JMortensen

You do some nice work, weedburner. Been admiring your album...

Nice fab work, but no need for the heavy solid bar in this application.

I think AZC now has a parking brake option. Regardless, I don't think you're going to get your current system balanced, so going bigger in the rear is going to be the solution. Might check into some of the other options. Silvermine? The basic idea in autox is to keep the tires happy. On a more stock suspension, there is too much body roll and/or too little camber to prevent the tires from rolling onto the sidewalls. One very rudimentary test is to take some white shoe polish and dab a little on the corner of the tire and over onto the sidewall in a couple spots, then check after a run and see where the polish is worn away. Yours is obviously not stock, but we also don't know what adjustments you have available from your description. With no adjustability all you can really do is pump up the tires more. With adjustable camber you can lean the tires in, and with adjustable caster you get more neg camber out of the outside front when you turn. jhm's suggestion of used slicks is what I run. A formula atlantic front fits a 15x10 and you can find them cheap online as he said. The problem with going to a sticky tire is that you increase roll, and the tires aren't as durable as a street tire. So you're faster, but you'll also find the limitations in the suspension as well. My Z was sprung too soft so I had way too much body roll. After a season my slicks looked like worn out skateboard wheels, visibly cone shaped due to the wear on the outside. I run the Toyo R1R on my Miata and I love it. It sticks great, really good in the rain, etc. I have found that I can overheat it even at autoxes and badly overheat it at practice and schools, and when they overheat they lose grip, and if you make up for it by turning the wheel more, it tears up the treads. Many guys around here spray their tires with water between runs. It's really necessary on the R1R IME, but still a really good autox tire. I suspect there are better choices if you want to do track days too.

They are the shit though. We have a really competitive local SCCA autocross at Packwood, and the surface is bumpy as hell. Almost all the fast Miatas are on FCM. I think I'm going to get him to do my Z struts when I do another set.

Based on that I'd suggest bigger sway bars and a larger rear brake kit.

Are Vettes still mouth breathers? Used to get air from under the nose, and the air dam directed the air up into the rad.

Man, that airdam on the bottom of the splitter strikes me as a really bad idea. I suppose they probably have a high enough ride height that it wouldn't do anything anyway, so the get the look of the splitter and the cd reduction of the airdam. Then on the hipo version it actually looks right, so that one must either be low enough to use it, or at least you could lower it to be useful. Interesting to see the different shapes on the undertray. Would still like to try my idea from p1 on this thread and make a venturi under a flat tray...

How serious do you want to get?

The 10AE is the same way, all the options like yours but I have a 6 speed and a shorter rear gear. Still got my doors blown off by a Kia minivan getting on the freeway... LOL. Lots of shock options too. Have you decided on that yet? I'm trying to keep mine cheap, thinking Vmaxx.

What kind of Miata? I bought a 10AE a couple years ago and it sucked up all of my Z funds for about a year. Slow car, but definitely the most fun to drive car that I've ever owned.

Or, go down to the local auto parts store, buy a 1' piece of bubble flared brake line, cut one end off and put the correct fitting on and double flare it and pocket the other $230 + s/h.

Certainly sounds like the faceplating will give you faster shifting, and you already know that the stock clutch and flywheel work. Light flywheel might be nice too but sounds like it might not be necessary to get the faster shifting you're after.

Thanks for that. Does "BF" mean "bubble flare" as you would find on BMWs? You know that's different than double or inverted flare that was stock on Datsuns, right?

Never seen a metric Wilwood prop valve. Didn't see it on wilwood.com either. If the fitting is right, check the flare for cracks with a magnifying glass. Just re-read. There should never be any play in the hard line. You're not tightening the fitting all the way down. Brings us back to the threads, I think.

I can help a bit with the button clutch. You've got 2 diameter options, regular diameter flexplate or the smaller stuff. The smaller stuff reduces the OD of the bellhousing and allows you to mount the engine and trans lower in the chassis. I don't know if you are looking at new drivetrain mounts at this point, but that's what it would take. The oil pan hangs down lower than the bell housing, so you'd need to do something about that too if you really wanted to get the thing lower. For just a button clutch, you can run a flexplate from an auto and then a button clutch. I bought an ACE 7.25" dual clutch and found that it did not work with the stock flexplate off of a 5.3, so I had to get another flexplate from Quicktime which had a flat mounting surface. I also got the wrong throwout bearing from QM and had to return it and get the Tri-Lite that Cary mentioned. There are always multi-plate clutches on ebay. You can get NASCAR takeoff triple clutches from Tilton for about the same price that I bought the ACE. I got a double because supposedly you can slip it "a little bit." Really though, these clutches are pretty digital and not meant to slip at all, and things like pulling the car onto the trailer are going to ruin the clutch. You will HAVE to winch it on the trailer regardless. I just figured that a double might be a little bit easier to get the car from the grid to the starting line when autoxing. I think just going to a plain 'ol light flywheel would help the shift speed, but doing the flexplate button clutch should enable the engine to wind down MUCH faster which should improve the shift speed a lot (I know going to a light flywheel on the L series helps quite a bit). Related thread here: http://www.corner-carvers.com/forums/showthread.php?t=47895

This really is a side track, but I'm not convinced that the R230 is any stronger than the R200, and it comes with all the headaches associated (CV shafts have to be pieced together, etc). Get an R200, run turbo shafts from Z31 or S130. If you break that, do a Ford 8.8 would be my suggestion. Nobody has a bolt in option for the Ford, but that's where it's at IMO. R230 is a waste of time/money. My $.02...

