Cal trac /mono leaf results

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dusterdragracer

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Well at out test n tune, with the 9" Ford diff.,Cal trac's with their mono leafs and shocks all around, I picked up 4 teeths over S/S springs and a snuber (which worked fine).
I did go from 4:30 gears to 4:57's,and left full on the converter @ 5500 instead of 4400 as I did all last year (didn't trust the 8 3/4 after I lost the 1st one on the 4th pass last year at TT).
I lost 2 miles per hr.though, but it was windy, along with crossing @ 6600-6700 RPM's. My motor is out of breath @ 6200, but it's O.K. because of the Eagle rods, Ross pistons etc. it can take it.
I was crossing last year at the beginning of the season @ 7200 with the 4:89's, but man I thought I wasn't going to make it to the finish line.
It also wheelies about 12" + and carries them out(pictures later), unlike how it left before, it kind on "stink bugged",pulling thw wheels up and out of the lights about an inch.Now it shoots out of the lights like this motor did in my Duster and glass Daytona.
I am running Hoosier 29.5 X 11.5X15 wide (13" thread), car weights 3175# w/out me in it.
It ran 11:07 and 11:08, good enough for me@ 4000' that would be 10:67-10:72 @ Seattle.Our track is adjusted 4 th's slower then sea level, which kind of sucks!
 
How did it do comparing 60's?

Now you can use that snubber for what it's good for... holding a door open. :)


Nice job.
 
Just the description,of chassis different reaction told me enough.
 
Sounds like a pretty good outing to me Chris. I agree with scamp that some shock tuning can get you closer and more consistent with the launch . Congrats!
 
Here is an email I sent to my buddy in Australia, with more detailed info:

1st test and tune,and the car worked perfect, does 8-12" wheelies (I was told, haven't seen pics yet) carrying them straight out just like the Duster did. I left full on the converter @ 5500 RPM's.Some how with wiring in the new shifter control, I missed the trigger wire for the rev limiter, so the starting line chip wasn't working.Oh well it likes it, because of the 'glide.
It ran a 11:07 then a 11:08. that would be 10:67-10:72 @ sea level. It had a better 60' time (1.555), then when it ran 10:86 @ Seattle last year (1.562).And the 11.07 which was the fastest it ever ran at King of the Hill last fall at Spokane's 4000' alt.(1.606) , remember,that's when I runnered up because I broke out more on a double break out(Iam Queen of the hill!),
Also, the car is more safe. When you let off at the finish line, it is way more stable. Which will be better for Tammy when she drives it later this year.
They told me, the new front shocks let it settle down better when braking.I was crossing at 6600-6700 RPM's with the new 4:57 ford diff. and gears.Sure is nice letting go of the trans brake button, and not worring about the diff.
I also started out by adding 0.20 in the delay box, and was still .005 red 1st pass, so I put another 0.20 in, and was .028, so that would have been .008. The delay should be at about 1.050-1.060 now, compared to 1.020 all of last year,which shows me the car is reacting much better.I was hitting the tree soft too (slower which is the way I like to hit it).
I thought I lost 2 MPH @ the finish line, but I didn't when I looked back at my past numbers for Spokane.
Only change for next week, is setting the electric shifter @ 2.50 seconds, instead of 3.00.I think it was O.K. but maybe a little shorter would be better.It most likely won't make a difference.

2 questions answered:
1st I still fell strongly about adjustable snubbers, they have worked great for years on all of my cars, but I know many disagree.
2nd Rear shocks were set at # 3 which cal trac suggested, I ran 12 lbs of tire pressue, and the front cal trac shocks do not adjust. I set the bars in the top hole, with 1/6th clearance.
I only took 2 hits, due to time dealys, next week is the 1st Summit series race, so no extra time for messing with it. It seems to be spot on consistant,as it was last year so I am good.
There were no other changes with engine trans, other then servicing it, and adding an electric shifter.
When someone puts pictures up, or we get some next week, I'll post them. The car is totally different, lower and new wheels.
Speaking of tires, I had no rubs, except the R/R on the inside a tiny bit, but not cutting.I pulled everything in an extra 1/4" when I put the narrowed 9" in,so now it doesn't rub on the outside like it did last year.Mission accopmlished!It was tuff getting 13" wide slicks in a mini tub.


Click here for pics:

https://www.facebook.com/media/set/?set=a.4124852885942.2142649.1421974018&type=1&l=a7615d73dc
 
What a difference Cal Tracs make:
Now and Before....That's + 3 teeths baby.
 

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That looks great Chris! Nice and flat coming out. I think that car has a lot of potential in S/ST given your baseline runs. Knock'um dead,:thumrigh:.
 
Thanks Rick,your allways an encouagement. It should be just fine. Would love a chance at the 5th's pro Tree, but that will have to wait. Next sat. is the 1st Summit series points race.We may run the divisional, but I need to make a belly pan to run S/ST.
Chris
 
Gotcha! Most others don't realize how tough/competitive the Summit bracket series is. You and the car are ready for it though. Let us/me know how it goes.

