you can go to any fitter and turner they will make a brass adapter to suit
I bought one off slovakia store on ebay it had one side with the thread I needed
but needed the other modified and cost me very little to get it done at a shop.
Temp is vital you get it right for obvious reasons.

This one uses a collar nut





This one does not use a collar nut

Those photos are not related to the speedometer ????

* Yes, all Datsun A-engines use the same threads
* I would use an adapter instead of a collar nut
* A "collar nut" is used by the stock sender, but many aftermarket stock-replacement senders do not use it
* When using an aftermarket temperature gauge, have you tried using the stock sender?

The thread of collar nut is the same for A12, A14 and A15 Cylinder heads?


I have test the m16*1.5 nut on a A12 Cylinder head

My actualy cylinder head is similar to the enclosed image with no collar nut i need the collar bexcause i have changed the all gauges and i will need install the sender wich cames withe the temp gauge

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Hi!

I have just received the M16*1,5 collar nuts, but doesnt fit, is to tight the older one fits well on A12 HEAD.

Comparing The thread seems to be diferent. One is made of steel other is another material made? Makes any diference?

Any help

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* NPT is not metric
* Instead of measuring the hex, NPT is based on the threads
* NPT is tapering pipe thread, like the oil sender threads
* Temp sender is not tapering pipe thread, it is metric thread

You can buy an adapter from the gauge company. For example http://www.summitracing.com/search/?keyword=1/8+npt+adapter

1/8 NPT means 3.175mm?
3/8 NPT means 9.52mm?

I dont understand the sender they say is 1/8 npt
the outside coollar 3/8 npt

Myy measures dont match anything?
The original coolar has less than m16

Please clarify my confused mind?

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Hello i bought new gauges to my Datsun 1200 from speedhut


I have on doubt: All A12 A14 Cylinder head has the the same port thread m16 * 1.5? to the temperature sender

THE temperature gauge cames with 1/8 npt female and 3/8 npt coolar nut but doesnt fit

i must buy 1/8 27 npt Female to m16 * 1,5 male, correct? With thin walls

Any sugestion, or where i can find one?

Thanks

Luis

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You are right that the speedometer or drive gears do not tell how many revs/distance. The engineers at the car company figure that out, then specify the appropriate cable-drive gears to be included in the transmission

For example, Datsun 1200
* with 21.7 inch diameter tires and 3.9 final drive: 17T speedometer drive gear
* with 21.7 inch diameter tires and 4.1 final drive: 18T speedometer drive gear

280Z is similar: with different size tires and/or final drive ratios, different transmission speed gears are used

Bottom line: Same speedometer is used with different size tires. The drive gears are changed to match. For Datsun 1200 4-speed, the factory had these gears available: 15T, 16T, 17T, 18T and 19T gears ... allowing you to use different size tires and still have the speedometer read correctly

Hey DD, how would having the drive gear in the transmission help the speedo read correctly? It still can't tell how many revolutions the wheels have compared to distance covered, can it?