Work-in-progress: my 1999 Miata

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slugg

Diamond Member
Feb 17, 2002
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Oh yea, forgot to mention... also added a Wilwood adjustable brake proportioning valve (visible in the picture below). The picture was taken while some friends were walking me through a timing belt and water pump job:
95FFBD80-68A5-487F-942D-B37731362DB5-8827-000007E69B10054B.jpg


I also tried the Flyin Miata swaybar set. It turns out that I actually prefer the upgraded front bar with the stock rear bar, so I sold the rear bar. No pics for that; not much to see anyways.

Edit: oh and the giant dent on the hood was fixed.
 
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phucheneh

Diamond Member
Jun 30, 2012
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I'm not familiar with massive audio, but I'm gonna assume you did some research, since you did it 'right' with components and good amplification.

Even though you've got no sub, you're still going to want to run a high-pass on those door speakers to keep from ripping them apart- remember that half the frequency means (if the power's there, which it should be) twice the excursion. So once you get down into the the 'sub' frequencies, there's opportunity for mechanical damage from over-excursion. I'd try about 50hz maybe, and crank up something with some bass to see how they do. Doing a good job of deadening the doors will help with lower frequencies, too.

Where'd you mount the tweeters? I'd probably go A-pillar, facing in (similar plane to door speakers) on a convertible. They'll get drowned out on the doors unless you aim them right at you.
 

slugg

Diamond Member
Feb 17, 2002
4,723
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I'm not familiar with massive audio, but I'm gonna assume you did some research, since you did it 'right' with components and good amplification.

Even though you've got no sub, you're still going to want to run a high-pass on those door speakers to keep from ripping them apart- remember that half the frequency means (if the power's there, which it should be) twice the excursion. So once you get down into the the 'sub' frequencies, there's opportunity for mechanical damage from over-excursion. I'd try about 50hz maybe, and crank up something with some bass to see how they do. Doing a good job of deadening the doors will help with lower frequencies, too.

Where'd you mount the tweeters? I'd probably go A-pillar, facing in (similar plane to door speakers) on a convertible. They'll get drowned out on the doors unless you aim them right at you.

The CK-6 is a very good bang-for-your-buck component speaker set. It's around the same price as an Alpine Type-R, but gives you a bit more performance in my opinion. The frequency response from 70 hz and up is pretty flat, with 60 hz still being pretty strong. I run an active HPF at the head unit at 50 hz, but the passive crossovers have all that stuff built in. These are truly "plug and play" without much danger of blowing anything up, as long as your amp is decent. I used foam speaker baffles and "ported" them for the wiring and air displacement, but that's pretty much as far as I'm going to go. Insulation is kind of pointless in a Miata (super noisy car = futile), so it adds unnecessary weight. I already have a heavy Miata, considering I have a rollbar, soft top, AND hard top.

The NB Miata with the PEP package (like mine) already comes with components from the factory. I just put the tweeters in the same place where the factory ones were. You're probably right, the a-pillar may be best for the audiophile, but in terms of practicality, nothing beats the completely flush and nice looking factory hole with the grille. I'll post pics later, once I get my replacement amp. Part of it, too, was to deter thieving eyes. My stuff looks stock. The head unit is also very plain, by design. It's just a single din Kenwood Excelon something or another. Good SNR, low distortion, clean signal to the amp. :p
 

phucheneh

Diamond Member
Jun 30, 2012
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Ah, ok, I didn't know the car had comps to begin with. Or 'semi-comps,' maybe. Most are just full range door speakers and then a tweeter with a high pass. Which can still sound damn good, depending on the vehicle.

So much of a stereo is in the setup rather than expensive gear. I'm all for simple headunits (though good EQ'ing options are nice to have), cheap, effective amps, and relatively inexpensive speakers. I've heard some high dollar stuff sound like garbage because of bad installation and poor setup (e.g. EQ and active crossover settings).

Like I said, I think you did good. I was just worried you did like some people I've seen, and bought comps but buried the tweeter down low near the mid. Ruins one of the biggest reasons for comps, which is the so-called 'sound stage.' Although it does usually keep drivers on a similar plane. That's what I would dislike about up-facing dash speakers. You're gonna get the sound bouncing off the windshield and causing some cancellation, plus there might be timing issues.

But like you said, that's kinda 'audiophile' stuff that is hard to really worry about in a 'vert. Lipstick on a pig and whatnot...although with your hard top on, I would think you might still be able to create a half-decent sound environment.

I would still recommend getting a little deadener in the doors. A couple pounds per door isn't exactly going to noticeably hinder performance, and just a light layer of good aluminum/butyl deadening mat, with a little extra concentrated behind the speaker, can do a lot. Ideally, the rear wave from the speaker should be inaudible; you don't want it reverberating around inside the door and make the outer skin vibrate. You can pick up a lot of bass with a little deadening.
 

