Daily Driver/Weekend Racer - Race Prep

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r-n-r

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I am wondering what people are doing to set up their daily drivers for the track on race day. I can run in low 13s but I am looking for 12s. I know I need more power in the motor for my goals, but what do you do to prep for a race?

How much of a difference (is it worth it) does dropping the 2nd battery, spare tire, tail gate, junk from under the seat, etc... make for weight reduction?

How about the little front tires the big boys run, any value in using those in the 12 sec range?

Are there any adjustments to the suspension that are performed at the track?

What else is there to squeeze out some ET?

My focus is 2wd, but I expect 2wd and 4wd info would help us newbies.
 
Well this is what I posted about my track visit last night on another forum.
Met the guys from Hot Rod Diesels at Houston Raceway Park last night, they were doing some test/tune runs on a couple of trucks. I decided to make a couple passes with the daily driver stack I have been running for the last month or so. This stack has improved my daily driving mpg by 2+ city and highway. All city 15+mpg and all highway at 75+mph 19-20mpg.

TST R49 05tt 3/0, EZ 1 and Smarty #6.
12-14psi 4wd launch.

1.93 60'
8.43 1/8@83.3mph
13.22 1/4@102.5mph

TST R49 05tt 4/0, EZ 1 and Smarty #6
14-15psi 4wd launch.

1.93 60'
8.37 1/8@84.1mph
13.13 1/4@102.3mph

On both runs my BD BOV was bleeding off boost at shift points, I gotta get a cutoff switch on that thing for the track. Would have been a little better without pssst, pssst all the way down the track. However I am very happy with the times.

For the 12s I load Smarty # 8, switch TST to 03tt and advance timing to 15* and set EZ to level 3. I do normally remove my tool boxes from bed, leave the spare at home and try to remember not to fill up. That's about it, takes about 10 minutes to load the Smarty, make the other setting changes and go to staging lane.
 
At your power level weight is about 200lb per 0.1 seconds.

If you are 2wd, slicks are a huge improvement in ET, but lose MPH.
 
I ran slicks a couple of time this year, and I liked them :D
Other than that I removed the tail gate and cleaned the travel "stuff" out of the bed. Comp shared some suspension and airflow info with me yesterday, I've definately got some more power to build into the engine but I suspect that I will also need to find some tricks in order to get into the 12s. At 200#=0.1 sec it doesn't look like dropping the easy weight is going to gain much advantage.
 
How about a lightweight tonneau cover? what if you chained the front suspension down?


Not to take away from your post Bill but Ive attached a pic at IRP with SLICKS!! What a sight to see a 13s truck turn around and tow a camper full of supplies and passengers the long haul home!!

Ian
 

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I thik 1-2 more Comp D stickers will put you solidly in the 12's Bill LOL
 
i have a friend with a 2wd 24v and he put caltracks on and they kick butt, droping the weight won't help alot but every bit counts, suspension set up helps, i would get a set of acaltracks and play with em
other than that MORE POWER lol lol
robert
 
I bolt on the slicks, pull the headlight and make sure the bottle is full. Flip the DSP2 switch to race and we are good to go.

Everything else stays ready on my rig in regular running fashion.
 
Timbeaux38 said:
I thik 1-2 more Comp D stickers will put you solidly in the 12's Bill LOL
Click to expand...

ahhh, but where do I place them to achieve maximum aero-advantage??? :ylsuper:
btw, good eye Tim!!

Thanks Ian!! I hope pics of my truck don't take away from a thread :doh:

Remember only a few years ago when a daily driven/camper haul'n/race truck got a chuckle out of the high performance crowd, everybody's dream so to speak??? I know there are few people doing it these days. Good friends willing to pull the camper and trailer the truck home are a beautiful thing. :bow:

I hadn't thought about chaining down the front end, maybe we should try that after the Hooters meet next month LOL

Seriously though...
Comp also suggested CalTracks and removing some leafs as well, while using airbags and adjusting the Caltracks when I need to haul. Seems like the airbags would work for street driving and camper hauling, that is essentially what a Kelderman is doing, right? I don't mean to compare the two as I am sure the Kelderman setup is well advanced of what I am talking about. My reference is to using airbags instead of (more or less) leaf springs. I do have bars but they don't pivot like the CalTracks do.
 