Good Luck, Rick
 
@ oldmanrick.....Well 1st summit race was good. I took out a 8 second S/C 58 Corvette. We both had terrible identical .036 lights.I found out now, the left lane lights .020 worse the the right. I kind of knew that, but didn't want to push it. It was 2 thou at the finish line in my favor. Justin Jewell is a super good racer. He just gave up a little strip.I was only 2 thou off my number, so it would have been close anyway.For him that is pretty hard to do, crossing @ 147 MPH to my 122!
Second race I had a 7 second Indy Mopar powered dragester. I was .012 to his .015, but it went 2 thou the other way, because I didn't run the munber.I lost it in the 60's. Found out from 2 friends, the car is leaving fine, then unloading the tires spinning 1 revolution. So I need to go softer on the shock settings. I also added a little pre load this week to the bars,because that is what my friend did.I should have known not to mess with a good thing.Every car reacts different to adjustments. I should have left them a lone. Lastly I noticed the rear shocks are almost totally collapsed in the ride height postion, so I think they may be bottoming out when it comes off the wheelie. Easy to make some extensions.At least most the heavy hitters went out early too.The division 6 E.T. finals are at our track this year, so we have double the cars......more at the 11 o'clock news!

Here is a link to a video. Look close at the rear tires when it leaves. Sorry for the quality, sun was in my wifes face:

https://www.facebook.com/photo.php?v=4841873050998&l=2729371710273157294
 
Looks pretty good to me from the vid too. Almost need slo-mo to pick up on the tire unloading.....lol. I need to watch a few more times, but if the shocks are not in the middle range at rest, i'm sure there's a little to be gained there. I'll get back if I have any thoughts, but thanks for the vid and I think you've done very well at this point.
 
Well, i've watched the vid many times and didn't see any real issues. Looks to me like you're hooking at the hit, so i'd think the added preload is working for now. I think your decent on the shock extension setting, but the rebound may be a little soft if your spinning a few feet out of the gate. The possible bottoming out would probably contribute to that.

Chris, even though I've been around cars that run 9's and 10's, i am by now means a expert. Just wanted to throw my thoughts out and if/when you see something wrong with my comments, please let me know. You have much more experience with these type/speed race cars then me. I always love to learn what works.:thumblef:
 
Thanks for all the positve info. My buddy said to adjust to 5 on the shocks, I was at 3, but actually that makes them harder. The info on shocks say if it launches and spins, go softer. My theory on the adding pre-load, is it didn't do this last week.
Agreed that it is hard to tell from video, but 3 of my real good S/St & S/G freinds, watching seperatly, came up and told me what it did. It hit the tires, went 20' then made 1 revolution.
The race I lost the 60' was like 1666, when the previous ones were 1567. I was off a 10th on the dial, so there it is. Only thing I can add, is our track is still green.Remember we are at 4000' so the 60's are lazier then what you may be getting.I run 11:07 here, which is 10:68 @ sea level.Almost 4 th's.
At any rate, giving the shocks some more breathing room won't hurt, and going back to the bars at 1/32nd clearance is where I was at.
Lastly I didn't add earlier that I am leaving full on the converter @ 6500, I didn't get my chip set, all I had was 4700, so next week I'll stick a 5000 in it, which will also calm it down.
Thanks Again guys your awesome, and I listen to all your input and form my opinion. So don't be offened if I don't do what you say, I do consider it all, then make the best judgement call I can.All cars react differently to the changes you make. I have a lot of passes in the car, but the rear chassis is new. At least now it's adjustable, so you can work with it.With all due respect to SS springs, you couldn't do much with them.
As I said before, I am going for points, so there there is not a lot of time to test stuff. I always make 2 adjustments, then on the last one I leave it alone. After all, the 1st pass normally doesn't even count.
 
It looks like it could use more front end travel. Do you have at least 5" of travel (the Calvert recommendation), and 90/10 shocks? You might have to get the front lower to get the full 5", which is hard to get on a Mopar. Also, make sure the suspension is lubed up well (no binding).

Don't take this the wrong way, but you really can't say whats wrong when you change too many variables at once (preload, shock setting, launch RPM). Start with a baseline tune (like what worked the first time), then make 1 change at a time to see what the car likes best. It will take a little time, but at least you won't be chasing your tail. JMO.
 
