View unanswered posts | View active topics It is currently May 14th, 2025, 1:49 am



Reply to topic  [ 6 posts ] 
 Fan air speed 
Author Message
Firing on two.

Joined: May 26th, 2010, 5:34 pm
Posts: 109
Post Fan air speed
Has any one worked out the speed in mph that air is pulled through the fan on a 2cv per 1000 revs if stationary .. do the racers remove their fans or modify them.. is there a road speed at which air is pushed through faster than the fan pulls it through..fan only has blades on the out side of the center dome with no fan (just a belt pulley) would the funnel effect push even more air through at speed .. Lomaxes have no cowling on at all and they seam to survive .. Is the fan just there for slow traffic


Last edited by notsmartcar on February 17th, 2011, 11:49 pm, edited 1 time in total.



February 17th, 2011, 11:13 pm
Profile
Firing on two.
User avatar

Joined: June 19th, 2010, 8:40 pm
Posts: 761
Location: Kingswood, S.Glos.
Post Re: Fan air speed
With the 2CV standing still or doing 60 mph? Or against a gale wind?

Now you've edited your post Notsmart, my reply is superfluous :lol:

_________________
John Jordan

It is a truth universally acknowledged, that a single man in possession of a good fortune must be in want of a d'olly.


Last edited by knightley on February 18th, 2011, 12:33 am, edited 2 times in total.



February 17th, 2011, 11:15 pm
Profile
Firing on two.
User avatar

Joined: December 26th, 2008, 9:40 pm
Posts: 3332
Location: Surrounded by 2cvs...
Post Re: Fan air speed
notsmartcar wrote:
Lomaxes have no cowling on at all and they seam to survive ..


Lomaxes have the barrels & heads hanging out in the wind, unlike 2cvs.

_________________
Image
Zookeeper of a miscellany of motorised silliness - from 0.75bhp to 9ft tall - now living life on the road in an old VW.
http://WhereverTheRoadGoes.com


February 18th, 2011, 12:07 am
Profile YIM WWW
Firing on two.
User avatar

Joined: November 4th, 2009, 4:00 pm
Posts: 526
Location: Confederate state of South Yorkshire
Post Re: Fan air speed
notsmartcar wrote:
.. Is the fan just there for slow traffic


No .....I've had the pulley break and tried to drive the last few miles to my destination,the car soon started overheating [was a Dyane, btw].

T.

_________________
Remember .....the drive is the reason,the destination is just the excuse.
2CV6 Special [Red]
C4 VTR+ Coupe [Black]
C1 UrbanRide[Blue & Orange] {Ltd Ed}


February 18th, 2011, 12:19 am
Profile
Agony Aunt - You have a car problem? Speak to Ken

Joined: March 6th, 2009, 1:40 am
Posts: 3675
Post Re: Fan air speed
Kevin,
this should keep you busy for a while... ;)
< http://www.offroadvw.net/tech/wes/fan.html >

On UK racers, the fan _sometimes_ has 3 blades removed, but from what I've seen, that's OK for sprint races but not for enduros.
(Edit. As Terry mentioned, because the engines are cowled, they will overheat very quickly if the fan stops working.
2 or 3 laps of Snetterton without noticing that the fan's bust, before engine problems are likely.
)

Some Belgian 24 hr racers run without fans in the prototype class, but add some fairly large oil coolers to compensate.

In the standard class at Spa last year, I'm sure that a couple of the cars were running with grille muffs fitted, but it was seasonal weather for the Ardennes in Autumn.

ken

p.s. Lomax in a traffic jam in hot weather, switch the engine off?

_________________
Image


February 18th, 2011, 12:23 am
Profile
Firing on two.

Joined: April 22nd, 2009, 11:06 pm
Posts: 3684
Location: Ecosse
Post Re: Fan air speed
notsmartcar wrote:
Has any one worked out the speed in mph that air is pulled through the fan on a 2cv per 1000 revs if stationary .. do the racers remove their fans or modify them.. is there a road speed at which air is pushed through faster than the fan pulls it through..fan only has blades on the out side of the center dome with no fan (just a belt pulley) would the funnel effect push even more air through at speed .. Lomaxes have no cowling on at all and they seam to survive .. Is the fan just there for slow traffic


there are all sorts of modified fans and theories (after a bump our car lost its blades and gained about 3hp which took it up to the front of the pack....for a bit :lol: ) and even some rather~ erm ~"autistic" views on whether the ducting should be the full depth of the fan tips and the outside radiused for more efficient air flow :?

in traffic the engine is just idling and youll notice that the heater doesn’t. therefore the engine is running cold.

on motorway the heater melts my left boot therefore the engine is hot

in winter it needs restricting so if anything its over cooling. However its not going to end up in catastrophic failure because its running slightly cool.

Id leave it well alone unless you had a engine temp monitor and then you can work out what needs most cooling when and when your in the danger zone.

bit of waffle!- no i dont know the air speed of the cooling fan at specific RPM or the L/Min for that matter it just works

Sean

_________________
Kissing the Lash
Image
"Any advice of a technical nature is given on the understanding that I've actually done this shit, not just read about it in D*lly club mag some time ago.


February 18th, 2011, 10:19 am
Profile
Display posts from previous:  Sort by  
Reply to topic   [ 6 posts ] 

Who is online

Users browsing this forum: No registered users and 347 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
cron
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group.
Designed by STSoftware for PTF.