tube80z

You missed a very important one. TLA -- three letter acronym. Cary

I guess technically it didn't fail. As the car left the road it hit a tree left in the side. I've attached pics below. What you can't see from the pics is the car rolled onto the tree and the weak spot was the rocker, which had no tube running along it. It folded in along with the floor breaking the drivers leg/hip in multiple spots. The door bars where nascar style and you can see how folded they are as well. This car was a beast and left the road a very low speed comapred to what it could have been going. If the bottom of the rocker had been reinforced I think the driver would have been able to walk away. Cary

The adjuster I'm thinking of is a shell. On the outside is a set of threads and on the inside is another. One set are right, the other left. This allows the unit to operate like a turnbuckle in a very limited space. The toe-adjuster was shown on another pair of fabricated arms in one of the threads where rear arm options were discussed. Hope that helps, Cary

No, by toe-adjuster I'm talking about a specific piece that has left/right threads sorta like a turnbuckle. I do agree once this is set it isn't that likely many people will be changing it. Cary

The adapters that John has will be stronger if they are held in a couple of places. I think they could be welded into the stock arms. The tube idea was to simplifiy the fabrication and make the arm stronger. It's a lot easier to use a holessaw on square tube and mount the adapters and then weld this assembly to the arm. In the pic below the yellow bits are square tube and the red bits the adapters welded into it. You can see how this part bridges the tubing of the stock arm. If you use a toe-adjuster or better yet a threaded bushing with left/right threads you have adjustement on the car without taking anything apart. Cary

That's pretty close. The 8500 limit was for an L24. And as Paul mentioned it wouldn't hack much beyond that wihtout becoming two pieces. We even tried the nissan comp forged crank and had similar results. The ultimate solution we went with was to drop the rev limit to 8250 and call it good. When we switched to an L28 we called nissan comp and they indicated 8K would be about the max. So we went to 7800. The generall warning sign of a broken crank was a clutch pedal that jumped when you pushed it in and the flywheel would fall off when you took the motor out In almost all cases the front pulley bolt could be removed by hand after this happenned. If you lose something on one end the other takes a serious beating. Cary

The other news is the 8611-1259 double are now supposed to be digressively valved. Cary

The other news is the 8611-1259 double are now supposed to be digressively valved. Cary

I have some arms I'm going to eventually modify for a friend. I was looking at them last night thinking about ways to do this. I thinking I'd cut the arms across the flat plate and weld on a piece of square tube. This tube would be hole sawed to hold the heim adapters Jon showed further up the thread. Not sure that makes sense but it's clear in my head Cary

I race wtih a guy that uses this setup in a pickup truck, an extremely fast pickup truck I might add. He's running similar levels of power and using sticky tires. He's not had any problems with axles but has blown up a number of the LSD units. As far as dragging the tail that will have a lot to do with the geometry of the suspension. You'll probably need to build in some anti-squat. Cary

Hi Mark, Here's an old thread with some info that may help you. One big item to think about is tires, will you run slicks in prepared or a street radial for SM. That will make a difference in picking rates to go with. For let's start from the beginning: 4) car set-up as per John Coffey: Camber - 3 degrees neg front and 2.5 neg rear (fine tune with pyrometer). Some tires need more insided temp to work correctly but in general will be 10 to 15 higher (slicks) and may be even higher for radials. Caster - 6-8 in front (you can decrease camber if you have more caster) General rule of thumb is one half KPI (steering axis inclination). When running this much caster you also need to check to make sure you don't have too much caster trail (mechanical trail). You'd like to have around half an inch. Also try to have no more than 20 percent of tread width as scrub. Toe - 1/4 to 3/8 out in front and 1/16 to 1/8 in in the rear For tight track try rear toe out. Ride Height - 4.5 to 5 inches at the rocker (don't try to over lower the car) Springs - 400 all the way around (ideally should be set based on scale weights and multiplier for tire type -- perhaps another discussion). You'll need proper shocks to make this work. Helps to quicken transition times and keep suspension geometry for going all over the place. Sway bars - 15/16 to 1-inch front and 5/8-3/4 rear -- both need to be adjustable and connect to the strut, not the control arm. Sway bar should be in a low friction mount, which is not poly or other form of pinch block. Ideally at least one is driver adjustable for when you need to make the last minute tweak between runs. See what Jon has been doing for an idea of a low friction mount. Offset bushing - yes Will be needed for street prepared but should be avoided in other classes. Never use Poly suspension bishings, it has too much friction. These need to be low friction pieces to help with mechanical grip. Good advice on notes deleted(lookup the original thread). A tire pyrometer is good to indicate wear but not a lot more. But tire pressures are more accurate on how the tires are used. You should work on a setup that gives you an even rise in pressures. This is where good notes and understanding what you need for a hot tire pressure is important. You can switch to nitrogen to help eliminate the effects of water vapor in the tires. To adjust chassis balance you can change the rake. Rule of thumb is two turns of the spring collar to start. If the effect is too much try one turn. You lower the end that isn't sticking. Make sure you keep the arms near lever and don't end up too low. The car should be corner weighted. Make the front level and the front weights as close as you can and live with what you get in the rear. Move as much weight down and towards the back as you can but not behind the rear wheels. Remember you need to make ride height changes to compensate for weather conditions to keep a balanced chassis. Also consider using shims for camber/caster plate alignment. These allow rapid known changes and/or allow you to get the car put back together without having to do a major alignment. Before an event always know all your settings. Keep notes of any changes that you make at an event. And at the end of an event do a setdown. This last step is important and few people do it. If you're using the same size tires all around keep notes on how hard they were used and rotate to keep the use as close to the same as you can. Do all chassis setup work on old tires (but not junk). New tires will mask a lot of the changes until you have killed them. By doing all this you'll end up having a car that is kinder to its tires. A number of assumptions have been left out of this thread, like bumpsteer, corner weighting, checking for compliance, suspension binding, etc. Test, test, test, and have lots of fun. Hope this helps, Cary

