johnc

What is the size of the compressor outlet on your turbo? If its 2", I don't think you are going to gain anything by going with larger intercooler piping. You'll just be creating a large plenum that has to be pressurized and re-pressurized when the BOV hits.

Combining the upper spring perch with the monoball reduces side loads on the shock shaft and frees up the suspension. But, monoballs are not designed to handle large side loads so camber plate manufacturers typically put the spring loads from the upper spring perch directly into the camber plate. This does impart side loads on the shock shaft from the bow that is put in the spring as the strut assembly moves up. Its a compromise that's done to keep from having to frequently replace the monoballs.

.030 sheet metal is about 22 gauge and is thinner then what you find on a 240Z. You should not see any drop through on the backside. You should see discoloration.

More power to you, I hope you get those results! With around 200 hp most of the ITS guys I know rebuilt their clutch pack LSDs at least every 2 years and the couple GT2 guys I knew who were running coolers and heat exchangers rebuilt their diffs on about the same schedule.

Extreme examples of high and low yaw inertia cars are good as examples only. In the real world of racing too much or too little of anything is not good. In the world of autox 240Zs have done very well and still do well here in Southern California. I'm building a Solo2 SM2 240Z for a customer right now.

A better term is Yaw Inertia. Yaw is the spin of the car around an imaginary pivot - like a top. In an airplane yaw is when the plane is moving at an angle to the actual direction of flight. Yaw is easily seen as a plane is landing in a crosswind, the plane is pointing into the wind a little bit and appears to be flying sideways. Yaw Inertia is the resistance to yaw. Yaw Inertia is affected by tires, track, wheelbase, alignment, aerodynamics, weight, and weight distribution. For this discussion we are just focusing on the relationship between weight distribution and yaw inertia. Weight distribution affects the amount of forced needed to induce yaw and the force needed to contorl or stop yaw. A car with a 50/50 weight balance where all of the weight is inside the wheelbase has very little yaw inertia. Like a top where most of the weight is centralized, it spins easily and quickly. A car with a 50/50 weight balance where most of the weight is hanging outside the wheelbase has a lot of yaw inertia. Like a gyroscope, it takes some effort to get it spinning and spins slower then the top given the same amount of initial force.

Dang it! Keith corrected my example above on a related post over at ZCAR.COM. I had the numbers wrong. That's why I dislike progressive or dual coil springs - my brain can't handle them.

I just had a customer's 240Z media blasted with walnut shells. Came out very clean and the car had a number of paint layers, bondo, and rusty rockers. I sprayed the whole car with a light mist of WD40 when I got it back to keep it from rusting. The WD40 cleans off easily with Acetone or BrakeKleen for all the welding I need to do on the car. Before I sprayed the car with WD40 I called a car painter friend. He specifically told me to use WD40 and begged me not to spray it with any primer. He says he gets cars in that have been sprayed poorly with junk primer and he has to strip the car. Its much easier for him to have his laborers wipe the car down with PrepSol to get the WD40 off.

Mark Ortiz's latest newletter expands on this topic.

Also, if you have the dimensions of or would like to build another front diff aluminum crossmember I would be intersted in one almost immediately.

One welding tip (although with the thickess of the materials used this tip is not really needed): Weld all the way around two parts being joined. In your picture above of the gussets that are added between the clevis and the center plate where the diff mounts, the welds are not carried all the way around. The gaps at the ends of the gussets are places where cracks can start. Again, in this instance its not relaly an issue. If this part was made of aluminum then those unwelded ends would start cracking.

A story about effective misdirection... A 240Z ITS competitor (let's call him Bill) had an illegal compression ratio in his 2.4L. To keep that from being discovered he stamped "NISMO" on his absolutely stock camshaft, because removing the valve cover is typically the first thing that's done in tech when someone questions the legality of a L6. 15 seconds after the valve cover came off a competitor went ballistic and claimed an illegal cam. Bond was posted, cam was pulled and checked, cam was declared legal, Bill kept his divisional championship, and pocketed an extra $200.

If you're talking about moving the stock window frame to the body, you'll have lots of problems opening the doors with the windows rolled up.

That header should work fine, although from what I've been told it would do better with more duration in the cam. If you're going with a 3" single exhaust, the "Y" pipe is important. Try to run a true merge to a 2 5/8" outlet that has a long taper (14 degree) transition to a 3" outlet. Something like this: http://www.burnsstainless.com/MergeCollectors/mergecollectors.html

That's funny, someone used "Carburator" and "21st Century" in the same paragraph.

