Posted By: AndyF
Winston Cup (or GN) rear suspension question - 07/29/10 11:18 PM
Anyone know when the Mopar cars switched from leaf springs to trailing arm rear suspension? I took some pictures of an older Grand National (maybe a Winston Cup) car this week and it still had leaf springs in it. The car is probably from the late 60's or early 70's.
K frame car with torsion bars, Mopar power steering, etc. Obviously a factory frame car but heavily modified. The drive side torsion bar had a jack on it that could be adjusted by the driver to change the preload. Production lower control arms, drum brakes, tubular upper control arms, spline type anti-sway bar, etc. Pretty cool stuff to look at but the rear leaf springs surprised me. I just thought everyone had gone with the pickup truck type suspension back in the 60's.
Posted By: Anonymous
Re: Winston Cup (or GN) rear suspension question - 07/29/10 11:53 PM
Late '60's is when Junior Johnson started using the truck arms on Ford applications and they were mandated across the board shortly thereafter. Not sure of the exact year.
Posted By: AndyF
Re: Winston Cup (or GN) rear suspension question - 07/30/10 12:13 AM
Here is a shot of the cage structure. The leaf spring hanger is just barely in the shot over to the bottom left corner. Not sure what year this car was built but it appeared to be a late 60's B body from what I could see. K frame is still there as is most of the front suspension, steering box, etc. Battery is behind the passenger front tire rather than in the back wheel well.
Posted By: fourgearsavoy
Re: Winston Cup (or GN) rear suspension question - 07/30/10 01:33 AM
I believe Banjo Mathews started putting truck arms on B-bodies in late '67
Gus
Posted By: '72CudaRacer
Re: Winston Cup (or GN) rear suspension question - 07/30/10 03:29 AM
One of the funniest comments about those cars came from Buddy Baker a while back. He was ask how did he think the car that he set the closed course speed record with (now in the museum at Talladega) would do with todays knowledge, tires ect. His remark- "back then (1970) those cars were top shelf equipment. I look at that car in the museum now, and I wouldn't climb out of the electric chair to drive it today". My, how far they've come in 40 years
Posted By: AndyF
Re: Winston Cup (or GN) rear suspension question - 07/30/10 04:33 AM
Here is the torsion adjuster in front of the driver's seat. Guess the driver just carried a wrench with him and cranked the left side up or down as needed.
Posted By: AndyF
Re: Winston Cup (or GN) rear suspension question - 07/30/10 04:37 AM
Here is another GN era car. This one is a little different but roughly the same era. This car has the K frame moved up into the frame and welded in place.
Posted By: A70Runner
Re: Winston Cup (or GN) rear suspension question - 07/31/10 03:23 AM
I am restoring a Jimmy Means 1976 Laguna stock car (Started as a older 73-74 Monte Carlo/Chevelle Old #12 car which is pretty Ironic considering I work on the 12 car now) Anyway...It has a truck arm susspention. I think back then it was all by who built the chassis. Who's car was it? Looks petty blue or Marcis blue hard to tell in the pictures.
Posted By: TrWaters
Re: Winston Cup (or GN) rear suspension question - 07/31/10 05:01 PM
The Chrysler kit cars of the late 70's all used torsion bars and leafs.
Nothing like picking up a possible wing car for under $3K. 
Later I heard he bought it and drug it home. 
