Leon

Yep. Dynojets are plain, inertial-drum dynos, which measure how quickly your wheels can spin up a drum of known weight. Power is calculated as Torque X Speed. Torque is calculated using T=Ia, I being rotational inertia of the drum and a being acceleration of the drum. This is a less accurate way of measuring actual power, since you're inferring power from how quickly you accelerate the drum. This also means that changing things like flywheels, brake rotors, tires, driveshafts, etc. will show a change in hp on a Dynojet, even though your engine isn't making any more power. Conversely, something like a Mustang dyno is a "brake" dynamometer, which uses a fluid or electromagnetism to put a force on the roller and against the wheels. These types of dynos measure (not calculate) actual torque delivered to the drum by way of a lever arm connected to the brake and a load cell that measures force at the end of the lever arm. This force is used to calculate torque, which is then used to calculate power, using Power = Torque X RPM. Therefore, a brake dyno (e.g. Mustang) provides a much more accurate depiction of actual power than a purely inertial dyno (e.g. Dynojet). My apologies for the tangent!

Brake bias is not a "set and forget" kind of deal, this is why cockpit-adjustable proportioning valves exist. As previously alluded to, weight transfer changes depending on the level of grip. Production car brakes will be set to best grip scenario, i.e. in the case where you have the highest amount of weight transfer to the front. Thus, the brakes are tuned to be heavily biased towards the front. Tuning the brakes to best-grip is safest, since the fronts will always lock first, no matter what surface you're on. If you tune to wet conditions, you will have too much rear bias for when it's dry. This causes an unstable condition since you'll be locking the rears before the fronts and going for a ride on the carousel. Therefore, you must tune the brakes with the same grip conditions as you plan to experience on the track. Ideally, you'd be tuning at the track, but as long as you're using the same tires and similar ambient conditions, you should be close. If you want to set your brakes for the wet, you'll have to go through the same procedure, increasing rear bias until the fronts lock just before the rears. This gives you two distinct rear bias settings, "dry" and "wet".

Exactly. Runner geometry should be based on having as little pressure drop as possible, while having them tuned to your specified rpm range, i.e. "resonance tuning". Tuned rpm depends on intake length, diameter, air temperature, and valve timing. Generally speaking, a longer and/or narrower intake tract will be tuned at lower rpm, and a shorter and/or wider runner will be tuned at high rpm. Holding runner geometry constant, increasing cam duration will shift your tuned rpm range higher and decreasing duration will shift your tuned rpm lower. Temperature plays a more minor role. Keep in mind that frictional losses increase with the square of velocity, which is inversely proportional to the square of the diameter! With that said, these properties would push me to use as wide of a runner as possible, while matching it up to the head port, and varying intake length to get my tuned rpm. Air horns or a taper cast into the intake at the proper location will widen your tuned rpm range and a radiused entrance will decrease entrance losses. That should give you a start!

You can always cancel the transaction before they ship!

I'm not discounting nor debating the merits of your project. Try to internalize what I've said (wrote), instead of picking one aspect and debating it. We're talking about building any sort of car. Who said "aero" or non-"aero"? Maybe my L28 Roadster is going to have a splitter, and a huge wing. That's not the point... I'll repeat: With an understanding of the dynamics involved, you can make almost anything "work" right.

Seconded. I bought a cheap ebay Champion radiator and it's been cooling great. It's been on the Z for about a year and a half.

Like NewZed said, the difference between a 3.54 and 3.9 is small. I doubt fuel mileage would change much, if at all, and your top speed is limited by aerodynamics, not gearing. You'll be fine with either, but I'd probably opt for a 3.54 if you have a torquey turbo. I'd save the 3.9 for something a bit more tightly wound. Here is a great site to compare gearing, numbers and a nice chart: http://webspace.webring.com/people/cz/z_design_studio/

I wouldn't mind at all. Hell, I'll help install the shocks right there in my driveway if that were the case!

Could you elaborate on whether the aforementioned required octane rating is RON, MON or API? An N42/N42 will run on 87 octane with ease. I run 89 in my L24/E88 and the E88 has machine shop scribes, so it's possibly slightly shaved (don't remember if it has cam tower shims, but comp is likely a bit over 9:1).

