anybody know how to make cal tracs work with a straight axle 1955 chevy? cuz all i've done is roasted the tires...including slicks...no traction yet. got a 1964 ford straight axle under the front, coil overs...speedway leaf springs...5 pack rear leaf springs from danchuk, pocket kit, monroe shocks, 3" lowering blocks in the rear, geared up to hopefully pull the wheels... running a crate gm 454, doug nash 5 speed, and the car is super stiff...but it won't hook up for nothing...slicks...the car just winced and got wheel hop. here is a couple of runs at the track... http://www.youtube.com/watch?v=5vIj5caPMmU cal tracs seem to work with a arms not straight axles very well...i don't know...any suggestions.
It appears from the video that your front end (shocks) may be at full extension, when the car is at rest. I would start with dropping the front 3-4 inches and allowing the front end to lift, transferring weight to the rear upon launch. Then you may be able to tell if the the rear shocks/springs are too stiff also.
X2 on the front being up. Also, can you post a couple of pics of the Caltracs setup on your car. Pretty sure I was seeing a lot of wheel hop as well as tire spin.
It looks like a lot of 'rockin' motion (ft to back) during the the 1st 100 feet. It does need to plant and stick. Are your leaf spring packs rebuilt/relined and new eyelet bushings? Rear shocks typically are 50/50.
The lowering blocks could be screwing up the geometry of the cal tracs. Most people have good luck with them. Blue
The car appears to be way to stiff. Call Cal-Trac and tell them what you have, they are real good at helping racers out. We redid a Nova that had Cal-Tracs after the told us what we needed worked like a charm. Good luck Pat
I'd get rid of the blocks. They give the rear end extra leverage to flex the springs and create wheel hop.
And, heat them tires, didn't see a good burn out, do the burn out when the car in front of you leaves the line, don't let slicks cool down, don't back up or dry hop, big burner up to the prestage. Drive your car like you hate it, don't let the track staff rush you to burn out too soon. Like it was said before, check with Calvert, good people. Got 'em on my 65 Coronet 440 dorkflite 4.56.
What shocks do you have on the rear and front? Call us and we can help. M-F Days 10am -6pm CST 219-861-1214
well i saw a couple things from the video. it looked like the slicks were still cold on the launch. the front end didnt seem to have much extension travel. the cal tracs like about 2 degrees of negative pinion angle and it looks like you need a little more preload on them. you really shouldnt run any more than a 2"block if at all with them. also what psi are you running in the slicks?
without lookin at your setup its hard to tell whats causing what. and the video dont tell the whole story. but the guys here have it it about right. the straight axle set ups were for transfer, well your not transfering.you front goes up but gets pushed right back down. too much rockin the boat. thats what you want in your van not the racecar.lol. lots of questions. what kinda slicks what air pressure.shocks? the front should stay up while the back is planted. of course you know that. what kinda spring rate in the front back?and take them blocks out.would really like to see pics of it udermeath. i use to run a 55 back in the day. best car i ever run.
You are way too stiff on your spring combination. I order to get a car to transfer weight, you have to allow the combination of the front lifting and the rear dropping at the same time. The forward/aft rocking motion I am seeing in the video is telling me that the front and rear springs are fighting each other. You have to dissect this one piece at a time. The earlier comment about the front shocks being too short is a good place to start. IF they are too short, get the right length shocks and use a drag-style shock like a 70/30 or a 90/10, which will allow the front to raise quickly on the launch and slowly compress as the car goes down the track. Don't run gas shocks. Also, find out what the spring rate is on the front coilovers. On the rear, take the blocks out. Your pinion angle is probably out of whack because of it, and that plays a huge part in getting the rear to plant the tires. CalTracs work awesome, but there are a few things like pinion angle and the spring rate of the leaf spring that play a huge part in making them work correctly. Call John at Calvert Racing and he'll give you some great advice on what you need. He designed the CalTrac, and if anybody knows how to make them work, it's John. Just remember though, that if you spend the time to make a straight axle car work great on the track, it's going to make the car a little more spooky to drive on the street. Changing the shocks to a streetable shock after you get back from the track is a good idea. Keep us posted and let us know how it works out.
