STS2 Miata Build Part Deux - 2008

[dmitrik4]

i don't think "useful" and "autoX nerdery" are necessarily mutually exclusive. to 99.5% of all autoXers, those small details are insignificant, but when you're at Andy's level, all that little stuff matters. when championships are won and lost by thousandths of a second over the course of two days, it matters. it's why guys spend hours tracking down the parts to lose 5-10 pounds from their cars. it's why they spend years tuning their car.

i'm disappointed that emelio is only making 20 sets of wheels; i have other things to take care of (like replacing my blown stock suspension), and i'm sure he'll be sold out by the time i would get around to buying. oh well...i'll stick w/ my K1-TSs. they look better on the car anyway, and from what i've read, the extra width isn't as big a deal on the Bridgestones i'm planning on running as it is on the Falkens.

 

[aMaff]

Ok, long due update time:
Progress!!!

Got all but 2 bolts on the transmission off (just to hold it in), the drive shaft and broke all the bolts for the power plant frame loose. Next step is to get some taller jack stands (so I can actually get the thing out from under the car. Did a test fit w/ the spare, totally won't get under there

Organization ftw!

That's basically it through yesterday. I won't get to really work on it in earnest again until Sunday or Monday night.

I've got a couple hours tonight to play with the suspension. I'm going to take the springs off of a front and rear shock and see how I'm looking wheel-travel wise. In the front I've been hitting the top of the tire on the inner fender bodywork before I hit the bumpstops, so I want to see how much spacer I need to make the bump-stop functional again. This should be fairly easy since the car's already up in the air. Only hard part is getting to the upper rear shock mount bolts. And that's not really hard, it's just a bit of a pain. There's this AWESOME perfectly sized crevice around the shock tops so that when you remove the nut, if you're not really carefully, it's perfectly engineered to fall right in there to get hopelessly stuck. Fortunately, I've got a magnet on a flexy stick type deal. Wanna guess when I bought it? That's right, the first time I did the shocks when I had 3 of the 4 total rear nuts fall in that damn crevice. Durrrrr.

 

[evilmonkeyMSP]

hehe, i like the layout on the box...that something I'd have to do myself also lol

dont wanna sit there wondering "where does this go???" lol

 

[aMaff]

I saw it on a how to for pulling the tranny (one that is missing a lot of steps, but that's neither here nor there lol) and definitely need to use it. They's a lot of different length bolts and small parts that are easy to lose track of or get out of sequence, so a little tape, cardboard and a sharpie will go a long way

 

[evilmonkeyMSP]

(werd)

 

[aMaff]

So my friend who was supposed to be coming in town won't be here til tomorrow. What does that mean? It means I got down and dirty with some Miata drivetrain. I'm really happy with the progress I've made tonight. Made some unexpected discoveries, and got a lot done.

1. Got the transmission off! Finally!

Found that the front trans seal is bad. There's oil all over the bellhousing. Fortunately I've got an extra trans that's in good shape

Also found that the engine rear main seal is in surprisingly great condition. It looks about as new as my new one. Any better and it'd be still in the bag w/ a part number sticker on it...

So where's the oil all over the back of the engine / transmission coming from? Looks like it's still from where the CAS O-ring went long, long ago. Only problem is that after we (ie kcbhiw lol) installed it, we never cleaned the back of the engine. So is this new oil or old? It's kinda hard to tell. Since it's a $4 part from the dealer, I'm going to go pick one up / order it tomorrow. Rick Case Mazda's like 2 miles from my house I'm also going to clean as much gunk as I can off of the engine so it should be pretty easy to tell when new stuff starts leaking.

2. Clutch
I don't really know what a clutch is supposed to look like, so I may be TOTALLY wrong, but it looks like it's got a really weird wear pattern. The inside is really worn out, while the outside barely has any marking.

And the flywheel:

Any input?

3. Tonight's intended suspension testing
As I posted earlier, I was going to look @ the suspension (fronts primarily, the rears checked out ) to try and cure the bottoming of the wheels in the wheel wells before the shocks hit the bump stop. While it's not a huge deal, the suspension isn't really doing what it's fully designed to that way. Plus, it's rubbing my fender liner. That's kind of annoying mid corner on course lol. A slightly longer bump stop SHOULD cure that. If it doesn't, next season I'll throw some 3mm spacers in there if it's bad enough that I think I need them.

I also never realized how bad I need to shave down my sway bar bushings. I can barely move the thing by hand w/o the endlinks attached. It's supposed to swing relatively freely. Any suggestions on how to do that effectively? Exacto knife? Sand paper? Other?

I think I'm missing a piece...

To get full suspension travel, I just took the spring off the shock so I could easily maneuver the tire through it's full range of travel.

In the process, I ended up taking a couple of really cool pictures that demonstrate just how much camber the unequal length double wishbone suspension on the Miata picks up through compression.

I can has camber?

For comparison on how the MacStrut and double wishbones (though there really isn't any comparison...) work differently through their range of motion:
HS Protege5 - Positive camber

STS2 Miata - Mo negative mo betta!

EDIT: HUUUGE thanks to Michael (autoxes) for his help on this. Having the extra set of hands was instrumental in this getting done in a relatively timely fashion without me totally losing my mind and all my tools lol. Thanks dude! (thumb)

 

[khaosman]

I love that last pic where the wheel is completely tucked in the fender

Did you get your gas-tank evap problem fixed?

