The truth about caltracs
Hi All.
We've ran Caltracs for 13 years and with 3 different engine combo's (soon to be 4) we've been through a lot of what everyones mentioning.
OK from the beginning, we expected to run quicker with them straight away but didn't over the old superstock springs and snubber system. The car was much more consistant and drove nicer up the track this was with an 11sec 440 motor (550hp at 3800lb). Since we are bracket racers it was fine. 60fts were in the hi 1.5 lo 1.6 range.
Next combo was a 528 Iron motor indy heads. This eventually got down to 10.00's initially it was in the lo 11's. Here we discovered it was hitting the tyre hard, lots of seperation. Tightening the rancho to max helped as did tubes in the slicks and more pressure. Altering preload didn't seem to help. We had to change both sides the same if we did, as it would drive to one side or the other. We also started looking at the front, slowing the rise at the front helped a lot, c/e three ways were set at 60/40.
We started to get the "porpoising" problems when we got a handle on the engine tune and started to go quicker. A smaller higher stall converter gave us 4 tenths and showed up the problem more. We needed more pressure in the tyre and more front travel. 60fts in the mid 1.45's
By now we had the 572 motor in and we are running hi 9's we've altered the front suspension to give us as much travel as possible and were are running a 29inch front tyre to get the ride height back. We are now doing the odd massive wheelie (175ft) and always pulling the wheels at least 2ft. 60fts are 1.40 with a best of 1.37 (good air). A couple of seasons ago we fitted afco d/a's dynamic strut rods and tubula uca's with heim joints, the lower stock arms are boxed. Also fitted travel limiters. We can now control the hit on the tyre using the front. Car is really consistent we've gone a best of 9.57 and 142.
The setup is still hitting the tyre a little too hard in my opinion so for next season we've gone for afco d/a's and an anti roll bar on the rear to help since we are putting in a 655ci motor. Car is getting all the stuff to run in the 8's and 150mph + but we're keeping the caltracs
HTH's