Cooling

[Freddy Backup]

I have a Firenza rally car that has approx 150 bhp that is fitted with sump guard and the rubber splash guards of around the suspension to prevent it from drowning out in fords etc. Have had the car for many years the only problem I have never fully resolved is cooling when the car is stationary - it eventually overheats. I assume this is becuase the air from the rad can not get out - it has two electric fans. Above 20 mph no problem at all. All cooling parts are in good condition rad, water pump etc.

Looking at old pictures the race cars had slots cut in the bonnets - like alot of modern day rally cars such as Evo's etc. Is this the solution

Am I missing something? - Has anyone else got any other ideas? Overheating - its it something that all old cars do?

[Doss backup]

I have seen 2.3 vivas with a large square section cut out from the center of the front valance where the rad is, this has then been replaced with a criss cross paterned wire mesh plate which would let a lot more air around the rad. A bit drastic though.

[northernutter Backup]

I no its a rally car but do you have a heater in it?
I have a GT and if i leave that sat yes it will over heat, so when ever it is just sat there i turn on the heater in fact if i am on a long run and the weather is hot i have to put it on, its like haveing an extra rad.
As for the bonnet any vents can only help.
Deon

[lambaj]

Sounds like a rad cooling capacity issue to me.
Does the car over heat only after idling after a good thrash, or will it boil up from cold if just left ticking over.
On idle, an engine only produces a fraction of the heat it does working hard, so even a small rad would cool it with fans running at idle from cold.
If it only boils up after a run, then its an air flow issue as the heat energy stored in the hot metal in the engine needs to be lost by the rad. If there is not enough air flow, then even a large rad will not cope.

Silly question. Have you got the fans blowing in the right direction, and are the fan blades turning the correct way ? I ask as a lot of people do not realise that a fan blade is designed to work in one direction only as will be much less efficient if run backwards, hence the fans are sold as "draw through" or "push through" This might explain why your ok on the move, and boil up when you stop.

I have a supercharged V6 3 ltr in an HA, and that is kept cool enough by a fiesta diesel rad and two 10" fans......

Good luck

Tony