JMortensen

That's it right there. Here's the kind of control arm you could adapt in to fix: http://www.partsgeek.com/gbproducts/WC/120-01117160.html?utm_source=google&utm_medium=ff&utm_term=1985-1986+Porsche+944+Control+Arm+OES+Genuine+Front+Left+Lower+85-86+Porsche+Control+Arm&utm_content=YN&utm_campaign=PartsGeek+Google+Base 944, RX7, and I think BMW 3 series all uses this kind of setup (and probably a LOT of others too) A bent TC rod would work, but a bent TC rod would be weaker than a straight one, so you'd want to oversize the material and make sure that you upgrade the fasteners on the control arm side, and you couldn't use a turnbuckle to adjust caster unless the turnbuckle was a real small one at the back end.

The problem is the tension compression (TC) rod. It connects to the inner ball joint bolt holes, so even if you lengthen the control arm, you don't get it away from the TC rod. Gollum has the right answer, SLA would fix the problem, as would a 944 or RX7 style control arm that is shaped like an L. Ours, if you look at the control arm and the TC rod, essentially is shaped like a right triangle. Once you got the control arm issue out of the way then you'd need some modifications on the rack to give it more throw. You can probably find a rack out of a different car that has more than 5" of stroke like the Z has, or you could make a shorter steer knuckle (the shorter you go, the harder it will be to steer).

Doesn't go all the way through the material. So in the case of the ring gear the hole might be 3/4" inch deep, and it's threaded all the way down to the bottom. Basically means that you can't tap it because the real threads on a tap don't start until 3/8" or so up the tap.

The blind holes with threads are in the ring gear. If you're talking about putting a helicoil in the ring gear threads to make them 12mm, I don't think that you could get one that would only step down 1mm, but even if you could, I wouldn't do that on such a crucial fastener.

13mm bolt. 12mm hole. That's if I'm right, and I might be totally wrong.

I think you're right about the VLSD having 30 splines vs the normal 29, but the diff stubs should swap out no problem. The issue with the bolts is that the ring gear has the threads, and it's a blind hole. Can't tap it, and the metal is hard as hell anyway. I think I've read that some of the shortnose diffs have 13mm bolts. That's really fuzzy, so someone with experience should really say for sure (again, I think SATAN has some experience here and that guy knows his stuff), but if you have a 13mm ring gear hole and a 12mm LSD, then you can't get the bolts through the LSD and into the ring gear. It would probably be a fairly easy task for a machinist to open up the holes if that were the case.

Probably the return line or the vent line from the tank. http://www.classiczcars.com/forums/showthread.php?33873-Fuel-Tank-Vent&p=286839&viewfull=1#post286839

Hmm... that must mean that it's a serious PITA. There is another option. Get some aluminum fuel line (or anything else not stainless steel) and the cheap flare tool.

Yes, and besides, most places won't accept returns on tools for just that reason. Splitting ends are possible with any tool, not just the cheap ones. http://www.summitrac...rts/SUM-900311/

The much easier thing to do is swap the LSD into the diff that already has the gear ratio you want (assuming they swap--don't know much about the shortnose units). You might try asking SATAN. I think he knows quite a bit about those shortnose units.

It's nice to have a dedicated race car. No compromises. Street car sounds pretty sweet too. Good luck with them.

You can get an AN flare tool from Summit. They have a cheap ass Chinese tool and a nicer American tool. I didn't intend to do hundreds of flares, so I bought the cheap one. I did my fuel and brake system plumbing and only had to redo two flares on the whole project. Works fine for me, I bet it would work fine for you too. The one thing I've read about stainless is that if you use a regular tubing cutter you can work harden the end and then it's more likely to split the flare. Someone who has some actual experience with stainless might help out more with that problem or tell you that it isn't a problem at all. EDIT-Coffey told me to buy a magnifying glass and check each flare. Good advice. One of the cracks that I found was really hard to see without it.

Looks really nice Mark! Unless you're planning on packing the rear of your car full of stuff, I'd suggest when you redo the rear brace you have the clevises cut off and weld the brace in. I had a straight bar with rod ends and I didn't weld in a bar because I thought I would want to remove it at some point. Turns out I never removed the bar, even when I drove to the track with 3 tires in the hatch along with my tool box, helmet, and jack. 4th tire rode shotgun if you were wondering. Besides if you welded it in then you could use those rod ends for some new LCAs.

I'm using rod ends on the control arms so I had to make new spacers anyway, and this meant that I wasn't concerned with the inner dimension of the crossmember. Since it is easier to weld on the outside of the crossmember, that's where I did my modifications. I haven't talked to anyone else about the bumpsteer figures. I think I might be the only person who has a slotted crossmember though. Maybe Pete Paraska has one too. Not sure, I know we were both talking about it in 1998 or 1999. I know there was a lot of concern when I initially did it that the adjustment would move around. Never happened to me in about 40K miles and 8 seasons of autox and a handful of track days on the previous crossmember. It would also be pretty easy to weld the washers to the crossmember once the happy spot was found if that was a serious concern.

Here you go.

The amount you lower the car won't change how far the bumpsteer needs to be adjusted. If you're thinking roll center, then I'd suggest roll center spacers (aka bumpsteer spacers--but they really don't adjust bumpsteer). More info here: http://forums.hybridz.org/index.php/topic/38615-bumpsteer-faq/

Here you go.

Not a big fan of the 3/4" up and 1/4" out because on my car 7/16" up got rid of the bumpsteer. 1/4" out has a minimal effect on camber, but is not really doing much of anything else. As to how I got the hole straight up, I just laid a square on the table and marked it and then eyeballed it a couple times to be sure it was as close as I could get it. When I did this I found that the rack was 1/8 or 1/4 lower on one side, so the tolerances are not super tight from the factory and it isn't necessary to be down to the .0001 on these.

He's talking about the angle that the wheel turns at. On a Z you have 36 degrees on the inside wheel and 33 on the outside wheel at full lock. Any farther an the tire will likely hit suspension pieces.

I'm trying to follow how side load on the case, which this is what makes this thing work, caused the pinion bearings to fail. This is especially strange when they're left loose in other helical LSDs like the True trac. Are you sure it wasn't something else, like the washers got chewed up and the metal floating around in the diff took out the pinion bearings? Which bearings went bad? The pilot ball bearing, or the tapered bearings? Pictures of the LH side gear chewing out of the case? I'm just not getting it.

Looks like the parts are shipping to me next Tuesday, so I probably won't get them until the end of next week or the beginning of the following week.

Seems timely as I just brought it up on another post, but here again is Neil Robert's suggestion on how to test bias, which doesn't require flat spotting tires: http://forums.hybridz.org/index.php/topic/99500-tail-wagging-under-hard-braking/page__view__findpost__p__932930

If memory serves, Dave is using this caliper: http://www.wilwood.com/Calipers/CaliperList.aspx?subname=Billet%20Narrow%20Superlite%206%20Lug%20Mount so the piston diameters would be 1.62, 1.12, and 1.12. I think the Toyota calipers had staggered pistons as well, would need the diameters there to get a comparison.

Larger rotor diameter is in effect a bigger lever, so the same caliper will have more effect on a larger rotor.

It's all here. The short version is that prop valves aren't actually proportional, so if you put one in the front, the harder you stepped on the brakes the more rear braking you would get. http://www.stoptech.com/tech_info/wp_proportioning_valves.shtml