Imported

Lifer
Sep 2, 2000
14,679
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I'm looking to upgrade to 15x8 wheels (largest that can fit with stock springs) for autocross and daily drive my black Team Dynamics wheels. These 14" ugly stock wheels are really starting to bother me, especially now that the car is coming together nicely.

I think the best you can do with stock springs for a 15x8 is 6ULs. The offsets don't really require anything special from what I've gathered. Most of the other 15x8s run at +20/25 offset which (according to Good-Win) requires -1.5 camber.
 

slugg

Diamond Member
Feb 17, 2002
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I think the best you can do with stock springs for a 15x8 is 6ULs. The offsets don't really require anything special from what I've gathered. Most of the other 15x8s run at +20/25 offset which (according to Good-Win) requires -1.5 camber.

I need a ~+35 offset to run 225/45/15 tires on a 15x8. The 949 6UL is pretty much the best it gets for the money. The annoying thing, though, is that I can't find them anywhere that also sells tires, besides Goodwin. But Goodwin overcharges for tires and doesn't have what I want (Hankook RS3).

That being said, I'm not winning any money autocrossing, so I'm taking my sweet time. As long as my heatcycled StarSpecs have tread, I don't mind sliding my ass around some cones. They're losing their grip, but it's still fun! :)

(I'm cheap)
 

thedarkwolf

Diamond Member
Oct 13, 1999
9,032
125
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You might want to try disconnecting the rear sway bar completely. Seems to rotate better that way and you don't lift one of the rear tires in turns turning your rear diff into an open diff.
 

JCH13

Diamond Member
Sep 14, 2010
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I need a ~+35 offset to run 225/45/15 tires on a 15x8. The 949 6UL is pretty much the best it gets for the money. The annoying thing, though, is that I can't find them anywhere that also sells tires, besides Goodwin. But Goodwin overcharges for tires and doesn't have what I want (Hankook RS3).

That being said, I'm not winning any money autocrossing, so I'm taking my sweet time. As long as my heatcycled StarSpecs have tread, I don't mind sliding my ass around some cones. They're losing their grip, but it's still fun! :)

(I'm cheap)

Heat cycled StarSpecs... lulz... good joke. Seriously though, I've never heard of StarSpecs "heat cycling" out. Street tires don't really do that. A local Miata guy ran ~500 auto-x miles on a set of star specs and said they were doing great.

Interesting thread on it: http://forums.bimmerforums.com/forum/archive/index.php?t-1720264.html

The endurance team JLee and Black2NA and I drive with use StarSpecs and none of us have noticed heat-cycle or other long-term degradation. Scrubbing off some old rubber before an event is a different story.

I've got 15x7.5 C1 from TireRack with RS3s on them. A sacrilegiously narrow wheel according to some, but I really like the forgiving nature of a stuffed tire, and it still grips like nobodies business. Even Miata-driving auto-x instructors were impressed.

You might want to try disconnecting the rear sway bar completely. Seems to rotate better that way and you don't lift one of the rear tires in turns turning your rear diff into an open diff.

This is what I was going to suggest with the sway bars. I've only heard good things about it. I'm going to try it out on my Miata one of these years...
 

slugg

Diamond Member
Feb 17, 2002
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I did try it with the rear bar unlinked. I didn't like it. The car just plows and nothing else. Maybe it would be different if I had more grip, but for now, I like it as it sits.

I definitely don't have as much grip as I should. Maybe it's an alignment issue; I don't know. People have suggested that my star specs are getting old and hard.
 

JCH13

Diamond Member
Sep 14, 2010
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Miatas are super-sensitive to alignment. I got my Miata aligned and it was like driving a whole new car.

How old are your StarSpecs?
 

slugg

Diamond Member
Feb 17, 2002
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My StarSpecs are a little over 1.5 years old. Autocross once or twice a month, one "enduro-cross" where the tires felt greasy after getting really hot, and one gymkhana.

I can get a deal on a top-of-the line alignment. I got a buddy that works at a Mini dealership and they have state of the art everything. $80 bucks for a custom alignment. The problem is that I don't know what specs I should go for...
 

thedarkwolf

Diamond Member
Oct 13, 1999
9,032
125
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Best alignment you can get is the old fashion string and level dohicky kind. One of the guys in our SCCA region has all the tools to do them himself and did my miata for me. He would set the alignment on one wheel and roll the car back a couple feet and then roll it forward to the original spot and recheck the alignment which would change do to the tire flex and by a decent amount. He kept doing that with each wheel till we got the numbers we wanted. Plus he did it with me in the car. I can't remember whose alignment specs I went with this time 949racing or one of the many on miata.net. It has been awhile.
 

