johnc

Us Yanks can get a bit testy at times....

Use the search funtion on this site as a start.

There's a big difference between driving instruction and track testing a car for setup purposes. If you're asking an instructor to drive your car to feel its "setup" and/or offer you setup advice, then you can expect it to be driven at its absolute limit. There's a good chance it will be damaged to some degree: flat spotted tires, possible engine overrev, worn clutch, off-track damage, etc. That comes with the territory when diving a car at and beyond its limits (FYI... you have to drive it beyond its limits to find them out). When Erik Messley was setting up the brakes and suspension on my 240Z at Buttonwillow we went through two sets of tires, a set of brake pads, and I had to change all the fluids after. That was in two hard hours of driving.

Some track schools do just that, although the make of the car isn't really important (competition licenses are for a sanctioning body, not a vehicle make). Others don't require competition licenses to be an instructor and in some cases don't even check out the purported resume of instructors. Like anything else in the world, you have good driving schools and bad driving schools. Your example is a situation where an instructor has misjudged his student's abilities. The instructor needs to bring the pace down so the student is less afraid (but not actually comfortable) and can pay attention. If the instructor feels the student is still over his head at a pace that's too slow to be safe on the track, time to pull in, give the student his money back, and ask them to leave. I've done that with a student (a wife) who was talked into doing a school by her husband. I also lectured the husband for about 10 minutes privately after he started berating his wife for not driving fast enough. But, sometimes students don't listen. I've had to take the wheel in a turn when a student "froze" and started to drive straight off the track. I've also made a student stop the car off the track and got out and walked back to the pits because the student wanted to play Luke Duke in his new Z06 Corvette. He was told to go home and he didn't get his money back. Weeks later his car was on http://www.wreckedexotics.com.

When I'm acting as an instructor I will rarely drive a student's car; I often refuse even when they ask. Mostly for the issues we're discussing here but, also, I don't think a student learns as well unless they are behind the wheel. If a student doesn't "get" a specific point I'm trying to make, I might then drive the car just to show the student what I mean, but I always stick to that point and I don't try to run a "fast lap" to impress. I want the student to leave the event having learned something, gained confidence in their abilities and their car, and had a lot of fun. I want them to leave thinking they can kick my ass on the track. Hopefully they come back and start competing. Now, let's turn this discussion around. What if the student went off the track after ingnoring the instructor's advice, wrecked, and injured the instructor. Should the student pay for the instructor's medical bills even if the insurance bails?

You have a thrid option that I would recommend: 3. Replace the worn out stock parts with new. If the engine is basically stock you're not going to improve performance with either carbs or an aftermarket EMS.

Not many driving instructors get paid at these kind of open track schools. Most do it for track and seat time. Also, one person's "balls out" is another person's "easy lap." I've scared the crap out of students when I was driving an "easy lap" in their car. That was a mistake on my part by not realizing where my student's threshold was.

As an instructor at a number of driving schools I can give you my OPINION about what should be done, but that's not worth much. Eventually it will come down to a negotiation between the car owner and the instructor. FWIW: The instructor broke the car through his error in operation. He should pay to fix the car. The 4th to 2nd downshift blow up is a common and known thing in the E36 chassis M3s and I know of four cars that have had this exact thing happen. There's no track that I've driven and no reason that I know of that requires a fast 4th to 5th shift. That being said, the car owner should also pay for part of the damage because its part of the risk the risk he accepted when venturing on the track and asking the instructor to drive the car. The car owner also should realize that the instructor can probably just walk away and leave the owner with ALL of the costs. Even if it goes to small claims court the chances of getting a sympathic judge will probably be small, "You asked him to drive your car on a racetrack and it broke? You were aware of the risks involved correct? How is the instructor responsible?" My recommendation: talk with the instructor in a calm and polite manner and work out something with him. Yelling, screaming, and threatening lawsuits only hurt the discussion. Think lawsuit only after you've exhausted all options. And... if the instructor has no money, you can't really squeeze blood out of a turnip.

