Zed Head

Perfectly? That seems unlikely. It's odd enough that a British thread pitch would be used on a Japanense car in the late 60's/early 70's. Why would British be used on the block and US on the balance tube? Chaos! Your thread chaser might cut some new threads though. People have used NPT in the oil pressure sender hole and made it work. Soft metal will distort.

Here's a puzzle for somebody. Comes with a car cover. No reserve. https://bringatrailer.com/listing/1971-datsun-240z-330/

Read the articles here about the GM HEI module, if you find that your wiring is smoked or the factory Transistorized Ignition Unit (TIU), aka ignition module, is gone. You can run wires in the engine bay directly from that terminal block with the green and red wires. https://www.classiczcars.com/articles/electrical/

Is BSPT a possibility? The prevailing internet Z forums' "wisdom" is that the oil pressure sending unit holes are BSPT. JIS VS BSP: What's the different ?Before choosing a suitable thread standard, it is necessary to understand from various aspects. This article will introduce the difference between JIS and BSP, so that you can better choose the thread

Sounds like you're saying things have been just fine then something changed. As opposed to the brakes having always bothered you. If it was mine I'd find the source of the sudden problem before "upgrading" anything. Otherwise you could add the upgrades and end up with the same problem, never solved.

They run up to the ignition module. The module uses the signal from those wires to know when to create spark. Looks like this. Has many wires connected to it, including those green and red ones.

Pre-Fleetwood Mac Fleetwood Mac.

Here's a decent relay instructional video.

You can add a relay as cgsheen suggests, which will take the current to the solenoid out of the switch, or you can bypass all of the inhibitors and other safety features. I would start by checking for voltage on the wire that comes from S on the ignition switch when you turn the key to Start. If there's none there then you need an ignition switch. If you have voltage then you can add a relay or by pass each safety on the path to the starter solenoid. It would be best to also test under load, using a test light that draws some current, like a taillight bulb. I have found that the staked pins (copper color) can get loose and lose contact with the terminal. I had a 78 switch that would grab the starter then let go as I turned the key. The pin was loose. I fixed it with a hammer and a chisel. The terminals are marked with molded in letters. Look closely if you remove yours.

Edit - the author apparently didn't know that the history was documented and easily verified. @Carl Beck From his web site - 1975 - Sold to Kenneth E. Logan D.D.S. - L.A., Calif.. Driven for a couple years then stored away. 1998 - Sold to Michael W. Pretzer. Michael decides to continue his education and sells to Carl Beck. 1999 - Purchased by Carl Beck - who will restore it to original "BRE Racing Trim" 2007 - Restoration to "As Raced" condition completed

Odd story. Purchased and restored to street form by a dentist. " : in the garage of a dentist who had purchased it in ’73 and returned it to its somewhat original street-legal state. " The show is next Sunday in Florida. Ponte Vedra Auto ShowPonte Vedra Auto ShowThe Ponte Vedra Auto Show | Sunday, November 2nd 2025. Presented by O'Steen Automotive Group, Art 'n Motion, & St. Johns Chamber of Commerce.

Excellent job reinvigorating a seven year old post!!! You're exactly right, things always come around again!!! Do you have bondo in your roof? How is Jan? Say hello to Dwight!!!

Good point!! 😄😁😆 What kind of car do you drive? Does it have bondo in the roof? ☹️

Nice catch. I read that comment but it was so bland that it was almost invisible. Thought it was a person commenting just to comment.

https://www.samuri.uk/the-register