johnc

For autocross you don't need a roll cage, as Keith says. Vic Sias's car ran with only strut tower braces and he won BSP against the C4 Corvettes. If you're planning on doing autocross and open track (time trial) events then I suggest a welded in roll bar with the rear braces attached to the top of the strut towers. This will give you some rollover protection. And spend a lot of money on an FIA approved race seat, harness, and proper mounting of both.

Maxima's Grandpa (810) 2.4L FI L6.

It'll take you a couple years to get the thing running and it will cost a ton of money.

Tokicos probably aren't the ticket if your spring rates are over 225 lb. in. but they are reasonably priced, I have sucessfully autocrossed on them at higher spring rates on a fairly flat surface, and they are great for a street car with spring rates at 200 or below. If you're running rates from 200 to 325 (which I personally feel are too stiff for the street) I recommend the Koni 8610s which have a single rebound adjustment and a set compression rate of 187 lbs @ 13 inches per second. At a spring rate of 250 lb. in. you're right in the middle of the rebound adjustment range.

You can see measurable drag reductions at 70 mph. The old Car and Driver test of aero aids on 1973 240 showed that a vertical air dam in front that lets air spill off the sides and keeps it from going under the front was the most effective at drag reduction. In addition, a 7" tall rear spoiler set to a 30 degree angle gave the best combination of drag reduction and downforce. The combination of both improved fuel mileage 1.3 mpg at 70 mph. And we all thought you were just waving to the crowd as you went through the traps...

Ive changed my tune since talking with the Tokico techs. From about 225 lb. in. you're at 4 on the adjuster to get enough rebound control for those springs. At 250 you're at 5 and at 275 and above you need more rebound control then the shock provides. But, the bigger problem is that the Tokico adjuster also increases compresion damping, which you don't want if you're trying to control the spring. On settings 4 and above there is too much compression damping for a 2,400 lb car. The car tends to skip over bumps and hunt under braking. Now, if you're on a flat, smooth surface, then too much compression damping isn't as much of a problem.

They're fine for a street car and I would run a set on a daily driver. For a race car they are not predictable so adjusting a car for a specific track gets frustrating.

Count me in again.

I'll let you know tomorrow and there's zero chance of him doing any corner weighting unless there's hundreds of dollars involved.

For the rear mount anti-roll bar, if you use the stock Suspension Techniques mounts (which are right up against the transverse link mount brace) the arc that the arm goes through as the control arm moves up pushes the anti-roll bar links forward to the point that the links can't pivot anymore. This stops that anti-roll bar arm in its arc and increases force on that (and the opposite arm) at a non-linear rate. This binding only occurs on a lowered early Zs and only occurs near the limits of rear bump travel. At the traction limit in a corner, a sudden small bump will induce the bind and cause the tail to step out. Once the tail steps out, the bind is elimiated and the rear starts working again. If you're lucky, you just end up doing small steering corrections through the corner and blame it on bumpsteer. If you're not lucky, you end up plowing the back 40. By spacing the ST mounts rearward by about 1" it moves the arms back about 3/4" where they meet the links and frees up the for/aft movment of the links. I've heard the same is true for the front mount rear anti-roll bar but I've never owned a Z with the front mounts so I've never moved the suspension through its range of motion to see what happens.

The front mount anti-roll bar is the stock location on the rear of the late 240, 260, and 280Z. It is not a very effective design. The rear mount anti-roll bar is more effective and allows a reduction in diamater to achieve the same rate. Both the front and rear mounts will bind unless you space the center mounts away from the mounting surface.

Check the oil level with the dipstick. Does it show 1 quart over? If so, drain out about a quart and see if the problem continues. If it does, then replace the oil pressure sender.

Absolutely! Same as the crazy Russians that race Trabaunts on 3 mile road courses, the looney French that race Citroen 2CVs in the dirt, and the myriads of SCCA ITC racer cars that run 17s or 18s in the 1/4 mile. Performance numbers do not define a race car, that's why there are thousands of different classes in hundereds of different sanctioning bodies. Back when I bracket raced a 1966 GTO there was a guy that trailered a bone stock bicentennial Pinto to OCIR. The car ran 20.5 all the time, every run and he usually went home with a few hundred dollars. That car WAS a race car.

From a handling perspective, don't use springs to adjust ride height. Springs are selected to control mass, load transfer, and load transfer rate.

Yes. Expect to spend a great deal of time and money.

Its not the springs. Shorten your struts, install a coil over setup, and install camber plates.

Not to take business away from Sunbelt or Rebello, but if you're shooting for 300 at the wheels on a turbo engine you don't need a lot of headwork. Some port cleanup, port matching of the intake and exhaust manifolds, multi-angle valve job, and a .490 to .500 lift, medium duration cam should get you there. Your time and money would probably be better spent on an engine management system, turbo, intercooler, and plumbing.

I was thinking about running on the Democratic ticket, but they ran out of entry forms last year. Maybe in 2008 when I can go up against Hillary.

Real simple: If you put a helmet on EVERY TIME you drive it, its a race car. All the rest is just BS.

I was thinking about the stock manifolds. You should be fine.

Yeah, that's the pan. I guess the owner of the engine that went boom replaced the pipe plug with a bolt as Jon suggested. Doh!

You have to be careful not to add much of an airflow restriction. The more restriction the more inaccurate the reading because the unrestricted carb will compensate through the balance tube between the intake manifolds. That's why its so hard to tune SUs above idle using a Unisyn.

IRS tends to equalize traction between the rear wheels. With a live axle the driveline torque tends to unload one wheel which causes it to break loose first. Punch it in a corner and see what happens...

Is this the cast aluminum oil pan with the drain plug poking out from the bottom of the pan? If so I know of at least one race L6 that went BOOM! after that drain plug was scraped off on a FIA curb at T-Hill.

I'll have it come hell, highwater, or violent illness. If anything, I can talk about Z handling or talk to you guys about welding. I did a welding talk to a POC group a while ago and they were pretty happy with it.