Leon

Regrind from the stock cam is the way to go, due to the matching wear surfaces.

Another thing to note from that chart, is that the higher your grip conditions the more sensitive brake bias becomes with regard to maximum deceleration.

Not only that, but optimal brake ratio changes depending on grip. You want more rear bias in rain and less in the dry, due to weight transfer effects. I've attached a chart I have from a braking spreadsheet I did back in my vehicle dynamics class (don't look at the discontinuities at the tips ). The model is a generic "street sedan" weighing 3220lb, with a 55/45 weight distribution and 3ft high CG. It shows three conditions: wet, low grip, and high grip. In the wet, optimal brake force distribution is 60/40. If your brake force dist wanders to the left of the vertex, your rears lock up first (too much rear brake force). The opposite is true when going to the right of the vertex. This applies to all 3 braking conditions. For a "set-it and forget-it" setup, you need a bias that never locks the rears first. This means setting your bias to the highest grip condition. The con is that your braking distances will be further increased when using this bias on a lower grip surface. For example, you set bias to 86/14 for the high-grip condition. Then it rains. You now have 70% of optimal maximum deceleration on that surface with your set-and-forget bias. Again, these are numbers using a made-up car and approximate mu values for grip conditions. It's simply an example that illustrates what's going on. Braking Chart.pdf

Wow, interesting ad to say the least...

Great compilation, Takashi!

Nice Mike! Looks like a great LeMons/Chumpcar entry.

I think this is the type of curiosity and thinking that we welcome at HybridZ. Looks good to me, at a glance. I would call those "torques" and not "moments", but that's nitpicking. Luckily, designing brakes isn't as complex as engines or suspensions. To dial in the balance mathematically, you need to now the friction force between the tires and road, vehicle weight, wheelbase, CG height and CG longitudinal placement. With that said, our car is already designed so jumping in and finding optimal balance empirically makes more sense, especially given the lack of info on CG locations and tire data. Brake force needed can then be back-calculated to see how much pedal force is needed, knowing tire, rotor, and piston sizes, and pedal lever ratio. The Brake Handbook by Fred Puhn is cheap and a good read, if you're interested.

Correct, piston area affects braking force, not pad surface area. This is physics 101: F=μN. Brake force depends on the coefficient of friction between the pad and rotor (μ), the amount of force the pad exerts on the rotor (normal force, N), and rotor diameter at which the force is exerted. It's the force that matters. Two small pistons don't necessarily exert more force than one big one, it's the combined area that matters. I don't know the piston areas off the top of my head.

Dyno time!

I'm pretty sure he did, but I didn't check (nor know the differences between the two off-hand).

Nice job!

Yes, they were both maxed out.

HBZ Rules sirbinly, sorry that such a mess has been made of your WTB thread...

FWIW, the 260Z prefix was "RLS30". R means L26, H means L24 or L28, depending on model.

Unless the car is tuned properly for the catalyst (controlling its temperature which is AFR, CR, Timing and cam dependent), the converter will degrade in a matter of months. As for the other question, see above.

Not around here. I bought rust free rollers for <$1k and drivers for ~$3k. Come to CA and buy it here, then ship it back. All you really need to do to make it look like a 240Z to anyone besides knowledgeable Z enthusiasts is change the bumpers. A decent set will run $300-400 plus you'll need some $40 brackets (or make them yourself). BTW, there is no need to have 18 arrows and 53 periods at the end of a sentence.

There's a good chance they're SAE threads, as T-B alludes to.

I sent the P90 cam to Isky for a custom regrind today. I also heeded Steve's advice and took a crank pulley along with a couple of flywheels to the shop for balancing. I'm hoping I get my bottom end stuff back by next Friday, but I'm not sure what the timeline on the cam will be.

I got some Duplicolor engine paint at O'Reilly, Pontiac DE1610. It's about the closest you get to the stock color. I also got some self-etching primer for the block, as recommended by my engine guy. The WD will be removed and I will be cleaning everything obsessively, that's for sure. Thanks Jim!

Both the pulley and flywheel should be balanced all by themselves, as this is an internally balanced engine. The reason I'm not as concerned about the pulley is because it is a smaller-diameter part compared to the flywheel and "should" be balanced as long as it's in good shape. Plus, I may buy a new pulley in the near future. The flywheel is an old 10lb Tilton unit and I'd like to make sure that it's in good shape. Plus, I'd have to figure out which pulley I want to use from my collection!

Engine is back from the shop! Block was bored out .020" and decked .004". It's a bit wet from a generous dose of WD40. The head was shaved and got a 3-angle seat cut. Rods and pistons were balanced, pistons mounted (ITM flat tops), and rod bolts pressed in. Today, I finally took my crank to a shop close to work who will polish it and send it off to be checked for balance. I'm including the flywheel with it to be balanced as well. Figured the crank pulley should be in balance, but I'm thinking of taking it in as well.

Guys, before we delve further into this, I helped mistah mofro work on his car last week... Comp came out OK, but oil is white and milky. It could very well be from condensation but needs to be changed ASAP. Then, I confirmed TDC as best as I could (plugs out, looking with a flashlight into #1 plug hole while Alex turned the engine). We marked the pulley at TDC and then checked timing. Timing at idle is somewhere in the range of 0*-5* retarded with both distributor adjustment screws maxed out. This is why the car has no power and backfires through the carbs (and a nice big one from the tailpipe). We moved the plugs over by one spot but that resulted in so much advance that the car wouldn't start. I think the carbs were then tuned very rich to compensate (also carbs are out of sync but proper timing needs to be established first). I told Alex that he needs to re-orient the oil pump spindle per factory instructions, so hopefully that is done soon. The engine was swapped out of another car that was apparently running well and the only thing that was changed was the distributor. This leads me to think that there are minute differences in adjustment screw locations which in turn doesn't let the ZX unit advance as far as whatever distributor that was in there.

I'm betting it's fuel/carb related. Sounds like the culprit is the emulsion tubes, since it seems to be a common characteristic of DCOEs with F-series tubes to lean out at higher RPM.

Got some 7075-T6 shim stock today and modeled up the shims... I'll be cutting them on a CNC wire EDM for accuracy, plus there will be no burrs for me to clean up. Just perfectly sharp corners.

Longer braking distances (than stock).