Let's talk front sway bars, shall we? Options

[Tdskip]

My '74 914/6 build does not have one. The fuel tank is currently out. Now would be the time to do this, right?

Any tips on diameter for a fast road street car?

[PlaysWithCars]

just my opinion:

but anti-sway bars do not effect ride as everyone keeps saying
think about it... when you are going straight down the road, the bar is free and has no tension.

when you hit a pot hole you feel it as you would anyways... but the sway bar is still under very little pressure

springs/torsion bars effect ride quality
but sway bars do not

they only come into play when the car is loaded into a corner.

I'm running a 27mm front smart anti-sway bar currently

I have to disagree. I've found that big sway bars make the car ride harsher than bigger springs. Your theory is right in that if you are going down a road and both wheels hit the same road irregularity, and move together, then the sway bar is irrelevant. But, in reality it is nearly impossible that both wheels will hit the same irregularity and move together. Usually there is a difference so the sway bars come into play and create a harsh ride. I've found that spring changes can control body roll as well without the harsh ride.

Now, that said, when you add stiffer springs you can use a bigger sway bar and not experience the harsh ride because the stiff springs reduce wheel end movement and hence won't generate as much force from the sway bar. In fact, I've found that larger bars are needed to get much benefit from them when you have stiff springs.

For reference, my current set up: 23mm hollow front torsions, 22mm sway, 225# rear springs, currently disconnected rear sway bar. Its well balanced for autocross, but I'm looking to go a little stiffer in the rear.