Miles

Bueller? Bueller? Bueller?

New one.............................

Time to pull the differential and remove the cover to see what is going on. If the differential is toast then replace it with another used R200 with the same gear ratio. Gear ratio: rotate the ring gear until you see two numbers separated by a slash ( / ) or colon ( : ). and divide the larger number by the smaller number to give the ratio. Most likely you have a differential with a 3.54 ratio. Verify.

Always post the year of your car and what modifications it has. Search is your friend. I found the following posts in Hybridz in about one minute.

Could the orange wire be for accessaries you want on with the engine off and the pink wire powers the ignition circuit. On the back of the ignition switch are there separate terminals for ACC and IGN?

Looks like a drive by question.

Look for a company that rebuilds brake components (not a brake service shop) and see if they can rebuild it for you. This is what I did when I couldn't find a new 280Z booster. I bought a booster from a local junk yard and had a local brake component rebuilding shop rebuild it. I recall from about ten years ago, that Cardone used to provide this same service where you have O'reillys ship them the part, they rebuild it and then ship it back to O'reillys. For example, I took a leaking master cylinder to O'reillys and they shipped it to Cardone. Cardone rebuilt the MC and shipped it back to O'reillys. If you live in, or near, a big city there may be a company that rebuilds brake components.

http://www.zcarparts.com/ 280z 8.5 inch dia booster https://www.rockauto.com/en/moreinfo.php?pk=29330&cc=1209226&jsn=888&_nck=miHVm5QT%2BfyI%2BeUfiZtyKNQxXgzz29sg6NVuCDdjB80aVw2id8isb3egjdMgkO5dV1oWSHheXD2pR3Wyr%2FouBEjLxg2%2Bry8AAeOScUKohl5AUGSzhV8%2Bu6ubQOoKqXIE7WqsMvDu7%2F2bwVsqMJP1TFO3CJTY5QOPN%2F9Ja%2BVRmxfaZthYdfBSFOWKrzblb5JtRxAnjrC3zjfG3Lp2WzDqEkt6QBXnMiDGirTeZi5UY5UBYThQXDe2M1oFHBXcCFs0gyj%2B42OXJ1C9MiRdAIrGdg9820EI5Paj0Vs9cPN1bESavgD5%2BoF9fWE0Xi8zhjZE6w3ksAh49ZVuguGgYit3%2F%2B6phzXvYSdPR2NrzObies3wcyflvWLfc3S0NPD09%2BOjMP6sxJs7CrH0F7SmlgtmnCVnwCqf%2BR6Q

Try the math as a starting point.

The 240z does not have a relay built into the dimmer switch. It is just a a piece of copper that switches between the high and low light circuit. If you examine a 240Z combination switch you will see that the contacts are just small, thin, pieces of copper bits which are subjected to heating and pitting from arcing when a high amperage load is supplied. Headlights pull high amps across those metal bits in the switch. Using relays for the headlights takes the high amp load off of the wiring and those copper contacts inside the switch. For over 40 years Z owners have reported having their combination switch melt due to high amp loads. So yes headlight relays are a good idea. Many Painless harnesses have been installed in Z cars so it is likely that there is a relay write up on HybridZ or at ClassicZcars.com. Benefits of headlight relays: Less stress on wiring and the combo switch The lights get a full 12 volts You can run higher amperage headlights such as H4s etc Note: A relay for the electric fuel pump is also a good idea.

Would a block hugger exhaust manifold work?

Could be battery/alternator related if the car sat a long time. Take the battery and alternator to Oreileys or Autozone and have them checked out.

Changing the MC will not damage the booster. Your booster has failed internally or you are not getting vacuum from the engine. Suggest that you inspect the vacuum hose and fittings between the intake manifold and the booster. Verify that you have vacuum at the booster connection.

Drain the differential and check for metal particles. Another possible source of a clunk:

I had three Wilwood MCs fail right out the box. Two of them leaked internally and the third MC had smashed MC bleeders. I ended up purchasing a 79 280ZX 15/16 MC from Dave at Arizona Z Cars for about $125. Good deal. The last time a reaction disk fell out I made a new one from a rubber stopper and used JB Weld to glue it to the push rod. Please post how you get things worked out.

No.

The hissing sound suggests a failed booster. After you test the booster per my previous post, and it fails the test, replace the booster. Typical booster installation errors include push rod adjustment and/or the reaction disk falling out. See the brake FAQ and brake forums for details. Suggest that you read up on push rod adjustment and the raction disk.

Sounds like a booster problem. Check your booster and vacuum hoses to the booster. Also, make sure that the check valve is installed correctly. Check that the push rod between the MC and the booster is adjusted correctly. Booster check: With the engine off, place your foot on the brake pedal and apply pressure like you are trying to stop the car. Hold that pressure. While still applying pressure on the brake pedal, start the car. You should feel the brake pedal sink a bit and become softer to push. It means that the booster is working. If the pedal remains hard to push during the test then there is a booster issue. Most likely the booster is leaking or it is not getting vacuum from the engine. The other cause of a stiff pedal would be if the MC push rod is adjusted too far out such that it is pushing the piston inward in the MC. What happens is the piston gets pushed past the the point where the the fluid return port is covered so fluid gets pumped out to the brakes but can not return to the tanks when the pedal is released. So the brakes become locked. If this happens you can relieve the pressure by opening the bleeders on the MC.

How to make Dave's headlight harness: http://www.zhome.com/DaveRelay/DaveBuild/DaveInstruction.htm

Motor Sport Auto (MSA) in California sells carpet kits. https://www.thezstore.com/page/TZS/PROD/classic08g06c/40-2584

http://www.thecarburetorshop.com/Carburetorsizeselection.htm

http://www.thecarburetorshop.com/Carburetorsizeselection.htm https://www.speedwaymotors.com/the-toolbox/what-size-carburetor-do-i-need/28634

Can't open pictures.

Would like to see pictures of the engine bay wiring.

The Painless install is documented throughout HybridZ and on the web. Suggest that you purchase a copy of the Jags that Run 240Z V8 conversion manual (link below). Buy the book How to Restore Your Datsun Z Car by Wick Humble. It will save you hours of searching for "how to" info. Suggest you buy a book on auto electrical wiring such as the one pictured below. Here are some links that may be helpful for your project: https://forums.hybridz.org/topic/29786-painless-harness-to-z-column-harness-headlight-combo-switch/ https://www.datsun-240z-upgrades.net/ http://zhome.com/ https://www.zcar.com/ http://www.classiczc...com/index.html/ http://www.zcarparts.com/ http://www.arizonazcar.com/ http://www.jagsthatrun.com/index.html https://jagsthatrun.com/products/jaguar-v-8-conversion-manual?_pos=1&_sid=5f8e0c2e4&_ss=r