johnc

Ride harshness comes down to these things: 1. Tire pressures. 2. Tire sidewall height. 3. Tire sidewall construction. 4. Suspension bump travel. 5. Bump stops. 6. Shock compression damping. 7. Friction in the suspension. 8. Suspension bushing material. What are the answers to the questions above on your car?

The Nissan L6 crank is pretty strong. 650 hp in turbo setups is close to the upper limit on power. There are some harmonic issues in the 7,000 to 8,000 rpm range but a good balancer (ATI makes a couple) and forged pistons with lighter, forged rods helps. Compression ratios are good on fuel to about 14 to 1 with the two valve head. You can go higher but not many people do because of hot spots in the combustion chamber. There is no "best" head (remember, on HybridZ there is no best). The P90 has a good combustion chamber design to start from although you'll either need to shave the head .080 or have custom domed piston made to get to your planned compression ratio. If you're going with domes pistons then its probably easier to go with the open chamber N42 head and build the quench in the piston dome. Look at the cooling system mods on this site too. You'll need to do a few things to keep cylinders 5 and 6 from detonating. Also, you'll need to o-ring the block and run a copper head gasket at that compression ratio.

The are two different pedal boxes. One with a 80mm horizontal bolt spacing and one with a 100mm horizontal bolt spacing. You need to get the correct pedal box for your firewall. You can't just redrill, the holes are too close and you'll end up with a flexy firewall and mushy brake pedal.

There's no need to defend yourself when someone calls you names.

For a fast track car, its not the parts, its how the parts are tuned.

That's normal. Could be the tightness of the seals, the style of diff, whether there's any oil in the diff, etc.

Check the wiring grounds for the blower motor.

Its a metal lock nut. Its supposed to get tight as it fully engages the threads. You tighten it down all the way like a normal nut.

The weight of the car should push that bearing up into the correct position in the insulator along with the upper spring perch. I think you drilled the hole a little too big, normally I drill the hole to rest on the first step for the BZ3099s.

Yoke stiffness? Sounds like a male porn star. Are you talking about how much torque it takes to turn the input flange on the diff?

My car had 275/45-16 Hoosiers on 10" rims and Rylan's car had 11" wide racing slicks in back, 9 or 10" wide in front. And I had probably twice as much money into my car then Rylan has in his S2K. My engine, EMS, clutch, manifolds, exhaust, etc. cost more then his car did new. Add in a Quaife sequential trans and Penske 8760 triples and you could have got a couple S2ks for what was in my 240Z. The comparison between Rylan's car and mine is the closest real world track comparison I know of. At the time of OTC 2003 Rylan's car was fully developed. It was my car's first race outing after one day of track testing an tuning. After another year of tuning on my car and we dropped more the two seconds off those WSIR lap times. The rematch for 2004 never came about because Rylan blew his engine the day before the event in testing. Here's a pic of my co-driver Bryan making Rylan's junk engine his bitch:

I beg to differ. For the 2003 Open Track Challenge my Rusty Old Datsun (2,150 lbs, 320 hp, Penske shocks, Hoosier R4s) went up against Rylan Hazelton's S2K (275hp, 2,250 lbs, JRZ shocks, Hoosier Slicks) and it was close. We battled on seven race tracks over seven days and Bryan and I barely beat Rylan and Aaron. The handling advantage the S2K has over the S30 is big. http://pulpracing.com/otc8_2003.htm

2,000F epoxy is PLENTY high temp enough! I was thinking more like 500F and even though JB Weld says it can go that high, it softens over time.

Put the hub face down in a big vice with aluminum jaws. Clamp the wheel studs, tighten away. Or put the hub face down in a wheel/tire on the ground. Stand on the tire and tighten away.

Yes. Stop immediately in a controlled manner at the side of the track. Ideally you stop in such a way that you can see and be seen by a corner station. Each track has its event supp regs that say you should stop on the inside or the outside of the track.

OK racers, identify all the errors committed by the driver(s). This was last weekend at a Buttonwillow VARA race. EDIT: This was a VARA race and look at the corner worker.

You might want to think about a Road Atlanta rear gear for your car. Find another R200 with a 15% higher (lower numerically) gear so you don't use 5th at all. Or go the other direction and fit a 20% lower (higher numerically) gear so you are farther up the rpm band when you up shift to 5th. I use the rear gear to tune the shifting for the track I'm at. I used to have 4:11, 4:36, and a 4:64 built up R180s in the trailer. Its expensive but I got all that money back when I sold them after parting the race car out.

If you get a tight enough fit on the patch panel you can use a high temp epoxy (not JB weld) to put the patch in place. Once its dry, sand and paint.

Because, in road racing the S30, 1st and 5th gears are rarely used so the focus is on the 2nd, 3rd, and 4th gaps. And the real focus is on the gap between 2nd and 3rd. The Holy Grail for people road racing the 240Z is the Nissan Comp Option 3 ultra close ratio direct drive box: 2.192, 1.601, 1.470, 1.138, 1.000.

-6 is fine for a diff cooler with the pump flow you list. One important thing to keep in mind is the diff oil level with the pump not running. You will have to mount the cooler, pump and lines lower then the stock oil fill level in the diff. Otherwise, with the pump off, the oil fill level will be too high.

Cut out the dent, form a piece of aluminum to fit the cut and and shape it correctly to match the rest of the cover, weld it in place, grand, sand, and smooth it down.

IMHO, its worth it in conjunction with other engine efficiency mods - its one of the little things that really adds up in combination with a bunch of other little things. If its the only thing you do to improve engine performance, its not worth it.

Flow rate is also at some psi number. You can't have flow at 0 psi or there would be nothing to impart flow. There has to be pressure (or pressure differential) to get a fluid to flow - unless you're talking about thermodynamics.

Longer springs go in front.

Look for an acid based aluminum brightener (Super S, Power Purple, JASCO, etc.) Test it on a small part first to make sure it won't damage the metal.