The V8 Owners Forum -

Hi all readers,
I have here a RV8 with a R/R V8 radiator and a P6 pump.
The fan is a 17-inch s/steel fixed fan..
At a standstill the temp soon rises above normal so I have fitted a 10-inch fan on a temp basis in front of the rad, though on the front of the rad it is sited close to the output of the radiator.( no space engine side ) This fan will hold the temp and stop it reaching overheat.
Obviously the temp under the bonnet gets very high and I would like to introduce a better air circulation system which would help in keeping the temp down.
Would the entire system work better with ( say ) two vents in the bonnet reverse fitted and a large electric fan instead of my fixed 17-inch fan.
The vents reverse fitted would let air out of the bonnet when at a stand still as the electric fan would in effect be pushing the air through the vents. When on the move the air passing over the bonnet would create a vacuum effect and pull the air through the vents.
Your views please ...... many thanks, mike

What you suggest should certainly help

How far from the rad is your fixed fan? And is it shrouded?
There could be a lot of air being moved by your fan that is not bring drawn through the rad read churning the hot under bonnet air

A close mounted high volume electric unit should work well


Always good to make sure the air can escape after it has been through the rad

Ian

As a reference point, I have had the following engine-driven (viscous) fan / rad setups:
16" Range Rover classic fan + LDV V8 radiator
17" Range Rover P38 fan + LDV V8 radiator.

Neither needed extra cooling.

Chris.

Is the 17" properly cowled ?

Big mechanical fans usually shift a fair amount of air. Their only real downsides are they sap power at higher rpm's

If it's an engine transplant into a similar layout car, it seems strange the standard fan from the new engine isn't enough? Is the rad a lot smaller?

Hi all and thank you for your comments.

The fixed fan is 15mm from the rad, however it is only partially shrouded and as commented would be driving some air toward the side. Available space will not allow a viscous fan hence the P6 pump.
Stevie, Your right of course about fixed fans sapping the power, but hey its only a 3.9 and if the fan cost me 5 horses I probably wouldn`t notice as that fan has been fitted from the start - however I get your point and it would be very nice to reclaim those said 5-horses.

From the answers given to the topic I need to fully shroud the fan, the rad a lot bigger and thicker than the old Ford V6 2.8 type creates the problem of finding a shroud that will fit where needed. The general idea was to not improve the shroud ( what there is of it ) but improve air movement front to back by releasing the blown air better with the reverse fitted vents. The rad is from a R/Rover V8 with the two oil coolers one each side.

Assuming a properly fitted shroud, would I need a large ( say 16-inch ) fan or would I be better off with two smaller ones? The main problem is space, a viscous fan is out of the question and the P6 pump would result in a electric fan having to be fitted "off centre" hence my idea of two smaller fans of (say) 10-inch.

Thank you all, Mike

Mike

Do the checks but I am fairly sure you will find a single 16 inch fan will move a lot more air than two 19 inch ones

The more airflow the greater chance you have of extracting heat and moving the hot air from the system

Ian

I think as always, a picture of what you have would be very helpful.

Regardless of fan type, it should always be shrouded so any air to/from the fan, is directed through the radiator core. Just look at how any OEM do this with engine mounted fans

Electric are similar, although aftermarket tend to mount directly to the core. This helps with space, but actually means air is drawn through a much smaller area of the core than would be with an OEM type shroud/fan

Hi Stevie, Sorry but the only picture I have of the engine bay is frontal and only shows the fan guard at the top, I have a little shrouding on the sides, clearly not enough of it though.

I will explain exactly the position of the rad - you would know this better than most being a Granada Mk2 owner. I obviously needed more space front-to-back in the engine bay and I found I needed a further 50mm. I am using SD1 engine brackets, the main part only these line up perfectly with the old V6 rubber mounts though a 10mm spacer was needed between brackets and rubber mounts.The panel that carried the V6 rad was originally angled ( closer to the front at the bottom ) and shrouded bodywork wise from the front, All I did was remove the rad, measure 50mm from the engine side at the top and slice it straight down. This created a sharp edge on both sides due to Ford made holes already there. These edges had angled ally attached using rivets thus preventing a sharp edge from damaging the Range-Rover V8 rad that was fitted. The space left after the engine was fitted did not allow for a viscous type pump so I used the P6 one, hence a fixed fan.
The problem I have left for myself is the pump is in line with the middle of the rad and being a bulky thing a electric fan would need to be fitted off centre or be very thin.
An off centre fitted electric fan would need a shroud making to fit the setup or a ready made unit altered.
The cutting mentioned above is the only alteration I have made or needed to do to the cars bodywork to fit my conversion, though close to the firewall it isn`t tight.
I am now looking at (say) a 16" or above electric fan probably off centre fitted BUT shrouded completely.
The problem of under bonnet heat though is still there and the two reverse fitted vents in the bonnet would I think help take a lot of that heat away.
As a Mk2 owner yourself ..... would I be getting close to removing the heat?
Regards and thanks, Mike

Again, without a picture hard to say.

I have a custom rad, isnt overly huge but it does fill the frontal space, but it does also have a huge intercooler in front of it.

I have one large 16" puller, and a smaller 6 or 7" motorbike fan to the side of it. Was all I had room for.
This does seem to keep my LS under control under pretty much all circumstances.

I think the biggest factor is just ensuring proper cool airflow. ie, no hot air can recirculate, and only cold air gets drawn through the rad itself.

Yes a couple of vents would help I'm sure, I have some myself. But the Granada bonnet has pretty big panel gaps around the sides anwyay

Hi Stevie, Many thanks for your reply and help.

The plan of action then ......remove s/steel fan, fit a 16-inch electric fan that will have to be fitted off centre ( unless I can cut even further forward - at a push ) and fully shroud the fan.
Then and only then if the temperature stays in check I can forget about the vents.
Or to put it bluntly - do the job properly and open the wallet

Cheers Stevie, Mike

Ian Anderson wrote: I am fairly sure you will find a single 16 inch fan will move a lot more air than two 19 inch ones

Are you sure there Ian??

I recently bought a 16" Kenlowe fan and it does shift air - it's a two stage fan so check wiring and amps per circuit at 24 peak. It was £120.

It's also 75mm deep.

Cobratone wrote:

Ian Anderson wrote: I am fairly sure you will find a single 16 inch fan will move a lot more air than two 19 inch ones

Are you sure there Ian??

Typo there

Should be 2 by 10 inch fans

Ian

Hi Guys,
The Kenlowe sound fine, however at 75mm that would have to be an "Off Centre" fit, forward space is at a premium, I`ve got 60mm absolute maximum allowance and that would leave just 10mm between fan and centre of a P6 pump. So its a off centre fit or two smaller fans.
Perhaps 2 x 10-inch would be better due only to space. Whats your view on fans that have the curved blade as apposed to the straight blade type? Retailers seem to think the curved bladed fans shift more air than a straight bladed fan of the same size - seems to make sense.
Fully shrouded in both cases.
Regards ... mike