Talking to one of my more 'dirt track' car buddies, he mentioned that blocking the rear of a live axle car so it had zero suspension travel was a cheap and effective solution for drag suspension when running drag slicks.
Seems to me like you WANT the weight to shift back in a rwd car, am I wrong? Discuss.
Also, what about FWD? It does seem like for FWD you want as little weight shift as possible, so maybe blocking the rear suspension would be a benefit?
Suspension movement is a result of weight transfer, not a cause. Blocking the rear suspension will change the rate at which the weight moves, but it won't change the amount.
FWD drag racing is simply banging your head against the laws of phyisics 
In reply to Robbie:
If you're asking for Challenge purposes I already got denied when I asked about running live axle with no suspension.
My impression is that the main reason for running zero rear suspension is for wheelies?
Stiff as possible in the rear and loose up front. Pretty common with drag racing in general. Unhooking the front sway bar and stiffer rear springs picked up 2/10ths in the 60 foot for my capri.
Interesting. So no suspension means the weight shift happens instantly (or almost)?
Stiffer suspension means faster weight shift right?
How would you negate wheel hop?
In reply to 914Driver:
Varying tire pressure? Launch style? You'd remove a bunch of the variables involved in setting up an oscillation by removing springs, bushings, linkages, so I'd think that you'd only have wheel hop when you had a system that interacted badly with the frequency of the tires.
Very tall drag slicks deform a lot during the launch, watch some slow mo videos. A lot of launch tuning is done with tire pressures. Most funny cars, dragsters, and roadsters run no suspension and tune with tire pressure.
Welllll, for what it's worth, the fastest car in my Challenge experience runs some pretty soft rear suspension. I'll wait and see what Wheels777 has to say.
Shocks play a lot into this too, but weight transfer is also controlled by the location of the instant center.
Most Wheel hop is due to springs or bushings wrapping up and unloading. For Leaf springs add a traction link or slapper bars. Solid joints replace compliant bushings.
Again calculate the instant center to see how that is affecting performance.
I say weight transfer but that is not the right term, it's more about leverage.
Without forward thrust there is little weight transfer and the leverage controls how that is applied to the ground.
Depends on drive. FW or RW.
For FWD a much stiffer rear suspension may help, on RWD it is just the opposite.
Type of tires have an effect on wheel hop as well as suspension bushings and use of the clutch.
My Hoosiers would spin with no hop while the stock tires would. The Hoosiers being cold might be some of the reason.
On my FWD Buick I ran "Helper" air shocks in the rear. When I raced I put about 80lbs in each one. It raised the rear about 6 inches and made them virtually solid.
It didn't make my car faster, but it did make it run more consistent. When you're bracket racing, that's the name of the game.
What works best will depend on the tires. A drag slick will handle a much bigger shock load (due to squishy sidewalls) than a street tire, so it'll take a different setup to put down max power as quickly as possible without wheelspin.
I know many people who picked up tons of ET by adding a four link instead of a solid rear on mid powered drag cars, mostly because you run more than 100% antisquat.
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