Quote:

I'm trying to decide what suspension to complete out the rear of my car with.

I've currently got a set of really worn out HD springs on the back of my car that have settled to a near zero arch. I've also picked up a new set of XHD springs to replace them.

At the track I'll be running an ET Street DR or Conventional ET Street. At least a 10.5" tire.

The rest of the driveline will be a centerforce DF, 1350 DS and a 3.54 Powrlok Dana 60.

Will XHD leafs with the threaded style pinion snubber work for a 600rwhp car? Or are Cal-tracs needed? I've got Koni's and 1.24" torsion bars up front, so I really need to get to about 150/lb springs to get what I know is "matched".

I would like to imagine that well below a 2.0 60' could be done easily....



Not sure how your planning on driving the car off the line, but my first year with a 5 speed and slow mid 13 second car I had a pinion snubber (adjusted properly) and leaf springs with an extra leaf added to stiffen them up (very arched) and adjustable shocks and the car hopped like a lowrider on the launch dumping the clutch at around 3500-4000rpms...I can't imagine things getting any better with added power, and to be honest if super stock springs don't work (and im kinda thinking they won't) caltracs really are your best option. I'd get rid of those XHD's for a set of the calvert mono's and either look into caltrac bars or the smith racecraft assassin bars and good rear shocks. You will need good shocks and a good traction system to control the hit with the stick if you plan on leaving with any kind of power or aggressiveness (i.e. not riding out the clutch)

As for tires, you won't hook worth a damn with drag radials and a stick...I know from experience with this, even on slower cars, radials just don't like the dump of the clutch and tend to be very inconsistent. Use the conventional ET streets. Also, you don't seem to be short for power, but that is not enough gear to maximize the potential of the car (atleast in my opinion). I know you are building a hemi, but the powerband of the motor will dictate the gearing. Sticks like a higher numerical ratio, but you might be ok with what you have. Best is to try it and see- 60's might suck and it may not trap where you want, so a ratio change may be in order.

I have had good luck leaving at 5000rpms off a two step with a CF DF clutch, and I know of a couple of mustangs here running high tens with the same clutch at 3100-3200lbs race weight. They are a good clutch for what they are. I would try it and see how it works, although you may need an adjustable clutch.

I would take it out and see what it does. Make a pass, if things get out of line, stop before you break anything and then address the problems. Im no expert, but I ran the stick for the past three years at varying power levels (never at yours though) so I have learned a few things about what works and what doesn't.

Good luck man!