The dents and bends in the frame rails and the dents in the floor pan are common. They come from floor jacks that are used to raise one whole side of the car. Most often seen on racing Zs. My 1970 has lots of dents/bends in that area and I occaisionally take a big rubber hammer and pound the floor pans back flat. Its a cosmetic issue, not a structural one.

The max power air fuel ratio (AFR) will be the same for each cylinder at every point in the rpm band. The issue is not what the AFR should be. The real issue is how to get that ideal AFR in each cylinder at each point in the rpm band. If you are able to measure the AFR for each cylinder and your engine management system allows you to tailor fuel delivery for each cylinder then its just a matter of measuring and adjusting. But, only a few high end EMS systems allow that much tunability. Most of the time you're measuring AFR for a group (or all) or cylinders and adjusting the EMS to that "summary" AFR number making sure the leanest cylinder is running at something like 13 to 1. Other cylinders may be running richer and thus producing less power then the theoretical ideal. Again, its basically a matter of measuring, adjusting, measuring, adjusting, etc. until you hit a "summary" AFR that produces the most power while still keeping the leanest cylinder from detonating. And to (finally) answer your question, yes the "summary" AFR number will vary with RPM because of variances in each cylinder's actual AFR number throughout the rpm range.

Most have some type of coarse adjustment but it doesn't tell you what the torque number is. Try and find one that goes to only 250 ft. lbs. and then adjust it to the halfway point. When tighteneing the nut down let the gun hammer only twice and I'll bet you'll be pretty close to the torque spec.

Us an impact gun. Vice grips on the shaft can and often do damage the shaft. Vice grips are hardened also.

The E30 head wasn't delivered to the US on a Nissan product if my memory is correct (which is often not) so most of us don't have any information about it. Maybe one of the folks from Europe? The E88 head works on an L28 block but the compression can be too high for US fuel. If your E30 looks like an even smaller combustion chamber then the E88 then your might have some problems with fuel in your part of the world. Try ccing the combustion chambers of each head to find out if the E30 actually has smaller chambers.

Its just different styles of negotiating guys. Don't take it personal. If you've ever negotiated with someone from outside the US and northern Europe you can expect this type of lowballing. Its not a sign of disrespect - in fact, its considered disrespectful to the seller if the buyer walks in and pays full price WITHOUT negotiating.

The 240/260/280Z is not designed for hub centric rims. And let's not start the discussion about whether hub centric is "better" then lug centric. Suffice to say that my Z spends all its time on the track at high speeds and lug centric wheels work great.

Why would anyone need that?

I don't know if that 16x number is correct. I suspect its wrong but I don't have the calculations to back up that opinion. You also have to consider the amount of time the fluid is in contact with the fin area. Heat transfer takes time and the more time the coolant is in contact with the fins the more heat can be transferred. In single pass radiators the fluid only passes theough the fin area once. In double pass the fuild travels through the fin area twice. Now, that doesn't mean it cools twice as fast but it does increase heat transfer by some substantial number. On my L6 I'm runnig the stock water pump and have no problems with coolant flow, etc. We've even put a restrictor in the system to slow down flow through the radiator. I do need to increase system pressure to eliminate some local boiling in the parts of the head, but that's system pessure, not flow pressure.

I bought RacerX's (Ernie) 1977 810 sdan a few months ago. He had gone through the interior and replaced all the worn peices and its got an uncracked dash. No pan, rocker, or structural rust but the bottoms of the doors have bubbles. Lots of other things were replaced (upgraded) on it and I drive it all the time.

I know of a 2000 Volkswagon Golf TDI (direct injection diesel) 4 cylinder running aorund SoCal that turns low 12s. His last chassis dyno run saw 353 ft. lbs. of torque and 207 hp. He keeps skinny tires (195s) on the front because he got tired of blowing up transmissions. BTW... its blue and it doesn't blow any smoke.