@70aarcuda, yes a 'glide.
@flyfish Thanks for the input. No, I don't take anything personal, I can tell by your tone that you are helping.
I do have full loose travel. Infact I had taken a front shock off friday, and made sure they were not topping out before the front end hits the limiters.They are not.After it hits the limiters, they have at least another 1 1/2" travel.
Yes, they are Cal Tracs 90/10. They extend like there isn't even a shock, then close slowly. I do have 5" travel, I can't lower it any more or it will be on the snubbers. I could cut a little snubber off, I did that on my Duster.
Making the shock extentions for the rear, won't change anything, it willl just help to make sure they are not bottoming out, so that is not really a change
Adjusting the bars back to 1/32nd clearance puts it back to where I was at the week before.
So the only changes I will really be making will be softening the shocks,and lowering the RPM's 500 RPM's (my prior posting was wrong, I met I was leaving full on the converter @ 5500, not 6500) A chip will make it more consistant, because depending on the time you are in the converter, the torque and Hp can very. In my opinion,when you limit it close to what your converter stalls at, then you will be more consistant on your launch. Besides that, no one needs to hit a full tree as hard as they can, unless you are going for E.T. and wheelies.Neither of those I am looking for.Fun, but not my goal.
Like I said, with the points thing on, I don't get any test time. Also, because our class is big, we may get only 2 time trials thrown at us, so that makes it even worse.
I also plan to call Calvert this week and pick their brain, they are very helpful.
If you also look at the post on FABO about CalTarc tunning,it says go softer, not harder if the car launches and spins. I was told wrong by my friend which way to adjust them.
There is one more trick up my sleve.I dumped my tubes this year, so that may have something to do with it, but I plan to do these things 1st.

Thanks again guys
Chris
 
The on going saga.....Well giving the shocks more room worked, no more hook and spin. But I lost another race, because now I spin at the hit inconsistantly.Ran a 11:05 off the trailer, then a 11:12, then a 11:07. So I put a 11:05 on the window (same lane as the 11:07) thinking it's cooler now, I cut a .009 to his .028, and he runs 11:08.5 on a 11:07, and I run 11:13.....he crosses .0498 ahead at the line, this sucks.On top of that, my electric shifter is inconsistant too. It works perfect everytime in the pits, but 1/2 the time on a run.
I am going to run a heaver wire to the batt direct, and if that doesn't do it, it must be RF noise.I don't have any problem shifting myself, but I would like to know for sure my helper is going to be there for me!
Back to the chassis. I went back to same adjustment I started with, no pre-load, and launched with 5000 chip instead of full on the converter @5500. It must be close, because there is very little stutter on the launch.I also went back to #3 setting on the shocks. There is no question they were bottoming out before.
So the only change was the 500 lower rpm lanuch.
We have 2 weeks before the next race, so I am going to go to a friday night race (not points race) and do some testing.
The sad thing is, all my Mopar freinds with similar cars and Cal Tracs, have a different opinion of what to do. More pre load, less pre load, top hole bottom hole, even though our cars are similar, different things work for different people.So I am kind of lost, I guess I will need to figure it out on my own.
Enjoy your week.My head hurts!
 
Well, I am still pulling my hair out. Nothing seems to work. We photo'd the back wheels on 5 hits with 5 seperate single adjustments. It seems to launch fine, wheels up, plants the tires hard,and as it moves forward you can see the tires start to come back up, then it is like someone jacked the tires off the ground till they are almost off, so they spin.Runs are all over the place,the exact amount the run is off, is all in the 60'.1-2 teeths.If it hooks, it's an 11:07, if it spins, it can be anywere from a 11:17-11:27...same MPH either way.All in the 60'.
The next day was a race, and we only got 2 time trials, I threw a 3700 chip in it, and it seemed to help, but got thrown off because it seems to have taken .020 off my reaction times.
I loose the race by .0018...Yup 18 10 thou.I cut a .036 to his .077 (I put 10 back in, because I wasn't sure about my RT loss)So it would have been .026 which would have won the race.He ran dead on with a little, I run 4 teeths off my number.
I am at shocks on hardest, bars in bottom hole, no preload, and 3700 with a 5500 converter.13 lbs TP.
My buddy is struggeling too, but he seems to think he found the sweet spot with 150 LBS in the trunk. Shocks on softest, and bars in bottom hole with 2 complete turns (not flats) of preload, and leaving full on the converter @ 5500.12 lbs TP.
I am going to test and tune next fri. and try this set up, but don't have much faith. Man I am disappointed. The car is faster, but I am a looser. I am down to 14th in points. I keep loosing rounds because I can't dial the car. I am fine on the tree,just can't guess what the car wants to do on the next run, so I just throw numbers at it..
I am beginning to think Cal Tracs are for Camaro's or work good for footbraking, but not transbraking.We will see. I see ladder bars in my future.
 

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I,m in the same boat right now,I,ve tried everything you,ve tried just not so hard on the RPM.Right now am at a Hemi shootout weekeng and if after my first run launching at 3400 with a well prepped trac.If I don,t see better than a 1.44 60ft I,ll be going back to foot brakin.Heck,I had 1.44 with XHD springs and a snubber.
 
Mine are 1554 if it hooks, 1650's if it doesn't...We are not alone, and the Cal Trac people as nice as they are, are no help.

P.S We are at 4500' and our clocks are adjusted,hence the slower E.T.'s this would be 10:60's at Seattle.
 
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