Nigel

As mentioned, do NOT use a proportioning valve on the front brakes. A proportioning valve does not provide a fixed reduction in pressure across the entire range. The harder you push, the less brake force you'll have! You could go with the '88 4-Runner 4 cylinder calipers, which have two 43 mm pistons and two 34 mm pistons, instead of the V6 caliper which has all 4 pistons at 43mm. They both work with the same vented rotor. You'll have a better front/rear brake balance that wouldn't be that far off from stock, but still give you a bit of extra brake torque, and the benefits of a vented rotor. The SX rear calipers aren't really suited for much more than stock front brakes, but they may be livable with the 4 cylinder 4-Runner calipers and the right pad combination. Nigel

Specs show the aluminum Z31 calipers at 9lbs with pads, vs 14lbs for the V6 4-Runner caliper. But the V6 4-Runner has 43mm pistons, vs 40mm pistons in the Z31 calipers. So, you could loose the weight advantage trying to run a large enough rotor (12"?) with the Z31 caliper to match the brake torque of the 4-Runner caliper, if that's your goal. But you'd have improved fade resistance with the larger mass rotor. Nigel

According to the specs I've found on the R31 rear brakes, they use 260mm rotors, and calipers with a 38mm piston. This will produce significantly less brake torque than the 280ZX rear brakes, which have 258mm rotors, and calipers with a 43mm piston. That being the case, this is not an apples to apples comparison, and probably not a good basis to make a recommendation. Also, the narrow 4x4 front calipers that the OP has, with the 43/34mm pistons, only have a slight increase in piston surface area compared to a stock 240Z caliper. So a 1" master cylinder, with it's 30% increase in piston area over the 7/8" master cylinder wouldn't be a good match. It'll only result in a rock hard pedal, and require way more effort to achieve the same brake force. The 15/16" master is better suited. The 15/16" master has been fine even with the V6 4-Runner calipers with the 43/43mm pistons, which don't have that much more surface area than a stock ZX caliper. I've found that you can't make any assumptions about the capabilites of brake components just by looking at them or the model of car they came on. I've seen what look to be huge, 6 piston calipers, but have turned out to only have 4, tiny little 34mm pistons in them! You have to find the specs and do the math to make any meaningful comparisons.

Daddydonuts, I understand your confusion. There is a lot of misinformation out there about brakes, with a lot of assumptions made about various components. Case in point, gutting a '73 240Z proportioning valve. I keep seeing this come up again and again. Beermanpete is right on. Don't do it! As for brake bias, unfortunately, it's difficult to calculate brake torque for a drum brake, since it doesn't increase linearly with pressure. So, it's hard to know what the stock 240Z brake bias is for comparison to your new setup. However, your new combo has ~64/36 front/rear brake torque split, which is pretty close to the ~63/37 split of a 280ZX. Assuming the weight distribution and center of gravity height are similar, then the two cars probably have similar brake bias requirements. The '73 240Z proportioning valve looks identical externally to the 280ZX valve, but the ZX valve might have a different curve. You could try swapping your stock valve for a ZX valve as an experiment, if you're not happy with the bias from the stock valve. Nigel

What about the throttle body spring? The throttle body spring is what is intended to produce the throttle return force. The pedal spring only has to be strong enough to support the weight of the pedal. Nigel '73 240ZT

There is no proportioning valve integrated into the ZX master cylinder, if that's what your asking. The ZX's have a separate proportioning vavle just like the earlier Z's. Depending on the year of your Z (you don't specify), the proportioning valve that came with your car is either at the rear of the car above the differential (~'70 to '72 Z's), or on the left side of the firewall ('73 on). With the ZX rear brakes, you may have too much brake pressure going to the rear brakes, leading to the rear wheels locking up before the fronts = BAD. In that case, the stock proportioning valve needs to be replaced with an adjustable one allowing you to "turn down" the rear brake pressure. FYI, if your Z has the stock proportioning valve on the firewall, and someone tells you just to "gut" it, don't listen to them! This will tie the front and rear brake lines together. Nigel

If you're talking about using the Z32 caliper and Odyssey rotor, just be aware that this will be little more than an aesthetic change. If I got the numbers right, mathematically, that brake combo actually generates less brake torque than the V6 4x4/300ZX combo. Although, the difference is so small that it could be considered insignificant. You might also be adding a few pounds. Even from an aesthetic point of view, you're looking at less than a half inch difference in rotor radius, and it'll still be smaller than the Mustang rear rotor. If you're going to upgrade, the 12" AZC kit would probably only cost a couple hundred more, and give a significant bump in braking performance. Nigel

I've weighed the following: SMM Mustang Rear kit: 25 lbs per wheel Modern Motorsports Xtreme 13" Rear kit: 20 lbs per wheel Drums with aluminum drum: ~ 13-14 lbs per wheel (not as accurate a scale as the other two) An increase in pad radial height will actually decrease brake torque. You're basically moving the center of the pad closer to the center of the rotor, decreasing the leverage. So pad "coverage" isn't necessarily a good thing. Also, friction is effectively independent of surface area, so a larger pad surface area does not equal more friction. Nigel '73 240ZT

