C20XE (inj. not carbs.) running temperature - 3 questions

[Darrenkidney]

Hi All,

with the standard thermostat I was running around 95dC coolant temp with easy driving, but it didn't take much either by way of good weather or slightly harder driving to reach 100-102dC and in traffic in good weather 105dC was the norm.

So I changed the thermostat to the 82dC version... and now only in hot weather traffic does it get above 85dC. I also changed the fan switch to 87/82. These changes improved the subjective feeling of a very hot engine and made the driver's footwell much more tolerable in my LHD car where the feet are very close to the manifold (which is wrapped).

The questions:

1. Am I running too cool for the engine's WELL-BEING and should I change back to the standard thermostat but keep the low temp fan switch?

2. Is 105dC too hot for the engine's WELL-BEING?

3. Any other proven options/experience to improve WELL-BEING of the driver's feet :-) 

 

Looking forward to your opinions...  Thanks!

[ScottR400D]

Anything close to 80c or above is fine. My Duratec, and many others run at that.

The only reason for running hotter might be economy. If you're bothered about that. 

[Darrenkidney]

Could it be that the engine management system is increasing the fuel being injected because the engine is "not yet up to temperature" and I therefore get more "pops and crackles" from the sidepipe? It is marginal and very subjective, but reading your comment ScottR400D, prompted me to draw this correlation...

[ScottR400D]

I'm don't know the details, hopefully someone who does will be along but simplistically, as I understand it, running a little cooler means the charge is cooler and holds more oxygen which allows for more fuel to be injected. The lambda sensor measures the oxygen in the exhaust and enables the ecu to adjust the fuel to make the burn as economical as it can at that temperature. 

If you run hotter, less fuel will be injected to balance the mixture which will produce slightly less power but be slightly more economical, reducing emissions. 
It's not something I've looked at too closely but hopefully there'll be someone along who has. 

[Mike Biddle]

Re well being of feet, I suffered the same problem living in Dubai with an LHD car, also an injected VX. My solution was to fit scoops venting into the footwells, which works very well, see the pic below. Note that when this was taken I had fitted a different engine, hence exhausts both sides.

 

[alan c]

Hi I have a similar set up and post a rebuild by Premier Power and mapping by Northampton Motorsport it runs with similar temps to the ones you are now getting so I would say they are ok.

While the engine was out I insulated the bulkhead and tunnel and footwell temps are ok now.

Alan

[JonS]

#1

We do allot of work Bosch engine management systems and anything we've seen since 2004 are configured to be off any cold start cycle at a fraction over 81c you see this in a data line in the ECU that changes so it's probably calculated in in Fahrenheit at 178 F. 
The 20XE and C20XE which you have on your injection car uses an early ECU it on Bosch Motronic 1.5 if it has a distributor or Motronic 2.8 on the later coil pack ignition, I suspect these had much the same cold start cut off protocol as we used to run these with 82d thermostats and had no emissions issues at all. 
Hope this helps. 

[MAURY712]

Hello 

i have done the same setting since 20 years, because i am in the south of France.

C20XE  injection  catalysed   Bosch Motronic 2.8  old 3 row copper radiator ,no oil cooler  exhaust manifold insulated

all seems to be right.

ignition plugs are well colored 

french MOT emmission control is  ok  even at Idle 

often the water temp reach 90c and the oil temp reach 90 100c when we are in fast road or hillclimb .

i have a question too ,is an alloy radiator really intresting ?

thank you

 

 

[ECR]

If your temperatures are ok as you say, you don't really need an alloy rad. They're lighter and look good if that's important to you.