Miata Question

[Dtangard]

Thanks Will for the info. I never even considered slop in the rack from removing the power assist. I think since the car will probably see some autocross days I'll keep the power steering for now but if I come across a cheap power steering rack I'll try the miatabusa depowering method.

[TroyV]

I broke a PS line at NJMP and had to run a practice session, the TT, and the open session without PS. ...my arms were like jello after the open session....but I'm sort of a pussay anyway...

I have to say I agree with Will. I can feel what the car is doing just fine with the PS active.

[6PAK72]

And SOME people who might consider themselves a pussay laugh at it (Troy), but I had to put a smaller steering wheel into our Miata so that Liz and I could share the car. It's a 300mm Moma (OEM is 350mm). The smaller steering wheel combined with the power steering rack feels really great - inputs on the wheel now are linear to what is happening with the steering outcome.

You're welcome to try ours at some point, if you wish.

[CP]

I too bought my first donor car from Leos at Expoline and turned it into a racecar a few years ago. He's also good for last minute parts needed after a tangle with competitors or the wall but be prepared to pay. I now carry a spare set of taillights with me to races.

On the PS issue: If you push most of the fluid out of it before sealing it up, steering effort isn't too bad. I've found that my frail girly arms begin to get tired near the end of a 25 minute race at NHMS...not so much at WG or LRP. Another key to keeping your arms fresh is how close the steering wheel is located in relation to your body. Ever notice that NASCAR drivers' steering wheels are almost touching their chests? They're wheeling for 3-4 hours at a time. I added 3-4" of extensions between the wheel and quick disconnect hub which keeps the wheel close to my body while allowing my long legs room beneath. When I'm strapped into my seat I can barely touch the buttons on my lap timer that's mounted to the instrument cluster 6-8" behind the wheel. I also shimmed the column down a small amount with some washers and longer bolts (two of them under the cluster). The result was wheel placement exactly where I wanted it. If you don't shim the column after adding some length it places the steering wheel too high. www.boltdepot.com is a good place for longer bolts for the QD hub and they're close in Weymouth, MA with quick shipping.

[Dtangard]

After some thought, I think what my car really needs is a new steering wheel and some new front bushings to get the steering feel where I want it. Thanks for all the info guys.

Next question:
Has anyone ordered a new clutch kit for a miata in ST4? The stock clutch in my car starts to slip after 2 laps at NHMS so it's definitely time for a replacement. Do you guys think its worth buying an aftermarket clutch legal for the class or sticking with the OEM? I'd like to think a newer OEM clutch could hold up to 25 minute lapping sessions.

[paultg]

Derek, others with more seat time are probably better to listen too, but I've driven a 92 Miata at NHMS with 130k +\- and it had no clutch issues, even when my instructor drove it for a session. This car had an original clutch.

My current 91 has a oem replacement clutch with about 70k miles on it. It handled Calabogie just fine.

I'll probably go with this when I get around to replacing it ($109):
http://finishlineperformance.com/store/ ... t=0&page=1

[Grippy]

Mazda Motorsports offers a stock pressure plate that has reworked springs that have +30% more clamping force than stock. That used with a stock clutch disk is a very good combination that has stock feel and is much cheaper than aftermarket choices. I had that combo in my old (Jeff W's current) class winning car, it held up to years of track use without issue.

[nateh]

We've got 20K track miles on our old puppy. No clutch problems yet.

[WillM]

Mazda Motorsports offers a stock pressure plate that has reworked springs that have +30% more clamping force than stock. That used with a stock clutch disk is a very good combination that has stock feel and is much cheaper than aftermarket choices. I had that combo in my old (Jeff W's current) class winning car, it held up to years of track use without issue.

+1. Great advise. I've had the same on a few cars.

[Dtangard]

I ended up buying the mazda motorsports +30% clamping force pressure plate and the stock disk. I can't wait to install it and since I've never replaced a clutch before this should be fun.

[CP]

Be glad that these cars have transmissions that you can lay on your chest without having a coronary. Find a good how-to and follow it. Be sure to get the car up good and high on the jackstands or you won't be able to rotate the engine enough to get the trans off of it. Replace the throwout and pilot bearings and the flywheel while you're in there. It's easier than having a machine shop mess with it to resurface and costs about $100. Torque the pressure plate bolts a little at a time and alternate with bolts across the flywheel from each other. There are lots of good tips on specmiata.com or miata.net if you search.

[chaos4NH]

Slightly off topic, but couldn't resist posting when I read of the complaints of high steering effort on non-PS Miatas. During the early January blizzard, my Dodge 2500 plow truck destroyed its power steering pump on the first day of the storm. I plowed my roughly 2 acres of of farm roads and pathways, for 2 days without the PS, with 1,400 lb plow dangling off the front. I now have 20" biceps.

[CP]

It may be worth looking into a more performance oriented clutch disc than the stock unit. I personally run a 4-puck unsprung ACT disc in my SM, but I think a sprung 4-puck would be perfectly streetable.

[Dtangard]

Hey CP,

What's the advantage of an unsprung disk? Do you think the stock disk will overheat? For what its worth I'm not too concerned with streetability. My aluminum seats killed the streetability of the car anyways. After a track day at NHMS and driving back and forth I'm stuck in the seated position for the rest of the night and I'm only 21...

[breakaway500]

"What's the advantage of an unsprung disk?" No springs to break with repeated abuse.
I run an ACT 4 puck unsprung hub disc in my Miata as well.(handling about 220whp)Other than being a bit grabby when cold,it's fine,even for street use.. Last time I removed it for inspection, the friction pads had zero wear over a new one,and I ran it a lot the last two years. I like the setup enough to install one in my Focus as well.