McGard Chrome Bulge Cone Seat Style Lug Nut Set (M12 x 1.25 Thread Size) - 3 Packages of 4 http://www.mcgard.com/component/hikashop/product/863-chrome-bulge-cone-seat-style-lug-nut-set-m12-x-125-thread-size-set-of-4-lug-nuts?Itemid=0 McGard Chrome Cone Seat Wheel Lock Set (M12 x 1.25 Thread Size) - 1 Package of 4 http://www.mcgard.com/component/hikashop/product/964-chrome-cone-seat-wheel-lock-set-m12-x-125-thread-size-set-of-4-locks-and-1-key?Itemid=0 I'd avoid anything cheap with an allen key style internal hex. They round out too easily. Cheap chromed lug nut in general will also rust quicker. Nigel

Are there no small machine shops in Barrie? Nigel

Jersy, check out my very detailed write-up on this swap that NewZed already posted a link to. Covers just about all you would want to know, including some of the differences in the transmissions. The later S14 5 speeds are much stronger than the ZX boxes. I think the only thing I screwed up in my writeup was the driveshaft length. I have to remember to fix that. NewZed, Nissan switched to a dual cone syncro on second gear at some point for the SX box. To voong413, any Z clutch/flywheel will work with the SX box, so long as they're a matched set. For example, the Datsun 240mm 2+2/turbo flywheel, clutch and collar work with the SX swap. The SX collar is the same as the 2+2 collar. All the throwout bearings are the same. Nigel

I recommend that you read it. It describes all of the systems on the car, how they work, how to service them and how to troubleshoot. This should be your first step before you dive in and start adjusting things you don't really understand, particularly when it comes to the brake system. A friend of mine serviced the brakes on his car for the first time without reading the service manual. He ended up smashing in the hood of his car and ripping the drivers side door off hinges, all without getting 10 feet from his garage! All of the information is there. Educate yourself. If you still get stuck, then you can at least describe things accurately. Nigel

Do you not have a service manual?

If you just replaced the pads, why did you remove the caliper? Or did you replace the rotor as well? Nigel

I think I've actually seen these in person. Back in 2005, Whitehead Performance in Toronto acquired a 240Z racecar from Japan that had been crashed and sadly left outside to rot. They kept the interesting pieces. I took some pictures, including these shots of the brakes... NIgel

I have a turbo manifold that was warped, and I had the flange milled flat. I carefully ground half of each of the washers to make up the difference in thickness between the intake and exhaust, at least 1/8" in some spots. Both manifolds have held running 15# of boost with no leaks in 10 years. Nigel

That looks pretty high up. Those pumps don't like to pull fuel, and you may have an air pocket trapped there. You can see how low I have my mounted in the picture below. Never had any issues... Nigel

On Hybridz? (I'm talking about converting, not the being nice bit )

The rear strut towers are actually thick enough that you can cut out the slots for the AZC rear top hats rather than chopping the entire top off and welding in the camber plates. I designed bolt-in plates for the fronts. Nigel

Thanks for the confirmation. Sorry I never answered your question from a few weeks back, but I've never actually installed one of these. I'm just going by theory. So, I didn't really have anything to tell you. Nigel

The 73 Z has a current driven tach. Try the 8920 adapter instead.

Is that with the plugs connected or disconnected?

Do the math. A full stock restoration (not a refresh) on a car in decent shape will probably be at least a 1000 hours (~6 months) of work. If the car was in rough shape, then you’re up into the 1500 to 2000 hour range. Custom work adds even more time. But let’s say 1500 hours at $50/hour (which is probably on the low side) and you’re at $75,000, not including parts and materials. People forget or ignore how much time gets lost working on all the little details, especially on a 40 year old car. You can easily blow an hour here and there just trying to get a single broken bolt out. So, a 50 cent bolt just cost you $50. You lose hours trying to track down a part that doesn’t exist anymore, then hours more repairing what you have. There’s the time spent dealing with sub-contractors. Etc, etc. All that time adds up and if you’re paying byt he hour, and you want every little detail perfect, you’re going to get a really big bill at the end. Sure, you could spend a lot less (you can get a paint job at Macco for $250), but $100,000 is certainly not unrealistic, and doesn’t make the guy dumb or foolish. Nigel

Why is he dumb for spending 100k? If that's what he wanted to spend his money on, then all the power to him. Some people don't have the time or ability to do work like that themselves, and labour isn't cheap. A years worth of labour at $50/hour will set you back $100,000, and that doesn't even include parts. He may have had no intention of selling it and never viewed it as an investment. I know I couldn't care less what my Z is worth (other than for insurance purposes), because I never intend to get rid of it. Nigel

He used a 280ZX TURBO drive shaft, which mates with the larger flanged R200. Apparently '75 280Z's, 280ZX Turbos and Z31's have the larger R200 flange. I learned something new... Nigel