I have a '65 Dart 273/4,4.10 and 9.5 conerter. I was/am building this combo as a IHRA Pure Stock. Cam is factory spec with the AFB carb and Eddy/Chrysler aluminum intake. All I need now is the rear suspension to be updated since this was originally a /6. 2 002 SS springs or 002-003?

9.80's many many years ago on 002-003 super stock springs and track prep today is WAY BETTER.



16105924_1102724759836901_8490742865654210794_n by John Cadamore, on Flickr


74 Duster at Halloween classic 001 by John Cadamore, on Flickr

Are Caltraks legal in your class?

If they are I sure as heck would buy them over super stock springs. They flat-out work.

Just asking, but didn't IHRA pull the plug on class racing?

No Cal Tracs. Must be leaf springs. Yes IHRA pulled the plug on sportsman racing but I can run the car at my local S/SS association events. The factory 273's never made 235 HP in the real world. They averaged about 220 when the motors were run on dyno back in the early 80"s. Since they didn't make a lot of torque I thought that the SS spring would be overkill and somewhat heavier than a stock spring. Didn't know if a street style 340, A body leaf spring would work better. If I needed to tune it, a short spring up front clamped might do the trick. That's why I asked if two 002 springs would be better than the heavily biased 003.

No expert but have 6 yrs racing experience with my stock s/strip 340 Cuda, my springs were clamped up front and I ran a snubber, thats all, worked great at stock 300hp level all the way up to 533hp and we only ran standard long shocks, nothing fancy back then.

I think the 340 spring idea would be a better choice than SS springs in that combo.

What's the source for good quality 340 springs? Did Chrysler make a distinction between auto and stick leaf springs? Mopar's XHD leaf springs that Mancini sells any good?

If your local track is following the old IHRA Pure Stock rules you can use Slide-A-Links which the Calverts closely resemble. A bo,t on suspension aid was legal in IHRA as long as you used the standard front and rear eye locations. I ran the Slide-A-Links back in 2003/2004 in B/PS.

Keep it simple, use the 002-003 springs and a good shock. Try to buy a used set that's starting to sag (they're broke in for that little motor). My opinion, with that gear and converter you're leaving a lot on the table that won't work those springs.

I would use the 340 springs. Look at the thread member Pro Sport has on his new Duster. He added a leaf to the stock springs and his 60ft is 1.50.

My mid 10 sec duster has stock leaf springs, I had a local spring company called Stuver Spring add one new leaf per side, leaf is slightly thicker. This stiffens the front segment, no snubber.
Cost was $50 per side.

I have the MP 3400 lbs springs I bought from Mancini. They are still holding up fine and work good on my 3725 lb 63. Ron