My main prep when I get to the track, is to make sure there aren't any drinks in the drink holder... :bang Turning the cell phone off is a good idea too. A call at the wrong time, has been known to cause "premature acceleration".

Seriously. I air down the tires, and install spring clamps on the front of the rear leaf springs. Set the comp box on the desired setting and turn on the RAD.

Paul
 
paulb said:
Seriously. I air down the tires, and install spring clamps on the front of the rear leaf springs. Set the comp box on the desired setting and turn on the RAD.

Paul
Click to expand...

thats what i do except i was told to clamp the rear of the back springs:confused:. Was i told wrong or does it work well both ways?
 
lukecline said:
thats what i do except i was told to clamp the rear of the back springs:confused:. Was i told wrong or does it work well both ways?
Click to expand...

You want to clamp the front of the spring pack to control axle wrap and to emulate having a set of traction bars on the truck.
 
Clamp just the back of the leaf packs if you want to reduce axle wrap / hop. Think of which way the tires are trying twist the rear axle. Opposite of rotation, or CCW looking from the passenger side. The front of the leafs are going to "pack" themselves under torque, but the rear leafs with try to separate.

Clamping the front will not affect anything but increase spring rate, which often hurts.
 
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McRat said:
Clamp just the back of the leaf packs if you want to reduce axle wrap / hop. Think of which way the tires are trying twist the rear axle. Opposite of rotation, or CCW looking from the passenger side. The front of the leafs are going to "pack" themselves under torque, but the rear leafs with try to separate.

Clamping the front will not affect anything but increase spring rate, which often hurts.
Click to expand...


I respectfully disagree. You want zero axle wrap on a launch. The forces involved with axle wrap attack the front of the pack first.

soa3.gif


The rear of the pack retains its natural shape and strength. The front goes into an "S". Every article on drag racing with leaf springs or off-roading addresses the front of the pack.

My Cal-Tracks address the front of the pack. As far as increasing spring rate hurting, that is directly contrary to one of the two methods for controlling axle wrap - increasing spring rate/strength or adding traction bars. Addressing the front of the pack is the only way to limit pinion angle changes IMHO. If you are trying to emulate having a solid link on the front of your suspension clamping the front of the pack is the only way to address this. Hitting the back won't do diddly in that respect.

This image shows what a traction bar is doing pretty much with respect to the front of the pack:

soa12.gif


Here are a few other blurbs:

Wrap-up - Referred to as both rear spring and rear axle wrap-up. As power is applied, torque load causes the rear pinion to pivot upward. Once this load reaches a certain point the leaf springs begin to deform, which stresses numerous driveline components. The "fix" is to increase spring strength, via add-a-leafs, or install traction bars.

http://www.4x4wire.com/jeep/tech/susp/axlewrap/

I can't find anywhere where folks are clamping the back. I wonder if we called Lakewood tech support on their kit where they would recommend clamping the pack? I bet ya a dollar they say the front. ;)

Anyone else think the rear is the way to go?
 
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If I'm not feeling lazy, I'll pull the spare, hitch, back seat, and battery. Air down the tires, lower the t-bars(4x4), clamp the front of the rear springs, and adjust cal-tracs. That's the max amount of prep for me.
 
The bars on my truck attach to the axle u-bolts from the bottom side and bolt to the frame on the front. They seem similar to the caltrac except for the front pivot. What is the advantage of the pivoting?
 
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It allows dynamic loads to be applied to the front of the spring pack to cause the shift of the instant center, giving more weight transfer and better downforce grip on the tires.
 
Thank you, I hate to admit it, but I had to read this numerous times and check back to the CalTracs web site before I could visualize the concept.
 
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