Take a look at the second pic at http://picasaweb.google.com/tube80z/Parts The inner is unscrewed the rack end drilled. If it still doesn't make sense let me know and I'll try powerpoint cad again Cary

Why not cut as shown and then mount the adapter in some squaer tube and mount it straight on the control arm. This could easily be welded up and takes care of the angle problem. I'd do something similar on the inside too. Cary

Remove the inner tie-rod ends, chuck it in a lathe, and drill for a standard size bolt. Then build a clevice out of steel (drill a few holes, band saw, then dress with a grinder) that you bolt to the rack. This clevice will hold the rod end. Below is a pic of one way this can be done (not really a clevice). Cary

Jon, those look pretty good. Cary

The tie-rod part won't fit in the tube? A couple of options. You can slit the tube with your grinder lengthwise and see if that will let you slide the tie-rod part in. Or you can do a simple butt weld to hold the pieces together and use a piece of tubing that goes over both for the final weld. Cary

If you're looking for a single thread that sums up everytyhing that I've seen on Ackmerman it is http://www.clubracer.com.au/articles/ackerman.asp Cary

This is far more useful http://www.clubracer.com.au/articles/ackerman.asp Cary

Since this is just a Jetta why not use JB Weld. You'll need to clean the crack/hole and make sure oil doesn't drip in. My trick is to hook another car to the PCV line and generate low pressure in the engine. This will keep oil from coming out when you put the expoxy on. Seems to work well for quick silocone repairs too.

Aren, Did the compression ever get fixed before you ran the motor? I had heard, perhaps incorrectly, that you had a hole that was well down compared to the others. Did this just happen, or did you have a stuck throttle and this happenned. I've heard a couple different versions. I had a similar problem where the cam dowel sheared and all the valves hit the pistons. In my case none broke like this but all my valves were bent and a number of guides broken. Cary

The car belongs to Dave Kipperman and he built it about three years ago. So you were well ahead of him. I first saw it in the mid 80s at a shop that built convertables. No, can't say I did. Many people have built similar but I haven't seen any as a bolt on kit from a company. Cary

I just make my own. I've never seen panels that have flanged holes. Send me an email and we can chat about it. Cary

I've been using the gussets from Joe's racing products. They are 0.065 (16 guage) if I recall correctly, which is essentially sheet metal. The hole isn't necessary but would save some weight. These need to be thin so if the joint is loaded in compression the gusset buckles before the tube. And in tension the larger surface area is better. At least that's how it was explained to me. Cary

I chatted with a friend who's a civil engineer and he gave me an answer but wanted to check with a friend that's a structural engineer. They both agreed a single gusset in the middle of a tube is a bad idea. If the joint is in tension or compression there will be more stress in the middle area (top and bottom). You'd be better off with a gusset that captures the neutral axis where stress is least. Both agreed a formed gusset (what I call a taco gusset) would be the best solution. Are they in agreement with your engineering friend? The explanation made sense to me. But I'm far from qualified to give a real answer Cary