Found the flaw in my procedure with the help of Facebook and another forum. It is possible to have the angles of the trans output shaft and diff flange correct, but still have too much U-joint angle if the trans and diff are too far out of line from each other. So I went back and measured and found that the trans and diff are about 13/16" apart, and the distance from the trans output shaft to the diff flange is 23 3/4". Looked at an old Datsun driveshaft and it looks like about 3 3/4" is taken up to get to the center of the U-joints. Just went ahead and guessed at the CTC of the driveshaft U-joints will be something like 19". Plugged the math into Google: arctan(.8125/19) and got .0359 radians. Converted to angle and got 2.05. I believe each U-joint takes 1/2 of that, so I'm right at about 1 degree, or just about perfect. Does that sound right?

You might try the shifter bushings. They're cheap and may help some. I'd also give good fluid a try. Your situation is sounding less and less like what happened to me and my friend. Our transmissions shifted fine, but on 3 separate occasions they actually locked the rear tires solid, because the trans fully engaged 2 gears at once.

Sounds like you're referring to bearing slop, and the pinion pushing the ring gear away as you accelerate. I guess they're calling that runout, but I think you'd have a hard time measuring it unless you put a prybar in there and pried one way and then the other and measured. I know you can get a late model Subaru R180 with 3.54s, you'd have to switch over to the screw in buttons as described in the big diff FAQ post. I would think that since the 3.54s came in the automatics they'd be the less heavily used option, and I'd definitely take a shot on a $50 diff to see if that fixed it before going through all the hassles and expense of replacing bearings.

Back at this again. Got the height figured on my engine so now I can concentrate on the trans mount. Here's a video of what I did. I think I'm close enough but would like to hear about it if I'm wrong. http://youtu.be/bVCPZOfXsaU

Re the clunk: http://forums.hybridz.org/topic/105207-the-dreaded-diff-clunk/ "Runout" is usually a problem when the carrier or the ring gear isn't true. If runout were a problem, I'd think you'd have a womp-womp-womp noise, not a whine, because the ring gear would get closer and farther away from the pinion. Runout in the pinion would be if the head of it was bent and I think that would be quite a bit less likely to find. A runout issue is also not something that is likely to happen after years of driving quietly. Runout is an assembly or machining error IME. I could see if the bearings are really worn how the backlash could change, but in my mind that isn't runout, it's slop in the bearing. With respect to your questions: 1. Yes. You can change carrier bearings without messing with the pinion bearings. 2. Next to nil, and unless the carrier shims are within a couple thousandths, this would have caused major problems a long time ago. 3. Yes. Shims shouldn't change if you use the same bearings, because the new bearings should be the same size as the old ones. 4. I changed the bearings an an R200, the result was that my wallet was $500 lighter and I didn't gain anything from it, but I somehow convinced myself that I needed to change them since the diff came out of a junkyard. I would suggest that you buy another used diff in good condition. It will be a lot cheaper than rebuilding the one you have. If you want to change bearings, I'd suggest you pull the thing apart and just look at the bearings and races and change the ones that have scored or pitted bearings or races. I think the likely cause of your problem is pinion bearings. Here is another resource for noises: http://www.ringpinion.com/TechnicalHelp/ContentFrame.aspx?FilePath=~%2fContent%2fHowTo%2fGeneralInfo%2f%2fDiagnosing_Noise_(Part_1).inc http://www.ringpinion.com/TechnicalHelp/ContentFrame.aspx?FilePath=~%2fContent%2fHowTo%2fGeneralInfo%2f%2fDiagnosing_Noise_(Part_2).inc

12x1.5 is a more common size than 12x1.25. Toyota, Mazda, I believe Mitsubishi, the Camaro, etc all use this size. You can buy generic lug nuts for both sizes at the auto parts store. I just bought some for my Miata when I took the wheel locks off. Not a problem. You can get aluminum splined nuts for Miatas all over the place.

The strut and control arm are designed to operate perpendicularly. There is no mechanism in the control arm from the factory to allow the strut angle to change because it is an H arm with level inside pivots; it's just designed to go straight up and down. If you run the strut at an angle, the angularity increases as the strut compresses. This puts a lot of side load on the strut itself, as well as a twisting force on the outside of the control arm. Maybe bushings will compress enough to make up for that, but it's putting some amount of force (which I would think would be pretty considerable) on all the suspension parts back there. I don't know what TTT did on SunnyZ's car. If they did something to keep the strut perpendicular to the control arm, then it might be fine. Maybe the moved the strut housing in relation to the hub. I think they could do that with their own proprietary uprights that they make. Some people are making control arms and advertising that you can shim the wheel back in the well. I think AZC says that about their stuff and I want to say someone else does too, but I can't remember who. Regardless, it's a bad idea. If you do an A arm and toe link, then you can rotate the strut without putting any strain on the strut and arm, but you would have to run it through from full droop to full bump and make sure that nothing was binding within the range of travel. My own A arm and toe link binds after just a few degrees, but I wasn't trying to move the wheel, I was focused on getting rid of the stiction of the bushings.

Yes, you'd need to move the strut tower back in the chassis. If you just built an arm to move the strut back, then the strut would get less and less perpendicular to the control arm as the suspension compressed. Not good.

ARP 2.5" studs from a Camaro or 2nd gen RX7 fit, but they have 12x1.5mm threads. Quest vans are a little shorter and have 12x1.25mm threads. I'm sure you can find part numbers with a search.