I am planning to run a local Mopar race that is for street cars and does not allow slicks for the bracket race. I have tried radials years ago with not much luck hooking consistently, it would hook one pass and then blow the tires off the next. I normally race with a 29.5 x 10.5 MT bias slick, but wanting to run on my street tires 295/65/15 ET Street S/S. With slick and old motor the car has been 1.43 60' time. Current motor is a 5.7 with supercharger and is lazy in the 60' (1.5649 best 60', 6.6206 1/8 mile at 106.11 mph, 10.3120 1/4" mile at 132.70 mph)

The car is a 73 Challenger about 3650 lbs
Calvert mono leaf springs and bars, Strange double adjustable rear, and Calvert 90/10 front
4600 converter with 4.10 gear

I am looking for a good starting point on tire pressure and rear shock settings. Any help is greatly appreciated.

My sons car will literally 60' 1.40's anywhere . Its caltracs with a 295 radial. He has Afco double adj out back and the calvert 90/10 up front. We run the Afcos full tight on the extension and almost full tight on the compression. Now we are a nitrous car, with no progressive or launch retard, we literally spray a plate .
Im not sure about the front segment of an E body Spring , as an A body spring is short and really slams the tire We just got the Afcos revalved to a "radial" valving. I would say with the radial tight is better, now if it doesnt hook, loosen the extension a little at a time. You want the car to plant the tire and hold it there. Pressure on a radial is usually higher than a slick. You dont want to wrinkle the tire because it will snap back and tire shake. We run the 295 at 20lbs, sometimes as much as 22. Even on my Ultra street car, we run the tire 17.5 to 19 depend on track. Rim size also effects the tire pressure. A wider rim needs more air to keep the tire from cupping in the center.

Every car will be different but we run 18 psi in our drag radials. Shock settings with the Calvert/Rancho's was always full stiff @ #9. Fronts at 90/10. Best of 1.36 60 ft.

With Vikings running N/A we are doing 12 Compression and 6 Rebound on the rear. Not much of a chance to test with the Vikings with nitrous but it is doing a wheelie and then unloading and spinning with them. Going to try going to the 70/30 to slow down the extension. Ultimately it needs Vikings on the front, too.

^^^^^ THIS , When you get to the point your at (10.30's high 9's) You going to need a double adj front to slow the front extension. That and the HP to move a 3600lb and radials dictate a GOOD double adj rear shock. YOu be surprised how hard it is to pull a radial valved shock apart LOL But its whats needed to control the tire. Especially on Mopars that have short front spring segments and that translates to short instant centers that slam the tire. Thats why shock valving that works on GM leaf spring cars is still too loose for a Mopar. They have different length springs and different Instant Centers

We have 20" front segment monoleafs on our Challenger (using the old S/S spring mounts) and as stated, it does hit the tyre hard. We had our rear D/A Afco's re-valved by Menscer to control it. Without looking at our settings book, I'm pretty sure we are close, 6 or so clicks from full tightness on extension but it works well. We have Santhuffs on the front. We are running a radial slick 29.5 x 10.5 between 19 / 21 psi. car weighs over 4000lb and we regularly 60ft with the backs around 1.38 with a 1.36 best. A couple of years we were putting them down before the 60 beam with a best of 1.34. 4.10 rear (though we are changing to 3.73) 5500 stall, 51.5% over the rear.

I run Viking dbls out back , the radial valved units . QA1 singles on front , yeah i should get dbls but i rarely have traction issues . Caltracs and Mopar XHD springs .
#10 from compression / #5 ext rear . Full loose front .
When i ran 275s (8"rim)or PBR 28s i was 18-18.5psi
Now with PBRs 29.5x10.5 on 10"rim its 19 1/4
Hoosier Radial 30x10.5 on 8"its 18
High 1.40s leaving @ 1500
Currently footbraking , but also have used transbrake .
The best shock you can afford is your friend on radials , especially rear .


Tex

Hey, long time no chat! Hope all is well! Where is the race and what details! Would love to bring my truck out to it!

My Dart is 3350 and has been 6.25 @ 110 in the 1/8 on a 325 radial. It now has a 275 and has been 6.28. It has Viking double adjustables all around, 2C/10R on the rear and 16C/18R on the fronts on marginal tracks, all from full loose. The fronts have been revalved for no prep surfaces as I run mostly street car shoot out stuff. On well prepped tracks I lock the front shocks down, full tight.

Thanks for the information, this will be a good start and hopefully it hooks okay.

James- It will mostly be new Challengers and Chargers. I'm not sure if it would be worth the drive from Houston, but if you are in the area it should be fun. They also have a meet and greet with free bbq on Friday. I wish we still had a big Mopar race in Houston or Ennis, but there's nothing in the area.



Saturday September 25th at Alamo City Motorplex from 12-7pm. Gates open at 10am.

THIS PAGE PERTAINS TO THE DIAL-IN BRACKET CHALLENGE SEGMENT OF DJAC FALL FEST ONLY .

DESIGNED FOR ALL STREET-LEGAL MOPARS !!

NO SLICKS......NO NITROUS

ALL DRIVERS WILL BE CLASSED INTO 4 DIFFERENT GROUPS BASED ON THEIR LOWEST PREDICTED 1/4 MILE TIMES:

GROUP A: 13 seconds & UP

GROUP B: 12 TO 12.99 seconds

GROUP C: 11 TO 11.99 seconds

GROUP D: 10.99 seconds & UNDER

i would look at and buy the same size ET Street Bias ply as the slicks you mentioned
Are the tires you mention,295/65/15, radials or bias ply?
I ran the M/T ET Street 325x60x15 ET Street Radials and the same size ET Street bias ply and the radials were faster on a good track but not worth a hoot on fair or bad track or on fair street
Once the radials would start to spin I had to let off for them to recover
The same size ET Streets might spin a 1/4 to 3/4 turn on the hit but hook and stay hooked up after that on bad streets and roads
I ran both 10 and 12 inch wide rims and used 18 to 20 lbs. on the radials and from 9.0 to 12.0 on the bias ply tires depending on the track conditions to get them hooked up and stay hooked up
I ran both tubeless also

That is next weekend. Not sure I would be able to get the truck ready by then! I haven't taken it down the track in about 5 years. Sold it and bought it back about 2 years ago. I just did some suspension work, scaled it and bought new DRs. But haven't been down the track yet.

Good luck!

CAB- The tires I run are radials. I ran the bias ply ET Streets for a bunch of years and they do work great. I am driving the car a lot on the street now (about 3000 miles the last year), so I really wanted a radial. This event is just a fun street event and if I am normally bracket racing I put the slicks back on.

TOD- I forgot there is a Mopar event at Houston Raceway Park on Oct 9th, Lonestar Mopar Fest. Again this is for new LX cars and hemi powered cars, but I think they have an open test and tune session. I am planning to make it out to this event.

http://lsmfest.com/

I may be able to make that!!! Let's meet up if I do. Been at least 25 years right?

So how did you do??

The event is this Saturday 25th. Hopefully I can hook on radials..

Ah ok... As for the radials, hit the tire as hard as you can. If you have rear double adjustables (which you really need for radials), if the track is decent, set both pretty stiff.