Hi All.
I'm racing in a week or so and going to try out some M/T pro drag radials 3062R's. Car is a 3940lb race weight Challenger, which has been 1.36 60ft but we seem to be struggling at the moment with the Bias plys, not sure if the sidewalls are gone
I need some tips, do's and don'ts etc. We're total newbs when it it comes to Radials
Front suspension is stock(ish) type with .870" T/B's, heim jointed struts, QA1 heim jointed UCA's and stock bushed QA1 LCA's with D/A Afco's and Menscer valving. Rear is Caltracs with Monoleafs, shackles, A/R bar, again with Menscer valved Afco D/A's. 4:10 Dana stock 727 ratios. 572 puts out around 850 HP
OH I'll be taking my old Bias plys with me just in case.
TIA

you are in for a treat !

you are faster than me and 200lbs heavier .
I run the PBR 29.5 ( 30" tall) @ 19psi on a 10" rim
Decent burnout , I like to see good smoke maybe 5 seconds or so , too little tyre will not hook fully
Tyre pressure up till spins , probably start at 18 .Rear shock - towards loose extension / tight comp . I run Viking rears 10 comp 5 ext , QA1 singles up front full loose . I have no AR bar .
A mate in his 4000lb 62 chev on the PBR 29.5 runs 18.5-20 on a 8" rim
Good luck . I have found the PBR is quite forgiving , it wont blow the tyre off just chirp or a partial turn then hooks

Tex

Did Mark valve the shocks for radials or bias?

If they were valved for a bias slick I'd give him a call to see where the settings need to be to work (if they'll work at all...)

Good point, I was unaware that they would be valved differently. They where done some time ago, I can remember that I spoke to Craig and that I would eventually be trying Radials, but would continue to use Bias plys for the time being as I just had some new. Don't recall anything coming up in conversation that I would need to change stuff.
Could this be why I'm not 60fting like I did previous to the shocks being re-valved but I have made many other changes also??? The reason for re-valving was we ran out of extension damping.

Yeah the Radials and Bias will most definately have different valving.

That being said... there MIGHT be enough adjustment in a bias valving to use on a radial, just depends on how they were set up.

Worth a call to Mark or Craig... they'll set you straight.

It's HUGELY benificial to get some slow motion side video of the car launching. I've sent that kind of stuff to Mencer before and had him help tune from the vids.

What should side walls look like at launch when properly inflated? Wrinkles or no wrinkles? Reason for asking, I just got new MT Pro Bracket Radials, 14x32x15. Data logger shows a little spin at launch & gear change.

I would try the set up you have & go from there. More tire pressure than a slick & the shortest burnout possible to just get them to start to smoke. They also do not recover like a slick does with a slight pedal job to get them to recover. You have to gradually get back into the pedal & reload the suspension & get the weight distributed again or abort the run. Try again next time

They work

Just a quick update now I have a decent internet connection. We did indeed start out from where we left off settings wise but since we had issues with the bias plys we had the front shocks and travel set to weight transfer quick and the rear to hit the tire less than we usually do. 1st pass was a 1.38 60ft with the fronts touching just after the 60ft but not high enough to be out of the beams. Looks like we PB'd to the 1/8th (with the 572 motor) in MPH and ET. Unfortunately the car in the other lane had a bad missfire, I thought I was on the rev limiter and lifted at around 1100ft so we could have been on for a 9.5.
We left everything as is for the next pass but we were now happy to "go for it" after getting the first pass out of the way and everything checking OK on return. This time though, it came up really fast and high, instinct took over and I made the error of lifting. The resultant crash landing about 100ft out squashed the pan and caused some minor breakages so we had to call it quits for that meeting.
Have to say they do work but next time out we will be looking to calm it down some
Thanks for all your reply's

Great looking car. Congrats on the pic. That's a good one

Tig, how come you have the "little" motor back in??
Mike

Wanted to do some upgrades on the 655, then the car went to the paint shop for over 12 months, came back and I prepped and painted the trunk, shuts, engine bay and underneath for another 6 months. We also re-wired it and fitted loads of new suspension parts. The 572 went back in for a couple of meetings (we thought) but since we struggled with traction and bogging issues with the tunnel ram so it stayed in 'till we fixed all that. Now the 572 is staying in 'till we calm it down
We're hoping to run 8's N/A on the 655 when all is done