Retro fit cold start sensor

[MrPerkles]

Has anybody got a solution for a cold start sensor mounted to cylinder three ,I need to fit one as part of my EFI project and dont really want to drill into the head.
Thanks for your help

[stlrj]

Originally Posted by MrPerkles

Has anybody got a solution for a cold start sensor mounted to cylinder three ,I need to fit one as part of my EFI project and dont really want to drill into the head.

Maybe you mean a cylinder head temp sensor (CHT). You migh try a CHT ring that fits under the spark plug like they use in a general aviation engine.

[purplehaze]

Instead of a CHT sensor, you might try going with an oil temp sensor.

That worked when I went EFI.

Let me know if you need the Clewett aux air regulator/cold start valve. I have one new I won't need.

[stlrj]

Originally Posted by purplehaze

Instead of a CHT sensor, you might try going with an oil temp sensor.

That worked when I went EFI.

Let me know if you need the Clewett aux air regulator/cold start valve. I have one new I won't need.

EFI might need something that heats up faster then an oil temp sensor.

[MrPerkles]

Thanks for the replies guys,the ecu I am using uses a water temp sensor and needs to go as close to the head as possible oil takes longer to heat up.
Its a two pin sensor ,I am interesting in the spark plug ring any more details ?

[safe]

I have seen pictures of a sensor just being clamped on a cooling fin. It may have been in the ~"ST EFI kicks ass" thread.

[David]

I can't help with the spark plug ring except to say some Yamaha KT100 kart engines use them.

I see you want to keep the sensor near the head, but here's where I put my sensor and where many others have:

[safe]

First page: EFI Kicks A$$ - the ST goes electric

[purplehaze]

Clever idea, with the cooling fin clamp.

Mine was similar to David's, except I chose the top of the thermostat housing. It's the first step after the oil pump, even before the cooler (or in my case, secondary oil filter).

Any of these locations should work to obtain the temps for the cold start.

Good luck!

[MrPerkles]

cheers guys the thermostat location is the easiest route but my last resort,I like Mr Novaks solution I just need to think how to fit my sensor this way as its a brass cylinder.
I will post my efforts after the weekend

Thanks again for your replies

[Jeff Alton]

On my EFI motor I use oil temp for the warmup maps. I don't have it dialed perfectly yet but it starts and never stalls regardless of temp..... Most ECU's allow you to adjust temp maps ever few degrees and that is plenty of accuracy.

As for where to mount the oil temp sensor? I searched and got conflicting advice, so I mounted two. One is in the thermostat housing and one is in the 1/2/3 timing chain cover. I only run one at a time but back to back testing shows they both read the same. They also read consistent with the factory dash mounted gauge....

Cheers