John Calvert knows how to make them work on any car. Call him. (661) 728-9600. No need to call anyone else. Whether or not you follow his recommendations is then up to you. It may involve changing things, as in "my car is super stiff". Which in drag race speak equals "it will blow the tires off".
I use ladder bars.....Coil Springs.......cars sits down a little and lifts wheels.....my issue was earlier clutch.....was slipping right when it was ready to lift.....$700 later and the wheels come up @ 6500 RPM 283 cu in and 2 bbl.
i've made some changes. it doesn't bop anymore. i noticed the burnout wasn't long enough to really heat up the tires. took note of that too. took the coil overs off the front end, installed some simple monroe shocks in the front, the front just doesn't move that much. installed some rancho shocks in the rear...it helped a little, but not enough to get it to really stick. it's just too much weight on the front i guess. the more weight i put in the trunk the better it seems to hook with street tires. haven't gone to the track in a couple of months...responsibilites taking priority right now. i took the lowering blocks off and it just made it worse as far as traction. i got a few more things to try out. but as a few said (what makes it perfect for the track makes it dangerous on the road) this car ain't even that fast, 8.5 in the 1/8th. i drive it on the street about 95% of the time. so i guess i gotta make a decision...dedicate it to racing and scrap the street driving idea or just leave it alone and drive it on the street only. as far as the slicks when i raced...i borrowed them from my uncle. 26" 9 wide, they are super old tires now...10 years...the compound is probably to hard now. that's probably a problem as well. till i buy my own i will be able to really tell. i also had the 5 leaf brand new from danchuk. ended up taking one out. running four now. the leafs move more than before. not as stiff. but i still have a few more ideas on what i can do. about the only way to lower the front end is to go back to the stock frame again. i got another 55...a ht...maybe i will just fix that to daily drive and just build this to race.
You are in CA so talking to Caltrac is good advice. If you don't want to do that, at least post pics of both the front and rear suspension. Show detail of how everything is mounted. Tires are the number one issue. Without great rubber, you have no hope of making the suspension work. Number 2 is that on a test and tune night at a lot of tracks there is no real track prep. Look at other cars. Is anyone that night hooking up? Number 3 is rear shocks have to control the rear suspension. Caltrac will insist that you buy their adjustable drag shock and they are right. After that I would also go to a drag shock on the front as well. By then, it should start coming around. You may have to end up going to an adjustable pressure plate (clutch) depending on your engine combo to get it to really launch (I can't really say... not enough detail on your set up at this point.) I have some good suspension video if you look at my channel in you tube.
There is no reason you can't make this car work on the street and the track and be safe doing it. There are ALOT of 55 chevies out there that hook so it aint cuz ya got to much weight in front it is because you are not transfering it!What are "simple Monroe shocks"?Do they have 90/10 valving?Did you cal John? Why make it harder than it is? Call John tell him what you have then do what he says...Do not try to reinvent the mouse trap,find out what works and do it !
You need to get a handle on what's going on. For the record, weight doesn't transfer, LOAD transfers. I'll say it again, LOAD TRANSFER. The front spring eye and axle centerline create a lever. The caltracs aim to extend that lever, or stiffen an already optimum leverage. Your lowering blocks are changing the dynamics of that function. Add to that, the wt you've placed up fron with an iron BBC. Look at it as a giant 8 ball that you're behind. Now you need to get that 8 ball to "tip back", or transfer load to the rear of the car. Once it is transfered it needs to stay there long enough to get out of the chute quickly and efficently. Good ol 90/10 shocks were intended for this. Extend easy, compress with 4 times the resistance (theoretically 9 times). Now upon launch, with good traction, the front end extends and stays there taking the car's CG further back and keeping LOAD (there it is again) on the rear tires until shit settles down and you're charging for the stripe. While pictures can help, other similar set ups can be compared, you really need to have just a small handle on what it is you're trying to do. Don't go for "squat", don't try to pre-load rear tire force, move things around until you get good load transfer. Non of this will work efficently w/out good slicks. 10yr old 26" slicks are the 1st issue. The best rear suspension in the world is worthless w/out traction.
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