Whether 'tis nobler in the mind to suffer body roll yet retain the wonderful balance of the car, or to take up a big front bar and gain...what? Faster transitions?


I'm debating whether or not to go to a bigger front bar (probably the RB 15/16" solid bar... It's cheap!). I really love the balance of the car as it is, but I recognize that there's a lot of body roll going on. But I have to think that by adding the front bar I'll be introducing understeer...

There's also the question of fuel starvation... In flat out semi-tight left handers, the car fuel starves with less than half a tank. I don't know if body roll could contribute to that. We replaced both the fuel filter and the pump sock, so maybe that will solve that problem. Who knows, heh.

 

You will introduce some understeer, mostly in low speed stuff. But the benefit is in being able to get on the power a lot earlier when exiting a turn.

If the understeer is excessive, you can tune it out with alignment. (more front camber if you can get it)

For strictly autocross purposes, I believe the philosophy is to put on the stiffest front bar you can get. The Miata doesn't have a lot of power, so you want to be able to make the most of what it has.

Best of all... a swaybar is easy to change and if you don't like it, you can get most of your money back by selling it.

 

still have the stock suspension or do you have koni's or something?

& if the front bar gives you too much understeer you should be able to add some toe out to the rear to compensate some, ask tony about rear toe out

 

Oh, I know first hand about toe out in the rear, haha. I was the first one to put Tony's car in the dirt at Brooksville. Rear toe out sucks when you run out of talent.


It's got Konis on it right now. I've been running them 1 full turn from soft front and rear. I'm going to try turning up the fronts at Brooksville and see how that feels.

I guess there's no harm in trying a bar... I think the RB bar plus the reinforcement blocks is only like $140...

 

Well, there's another problem. I had Tire Kingdom do the alignment, and one of the front wheels (I don't remember which side) maxed out at 0.95 deg. The other side went to like 1.75 or something. So it's at -0.95 on both sides at the moment....

 

Big front bars are good. Very good. I started with the Addco front swaybar, and have since put 2 more holes in it to make it even stiffer, and Jim and I are contemplating an even BIGGER front bar.

Front bar is good. Tune and drive around any push it creates.

 

I'd wager that part of your camber issue is the off-road ride height. It's also possible that one or more of the cam bolts are badly worn, I replaced all of mine when I went to urethane bushings. It's something to check anyway if nothing seems bent.

 

Tell me about it... But what can you do? You have to use the top perches to be legal for stock class... The ride height went UP an inch in the front and a half-inch in the back after putting the Konis on!


I ordered an RB 15/16" solid bar from GoodWin yesterday, but they're on backorder. He said they have plenty of the HUGE hollow bar, but I think that would be overkill, and it's like $50 more... So I probably won't see a front bar until after Brooksville.

 

I still don't understand how using a stock perch height yields a higher than stock ride height by 1 inch. Doesn't that mean that the perch is 1 inch too high?

 

I think it has something to do with gas pressure in the shocks. I've seen Miatas with completely worn out stock shocks that I'd have sworn had aftermarket lowering springs on them they were so low. A new set of shocks jacked the car up at least an inch. The new shocks do settle 1/4-1/2 inch after a few weeks or so.

In answer to your question, a set of Konis on the upper perch doesn't raise the car an inch higher than stock ride height... the car was an inch LOWER than it should have been before the shocks were installed. The new shocks restored the proper ride height.