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Re: How to race on a poor track with drag radials [Re: Kam*Kuda] #3065820
08/06/22 03:59 PM
08/06/22 03:59 PM
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A shed in England
Tig Online content
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A shed in England
Do a search on Yellow Bullet, lot's of info on this subject.


'74 Challenger..9.46 and 145.9 so far. 4023lb!!!# N/A, Marsh performance 655ci, Indy Maxx, T/R, Indy 600-13 X's, Street legal, pump gas, full interior, Cal-Tracs, mufflers, 3:73's and real 10.5 radials.
9.51 @142.4 with our old mule 580 wedge
RHD '68 Barracuda Fastback 323ci street/strip. Best ET 13.88 @ 99.03
Re: How to race on a poor track with drag radials [Re: Kam*Kuda] #3065821
08/06/22 04:01 PM
08/06/22 04:01 PM
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Canada
Kam*Kuda Offline OP
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FYI 3.54 gears in a Detroit locker

Fairly tight converter

32 inch ladder bars


1970 Barracuda Convertible
1968 Satellite Street Strip car
1654.5 Mustang
1955 Land Rover
Re: How to race on a poor track with drag radials [Re: Kam*Kuda] #3065833
08/06/22 05:09 PM
08/06/22 05:09 PM
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Wichita
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GY3 Offline
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Street racing..

20180517_084059.jpg

'63 Dodge 330
11.19 @ 121 mph
Pump gas, n/a, through the mufflers on street tires with 3.54's. 3,600 lbs.
10.01 @ 133mph with a 250 shot of nitrous an a splash of race gas. 1.36 60 ft. 3,700 lbs.

Re: How to race on a poor track with drag radials [Re: GY3] #3065834
08/06/22 05:11 PM
08/06/22 05:11 PM
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On the parachute mount
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n20mstr Offline
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On the parachute mount
3.54 rear , should go right down

Read my post earlier ,please


....BAD A$$ STREET CAR.....
Re: How to race on a poor track with drag radials [Re: n20mstr] #3065840
08/06/22 05:32 PM
08/06/22 05:32 PM
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Canada
Kam*Kuda Offline OP
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Originally Posted by n20mstr
3.54 rear , should go right down

Read my post earlier ,please


Thanks I will absolutely try your suggestions. that car is moving.


1970 Barracuda Convertible
1968 Satellite Street Strip car
1654.5 Mustang
1955 Land Rover
Re: How to race on a poor track with drag radials [Re: n20mstr] #3065846
08/06/22 05:57 PM
08/06/22 05:57 PM
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Wichita
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GY3 Offline
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Originally Posted by n20mstr
3.54 rear , should go right down

Read my post earlier ,please


That's what we run


'63 Dodge 330
11.19 @ 121 mph
Pump gas, n/a, through the mufflers on street tires with 3.54's. 3,600 lbs.
10.01 @ 133mph with a 250 shot of nitrous an a splash of race gas. 1.36 60 ft. 3,700 lbs.

Re: How to race on a poor track with drag radials [Re: GY3] #3065935
08/06/22 10:53 PM
08/06/22 10:53 PM
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I say upper hole on ladder bars, reset pinion angle, and set the shocks up with looser extension and stiffer compression to hold the extra hit you are putting on the suspension.

I just redone my car this week because I was having trouble on the bad track with slicks. Upped the Antisquat to 110 percent and it worked. Car was great today.


67 Barracuda street/bracket car 11.27-119
68 Dart 502 BB 8.70s-152
414 cid SB Dragster 7.65-174
Re: How to race on a poor track with drag radials [Re: Kam*Kuda] #3065975
08/07/22 08:08 AM
08/07/22 08:08 AM
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MI, usa
dvw Offline
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I'm looking at your shock picture. What is the travel of your shock? On a radial you want the shock compressed at least 60% at ride height. When light springs are installed they will need to be compressed. The platform will end up being screwed way up to maintain the current ride height. Can't see from this pic. Is there a height adjustment where the shock bolts to the lower mount? Also agree it may be tough without double adjustable shocks. also agree that the bars may have to point upward.
Doug

Last edited by dvw; 08/07/22 08:14 AM.
Re: How to race on a poor track with drag radials [Re: dvw] #3066001
08/07/22 10:04 AM
08/07/22 10:04 AM
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Oakland, MI
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Sorry for the long post, but hopefully this is helpful for those that take time to read it.


Couple of ideas.

1) As mentioned it needs a spring change as what you're running is really stiff.

2) Most Radials are run at much higher tire pressure. 15psi is really low. I run 18.5PSI on my 275 Pro Radials.

3) The front and rear shock settings are key to making it work. In the rear you need to balance having the shock loose enough to initially "hit" or plant the tire, but not so loose that it runs out of travel. For the front, you need to make it loose enough that you're allowing the body to move and waste some energy that you don't have traction for, but not so loose that it runs out of travel quickly and unloads the tire too hard.

It's a balancing act for sure. The radials are not very forgiving... once they spin... they spin HARD. A regular bias ply can spin but still recover and get the car moving.