 

[aMaff]

I love that last pic where the wheel is completely tucked in the fender

hahaha I know right?

Did you get your gas-tank evap problem fixed?

don't remind me about that. They fixed something, but it wasn't THE problem. I still have no idea wtf is up with that. When I got it back from the shop (abt a 40 min drive) and cracked the gas cap it was hissing for about 5 seconds. I don't know what the hell else it could be. kcbhiw has been kind enough to lend me an old stock fuel pump. I'm just taking shots in the dark at this point. All the sensors check out, all the vacuum stuff checks out. It *SHOULD* be working right. But... it's not.

 

[moxnix]

I was thinking I read that instead of shaving the bushing you could also shim the bushing holder thing if you don't want to grind down the bushing.

 

[aMaff]

the bracket? Yeah, I read that too. I'd have to check, but I don't know yet (haven't pulled the brackets yet to see) how much needs to be trimmed. If it's a lot a couple washers could work.

Is there any issue with trimming or shimming it too much? IE if there's empty space between the bushing and the mount on the frame?

 

[benjpi]

U drive gud, u go fast

Geez, I almost fell of my chair laughing at that one! Autocross is about MONEY. To win, you need prep. Prep costs money.

You want to win on skill & will? Get a bicycle.

 

[autoxes]

or race H/S

 

[moxnix]

Yeah the bracket. I would think it would be ok to be a little off but not to much.

 

[aMaff]

I've got the 'blocks and bolts' reinforcement coming shortly (should've shipped actually), so I'll look at them when I do those.

 

[TinmanMS6]

Geez, I almost fell of my chair laughing at that one! Autocross is about MONEY. To win, you need prep. Prep costs money.

You want to win on skill & will? Get a bicycle.

Sorry, I've run for one season, and that was in HS, so that's basically what it has come down to. In general, though, on a local level, I think that it still holds up.

The problem with your logic is that there are lots of people who have the money to prep a car for a class. Hell, I can prep a car for whatever class you want to name. Driving is still the problem.

 

[aMaff]

Case and point: A Stock this year in our region. Jay won the class, an R compound class mind you, where people DO show up with R comps... on 200 treadwear street tires. It's not ALLL prep (tho it sho does help )

 

[benjpi]

Sorry, I've run for one season, and that was in HS, so that's basically what it has come down to. In general, though, on a local level, I think that it still holds up.

The problem with your logic is that there are lots of people who have the money to prep a car for a class. Hell, I can prep a car for whatever class you want to name. Driving is still the problem.

So, how much to DOT-R's run these days? In HS (the MS6? 225/45R17 BF Goodrich R1's are $220 each, unmounted, at TireRack, so that's $880, NOT including a spare set of wheels) What if you bought the wrong ones? It's great that you've got the money to prep for whatever class, but isn't that exactly the point? I mean, anyone can autocross and have a good time, and learn about driving at the same time. But in the competetive regions, the top spots are good drivers (of course) in trailer queens. So, I guess, u-drive-gud, u-go-fast IS in fact true, but without money you won't get too many SCCA mugs.

/End thread jack

 

[dmitrik4]

it's a combination of both prep and driving ability. you're not going to be able to buy a win in any class; the best-prepped cars don't always win. that's tinman's point. but you're also not going to be able to win in most competitive classes with a halfway or not-prepped car.

in philly, there happen to be some really competitive STS drivers...Cy *could* drive his car to events (and it's been drivien to a lot of events in its life), but towing is more comfortable and reliable. Mike louie drives his car to every event...so does adam koback. tony savini was 7th(?) at Nats in his daily driver, "obsolete" '05 cooper S. he drives to the events, and pulls his tires out of the back seat. all the STS2 miatas are street-driven to the events, usually on the same tires they run on.

bottom line: to win, driving well is a requirement; prepping well helps. i can almost guarantee that someone like eric simmons, corey ridgick, steve snow, or tony savini could cut about about 2 seconds off your time in your car on a 60-second course. dont get hung up on prep and parts; focus on improving your driving.

also, keep in mind...autoX is the cheapest form of motorsports, but that doesn't mean it's cheap.

 

[benjpi]

autoX is the cheapest form of motorsports, but that doesn't mean it's cheap.

Yep. The issue with improving driving is finding someplace to do it: 3 minutes of seat time once or twice a month isn't all much time to improve. But the parts, they suck you in. The first few hits are "free", driving at an AX & having a great time on your MXV4's. Once you look around, you start to see who's got what tires, who's got the "right" wheels, spring rates, shocks, bars, and so on.

Driving well is surely a requirement, but not really exclusive of prep. A national level driver might be able to whip all our backsides in a stock geo metro, but his luck wouldn't extend to the national circuit, where said driver's STS2 miata has been prepped within every inch of the rules (just like the comptetitions).

I'd actually really like to get one of the hot-shoes to drive my car, to see how much I've got to go. For example, the two seconds they could get over me in my car STILL wouldn't have gotten me a podium spot at the last event. So, is it two, three, five seconds? Dunno.

 

[aMaff]

dude, we've got it. Seriously.