Well... I'm not a fluid dynamics engineer just a monkey-see, monkey-do engineer. I agree that a double pass radiator is not needed for a street car. But, when I go to SCCA, ALMS, NASCAR, USTCC, and other sedan racing series events I see 90% of the vehicles running double pass radiators. The advantage is that you can run a smaller, lighter radiator and get the same cooling capacity (maintain correct engine temperatures). I currently run a C&R/Visteon double pass aluminum radiator with a built in Niagra heat exchanger. It keeps coolant temps between 200 and 210 degrees even when racing at Willow Springs in July. It also weighs 15.45 lbs empty including heat exchanger, radiator, and 4 -10 AN fittings, and is smaller then a stock 240Z radiator.

The weak point in the two spider gear R180 is the two spider gears. I haven't ever seen an R180 fail in the ring and pinion gear (excluding lube failures). If both wheels are hooked up and or burning out then the spider gears are not doing much work. When you do the big one wheel burnout the spider gears are working hard and bearing all the torque going through the unit. That's not a big deal until you start increasing the torque (via engine mods) going through the unit. Then, blammo! The four spider gear R180 is considerably stronger but its hard to find (I have yet to see one outside of Nissan Motorsports). The R190 normally has four spider gears. For the two spider R180, swapping in a Quaife or the Nissan Comp "competition" LSD eliminates the spider gear issue. Also, welding up the two spider gear R180 eliminates the problem discussed here.

I've got a short mpeg clip of #37 and its just freakin' amazing what those two guys did on the last couple laps. I watch it again and again.

I talked last Friday with Devin at Unitrax about gear oil for my R180 with a Quaife. I had been running Redline Shockproof but wasn't happy with the heat control. Devin recommended Lubrication Engineers' 9921 75W-90 for any application that might see temps over 300F. Its what they fill with for Quaife installations in racing Corvettes and Vipers. For lower heat applications (any street setup) he suggested 703 80W-90. Quaife and Torsen units generate a lot of heat, usually more then you'll see from a clutch pack LSD. They do require more torque to move then a clutch pack LSD and that heat load, along with the additional internal gearing and resultant shear loads, generates a lot of heat.

The fuel coming out of the end of a modern fuel injector is very well atomized. Much more so then fuel coming out of a carb. There may be a concern about creating a homogenius mixture but proper combustion chamber design and positioning of the injector will eliminate that concern. If, when you're discussing MPFI running out of breath (actually, not delivering enough fuel) at high rpms, you're refering to OEM systems, then the reason is: the injectors run out of duty cycle time (meaning the pulse injector is full on all the time). OEMs specifiy injectors that are specifically sized for the application. They will only flow so much fuel and the OEMs probably specifiy a 10% cushing to handle additional false air as the vehicle ages. The injector duty cycle issue also applies to OEM SPFI systems. Those two or four injectors at the top of the manifold can, again, only flow so much fuel. Going to a larger injector that can deliver more pounds of fuel might allow an OEM MPFI (or SPFI) system to handle the rpms you're looking for IF you also reprogram the ECU, ensure the fuel delivery system can handle the additional flow, and do some other tuning. But, I think it might be cheaper in the long run to start with an aftermarket MPFI (or SPFI) system then to try and modify an OEM based system.

Sounds like "marketing technology" spewed forth by companies selling carb replacement fuel injectors. None of the above is true for reasons listed by Afshin and many others. I don't know where to start to direct you to the correct information about the advantages of multi-point fuel injection over single point. My mind has been boggled. There isn't one place (except maybe cost) where single point fuel injection has an advantage (is better) then multi-point. I guess the only thing I can say now is that I know of no automotible manufacturer anywhere (except maybe Trabant or Yugo) that is currently running a single point fuel injection system on their 2003 model vehicles. Regading what racers run - check the rule book before deciding the reasons why things are done the way they are.