The V8 Owners Forum -

This opens at 78°C but I can't find a picture of one - does anyone know if it fits?
The diameter is about right but the length given is about twice that of my current thermostat.
http://www.ebay.co.uk/itm/351473552990? ... EBIDX%3AIT

I always run Mini summer 74 degree stats in mine.

Any particular reason for choosing 74°?

It keeps the RV8 running cooler which may be an issue when it is in custom/kit cars with limited engine bay space or limited airflow

ratwing wrote:Any particular reason for choosing 74°?

As there is no point running an engine hotter why do you need 78 or higher? If I could find a 70 degree stat I would fit that.

Darkspeed wrote:

ratwing wrote:Any particular reason for choosing 74°?

As there is no point running an engine hotter why do you need 78 or higher? If I could find a 70 degree stat I would fit that.

I was going to replace my jammed 78° stat with another but couldn't find one so fitted a spare 82° stat I had in the garage. (similar dimensions but can't remember what car I'd bought it for)
I don't think its overheating but perhaps it doesn't seem to run quite so well as with the cooler stat?
I've got a new 74° stat (a spare from my old Land Rover) so I'll fit that instead.

Darkspeed wrote:I always run Mini summer 74 degree stats in mine.

Do you drill a hole in it?

Denis247 wrote:

Darkspeed wrote:I always run Mini summer 74 degree stats in mine.

Do you drill a hole in it?

Depends on if I think its needed really so many different applications.

Darkspeed wrote:

Denis247 wrote:

Darkspeed wrote:I always run Mini summer 74 degree stats in mine.

Do you drill a hole in it?

Depends on if I think its needed really so many different applications.

Well I assumed you were talking about your Rover engine when you said "in mine".

Why do modern engines run hotter? lower emissions? better fuel efficiency?
Surely the optimum engine temperature is the design temp which the engine has been built arround for machining tolerancing?

Tom.

Denis247 wrote:

Darkspeed wrote:

Denis247 wrote:

Darkspeed wrote:I always run Mini summer 74 degree stats in mine.

Do you drill a hole in it?

Depends on if I think its needed really so many different applications.

Well I assumed you were talking about your Rover engine when you said "in mine".

I have had quite a few and they have had different manifolds and cooling layouts and in every engine that I have owned (mine) I use 74's and sometimes I will drill a hole and sometimes not depending on the manifold type and the colling system installation.

I believe modern engines run hotter for reduced emissions - it's why the 4.6 Rover has a hotter stat than previous capacities.
I always drill a hole about 4mm in the flange and fit the it with the hole at the top - I reckon it helps get rid of air bubbles behind the stat. Some have a hole and jiggle pin which is supposed to keep the hole clear but I always remove the pin, partly because I've never seen the bleed hole blocked on any of my thermostats and partly because I don't want the little bit of brass blocking a rad tube or getting into the pump if it becomes free.

ratwing wrote:I believe modern engines run hotter for reduced emissions - it's why the 4.6 Rover has a hotter stat than previous capacities.
I always drill a hole about 4mm in the flange and fit the it with the hole at the top - I reckon it helps get rid of air bubbles behind the stat. Some have a hole and jiggle pin which is supposed to keep the hole clear but I always remove the pin, partly because I've never seen the bleed hole blocked on any of my thermostats and partly because I don't want the little bit of brass blocking a rad tube or getting into the pump if it becomes free.

Likewise I always remove the fitted 'jiggle pin', not just because I don't want it to end up circulating in the system, but the end is a nylon blob, which effectively blocks the hole under pressure from the water, and I want a little water circulating here to ensure there's not a slug of cool water trapped that could delay the opening of the thermostat.

I had an Uncle who was a seriously Old School motor mechanic and he told me to remove the stat from the car, cut the spring and gubbins out of it and stick the body back into the engine to act as a restrictor for flow.
To be fair, it didn't freeze where I lived at the time, but my 1275 Mini seemed happy enough with the change.

Seems to be a case of overheating is bad, therefore running cold is good.