johnc

Currently side skirts are used to keep air on the sides of the car from spilling under the car if you're generating a low pressure area. Lots of people think the skirts are there to keep the under car air from spilling out, but always remember that air flows from high pressure to low pressure. If you are generating down force from under the car then side skirts are needed. If not, then you're just adding weight.

Way back when I had an old 1967 Sears service van like this (but Sears green with no windows): It had a 440 magnum with a 727 Torqueflite, a narrowed rear with 4.56 gears, a Mopar LSD of some kind, and N50-15 Positraction Torque Twisters on 12" wide steelies with dog dish hubcaps. Woudl run 13 flat in the 1/4 mile. I even left the ladder rack on top and had a ladder strapped to it. Stole a green Sears service technician shirt witht he name Greg on the left pocket. Won a pretty good amount of money with it for a few months until the SoCal locals realized that it didn't have a 273 V8 with turbo muffler.

The original question is so vague that its unanswerable.

Might as well buy direct from Stahl. My price is the same as theirs.

Well... my post was about an idealized business that works efficiently and wants to make money. I agree that most businesses don't work that way.

No custom wheel maker I know will build a 15 x 10" or 12" wheel with 1" backspace. Most won't build one with less then 33% of the total wheel width as backspace due to strength and safety concerns. You better call whichever wheel manufacturer you're thinking about and talk with them a bit.

Its all about how much money a shop can make doing "X" over and over again. Once you get the process down the margin on doing "X" increases and its the big money maker. The more people in your shop that are doing "X", the more money the shop will make. If you have to take someone off doing "X" and have them do "Y", the margin on that person drops significantly. The only time you want to take a person off "X" and put them on "Y" is if there isn't enough "X" for that person to do. Your bid of $500 tells me that they don't want to media blast your engine compartment without actually telling you that. The shop figured that if they have to pull a person off "X" for 4 hours then the margin on your media blast needs to be greatrer then their margin if that person was kept on doing "X". Make perfect business sense to me. You're never, ever going to be happy with the job they do because you feel they are ripping you off. They are not.

That's good news. I guess they couldn't get anyone to purchase the fixture and extra tubing.

From the latest Mark Ortiz newsletter: FRAME TORSIONAL STIFFNESS Recently I was asked to assess a northeastern dirt modified car which has the tendency to consistently crack one particular welded joint in the tubular plus 2 x 4 mild steel chassis. Attached are two bitmap image files from the two leading northeastern modified chassis builders [not included here as they are copyrighted catalog images] . The car in question is not one from either of these builders but is essentially the same in design. It is actually designed to be more flexible, or that is the claim of the builder. I must confess that even though I have worked with these types of cars recently I had never really taken a step back and studied just the 'naked' chassis structure. All I see is a 'wet noodle' that only resists torsional loads on the sheer size of the material used. The 2 x 4 frame rails are required by rule but the rest of the chassis is just a 'stick built house'. So my question to you is why do the folks who build and race oval track dirt cars still insist, rather strongly, that a flexible chassis is the 'hot ticket' to get the car to turn in to the corner? That is the claim I hear the most in defending flexibility. I was trained to believe that you go as stiff as you can go up to the point of incurring a weight penalty and adhering to the required safety rules. The claim is that the flexible chassis is easier to tune. I agree because to me it is to a certain degree un-tunable with an undamped fifth spring doing the work. The only drawback to going as stiff as possible with a dirt car chassis that is required to use a beam axle front and rear is that, in my opinion, it would narrow your setup window and in effect, yes, be a little harder to zero in on a fast setup with just springs, shocks and anti-roll bars. One additional piece of information: the engine is not used as a structural member and in fact besides the engine plate which fills the bay below the A-pillars, the mounts are designed to promote engine movement as well. I really need a sanity check on this one. What is my counter argument to the 'flexi' folks? The frames shown could be less triangulated than they are, actually. Dating from carriage building, vehicles with beam axles at both ends have used torsionally flexible frames with decent results. Most trucks are still made this way. They don’t even use poorly triangulated space frames; they use channel-section ladder frames. The stresses in the frame rails are such that they are heat-treated, and frequently carry cautionary labeling discouraging welding on them lest the heat treat condition be altered. Some people may be convinced that there is a performance advantage in a torsionally flexible frame, but another reason frames aren’t triangulated better than they are is packaging. The diagonals required are hard to find room for. Things like the engine, the driver, and the exhaust system tend to get in the way. With more diagonals, the car becomes harder to work on and to get in and out of. I am not convinced that a torsionally flexible frame is an advantage, for turn-in or otherwise, but with softly sprung beam axle suspension at both ends, it doesn’t make much difference because the torsional loads on the frame are small. A torsionally flexible frame does make the total chassis more warp-compliant, but as the questioner notes, the compliance is largely undamped. Excessive torsional flexibility can give rise to torsional oscillation. One commonly accepted rule of thumb is that for the suspension to work as it should, particularly as regards damping, frame twist should be no more than a tenth of the total compliance in the warp mode, suspension and tires included. With an existing car, we can test this. We need a flat support to place under one wheel, or alternatively two of these for two diagonally opposite wheels. These should be large enough to fully support the contact patch, and tall enough to create significant suspension displacement, yet not exhaust the suspension travel at any corner of the car. When we set the car on the support(s), we create a known displacement at the contact patches. If we are working in inches, we can get this in angular terms by dividing 57.3 by the track width, then multiplying by the height of the support. Alternatively, we can measure the angle directly with a long straightedge and an angle finder. If we do this at both ends of the car, the angular warp displacement is the sum of the front and rear displacements. We then know how much warp, twist, or cross-axle articulation we have at the contact patches. We can measure the frame twist by measuring angle from gravitational vertical or horizontal at any reference surfaces at the front and rear of the frame, first with the car on level floor, and then with the car on the support(s). The change in the front/rear difference is the amount of frame twist under the load imposed. The frame twist should be no more than a tenth of the warp at the contact patches. It will be apparent that stiffer springs, bars, and tires will call for a stiffer frame, to meet this requirement. A suspension that uses high roll centers to get its roll resistance, rather than relying on the springs and bars, will not require as much frame stiffness. Is a car with a flexible frame easier to tune? Well, it is less responsive to changes in springs, bars, and even roll center height. It is therefore less prone to being overly touchy to small adjustments, but cars with compliant tires and soft suspensions tend not to have such a problem anyway. Indeed, even pavement cars with really stiff suspensions are also more often under-responsive to changes, due to insufficient frame stiffness, than over-responsive due to excessive stiffness. A flexible car will respond differently to changes in track conditions than a stiff one. That doesn’t necessarily mean it will change less, but it won’t change the same as a stiff car. If the car corners on three wheels, like the one we discussed last month, frame stiffness does not affect wheel load distribution, past the point of wheel lift.

