What have you done to your Miata today?

[aMaff]

It just seems a little unholy to not have a rear sway bar at all, and a number of experts (including FM) suggest having a rear sway if at all possible. Eventually I'd like to do the tried-and-true RB tubular front sway and stock rear sway.

The rear sway can almost certainly be made to work on tracks where, at speed, it's harder to get the rear to rotate. FM doesn't really have much focus on autox. What front do you have? I'm running no rear + the RB big f**k off "race" front sway. Tune the rear with springs if it needs to be stiffer, because keeping the drive wheels independent is good for going fast at an autox.

I'm planning on leaving mine disconnected all the time. Not over-steering on the street is probably more important than during autox. From a 'keeping the car not crashed' perspective anyway (I don't mean that as a dig at you, I mean that in a 'I saw my fiance get sideways on an entrance ramp when the turbo spooled up and I didn't really like it' sort of way).

Agree with all of that.

 

[princess peach]

I'm planning on leaving mine disconnected all the time. Not over-steering on the street is probably more important than during autox. From a 'keeping the car not crashed' perspective anyway (I don't mean that as a dig at you, I mean that in a 'I saw my fiance get sideways on an entrance ramp when the turbo spooled up and I didn't really like it' sort of way).

haha you're fine. I never had issues on the street except when I first got it and it had bad tires so driving in the rain was interesting. The NA I'm getting has frog arms, butterfly brace, ST coilovers (will most likely put my suspension on), FM sways and 949 end links. I drove Will's on Sunday and loved it, a bit loose but might have been the brand new tires that needed to be scrubbed. He's borrowing my suspension and I believe has BR front and stock rear, he bought my rear MSM bar but I believe he hasn't put it on yet.

I'll have to try both ways, but besides FM 949 also claims that having a rear bar is a must for track days. Hard to say who has the absolute truth, guess it's down to personal preference

 

[JamesCH]

I have both FM bars, 7/8in solid front and 5/8in solid rear.

Having thought about it for a few minutes it makes sense that track cars would want a rear sway: they're in a higher gear and thus have less torque applied to the rear wheels (and thus need more help getting the car to oversteer), and having better steady-state balance through long sweeping turns would be more beneficial than at autox.

 

[THE Phen]

I ran without the bar most of last summer (after Andrew said "Hey dummy, disconnect it"). Bar is still off the car after selling it. It felt soooo much more stable all the time. Had I kept the car, I wasn't going to put it back on unless I had a really big front one and needed rotation. Of course, rotation on that car was giving it a little more right foot.

 

[aMaff]

I have both FM bars, 7/8in solid front and 5/8in solid rear.

Guh, stick with the stock rear at most lol. I've got it in the shop to have "just in case" I need it. I wouldn't put a *bigger* rear bar on (obviously). But yeah, on track with much less torque to the wheels, I can see it. Even though, honestly, I think that can be better tuned with springs than sways. It's a more difficult change to make, but I'm not a huge fan of lifting the inside rear off if you don't have to.


But for autox? Nope. Nope nope nope.

 

[WillD]

I think "generally", it is easy to say disconnect the rear bar. But it is wrong to just make that statement without taking into account spring rates and front bar at the very least. Alignment plays a big factor on rotation as well.

I have a the Racing Beat .188 wall "race" bar set to full stiff with the blocks and bolts. I have the 12mm stock bar. I wanted a MSM bar (14mm) just as a different option down the road once I get the Xidas which are 700/400 spring rates.

 

[aMaff]

You're right, it's not universal, but I've never been in a non-stock Miata that disconnecting the rear bar didn't make immediately better. Yes you can probably find some weird, off the wall suspension set up that works better with it connected, but I haven't come across it yet.

 

[JamesCH]

Heh, I might have a prayer at my next autox meet now!

 

[JamesCH]

Tightening up a hose clamp fixed a leak in the coolant re-route. *phew*

 

[JamesCH]

I had argued against painting ICs black at one point. Here is an interesting (but possibly flawed) test suggesting that it might not be bad, and in fact might help in certain circumstances:

https://www.youtube.com/watch?v=f1QL9veQaNg&feature=youtu.be

I'm left wondering what the ambient temperatures were (crucial to this sort of test) and what the difference between gloss black and matte black would be, and if a serious chemical etch on the IC (to get the matte texture) would have been better.

 

[Reitrof]

Finally got around to installing my seat lowering brackets.

 

[JamesCH]

I must have been drunk when I did the last alignment on my car or I must have slipped every camber bolt, because it was terrible. I re-did the entire alignment on my car on Sunday and found a lot of issues. Toe and camber in the rear was just awful, and caster in the front was all out of sorts, but it's better now.

F:
-2.6deg camber
1/16in toe out each side
maxed out even caster on both sides, wound up with 4.6deg or so.

R:
-2.9deg camber (I know this is a lot of a street car, but its where everything seemed happiest)
1/16in toe in each side

With FM Stage 2 suspension, sans rear bar, this alignment is very responsive on turn-in with great steer wheel feedback without feeling 'darty' on rutted roads and feels very stable in sweeping turns, especially on-throttle. It doesn't turn-in as eagerly as 1/8in toe out per side on the front axle, but I think I was roasting tires quickly with that much toe.

 

[aMaff]

It doesn't turn-in as eagerly as 1/8in toe out per side on the front axle, but I think I was roasting tires quickly with that much toe.

1) Figure out how many turns of the outer tie-rod it takes to give you that full 1/4" toe out

2) Take 3 minutes before events to make that change. It's an autocrosser, your steering wheel not being straight will not affect you, because when is your steering wheel ever straight during an autocross run?

3) Take 3 minutes after the event to change it back.

 

[JamesCH]

1) Figure out how many turns of the outer tie-rod it takes to give you that full 1/4" toe out

2) Take 3 minutes before events to make that change. It's an autocrosser, your steering wheel not being straight will not affect you, because when is your steering wheel ever straight during an autocross run?

3) Take 3 minutes after the event to change it back.

That's not a bad idea at all. I could probably even figure out a marking system to re-align almost perfectly.

I think I figured out what things were so messed up: the last time I did an alignment I didn't have a handy laser level and the car probably slid sideways a little when I was reffing on a cam bolt. This caused all of my toe adjustments to point right!

 

[WillD]

James you have those FM alignment stands right?

 

[aMaff]

the last time I did an alignment I didn't have a handy laser level and the car probably slid sideways a little when I was reffing on a cam bolt.

*cough*
http://www.saferacer.com/iron-canyon-spec-miata-alignment-system

Worth every penny when you're not having to worry about how the car itself is positioned.

 

[JamesCH]

Yes I do. Their guide to finding a vehicle center-line with string and using their silly indicator tool leaves much to be desired.

 

[JamesCH]

*cough*
http://www.saferacer.com/iron-canyon-spec-miata-alignment-system

Worth every penny when you're not having to worry about how the car itself is positioned.

Yup! That is likely next on my list of alignment stuff to get.

Though the laser-level took care of most of that concern (I can quickly and easily tell if it moved, and quickly re-align the laser), now I just need to find a way to attach the laser to the car and it'll be almost fool-proof.

 

[WillD]

Having never aligned the car myself, I have no idea what that is... or how it would be used.

 

[aMaff]

Having never aligned the car myself, I have no idea what that is... or how it would be used.

Decent image. Basically, it allows you to set your toe and thrust angles, without any regard to where the car is positioned on the ground, as the strings stay on the car. It takes exactly the same setup as using fishing line on jackstands, except if you wiggle the car a fraction of an inch, you don't have to re-set everything.