/s record holder ....and its not tubbed....calvert said to make sure you have a long enough shock .....as that was usually the problem with most guys that ran leaf springs......the car would bottom the shock out....and unload the ch***is....and blow the tires off.....not a whole lot to the setup ....just aluminum spring bushings with a steel sleeve that pivots.....with the brackets on the sides of the that.....and the adjustable bars...brandon
Comp Engineering has something similar called Slide-a-Link. I know guys who have used the Cal-Trak bars with success. They are easy to adjust and they hook up! If you have any specific questions I can ask them. If you are interested, I could measure up the Slide-a-Link bars at work for ya so you can whittle up your own set. Mike
I have them on my daily, they do work and keep it allot straighter. I think they were about $300 when i got a deal on them. They do require you to replace the front spring bushing with a solid aluminum piece. They are easy to adjust to add or subtract pre load. In simple terms they are a bell crank system that re- apply the diffs desire to point up and transfer the force back to the frame so the spring don't go into wave motion and wheel hop central and in design help lift the front to plant the back some. I have old stlye traction master on my olds and the difference is the caltracs are not locked into one postion like a static bar. Do some googling for traction bars- theres a guy who had a whole write up on making your own cal trac's that he did for his truck that was good. If you buy good parts to make a set it will be over $100 without your time to design it and make it work. good luck, danny
Have you checked your pinion angle and made adjutments? It sounds like there is not enought angle there. It should be nose down in reference to the drive shaft. Something like 5-7 degrees on a leaf spring car. Those numbers might even be a little low. I am sure someone will chime in with a more accurate amount. Keep in mind this is between the driveshaft and the pinion ... not pinion to mother earth. FWIW...Caltracs will ride like a buck board if you have them preloaded as recommended. They are great for Drag racing, but a bit harsh for a cruiser. Peace and Good Luck!
Thanks Kerry That is exactly what I was looking for. I already had a sketch made from a boring meeting this morning, your link helps with the geometry. I am thinking 4bar bushings on one end and rod ends on the other for adjustment. Is there any need for the solid spring eye bushing on a street car, I plan on using the replacement stock bushings I picked up last month. El T-B I don't plan to pre-load them since it is a street car, they won't be as efficient but that's fine for what I need. Yes I have checked the pinion angle at static and everything is where it should be. The problem is my new torque monster engine wrapping up the spring.
What he said,"they ride harsh".LOL Put some on a 70 Camaro for a customer with a 406 sbc and 250 hp nitrous with 10 slicks,Worked awsome.Wheels up about a foot forever. T.OUT
They're adjustable...only harsh when you set them up stiff. We ran them on my BB '69 Camaro street/strip car when i was younger. W/ M/H cheater slicks, a Moroso Brute Strength posi, 4.11's, and a lot of torque, that car would hook hard! The problem we had was getting it to go straight out of the hole. You load up one side just a little more than the other and it gets kind of ugly fast.
I run them in my 66 427 Fairlane, they work great!! Little noisy on the street if they are not preloaded. With my old 390 I cut a 1.86 60' with 235/60/15 BFG drag radials. If you need any dimensions feel free to ask, I am a machinist by trade if you need anything done.
Hell yeah! That link Kerry posted is excellent! Seems if they are so easily adjusted, you could run them with a small amount of preload for the drive and then crank them up at the track. Yes? No? RASHY?
Kerry's link is the original one i was thinking about- good find flt-blk- all the force is transfered forward from the diff. to the front spring eye- they use the solid bushings so not to lose the energy on deflection- the bushing is the pivit point if you check the sketches- rubber may make it do odd things. I run mine a hair away from touching- Little noise if you keep them well lubed and they did little to change the ride of my truck. The standard models have two hole settings for more adjustment, they also have a lowered model with less material hanging down. the key measuremnet is where it hits the spring, which determines how big the triangle is. I found off road places had the most selection for parts, mr rash- you are totally correct- most street driven stuff will only have a small amount of load if any- for the most part it will just keep it straight, serious folks at the track can use them to tune their suspension for more of the variables, like temp and traction. danny
According to the site pivot point to pressure point distance = pivot point to transfer point. Why do these need to be equal? Is there a calculation for determining how much the spring deforms Vs the lever pressure from rotation? I don't want these things to hang down that far if there is no good explanation.
John Calvert is a really nice guy. His S/S Stang is a stick too. That ****er ****s and gets with his bars on it! Runs a 10" slick too! Last time I seen him he was running SS/G with it. Here is his web site http://www.calvertracing.com/
I ordered a set for my 57 Chevy, super nice people to deal with. They already had sets ready to go for 57s. I asked if I would have enough adjustment seeing how I moved my rear end back 5/8 of an inch. by drilling new holes in the rear end spring pads. He said yes I should have more then enough adjustment, but he said its not fair to me not to have full adjustment so they made me a custom set in 3 days, no extra charge. Very high quality parts!
Kerrys link is one I have seen and used before for guys around here. No sense in re-inventing the wheel. I have scaled the fulcrum down for ground clearance issues but otherwise performed great. You should pre-load them for racing and you can load them differently as someone suggested for better launch charicteristics.
i would go with the compe***ion engineering type bars. i put some on my friends 69 camaro with a 427 & 4 speed. work really really well and were pretty easy to adjust. i would stay away from making any bars similar to the traction masters. i have some on my ranchero and have sheared the axle centering pin 4 times.
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