Radiator Upgraded needed......

[Datto-Zed]

Well on the topic of clutch fans (sorry to hijack the thread).....

I want to replace the fixed engine fan on my sunny with a clutch fan....is there any particular fan that I should be looking for? Something that will be a suitable size and will bolt on.

[TRAV-KE55]

Datman,
I run the same radiator as you and have absolutly no probs with it, i can think of a few probs you may have,
1- space the rad back a bit ( even just the side sheilded from the support panal) and seal of around the perimiter of the rad. This will give more of the core airflow & increase the efficentcy
2- make sure the core is cleaned and in good order
3- From your other pics i noticed the car doesnt have a front spoiler, putting one on will give a greater low psi under the car and will cause much much more airflow trying to get throught the radiator to equalize the pressure = more rad effientcy, i have seen this work time and time again.
4- make sure the thermo is turned off at speed, above about 60kph a running thermo will resrict more airflow than can run through with vehicle speed.

Also i agree bill that a copper core is better at cooling but it has its few basic flaws
1- while copper is a better heat conductor it also corrodes as you look at it! this is why they copper cores are always painted black to help stop the corosion (we have all seen the copper core with green stains on the front), once the core is painted they become much less efficeint as the paint acts as an insulator. this is why a good copper core rad is usually so big!
2- weight, we are talking about a race car here & less weight is his advantage, the bigger the copper core the heavier the rad, but also the volume of extra water for the thick/big/un-effeceint painted core is all weight 1lt water is 1KG!
The current rad you run we had to run a very damaged one (run up the back of a porche in practice!) at the island magic, the core had been peppered with stones and we had to block of 4 capilary tubes to stop it leaking, the opperating temp stayed at a constant 84 degrees c while racing.
The rad you have, i have just bought a bundle off new ones i like them so much and sell them to customers for there race cars!
The only thing i havnt taken into accout is the possible power you have. Remember that Hp= heat.
maybe relocate your oil cooler to help as well, you will be supprised how well the still work stuffed in a obscuer spot!
Good to the sunny has hit the track and hope to hear more about it soon.
Hope i have been some help
Travis Robson
ROBSON RACE & RALLY

[TRAV-KE55]

In regards to the sunny engine fan post from DATTO-ZED, try a jap importer or wrecker, a fan of a clutch fan of a nissan vanette witha A15 may help you out (assuming you sunny is still a A series??) You may need to use the water pump as well though as it mat have a different flange for the fan hub!
Good luck
Travis
ROBSON RACE & RALLY

[Datto-Zed]

Thanks for that Travis. I'll check that out (still an A series).

[Datman]

Thanks Travis....I am planning on spacing the radiator back as the first port of call. I don't have time to fit a new one prior to the Datsun Nationals over Easter ...so I will try spacing it back with some ducting to see how we go.

With the spoiler.....I have not decided yet wether or not to run one. It's interesting to note that two of the fastest Under 2L IPRA cars went faster when they remove them...specially at Eastern Creek. They are called air dams for a reason I guess.....they certainly create a lot of extra drag in a straight line, and don't seem to provide much in the way of down force. I hear whatyour saying though about the cooling side of things...but if I need an air dam to keep the car cool...something else aint quite right....better to fix the problem, than slap a band aid on it

Thanks for the tips thoug...I'll report back with the results.

P.S. If I get it done before Sunday....I might go out to Oran Park...they have a private practise day I believe this Sunday.

[BigMuz]

Datman, good timing..

http://www.autospeed.com/cms/A_2455/article.html

Muz

[Gab]

Falcon radiator might be an option.........

[Datman]

Thanks Big M....I'll certainly have a look at the link.

[Datto-Zed]

Bigmuz, Edo and all other members of the Cult of the Clutch Fan Fans:

What are your thoughts on fixed engine fans (ie no viscous clutch) vs thermo fans?

[BigMuz]

Bad. Clutch means:

Automatically spins harder when hot (or at least when very hot)
Limits ultimate speed of fan
Allows use of a very coarse pitch fan so idle speeds still draw through plenty of air
-therefore allows drive ratio to be optimised for lower water pump speeds

Using a fixed metal fan is nothing as good as a good clutch fan. Constant load, constant speed. I have seen the flex fans come apart and that is not real good...

Hope this helps (lol)

Muz

[Datto-Zed]

Mate, you must really hate thermofans!