I decided to make the switch from a snubber to the Calvert traction bars and single leaf springs on my 79 Cordoba. For anyone wanting to do this on a late B body, this is what you will have to do; For starters, I was running HD 3800 lb 5 leaf springs ( 22" front section ) with the front section clamped together plus a pinion snubber on my 9 1/4 axle. First problem you will run in to is the front spring eye bolt on the Calvert single leaf spring ( aluminum bushed ) is 5/8". Late B is 9/16" bolt. No big deal to drill out the front spring mount. Next problem is the ISO mounted spring system ( spring sandwithed in rubber isolators ). I originally tried to save the original ISO perches by strengthening them and resizing the spring locator hole to the 1/2" pin in the single leafs verses the 1 5/8" hole originally in them for the top rubber isolator. Don't bother, as you will find the diff to driveshaft angle to be about 11 degrees. I thought it would be close to my original set up ( 3.5 degrees), but it wasn't. I am attributing this change was caused by going from multi leaf to single leaf springs.?? At any rate, I ended up torching everything off and welding on a new set of spring perches from Calvert. BTW, they make the best I've seen. Next and last problem I ran in to was the lower spring clamp shock mounts. Earily B's had eyes on both ends of the shocks. Late B's use bayonet style mounts on the lowers. Make sure you specify or they will automatically send you the mounts for the earily B style shocks ( knee jerk reaction ). Weight savings = 32# - total. You have 3 choices of single leaf springs. Stock ride height, +1", -1". I opted for stock. Car sits 1/2" higher than old set up. It'll probably settle that much. Hope this helps anyone planning to make this switch. Won't be able to get out to the track again till after the holidays to see if there is any improvement.

Stuff I pulled off.

Stuff I put on.

Calvert perches

Original OSI system

Calvert "CalTrac" system.

just to let you know ,, friend of mine put set on 67 coronet
it was a little more invovled than just abolt on deal
as for any diffrence in 60 no ,, ran same 60 actually lost a bit !!
over the super stocks,,
he did build a bigger motor to and looser converter,still ran about the same as ss
as for the 'tunabiltiy' of the bars yes it can be done
but not easy,, have to have drivers weight in car to adjust very hard to do on the ground
so for my oppinon never buy again what a waste
for the monie just put ladder set up
either float it or coil it !!

Adjusting your Caltracs can be - interesting while the car is sitting on the ground. You will need a pair of 1 1/8" wrenches. Adjuster nut to ground clearance will be a problem - unless you have a spare 1 1/8" combo wernch. I obviously stole mine from a guy that owned a J.D. tractor ( green). Cut it in half and open up the box end and you are good to go!

What rear end is in that car ??

that is exactly what we did !!
cut the wrench in 2
mine not green tho a ha

me in the car

caltracs bottem hole ,#7 rancho 9000 shocks


drivers side just touching ..... pass side two flats preload

1.49 60 ft


drivers side two more flats . pass side two more flats preload

1.42 60 ft


again two more flats preload both sides !!!

1.40 60 ft


29.5 - 10.5 15 mt slicks on a 10 inch rim 13 pounds air preasure



you need to tune them , they work

well did that till 60 went away, stopped, went back other way till 60 stayed, and car did leave straight
on the phone with caltracs no help there ,
the car has had alot of changes in past 3 years
basical stock 440 running 8 3/4 stock springs 430 gears on gas to 12-0s to decent 440 moser complete dana w/456 with super stock springs,
running 11-teens,
now 474 with caltrac system complete on alcohol!
started with 9 'somebody' convert to 2 diffrent 8" turbo actions converts
so all we want to do now is run the car have a great time wheater we lose win draw have fun
because if it aint fun its no fun time to
do something else that is fun

Nice work John. Good documentation.

Looks good I am surprised they didnt give you the option of the B-body style lower plates.

One of the big issues with the f m j ars is the extreme shock angle, using the B-body lower plates lets the shocks stay a bit more verticle.

If youhave not braced you upper shock mount bar, get ready to and with the big tube shocks, keep an eye on it pinching your brake line.

This is the calvert F M J -body kit with B-body lower plates.

On the R/T ive thought about going to a shorter shock and make brackets in the frame rail to mount them verticle

Back on the ground. Ended up with 2.5 degrees at the trans and 3.5 degrees ( down )at the diff. Calvert recommends, as a starting point, to use 2 flats ( 1/4 turn) of preload on the bars with the car loaded per race conditions.

This is cool! Got any more pics of the car? what combo and what does it run if you dont mind sharing