JCH13

Diamond Member
Sep 14, 2010
4,981
66
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My StarSpecs are a little over 1.5 years old. Autocross once or twice a month, one "enduro-cross" where the tires felt greasy after getting really hot, and one gymkhana.

I can get a deal on a top-of-the line alignment. I got a buddy that works at a Mini dealership and they have state of the art everything. $80 bucks for a custom alignment. The problem is that I don't know what specs I should go for...

I would suggest:
Front:
-1.75 to -2.0 deg camber
0-1/8in total toe out
all of the caster you can stand, I'm at 4.75

Rear:
-1.5 to -1.75deg camber
0-1/8in total toe in

The toe really helps initiate turns and keeps the rear end from walking out too much, but will wear tires a little more quickly. I really liked having 1/8 toe out in front and 1/8in toe in on the rear, my Miata felt like it had telepathic steering with very controllable over-steer.

Best alignment you can get is the old fashion string and level dohicky kind. One of the guys in our SCCA region has all the tools to do them himself and did my miata for me. He would set the alignment on one wheel and roll the car back a couple feet and then roll it forward to the original spot and recheck the alignment which would change do to the tire flex and by a decent amount. He kept doing that with each wheel till we got the numbers we wanted. Plus he did it with me in the car. I can't remember whose alignment specs I went with this time 949racing or one of the many on miata.net. It has been awhile.

When I got mine done at a shop they did the same thing: rolled forward and back to settle everything, and did it with me in the car.
 

slugg

Diamond Member
Feb 17, 2002
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NB's can't get the same camber in the front as NA's. I can only get about -1.1, maybe -1.2 degrees... Unless I lower the car (not gonna happen).
 

JCH13

Diamond Member
Sep 14, 2010
4,981
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NB's can't get the same camber in the front as NA's. I can only get about -1.1, maybe -1.2 degrees... Unless I lower the car (not gonna happen).

Well that's unfortunate. Dial in as much as you can in front then and run the rear around 0.2deg more positive than the front. The toe is the more important aspect to making it respond quickly and feel good I think, camber will just limit your ultimate cornering grip a little. Less camber will improve braking/drive traction a little, so it's not all bad.
 

slugg

Diamond Member
Feb 17, 2002
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Well, I co-drove someone else's Miata last weekend. Another 1999 almost identical to mine with these differences:

1. Rear sway bar was 12 mm (mine is 11 mm)
2. Shocks are Tokico Illumina (mine are cheapo KYB AGX)
3. Wheels were 15x8 with Hankook RS-3 (unbelievable)

I purchased some new 15x8 949 Racing 6UL wheels and half-worn Hankook RS-3's and they're getting mounted/balance as I type this. Pics in a couple days. I also have a 12 mm rear sway bar coming tomorrow for free (traded a computer favor for it, lol). I plan on a new alignment soon. I'm low on moneys from buying the wheels.

The car is on jack stands at the moment... Cooked my brakes at Sebring. Still not done with the R&R (been taking my sweet time). :p
 

JCH13

Diamond Member
Sep 14, 2010
4,981
66
91
Well, I co-drove someone else's Miata last weekend. Another 1999 almost identical to mine with these differences:

1. Rear sway bar was 12 mm (mine is 11 mm)
2. Shocks are Tokico Illumina (mine are cheapo KYB AGX)
3. Wheels were 15x8 with Hankook RS-3 (unbelievable)

I purchased some new 15x8 949 Racing 6UL wheels and half-worn Hankook RS-3's and they're getting mounted/balance as I type this. Pics in a couple days. I also have a 12 mm rear sway bar coming tomorrow for free (traded a computer favor for it, lol). I plan on a new alignment soon. I'm low on moneys from buying the wheels.

The car is on jack stands at the moment... Cooked my brakes at Sebring. Still not done with the R&R (been taking my sweet time). :p

All of this post is massive winning! :awe: :thumbsup:
 

slugg

Diamond Member
Feb 17, 2002
4,723
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Stack of 205/50/15 Dunlop StarSpecs on Team Dynamics Pro-Race 2 wheels versus a stack of 225/45/15 Hankook RS-3s on 949 Racing 6UL wheels:
657864B5-DA4B-4399-8E0C-043DEEA6BE4F-41120-00001E8A455E4890.jpg

^^ That's some serious rubber for a Miata!

Looks like the 949 center caps fit my TD wheels. Good, because I never had center caps for these wheels and now I plan on daily driving them:
EFEA1812-283B-487B-BDB3-C0DD87BD6FD1-41120-00001E8A4F343DAD.jpg



And here's how the car looks with the new wheels. Please note: the car has been sitting on jack stands for over a week and I still haven't driven it, so the suspension has not settled in this pic. Looks like an off-road roadster! LOL
639C067C-BDCE-47B9-825D-52B5857800D6-41120-00001E8A60760985.jpg