This is a video I made quite a while ago when I was working to get my car to leave on the radials. https://www.youtube.com/watch?v=jr1VILyS7WE

Run #2 is an example of the shocks being too loose, the car hits the tire hard and runs out of travel quickly and spins the tire about 1/8 of a tire rotation (watch the valve stem).

Run #4 has tighter rear extension on the shocks, hits the tire and you can see the slower separation allows the tire to turn a LOT further before spinning. This setup ALMOST worked.

Run #5 is an example of the rear extension on the shock being too tight. You can see that it does not hit the tire hard enough, and spins almost right away because the tire doesn't get planted and the body doesn't separate.


(Note that the 16psi shown in the comments at the top of the video's are PSI of turbo boost, not tire pressure. All tire pressure was at 18.5)




Not to complicate things further, but ultimately the settings from run #4 above got me to reliable 1.37~1.41 60ft times EVERYWHERE I ran the car. The rear setting from run #4 allowed the rear tire "hit" to plant the tire nicely, and the shock was set as a nice smooth body separation. Ultimately TIGHTENING the front shocks from 10 clicks down to 6 made this setup really really reliable. If you watch run #4 towards the end of the video when you can see the whole car, you can see the rears spin at the moment the front suspension runs out of travel. By delaying that front from running out of travel with tighter front shock settings, the rear would stay planted, get the car moving, and ultimately 60ft reliably.


I know that's a lot to digest, but take some time and watch the video's, read the comments above, and it should get you pointed in the right direction.

Re: How to race on a poor track with drag radials [Re: dizuster] #3066023
08/07/22 11:40 AM
08/07/22 11:40 AM
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Canada
Kam*Kuda Offline OP
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Thank you all! This experience is very helpful.


The shocks are positioned at the lowest setting. I have double adjustable afco in the front.


The plan moving forward...


1. I will set the ladder bar front to the upper setting


2 . I will increase air pressure to 18-20lbs and trial it. Should I start at 20 and work down or 18 and work up in pressure?


3 I will get what is available but I believe my options are 110 lb and 130 lb springs. Available in 12 and 10 inch. Where would you start?


4. Shock setting (I got some learning to do LOL) Would happily look at any suggestionsfor a double ajustable here





Last edited by Kam*Kuda; 08/07/22 11:44 AM.

1970 Barracuda Convertible
1968 Satellite Street Strip car
1654.5 Mustang
1955 Land Rover
Re: How to race on a poor track with drag radials [Re: Kam*Kuda] #3066052
08/07/22 02:24 PM
08/07/22 02:24 PM
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MI, usa
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Spring length is dependent on how much shock travel you have If it is 5" or more the 12" would be my choice. My car actually runs 11"springs. They are a barrel shaped oval track spring. You can see how far up the spring platform gets with a short spring. This car weighs aprox 1500lbs on the rear with about 310lbs of that being unsprung. Springs are 122lb.
Doug

20210329_160439.jpg
Last edited by dvw; 08/07/22 02:29 PM.
Re: How to race on a poor track with drag radials [Re: dvw] #3066093
08/07/22 05:44 PM
08/07/22 05:44 PM
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im not sure that having slight wrinkle is a big problem . I know iwill see some intermittantly on my Satellite . I run 19 - 19 1/4psi in my PBR 29.5x10.5 . I feel the wrinkle is more often a sign of hook than psi especially if you are above 18psi to start with . This is both foot and trans brake though more obvious wth tbrake . The PBR is probably the most forgiving radial , i find it "walks "out mostly rather than spins , chirps/ scrabbles if it doesnt hook then picks up and keeps going . That said i have had a couple passes where they flat spun but not too common for me .
As to suspension setup , cant help as i am leaf spring Caltrac and a little nose heavy with a World iron block .

Tex


New best ET 10.259@129.65 .
New best MPH 130.32
Finally fitted a solid cam,
stepped it up a bit more
3690lbs through the mufflers
New World block 3780lbs 10.278@130.80 . Wowser 10.253@130.24 footbraking from 1500rpm
Power by Tex's Automotive
Re: How to race on a poor track with drag radials [Re: tex013] #3066139
08/07/22 10:51 PM
08/07/22 10:51 PM
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A shed in England
Tig Online content
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We still get a slight wrinkle using the M/T Pro Drag Radial, we've been as high as 22psi (warm) and still seen it, As above car is on Caltracs and Leafs.
[Linked Image]


'74 Challenger..9.46 and 145.9 so far. 4023lb!!!# N/A, Marsh performance 655ci, Indy Maxx, T/R, Indy 600-13 X's, Street legal, pump gas, full interior, Cal-Tracs, mufflers, 3:73's and real 10.5 radials.
9.51 @142.4 with our old mule 580 wedge
RHD '68 Barracuda Fastback 323ci street/strip. Best ET 13.88 @ 99.03
Re: How to race on a poor track with drag radials [Re: Tig] #3069685
08/19/22 08:04 PM
08/19/22 08:04 PM
Joined: May 2003
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Cleveland Ohio
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Everything the above racers said, plus seat time. The more you race better you will get. Glad to see you out racing that RR. Now lets get Ron in the Charger Back Out

