tube80z

I have a friend that has the 240SX rears with stock fronts and 4-piston toyota calipers with good pads. We ran the car at several autoxes and it had completely rebuilt stock brakes that we on good shape. Then we changed over to this setup and there was a noticeable difference. We could brake deeper into corners and the brakes were very consistent. The balance for this setup on his car was very good. So in this case it was much better than the stock setup. I will add that the kit he got from MM didn't have any info about needing to change brake lines to make it work. We figured that out when we got into it. A quick search here seems to indicate that it's been a known issue for some time. So be warned. Hope this helps, Cary

So you can't use the trick of a lug nut for a mag wheel? Normally that replaces the spacer shown and makes everything go together easier. Cary

It took me about three events before I started to really like the stiffer setup. After about a year you'll jump in someone elses car and be shocked at how slow to respond it is. Are you sure? Why I ask is if you didn't actually measure you're springs you'll find that they are often off when you measure rate and free length. You may be able to swap around what you have to get things closer. I'm not sure unless you have a lot of development on the car and a really top caliber driver that this will make much of a difference. It gets even more complicated when you start thinking about tire rates too, which vary with speed, temperature, and pressure. Glad to hear you had good results with this. Another convert to the dark side?

I'm not sure this will help or not. I used to have an FIA approved recaro or sparco (I can't recall) and it was composite of some form, probably a high end fiberglass. I can't say the seat was very comfortable at all but looked cool. I think the deal with FIA tests is that it's gone through a specific level of testing and from what I can gleam FIA doesn't like seat back braces. So a lot of the FIA seats are intended for bottom mount only. I currently have a kirkey aluminum seat and I like it much better. I can mount it lower and farther back into the car than the previous seat. There are a number of expensive upgrades that you can buy for these to get halo and additional thigh support. Or if you're handy at fabricating you should be able to do it yourself and save a lot. I don't think this seat has any certification that I can tell. Maybe some of the newer seats do but you'll pay for it. It's comfortable enough with the padded insert but can easily be customized to fit you if you use a pour in bead liner (preferred over the foam). This would you give you a form fitting seat and excellent absorption. This is very commonly done in the formula car and sports racer arenas. Hope that helps, Cary

Since you're in Bend you should check out the autox club of central oregon. Their events are at the fairgrounds in Redmond. Go to http://www.autoxclub.org/ for details and schedule. I will be running a lot of their schedule this year with Paul's old car running with V8 power. Morgan Smith has a 350 chevy in his Z and Dave Kipperman will probably come play at a few events with his new donovan engined car. Cary

Do these cars use bushing compliance to control toe? I know some of the new mulit-link systems use rubber bushings that are very stiff in certain directions and compliant in others. It may be something as simple as that. For a test I'd take the wheel off and mount a long bar to the hub and lever it back and forth and see how much it moves. Then try the other side. It may help to pin point the issue. Cary

I've been looking for that every time I go there. So far nada. One of these days ... Cary

There are a number of options I've used in the past. I bought a nice holesaw notcher and thought it was really good. Then I discovered you don't need a notcher at all and can simply cut two angles on the tube across the center line. And for really funcky angles you can use a program called tubemitre (search google for it) and then transfer the output to a tube and plasma the end off. But the big problem in all this is being able to measure the angle the tubes come together. Take the time to build a simple protractor for tubing and it will save a lot of time in the end. And for the computer geeks there's a program that calculates all the bends and gives you fishmouth diagrams. I believe it's called bend pack or similar. Cary

I won't argue that for most autox has little seat time. But it is racing and HPDE is not. Cary

Hey, at least you used search

A friend did this to a 510 racer years ago. It made virtually no difference to the car and he eventually went back to normal brakes. The only real advantage was people got all hot and bothered about it and it made it into the Japanese magazine Hero or something like that. Only downside is if you lose a half shaft you've lost a brake. Cary

I have a simplified spreadsheet I use. You can pick a target frequency and if you know your weights, sprung, unsprung, and all the weight transfer parameters you can work this out. Measuring the car is usually the most time consuming piece. With slicks we're currently very close to 3 Hz. With the radial atlantic tires we've found 550 springs work for a car in the 2200 pound range. Cary

I'm not a track guru but at hillclimbs, which are higher speeds and rougher courses I haven't had a problem with one inch of droop in the 400 to 500 pound spring range. I run less than that in the front. Cary

Do you ever get the idea they aren't listening to this? Cary

Target has a cheap philips dvp5140 player that is can be made region free. It will play NTSC, PAL, avi files, and a number of other things. $40 was what I paid on sale. I watch WRC videos on it all the time from the UK. http://www.amazon.com/review/product/B000F2KUK8/ref=dp_db_cm_cr_acr_txt?%5Fencoding=UTF8&showViewpoints=1

Because you were interested in the spring rate at the contact patch. My guess is Erik was doing calculations for wheel or axle percentages when setting the car up. Cool, I can't wait to see what you find. Cary

I used to do this all from calculation but I found a really cool method to do a direct measurement on the car. You need to remove the shocks (and what I've done is use a set of old modified stock struts with no oil). You put these in and then then lock the opposite end of the car. Then you bounce the end your interested in. Here's a video of the process in action (bounce test) http://www.racing-car-technology.com.au. What's cool about this process is you get friction effects included and can see how this changes with friction. For a direct measurement of motion ratio all you need to do is measure the change in strut shaft length as compress or extend the suspension. I have a bunch of quarter in AL chunks I use under the suspension to make the change. The ratio is not linear and if you're doing shock work that may make a difference. In general I've found a number of ways to measure the car directly and found this gives more realistic results than calculation. Billy Shope has some procedures based on Miliken's book using scales and a floor jack. You can read about them here, http://home.earthlink.net/~whshope/index.html Cary

It changes the motion ratio.

Yes, Steve and Al. They have a jig at their shop and have done two or three wagons. That car is by far the fastest 510 I've personally driven. Maybe even the fastest car I've ever driven. That includes Kipperman's Z and a few others. A real beast but not scary. Cary

A friend of mine created a bolt-in 4 link conversion for a 510 wagon. It was developed for high HP 2-door cars. The difference between the 4-link and the trailing arms is amazing. Unfortunately this isn't offered for sale. It was on a yellow 510 with a turbo KA that was at Shasta a few years back. In case anyone saw it. Cary

Maybe/Maybe not. A long time ago I measure the CG of a VW supervee (using the flat motor) and a formula ford. The Ford actually had a lower CG by a small amount. If the Subies have the crank about center of the motor and you can get a normal engine lower than this it may be able to have the same/better CG. The engine is pretty light from what I've heard and being short will help the car turn better. For SCCA classes you may be able to use the exhaust clearance loophole to trim the frame rails for this to fit. Then use a cage to put the structure back in. Rear steer and forward mounted TCs would fix the suspension issues assuming you keep it strut based.

I'd guess C4 suspension. Benefits would be reduced scrub and better camber control. Downsides could be reduced torsional stiffness in the chassis if this wasn't done right and more than likely the car hasn't been setup. I think there's some gain to be had doing something like this but it needs to be balanced front to rear or in the end you'll end up with a lot of work and not much payoff.

Not easily, a few swaps have been done like this over the years. The straight axle is actually better. Check dimequarterly for info.

A spherical on the end of the arm could attach to a double eared bracket on the strut. You could do that in such a way that you could use stock or the new option with the same struts.

Since that's what most people run on the front for a tie-rod setup I don't see why it wouldn't work on the rear. Cary