Tuesday May 29th. Installing race shocks. Question about the rear shocks setting.

[biomedtechguy]

I apologize for the late question, but I am installing the 3 way adjustable CEE-2730 Competition Engineering rear shocks on my 70 Roadrunner tomorrow. Since they have to be removed to be adjusted, I would like suggestions on what setting to start at? I will have the Viking double adjustable 2 dial shocks on the front, and I can adjust them anytime. I figured I'd go 90/10 on the fronts at the track.
What setting to start with on the rears?
50/50 is my guess...
"The ratios for the rear shocks are 70/30, 60/40, and 50/50. These numbers represent the percentage of force required to extend (first number) and compress (second number) the shock."
Stock 440+6 Roadrunner rear leafs. Stock front suspension except for the Viking shocks. 315/35/17 Toyo Proxes TQ drag radials on 17" aluminum Rallye wheels. Standard transmission. 4:10 R&P
The adjustable pinion snubber is going on my Dana 60 tomorrow also.
Test and Tune night is Wednesday.
Thanks!

 

[elevensies]

depends upon how good or bad your springs are, depends on how you have set your pinion snubber, and depends on how much front end you have to lift, and then depends on track prep for first 60'
so as your running stock springs, are they clamped on the front section, and have you removed the clamps on the rear?
the snubber needs to be 1/4'' from the floorpan
the front end needs to be around 1/2" to 3/4" off bumpstops
as your on stock springs id be as loose as possible so they can let the rear rise quickly then settle after launch, you will hopefully get lots of leaf separation on the rear section, and no wrapping on front.

hope this helps

 

[dvw]

Manual trans is tough with radials. Snubber close to the pan helped my 4 speed car. You need to hit them hard with rebound (loose) and keep them there with compression (tight). But with a tight clutch it'll hit them hard anyway. On yours I's start tight. On the front many times we see that 90/10 is too loose as the the front end comes up immediately, tops out and unloads the rear tire.
Doug

 

[biomedtechguy]

are they clamped on the front section, and have you removed the clamps on the rear?

I haven't done anything with them, but I will look for those mods. Chances are they are exactly like they come from the factory.

depends on how you have set your pinion snubber

Going to set it as recommended by forum members.

depends on how much front end you have to lift

440+6 aluminum intake and headers, no power accessories, factory front sway bar.

the front end needs to be around 1/2" to 3/4" off bumpstops

I will adjust the torsion bars accordingly.

Manual trans is tough with radials. Snubber close to the pan helped my 4 speed car. You need to hit them hard with rebound (loose) and keep them there with compression (tight). But with a tight clutch it'll hit them hard anyway. On yours I's start tight. On the front many times we see that 90/10 is too loose as the the front end comes up immediately, tops out and unloads the rear tire.
Doug

How does that translate to REAR shock settings when I install them? I can change the front settings anytime.
Rear choices are:
"The ratios for the rear shocks are 70/30, 60/40, and 50/50. These numbers represent the percentage of force required to extend (first number) and compress (second number) the shock."
Thanks!

 

[dvw]

I haven't done anything with them, but I will look for those mods. Chances are they are exactly like they come from the factory.

Going to set it as recommended by forum members.

440+6 aluminum intake and headers, no power accessories, factory front sway bar.

I will adjust the torsion bars accordingly.

How does that translate to REAR shock settings when I install them? I can change the front settings anytime.
Rear choices are:
"The ratios for the rear shocks are 70/30, 60/40, and 50/50. These numbers represent the percentage of force required to extend (first number) and compress (second number) the shock."
Thanks!

I'd start50/50
Doug

 

[elevensies]

ahh sorry i didn't see your a manual trans, kinda changes a coupe of things as dvw says.
manual hits the tires hard, so you need gradual lift, so 50/50 is a good starting point
your front sway bar is also a limiter too, racers dont use them.
you will be fine, just start in the middle for everything inc the fronts and work from there.

 

[biomedtechguy]

Front Viking shocks sure are purrty...

 

[biomedtechguy]

Set the fronts for the 5 mile ride home to 7 and 3...very stiff!
Rears at 50/50
Raised the front end up by cranking up the torsion bars (because my garage driveway hump keeps hitting my cutouts, and it was (is?) an old-school Mopar trick....
So I definitely have to change the front settings before I drive an hour to the racetrack, then experiment with the front settings there for track conditions, focused on weight transfer and traction without "squirreling out" my steering at 100+mph

 

[biomedtechguy]

Cranked the torsion bars back down yesterday before driving to the track. They messed up my front end geometry too much, and I felt to the point of being unsafe.
Had a bad track day, only 2 runs. On the first run I heard a rubbing sound that seemed driveshaft related because of the frequency. Looked but didn't see anything. Made a 2nd run, hit the gas too hard off the line, blew the tires up in smoke and the noise got really bad...Turns out the pinion snubber bent on the first run, then more on the 2nd. I removed the snubber at the track and that was the source of the noise, it was rubbing on the pinion yoke.
Talked to Mancini and sent pix. I don't understand how this could have happened.

 

[biomedtechguy]

Cranked the torsion bars back down yesterday before driving to the track. They messed up my front end geometry too much, and I felt to the point of being unsafe.
Had a bad track day, only 2 runs. On the first run I heard a rubbing sound that seemed driveshaft related because of the frequency. Looked but didn't see anything. Made a 2nd run, hit the gas too hard off the line, blew the tires up in smoke and the noise got really bad...Turns out the pinion snubber bent on the first run, then more on the 2nd. I removed the snubber at the track and that was the source of the noise, it was rubbing on the pinion yoke.
Talked to Mancini and sent pix. I don't understand how this could have happened.

I picked this issue up in the thread I started about getting and adjusting the pinion snubber.
https://www.forbbodiesonly.com/mopa...t-one-coming-and.152136/page-2#post-910973769

 

[383man]

I know like Doug said most guys I talk to with stick shift cars say they cant hook good on radial tires ? Myself I love the 30 x 9 radial slicks I use and they hook great for me but my car is an auto. I just know all the stick guys I talk with do not run a radial tire as they say they don't work good on the stick cars. I have never tried them on a stick car myself. I would listen to Doug (DVW) as I know him and his son have video'd their cars and done a lot of working on shock settings. I don't even run an adjustable shock in the back of my street car as I just use the SS springs and the longer rear shocks. Its old school but it works ok for my low buck operation on my street car. My best 60 ft is a 1.50 dead hooking on that combo running 10.70's with a 9.5 Dynamic converter. If I ran the mono Cal Trac setup I may get my 60 in the mid 1.40's but the old school SS springs and longer extending rear shocks work ok for my budget. Ask around and see what some others say about the radial tires on the stick cars as I hope you get yours working real good for you. Good luck with it , Ron