[Tim]

What's the difference between the way a torsion bar and a sway bar works? Which would give the best results in decreasing 60ft times, and which would most improve handling on the street?

Would a front sway bar give any benefit on the strip?

Any advice/ clarification would be greatly appreciated.

[dave-r]

The lighter the spring rates at the front the better the weight transfer. Most drag cars use no front sway bar at all and slant six torsion bars.

[dave-r]

Let me expand on what I said above.

For Drag racing you want as little spring rate at the front as possible but stiffer rates at the rear. The light springs at the front will cause the front to lift faster. The stiffer rear springs will help plant the rear tyres. A front sway bar will increase the front spring rate so you don't want that. A rear sway bar will help launch the car straight and control axle movement.

On a street/strip car you might want to run a front sway bar for normal driving and just disconnect it or remove it at the strip.

For handling you want very high spring rates all round and they need to be balanced front/back so that you get no oversteer or understeer or maybe just a bit of one or the other depending how you like the car to handle.

For comfort you need soft (not too soft!) spring rates but you can use sway bars with a high rating to control body roll.

In all cases I would use a rear sway bar.

[dave-r]

And one more point. My car is set up for handling not drag. It still runs high 11s. I don't see the point of having a fast car if I have to slow right down to go around corners? I don't want to give up that performance and safety advantage just to loose a couple of hundreths on the quarter mile.

[72 Challenger (Hans)]

I had a loose swaybar and slant six torsion bars for the better weight transfer...oh and 90/10 shocks in front. Weight transfer was great, always had traction on the strip. Just don't go cornering like a mad man...

[Tim]

Thank you for the feedback guys, all good food for thought.

I've mentioned elsewhere that I'm planning to replace some of my body panels with fibreglass items over the next couple of years. I worked out that if I was able to lose 300kg in body weight (estimated 3900 lbs down to around 3200 lbs) my ET's would drop from the current 12.99 to 12.10 seconds, without any other changes.

However, I think the reduction in weight would mean I have to work harder at getting traction off the line (less bodyweight means less weight transfer?), so I need to think about optimising traction, but not at the cost of reducing everyday handling.

A good rear sway bar seems to be a good start, giving me a clean straight launch, but also aiding cornering on the road. I don't want to get into using drag shocks (tempting though it is) as the valving is all wrong for road use. Maybe adjustable shocks on the front are an upgrade for the future, as they can be set nice and firm for the road, but adjusted for quick extension at the track.

My only other thought is to swap the leaf springs out for a set of coil- over shocks, but I don't know if I want to alter the car to that degree. I presume there would be a further reduction in weight, and an improvement in on- road handling? Would I see much improvement on the strip?

One of the benefits of trading up to a coil/ shock rear suspension seems to be that you can easily tailor the shock rates, spring rates and ride height to your own requirements. Is there a formula for calculating the correct spring type/ rate for individual applications?

This is all stuff I'm just toying around with at the moment, but I'd be interested to hear some more feedback.