Thanks. I suggest you begin and end your day with something other then HybridZ...

As Jon mentioned above there isn't really a safety issue. You'll get to the point that the LCA will bind so tight you will have very little suspesnion movement. With urethane LCA bushings I won't run more then about +4 on caster.

My guess is that Tokico put the HZ3013 spacer in the HZ3016 box. The 3013 spacer is for the 280Z which has a longer rear strut tube then the 240Z. The shocks themselves are identical. You will have to cut that spacer or make your own of the correct lenth. You want the top of the shocl body to be flush witht he top of the strut tube. The gland nut shoudl tighten down on the shock and not bottom in the strut tube threads. Tokico should have included a large ID, small OD washer that fits on top of the shock body and inside the gland nut. That is used in case the shock is a little too low in the strut tube. And the issues you're having probabyl have more to do with Tokico and not the 240Z. But, here on HybridZ we modify the hell out of these cars so these kinds of issues are almost normal. In most cases we just measure, cut, weld, and make it work without even bothering to post anything. That's why you're getting a little bit of crap from us. Hang in there, this is one of many rights of passage for a 40+ year old car that has a limited aftermarket.

$800 is cheap for a custom oil pan.

And as of the end of 2011 you're not buying Tokico products from Tokico anymore. In the USA they are being sold by a fullfillment house called Belshore, Inc. They dont' know dick about cars and just put stuff in boxes. That stuff can be Tokico shocks, Salad Spinners, Snuggies, or buckets of Oxyclean. It doesn't matter to them.

Ok... lots of confusion here. The "strut" is the physical tub and casting that's part of the suspensiuon. The "shock" is what goes insdei the strut tube. The shock has to be the same length or shorter then the inside length strut tube. If its shorter, you just make and install a spacer that goes in the bottom of the strut tube to position the shock at the top of the strut tube. 1.5" OD tubing is what you use to make the spacer. And, as Leon mentioned, with knowing the Tokico parts number, you're not going to get much more help frmo us. Look on the side of the shock for the part number.

Ths thumbnails in the thread above open just fine for me. Firefox 16.0.1 with the lattest java updates.

Check the Announcements section. Big problems with the site.

Hacked and mal-ware dumped onto almost every page. Dan's been working to fix it since Friday. GoDaddy sucks ass as far as ISP support. IPB has been awesome helping Dan fix the issues and getting the site back up. We currently have a number of file permission issues that Dan is working through using his iPhone at work. That's gotta be a nightmare.

Coast Fab: http://www.coastfab.com/mufflers.html

As mentioned above, if you're drag racing the cage is fine. If you're planning on doing road racing, track days, autocross, etc. you need a diagonal in the main hoop. I suggest those door be redesigned into X or a NASCAR style and the main hoop rear braces should go to the strut towers to help reinforce the chassis. A second reason the main hoop rear braces should not go to the back of the car is that you need the crush zone in case of a hard rear impact. Those braces, as installed, will transfer much more impact load into the cage and into you. They should also lay the main hoop back a bit more.

Reminds me of an acquaintance who had TDI Jetta and read about making it run on cooking grease. He collected a bunch of cooking oil and grease from his family and friends over a few weeks, strained it, and poured it into his fuel tank. He called me (because I am a "car guy") and asked me why it wouldn't run. I just laughed for about 5 minutes. He now owns a Honda civic.

On my old race engine we had a Motec M48 EMS and engine timing was set for each cylinder. I can't quantify any power gains to that specific tune, it was just part of the attention to detail that Sunbelt put into the build. 100 detail changes that make less then 1 horsepower each can add up to a 50 horsepower gain.

No. Conditions are NEVER ideal. What is true on an Internet message board fails when you move into the real world.

Its not just the AFR or engine tune... Inaudible detonation in number 5 (due to a localized hot spot around the exhaust valve seat) on my NA 13.6 to 1 compression ratio engine created enough vibration to drop the seat out of the head on a 3 to 4 upshift. Found most of the seat in the intake manifold. Six new pistons and a lot of welding and machining on the chamber in number five got the engine running again. Cooling system changes as mentioned in other threads solved that problem.

The difference between a late 240Z and an early 280Z chassis is about 100 lbs. The difference between an early 240Z and a late 280Z chassis is about 300 lbs. That's bare chassis weight.