I just want to clarify one thing, Sunbelt never built an L6 engine that made 370hp (at least when I talked with Jim about it back in 2000). If I remember right, his biggest horsepower claim was around 350 for an L24 that spun to 8,500 rpm. His mention of 370 hp was based on being able to spin a L6engine to 9,000 rpm or more, but that engine would be a qualifying engine that wouldn't last very long.

All autodarkening helmets are designed to fail to a shade 5 or better so ther'es no harm from intermittent exposure. I often use my auto helmet turned off to do plasma cutting.

You can buy separate soft horsehide sweat bands for the head strap on your welding helmet. Highly recommended and with a little scissor work the sweat bands can fit the side and even the back straps. A welder friend swears by Optrel sweatbands, which I haven't tried yet. http://www.weldingsupply.com The site looks like crap but they have good prices and ship quickly.

The Nissan part numbers for the comp trannies are: 32010-N3130 - Close Ratio O/D Transmission. 32010-N3030 - Wide Ratio O/D Transmission. 32010-N3220 - Option 1 Race Transmission 32010-N3221 - Option 2 Race Transmission 32010-N3222 - Option 3 Race Transmission 32010-N3201 - Rally Transmission 99996-C3040 - Special Trans/Speedo Drive Plug Gearing is as follows: N3130 1st - 2.906 2nd - 1.902 3rd - 1.308 4th - 1 5th - .864 R - 3.382 N3030 1st - 3.321 2nd - 2.077 3rd - 1.308 4th - 1 5th - .864 R - 3.382 N3220 1st - 2.818 2nd - 1.973 3rd - 1.470 4th - 1.192 5th - 1 R - 3.382 N3221 1st - 2.348 2nd - 1.601 3rd - 1.296 4th - 1.138 5th - 1 R - 3.382 N3222 1st - 2.192 2nd - 1.601 3rd - 1.470 4th - 1.138 5th - 1 R - 3.382 N3201 1st - 3.321 2nd - 2.270 3rd - 1.601 4th - 1.240 5th - 1 R - 3.382

I've also heard rumors that the EPA is making the airborne Hexavalent Chrome standards 10 times more stringent next year. The cost of the equipment needed to meet those standards is prohibitive for small operations.

A little welding fire story... I've got a Honda S2000 in the shop and the customer wants the front upper LCA mounts welded up (on the early S2Ks the mounts pull out of the body under heavy track use). He had some connections at American Honda and two engineers and the engineering manager were there to see what I did to fix/prevent the problem. It takes a little work to remove the undercoating and paint to get an nice surface to weld. I have a few Acetone soaked rags on the floor near where I was going to weld, so I moved them back a few feet. Well, as you've guessed, they rags caught fire. It was no big deal because I usually keep a wet towel at hand whenever I MIG weld, and the rags were just sitting in the middle of an open concrete floor. As I reached for the wet towel Mr. Engineering Manager decides he is going to play fireman, and stomps on the Acetone soaked burning rags with his size 11 wingtips. Now I've got a pile of buring rags and a buring wintip attached to a dumbfounded man. I throw the towel over his shoe and the fire goes out. He starts to make a comment about fire safety in my shop and I stop him and say, "Sir, I am required by law to ask you to turn in you're Junior Fireman badge." He shuts up and goes in the bathroom to wipe off his warm wingtip.

Forget exhuast flow and horsepower, think how much weight you'll save by going with a single pipe and muffler.

That's a radioactive mercury based coating used on nuclear pressure vessels. You shouldn't breath the dust or touch it with your bare hands.

DOM and 4130 tubing typically have a gray/green surface coating called "mill scale." It needs to be cleaned off before welding. 220 grit sandpaper quickly takes it off.

Some semantics: Fuel Cell - A rubber or Kevlar bladder that the fuel is actually contained in. Typically has internal foam baffling to reduce vapor and keep the fuel from sloshing around. Road racing fuel cells are rated by the FIA. Drag racing and street fuel cells are either not rated or SFI rated. Can - The container the fuel cell is surrounded by. Fuel cells must be installed in a container of some kind. Sometimes that's a spare tire well, an aluminum or sheet steel box, or inside of an existing steel steel tank. The fuel cell is the most important part. It is deisgned to resist impacts and punctures and keep fuel from leaking out. FYI... a plastic fuel tank with fittings on it is not a fuel cell.