Caltrac info set up" hypothesis"

JD4440

<< Lo-Carb Monster
Feb 27, 2009
1,776
1
0
Orlinda, TN
when comparing our trucks to a viper doesn't the fact that out trucks are at least a couple feet highr come into play also ? Center of gravity is much higher seems like.
 

mb1

Member
Nov 15, 2009
149
0
16
Edmonton, Alberta
Squat from the suspension will always pull the rear axle up. It is simple physics. If the suspension is attached to the rear axle, and the force of the rear axle makes the suspension pull the chassis down, the force of the chassis being pulled down must make the suspension also pull the rear axle up. It's one of Newton's laws; I don't remember which one though

What I'm saying is, what if the suspension has anti -squat, but the force of the weight transfer is a greater force, causing a net effect of squat. I believe Trent will be able to gather a ton of info on this as he is able to experiment with his setup.



I see it a bit different. Certainly not to say I have a clue but, axle wrap ( tube torque ) seems to have the appearance of lifting the front portion of the leaf spring while, as the Caltracs are installed, changing the motion to minimal down force. At best, twisting the spring into an ' S '. I wonder what Newton says will be stored in that spring and what it alone plays in axle wrap trying to become neutral. Seems to me, only axle wrap is being controlled with a delicate balance between allowing the axle/tire to get under the truck for acceleration. Playing around seems to give me an indication that the axle is not lifting, as described above, but instead torque required to overcome available friction to the tires is easily overcome. If you will, negative caster.


I think suspension setup can control 2 factors.
1) traction. Will the suspension allow the axle to move a little bit to allow some dampening as traction is better or worse? Example: as you shift, the driving torque will unload a little bit then power will come on again. In a perfectly rigid setup, you would break traction the instant the power overcame the static traction force. With a little bit of give, the spring might flex a little bit as the power spiked, maintaining traction.

2) Weight transfer. Does your front end come up under accel? does the rear squat?


Note that I continue to say that no matter the form of traction control ( long bars, cal-tracs, top mount bars etc.) The lifting force on the front of the truck is the same. The Cal-tracs act to create a torque down on the front of the spring that will balance the force of the axle pushing the spring up. There is still just as much force pushing upwards. Now it is simply pushing in a way that doesn't wrap up the spring.
 

Madspeed

Fat Bastard
Mar 22, 2007
315
6
18
Elk Ridge Utah
From what I know Shocks are very important and most drag cars use a 60/40 shock. the reason is that rear end lifts and you DONT want a stiff rebound to stop it. and you DO want a stiff compression to hold it there same goes for the front end you want the front end to lift without any resistance to it. Remember those old Fox body mustangs? they would just about jump up in the air and LEAVE

As far as a 4X4? I just put in my front Dshaft in MaxBlaze did a 15Psi bosted launch and Shit my pants, it did all kinds of crazy shit. I need help to get this thing to work. I dont have a good posi in the rear it will peg leg, I do have a fresh Powerlock in the front and I think with my cal tracks I lifted the front end off the ground about 6 inches or so, somehow unloaded the rear and set back down one tire and made a very scary left. My freinds said it looked very violent and the whole truck basicly was coming off the ground. Both the front and rears caught air. :confused:
Anyone think a rear locker will fix it?
 

TrentNell

Finally underway !!!!!
Jul 7, 2008
7,543
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slc tuah
A lot of great idea's in here guys , a lot of them may be true , but only one way to find out ;) I have been on both extreme's , not enough weight transfer , and too much , I believe the truth is in the middle and am searching for it constantly , maybe one day i will get lucky !!



From what I know Shocks are very important and most drag cars use a 60/40 shock. the reason is that rear end lifts and you DONT want a stiff rebound to stop it. and you DO want a stiff compression to hold it there same goes for the front end you want the front end to lift without any resistance to it. Remember those old Fox body mustangs? they would just about jump up in the air and LEAVE

As far as a 4X4? I just put in my front Dshaft in MaxBlaze did a 15Psi bosted launch and Shit my pants, it did all kinds of crazy shit. I need help to get this thing to work. I dont have a good posi in the rear it will peg leg, I do have a fresh Powerlock in the front and I think with my cal tracks I lifted the front end off the ground about 6 inches or so, somehow unloaded the rear and set back down one tire and made a very scary left. My freinds said it looked very violent and the whole truck basicly was coming off the ground. Both the front and rears caught air. :confused:
Anyone think a rear locker will fix it?

those idea's def work on a 2wd , but my experience on a 4wd IFS says other wise , now on your solid front axle front end it may work , but on a IFS like the rest of us run , you arent allowed much front end rise , when the front end rises the camber goes way positive and you end up loosing most of your contact patch and in turn the front tires break loose .
 

jckleewein

New member
Dec 13, 2008
422
0
0
Broomfield, Colorado
Has anybody done any additional testing on these caltracs? I have a set that I haven’t put on yet. Just wondering how everyone is setting these things up, and do you notice a difference at the track.
 

