[spuggy]

My Motec conversion got a VDO sensor in the left chaincase (where the TTS used to be) for oil temp. This seems to correspond well to oil temp readings on the dash gauge - but I found it useless for warmup compensation as it took far too long to register temperature increase (think how slowly the oil temp gauge in the dash rises after starting to drive the car).

As a result, the motor was quite obviously getting warmup compensation trim for much longer after cold start than it actually needed.

I used the TurboKraft CHT kit, that adapts a 3.2 CHT to a plate that slides between the cooling fins on the rear cylinder on the left - #3 I believe, the one that has the scavenge pump on a 930 anyway. Which you'll need to remove to get the tin off, if you've got one. And re-index/reset, if you've got a cam sensor in yours. Sigh.

You modify the engine tin slightly (cut a slot to allow the plate to pass through), but this can be removed/refitted with the motor in the car. Although you'll likely curse your induction system and lack of quadruple-jointed forearms more than once in the process, as it's fiddly/obscured...

IIRC, there's a small chamber that the CHT sensor screws into; you fill this (most of the way) with oil (or AT fluid, I forget), so there's good thermal contact rather than air/splash to the sensor. You have to fit (eg "notch" and "file") the plate to allow it to slide between the fins (this might actually be due to the bottom plugs come to think of it). I used a liberal smear of a good quality (Arctic Silver) CPU thermal grease.

It works very well for me; I see CHT readings rising immediately after start, and I pull wamup compensation out by 60C - which is a few, like 2-3, minutes running time, tops. By which time the motor is running well without. My only concern is the high CHT numbers logged if you let the motor idle for 10 minutes or more, so I try not to do that...