I don't drink, so you'll be sipping on a beer whilst I pop open a fresh, cool bottle of Martinelli's apple cider. There is something you need to understand, however. Like I said earlier, one thing like weight distribution (that LONGER engine under the hood) is not going to kill a design, nor is it going to make it a winner. Staying true to the point, just because you put in a V6 into the Roadster absolutely does not automatically dictate that you've improved any of those attributes you mentioned. The answer to this question is simple: Because I (or you, or he, or anyone) want to. There is no "optimized purpose" but rather there is a design intent and the car is modified in order to fit within your specifications. I'll repeat, 50-50 is not "perfect" weight distribution, because there is no such thing! You may still be skeptical, but Formula 1 cars and many other race-cars do not have 50-50 weight distribution. They are rear-biased, some more than others. Are you going to walk up to an F1 engineer and tell them that their weight distribution is not perfect? The chassis can be tuned to your liking, and there is a compromise to every decision. A well set-up 70/30 car can outhandle a poorly set 50-50 car. It's all in the chassis tuning. Rotational inertia and traction to the rear wheels are the extra pieces to this topic, the merits of which I brought up in a previous post. You want an autoX car to be able to dance around cones because of low inertia, but do you want a Bonneville LSR car getting squirrely or spinning at 200mph because of low rotational inertia? Like I said, it all depends on your design intent. What's perfect for one is crap to another!

I have a bingo!

I have a used set of KYB GR-2s that I pulled when I did a suspension rebuild. All are in good working order, and likely not a lot of miles on them (I removed them shortly after I got the car). They're boxed up and ready to be shipped, send a PM if you're interested!

FYI, the dyno numbers you're getting are likely "corrected" so temperature differences are already accounted for. Any overlaid dyno sheets from the Mustang dyno? Glad to see the hard work led to some gains.

Only one way to find out... If the head is not shaved and you have spark and fuel tuned right, you can probably get away with regular with a stock E31/L24. Otherwise, you may need to bump to a higher octane. Dynos help determine this. Oh, how I wish I had pressure transducers inside each combustion chamber and a data-logging software for it... one can dream, right!

You guys realize that this is going to drive up the prices of 280Zs and ZXs, right?

What I'm saying is that you shouldn't discount an idea, a design, simply because it doesn't have "perfect" 50-50 weight distribution. This is an automotive fallacy, 50-50 isn't necessarily perfect. What's "optimized" for you may not be optimal for someone else and their design intent. Like I said, one single thing (like weight distribution) isn't the bane, nor is is the the sole key of success in vehicle design.

Unless you set it up correctly... People often mistakenly equate weight distribution to the understeer/oversteer propensity of the car. The suspension can be tuned to match the weight distribution, among (many) other things. You can take a 70/30 car and make it have steady state oversteer. Weight distribution/location does affect the rotational inertia of the vehicle. The more centered the mass, the easier it is to change it's velocity. This is good for quickness (anything involving changes of direction) but also has a destabilizing effect (less resistance to turning, i.e. less time to react, harder to correct, more sensitive to inputs, etc.). The other point is that a front heavy, rear-drive car will be at a disadvantage regarding traction on acceleration. There are myriad things that affect vehicle dynamics and you can't chalk up a car's handling to just one of them, e.g. weight distribution. Veering back on topic, looks like the owner has already dropped down to $1250 upon realizing that it's a 1600 and not in the best of shape...

Disclaimer: I'm no MS expert, nor have I even played with it. Sounds like there is some closed-loop feedback coming from the O2 sensor. Turn off O2 feedback and see if that helps.

No problem, be sure to check the sub-forums in the FAQ section!

You mean something like this?

FYI, Here is a follow-up post from CL: FWIW...

Nice! I believe that's a Honda N600.

Let me know if you're ever in the area! PM me and I'll give you my number so you can save it for when the time comes.

I'd take you up on that if I were anywhere near LA! Glad to hear that you've solved the problem. On to the next one...

I've seen them on a few Zs, pretty sure they were made by American Racing.