Re: How to race on a poor track with drag radials [Re: Kam*Kuda] #3069733
08/19/22 10:16 PM
08/19/22 10:16 PM
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Missouri
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Not to hijack the thread, but NSS has to run 10.5 tires and I have messed with 4-links for a long time, and I can get it to hook on just about any track, on the starting line, but since the last engine rebuild it makes enough torque that on a slick track it wants to break the tires loose on the big end of the track. I watch the drag radials, and no prep guys and wonder as well what they do to get those cars to hook. I would not mind trying a no prep car, but it looks to me like it is not if you will wreck a car but when. So I am all ears to getting a car to hook down track.

Last edited by jwb123; 08/19/22 10:17 PM.
Re: How to race on a poor track with drag radials [Re: Kam*Kuda] #3069737
08/19/22 10:39 PM
08/19/22 10:39 PM
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Racine, Wisconsin
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Originally Posted by Kam*Kuda
Fairly new driver... I am learning and trying to get consistent...I am not experienced...



You own a mid 9 second car.. that is really fast, regardless of what the internet says... one important question: Have you ever driven a car with bias ply slicks at low air pressure before? They hook amazingly well compared to drag radials, but they have very different feeling at high speed. I am far from an expert, but my low 10 second car hooked very well with 28x10.5 bias ply at 12 psi on test and tune tracks... but made me a bit nervous at 140 mph... when I tried 325/50R15 drag radials it felt like cruising on the highway with one hand on the wheel at 140... but did not hook well at all... just my 2 cents...

Re: How to race on a poor track with drag radials [Re: Craig J] #3069764
08/20/22 02:00 AM
08/20/22 02:00 AM
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Bend,OR USA
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One thing to remember when letting off on cars with bias tires that start to wiggle at low pressure, the back of the car has to follow the front when coasting, don't overreact try and correct it when it is sashing, it should slow down enough to not wiggle after 3 to 5 seconds twocents scope up


Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
Re: How to race on a poor track with drag radials [Re: Craig J] #3070494
08/22/22 03:15 PM
08/22/22 03:15 PM
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Canada
Kam*Kuda Offline OP
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Originally Posted by Craig J
Originally Posted by Kam*Kuda
Fairly new driver... I am learning and trying to get consistent...I am not experienced...



You own a mid 9 second car.. that is really fast, regardless of what the internet says... one important question: Have you ever driven a car with bias ply slicks at low air pressure before? They hook amazingly well compared to drag radials, but they have very different feeling at high speed. I am far from an expert, but my low 10 second car hooked very well with 28x10.5 bias ply at 12 psi on test and tune tracks... but made me a bit nervous at 140 mph... when I tried 325/50R15 drag radials it felt like cruising on the highway with one hand on the wheel at 140... but did not hook well at all... just my 2 cents...





Thanks... I drove a 12 second car with slicks and it did wag at the top end. What you said is why I originally didn't want slicks as it the wag would make me nervous.
'


1970 Barracuda Convertible
1968 Satellite Street Strip car
1654.5 Mustang
1955 Land Rover
Re: How to race on a poor track with drag radials [Re: n20mstr] #3070504
08/22/22 04:05 PM
08/22/22 04:05 PM
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Originally Posted by n20mstr
This car runs 9.30s at 140 , any track anywhere. It’s on a 295 radial

What you need is probably a 110 or 95 rear spring . Ladder bars level or 1 or 2* up , and you need a double adjustable shock with at least 4” of travel . Loose on extension, somewhat firm or stiff on rebound . You want to smash the tire and keep it smashed , don’t let it bounce back . Front may need to be more travel and somewhat tight on extension, you want a controlled rise in the front .

The nova runs a 2.10 first with a 3.70 rear
Not sure what your rear gear is but yes a little less SLR can help

Some may not agree , but I think I have some experience with radials whistling


"This"......especially "quality valved" DA shocks, more seat time, and tune for the below average track conditions. There is no separation, needs more extension, slow down the front a bit, and squash the tire more to keep it planted. Only foot-braking, no transbrake? Lastly, you could always work harder with what you currently have if your budget is tight by making cost effective changes. You have more than enough tire, and the gear is no problem.


"Any fool can know. The point is to understand"

- A. Einstein
Re: How to race on a poor track with drag radials [Re: EvilB1Dart] #3070635
08/22/22 10:43 PM
08/22/22 10:43 PM
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Canada
Kam*Kuda Offline OP
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I have the ability to fit a shock with a 5 inch extension.
A friend suggested i change the setup for atleast 7 inch extension. This will be a pile of work

Would a 5 inch extension be sufficient or would it be worth the work for the extra 2 inches (40% more extension)


1970 Barracuda Convertible
1968 Satellite Street Strip car
1654.5 Mustang
1955 Land Rover
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