620 engine swap, temp gauge compatibility?

[Valvebounce]

Sorry if this has been covered before. But I'm too fat lazy and drunk to search. 

I'm swapped an sr20 into my 620. Im starting to think about tackling the wiring.  Most of it should be pretty straight forward. But how does the resistance for stone cold and red hot on a 620 temperature sander (single wire unit) compare with the stone cold and red hot resistance values on an S14 Silvia? My poor rig began life powered by a dismal J15.  But I'd wager that the min-max values for that would be the same as the those for a L4 powered truck.

The sr20 sender is threaded, and of a smaller diameter that the 620 one. Which is held in by a nut/sleeve(?) (I think) 

 

The Sr20 is a pretty popular swap, so what had everyone else done?

[Stoffregen Motorsports]

There are a couple ways to deal with this issue. One way is to use the sender that goes with the gauge, I do this on my Toyota Land Crusier LS swaps by tapping a hole in one cylinder head and threading in a Toyota sender. But as you say, the senders are totally different between the SR and L motors. Could there be another spot on the SR to install a sender? Another way is to measure the resistance of the two senders and see if they are the same, if not, maybe you can find another similar threaded sender. If this doesn't pan out, you may be able to wire in a resistor to match the old gauge with the SR sender.

 

I'm sure someone here knows the answer.

[DanielC]

"Another way is to measure the resistance of the two senders and see if they are the same, "

 

Do this first.

[5t341tH]

i swapped a sr20 into my truck as well. The stock temp gauge does work with the sr20 temp sensor

[Valvebounce]

Forgot I started this thread. Hahaha. (I was probably chopped when I started it) 

I dont have the original sender either. I'd honestly prefer an aftermarket guage, as I've always found factory ones to be average.  But the dash is pristine, and apart from an aftermarket tacho it's going to look more of less stock. (I've even got the radio blanking plate in the dash) 

This engine will finish up with an M62 supercharger on it down the track. So good temperature reading is important.

 

Can anyone tell me what the resistance range of a standard 620 sender? I could probably find something the same in the same thread as the SR pocket. 

It would be a PITA to try weld a boss with a tapered seat in it the same as the datsun pocket.

 

[Valvebounce]

It's much easier to go the other way. I once had a pocket made that screwed into an A15 head, and had a female thread to receive the sender for the aftermarket guage on my supercharged B110. (I got that puppy up to 125°C after a spirited session on the burnout pad)