NJ_LLY

Back in action
Nov 4, 2008
560
0
0
Browns Mills, NJ
I had my truck at the track today. My suspension setup is as follows: QA1 single adjustable fronts 12 clicks, Rancho 9000 rears maxed out and Caltracs in the highest holes. My fastest 60' today was a 1.70 spinning BAD. All day I played with the setup and made 9 passes but dont feel I made any progress as I couldnt get the truck to not spin. This was not on street tires it was on M/T's. All of my vids show the rear only squating minimaly but the front raising rather quickly. My research has shown me that if they are too stiff the tires can't rebound fast enough and it in a sence hangs the front which chatters the tires and makes it hop. Too loose and the front will raise so fast that it yanks the front off the ground giving the same effect. Currently Im at a loss as to what to do next. Im hoping that the reason I spun so bad was the track conditions. oh and my tires were at 22psi front and 20psi rear the air temp was 48*. I think what frustrates me the most is that iv never had as good of 60's as when my springs were just champed Im a full tenth off with about 150 more hp.
 

paint94979

Beer Nazi
Sep 18, 2006
11,715
8
38
37
I have no hard evidence but after installing Caltracs today it is a night and day difference... at the track I could only launch at 12psi and it would still hop and spin very bad, today however we launched it at 18psi on a dusty cold road and it barely spun... very impressed so far. Track times to follow
 

Colt

New member
Jul 23, 2010
523
0
0
Best $200 you can put back there and launch straight and hard. Instructions are easy and very clear. Adjust to the work at hand takes 2 hrs. with a lift and a 12 pack of Sam Adams for us to install. Love the way they work once you have a set under your truck you start to notice how many guys have them on all kinds of rigs. Strong materials too when you go over them with a good old check over.
 

zf>allison

you never had your car.
Apr 30, 2013
3,394
0
36
elsberry mo
I've been reading on yellow bullet forum and on drag cars that are on slicks the upper hole does a better 60. But we're a different animal. So if I don't hear anything I'm just gonna try it. Plus mines a stick so launches a bit different than an auto, so going against the flow could help.
 

x MadMAX DIESEL

<<<< No Horsepower
Dec 30, 2008
7,535
1
38
34
Lexington, Ky
I've been reading on yellow bullet forum and on drag cars that are on slicks the upper hole does a better 60. But we're a different animal. So if I don't hear anything I'm just gonna try it. Plus mines a stick so launches a bit different than an auto, so going against the flow could help.


It will obviously push down a lot harder. You have a lot more ratio working for you with the same travel!!


Sent from my iPhone using Tapatalk
 

zf>allison

you never had your car.
Apr 30, 2013
3,394
0
36
elsberry mo
I'm gonna put it up at least to the middle hole tonight I hope my bars are long enough since I have drop shackles. Hope it bites alot harder
 

zf>allison

you never had your car.
Apr 30, 2013
3,394
0
36
elsberry mo
Man I miss threads like this.

Seems like it's all figured out now lol.
But on a side note thank god for this thread, bars wouldn't reach on the top hole so I went to the middle one. Did three launches to make sure there's not a fluke going on and it's simply amazing what it did. Now I haven't ran it at the track but back road test was way better no hopping at all. I was slightly rolling back on one launch and it still just took off like a Cadillac. It spun all 4 once but still didn't hop one bit, really feels like it bites alot harder in the rear. Like the rear is pushing it now instead of the front dragging it. And that's still with bad stock shocks so good shocks should help even more.
 

zf>allison

you never had your car.
Apr 30, 2013
3,394
0
36
elsberry mo

I've read that top link but not the bottom. I know mine is gonna leave more like a trans brake car. But i make the pins just touch, by pins I mean the rubber buschings mine came with around the roll pin. Because if I don't the truck wheel hops under gradual accelerating. Now at the track maybe I should back them off for just launching the 3 turns like rob stated. Maybe that will be my next trial. Would actually help because my bars seem on the short side so that would get the heims back in the tubes a bit. I always read put em level to the ground. But mine acts way better on the middle hole I know that much. And i always did a half a turn of preload now I make em just touch and I can feel it hook in the back now, not like it's on ice anymore out back