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The 1957 Dope Dauphine

I will double check it shortly dave. I think I just wiped it away last night.


the general consensus seems to be that nearly all classic rear engined water cooled cars had a small rad and a fixed fan to draw air through as air flow alone isnt good enough. You can get away with having the rad in weird places if the air is forced to go through there. And most that have upgrades where they run hotter move the rad to the front. Hillman imp, r8, dauphine all seem to push the rads upfront when the cars are used heavily or tuned. Have I just been naive in thinking I could go against what people were doing 30+years ago 🤷🏻‍♂️
 
That’s was my understanding, but not my place to piss on your parade, thought it might work with a big enough rad, perhaps be happier once on the move, bit hairy in traffic perhaps.
What’s move now?
Can you remove spare wheel carrier and get a rad in at 45 deg, give it a mouth?
GTA’s run rad at an angle, wider than you’ll get in, but 2.5T/3 litre atmo....you’re only cooling an 1108cc?....curved Hayabusa rad? Otherwise you into cutting boot floor etc
 
No its worse when traveling and in motion, the rad looks to cope with it at idle fine just. A very smart chap has been helping me with it who ive mentioned earlier, design and tester for oem cooling systems.

Basically his view is, rad is worse design than the original (though should cool for around 100bhp in a frontal setup) and there is very low frontal pressure and flow through it which cant really be improved much. In its original setup this is fixed by having a mechanical fan forcing air to come through it and it only had half the hp requirements (37bhp in gordini trim). Same on the r8 and the Imp. Fuel goes in and 1/3rd of its energy leaves the exhaust, 1/3rd to the wheels and the last 1/3rd leaves out of the radiator. My 6v electric fan has about 0.107bhp of power if not less. A mechanical can be north of 5-7bhp worth of power when full pelt so its no where near capable to cool it when in motion.

My car once warmed up and in motion has the fan on constantly but doesn't have the oomph to cool it when the energy requirements increase ie when driving.

Next step will be the tried and tested front rad setup, ive seen a few mounted at an angle below the front boot space and some that chop the floor out to have it totally vertical. I guess ill take a look abit more once i sort the front to back pipe work. Im probably also going to swap out to 12v at the same time so i can run a decent oem rad fan off something at a scrap yard. It should really make sure it can cool properly rather than the pissy fan ive got now. Curved oem style fans are apparently loads more efficient also. All fun and games, you win some you loose some but it will be better for it in the long run.

Saving grace is it drives sooooooo much better than the original engine and box and can easily keep with most normal traffic at sub 60mph lol, The head still looks nice and straight. So engine just need a fresh gasket and its ready to go again.
 
Gasket turned up this morning so threw that on along with the rest of the top end. Before condemning the rear rad setup I'm going to switch out to 12v and run an oe fan with ducting/cowling to see if it helps/makes a difference. I'm also going to try and switch out the header tank setup to the style used on vw group engines, a feed and top up that flows to the bottom rad hose with a return from the top rad hose as high as I can get it to release any trapped air. I've actually found a few old pics of rear rad dauphines with an electric fan and engine swap so I dont want to ditch the idea without trying a few more things.

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Scrap yard raid this morning for a selection of hoses, a header tank that might work and a fan and I came away with a radiator too. It was a calsonic item who I've heard off from my early gran turismo days so should be a good brand? slightly smaller than the new rad I have but also a different style core. It has a take off for self bleeding too which will help with trapped air issues. I've also measured its water volume at just under 1600ml or 1.6 litres (200cc more than the original dauphine rad an 600 more than the new rad). Next job is to get it fitted up. The fan though smaller is a curved oem style fan so I'm hopeful itll do a better job than what I have. So to surmise I have a smaller rad and fan 🤷🏻‍♂️🤦🏻‍♂️ but hopefully a better rad and fan with more water volume.
 
All plumbed in in a fashion as I'm not going to mad with making it neat and tidy yet until its all proved itself. Ran it all up and it seems good at idle, i wired the new fan to a 12v battery and fair play it moves some serious air in comparison to the "6v" fan. I will try and get the radiator totally paneled off again this eve/weekend and maybe do a quick test with the rad fan running off an independent 12v car battery and see how it behaves. If it works well it can all stay in place and be tidied up if not i can look to moving everything up front.
 
In today's news, I'm 85% it works.

So i made some poorly fitting radiator cowling and very poorly rigged up the fan to a relay and a 12v car battery i borrowed off a friend. The fan shifts some decent air when running. So i bodged it all in, held the header tank in with cable ties and used some odd hose pipe for one of the hoses just to test it all and went for a drive. I did a short run then checked everything over and tested the temps, all good. Then a slightly longer run and did the same and all was still good. So i beat its head in for 6 miles, harder than i ever had down some B lanes whilst scaring myself at how badly it handles when driving it abit loony, high revs up hills and still it didn't boil over and the highest temp i managed to see was 90c on the radiator inlet. I didn't manage to get it into the red on the standard gauge though i can now see how vague the gauge is. Ive probably tested for about 15 miles today now but didn't want to chance taking it for a run on the motorway with all the bodges in place. Id even lost some of my cowling at some point too so air was going straight through a 2 inch gap right across the top of the radiator and theres plenty of gaps for it to escape from elsewhere so i can only improve on that too. All in all i think its a WIN. So just need to sort an alternator so i can rewire everything and properly sort the coolant hoses, cowling and brackets.

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Looks like a win that Adey
hope so, shit brand rad with a poor core design and poo fan vs an expensive/known brand with a nice core plus a fan that shifts some air seem to be working well. Very surprised tbh considering the scrap yard rad is smaller and thinner but holds more water. Obviously time will tell with a proper setup of everything but i was always driving gingerly previously and today was able to get on the pedal and really lean on the engine (it hasn't got much to give but i definitely made it give it all to me)
 
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Oh wow, it's so hot today so I havent completed as much as I wanted.

so this was the final testing lash up.

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Pulled it all out to make a start on measuring for hoses and brackets. When I took the rad from the scrap yard i took the support brackets too. So they were re bent to suit how I needed them to secure the radiator properly. I've moved the top over another 2 inches than I had it so I could mount it nicely and reduce the air space/gap above it. It also lowers the height slightly so the header tank is effectively higher than it a touch.

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That's as far as I've gotten today.
 
Again not much done. A new header tank ordered which should fit nicely. Popped over the Forge Motorsport for some hoses. 2 x 19mm caps to block off the heater outlets on the water pump and a length of ali to plumb in my top rad hose. I painted it black as all the different colours in there were starting to do my head in. I will at somepoint get the lower hose made completely in aluminium but it should do for getting the car up and running. A few voltage droppers are on the way from the finest chinese sweat shop which will allow me to run my original temperature gauge and fuel gauge. Still havent started on the radiator cowling so that will probably be my next job.

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Few more bits turned up today, I think the water system is now wrapped up bar testing it actually works..... New headertank with its bracket straightened out so it was suitable for how I wanted to mount it. Feed from tank plumbed in to the water pumps heater inlet port to give maximum vacuum under the header tank 🤷🏻‍♂️ fills up really easily and all fits nicely. Starting to look a little cramped back there now. Hopefully the ali sheet will be here this week so I can make the radiator cowling too and that's the bulk of the work done 👍🏻

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