Went to the track today in full street trim.No weight reduction on 20 inch street tires and 2 wheel drive.First run I tried to feather the throttle about 1/2 way and got some wheel spin but hooked enough to mash it about 100 foot out

1st run

60'...2.23
1/8...8.79@83.21 mph
1/4...13.60@100.84

Picked up ticket and was told I could not run again without helmet.
Borrowed a helmet later that day.Lined up against my buddy in his SRT8 HEMI that was running 13.5. Well I figured I would try to leave a little harder than before and when the yellow lights came on my dumbass leaned on the converter and mashed it to the floor like I had slicks(big mistake).This resulted in massive tire spin in to 2nd gear,gained traction which resulted in tranny down shifting into 1st again.Needless to say I lost with a 2.6 60' and 14.23 1/4
All this was done on my stock original transmission with plenty of torque management still in it to make it live.Boost goes to 0 when shifting as the Electronic throttle body closes during shift.Had to leave after that but felt OK for 1st time out in 2WD with 20" street tires no deflation.

 

How do you think you would have fared in the traction department with stock 275ish tires? Those monsters had to have helped out at least a little bit.

 

I had 12" wide rear tires before and it was joke.I could stomp at a 30 roll and pull sideways as it shifted to 2nd gear and would spin till about 70.Big tires made a big difference.I think if I let the air down to 20PSI or so I could achieve low 13's on street tires with some practice track time.

 

With that much tire you shouldn't have any traction problems unless those tires are just that crappy. Do you have any suspension mods yet? Hell, I just ran my 13.59@100 on my almost 6 year old Hankook's (275/45R20) with no tire spin. Granted you make more torque, but something's not clicking there. With that big of a tire you should be at 18-22psi even with a radial just because the tire is so big. Were you doing a burnout?

 

Tires were at about 28 PSI .I have never checked my pinion angle since lowering 4" in rear which I am sure has a lot to do with it.Tires are Mickey Thompson SSR radials.No real burnout just enough to get left over water from other people tires off.This is also an extended cab truck weighing about 500 more lbs more than a RC. Like I said in 1st post I need more practice trying to launch with 400 ft #'s of torque.

 

I can see what you're saying. I've driven quite a few trucks like yours with 400+ftlbs and even way more than that and on the street they can be a handfull. At the track though you really shouldn't have any traction problems. Pinion angle and tire pressure could certainly be an issue. Why no burnout though?

 

There is a such thing as to much contact patch, will result in not being able to plant the tires and keep the hooked..

 

I will try a burnout next time,You get plenty of opions from people mostly saying heating up street tires is worthless.Since it was 1st time out I wanted to see what it would do completely street trim as if racing from a redlight.This is mostly a show truck that I take out the garage once a month on a Sunday drive.So big difference in pedal control after driving my other 2 stock trucks.I saw a thread the other day someone was trying to figure out the correct way to measure pinion angle.How low is the safest air pressure on street tires?

 

I've discussed the no burnout on street tires thing many times over. Street tires will get sticky with a burnout, but will quickly get greasy with too much burnout. You just have to do a burnout that works well with your tires. With my truck for example if I do no burnout it just does the burnout for me at the line. There is an art to a burnout on street tires and getting good results. The thing is the tires you have should be more suited to track use. I would run them down to 22psi and do a mild burnout. Make sure you go around the water though so you don't track water to the line with the fronts. What I recomend is to go around the water and then back into it. When the guy tells you to light'm up, pull out of the water before doing your burnout. Don't do the burnout in the water with street tires since the tread will spray water all over the back of the truck and up into the wheel well which can drip water on them when you are staging. Roll it forward, spin them through first, shift second about 5500, and release the brakes giving it enough throttle to keep them spinning in second without laying down for about 5-10 feet. This should all only take about 5 seconds between when they start spinning and when you are ready to let up. I've ran my personal vehicles and more than a hundred others for people/customers on street tires so I'm certainly not new to it. Make sure the pinion angle is correct also and you should have good results. Since the truck is a show truck, use saran wrap or that blue body shop masking tape on the back of the truck to keep the rubber from sticking to it. With the power you make you want to enjoy it all and get it all to the ground.


btw, love that avatar.

 

Now that's some advice I like to hear from someone with plenty of experience.Thanks and I will try that out next time.