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Mostin
03-04-2011, 01:53 PM
Hello all.

As im looking at putting in a water cooled engine (im looking at going down the Subaru line) Where have you mounted your rads & how well has it worked?

Pics would be nice :cheers:

Thanks.
Mostin

CyCo
03-04-2011, 02:53 PM
Well, I'm sure you've seen my setup, but not what I'm planing.

I'm thinking of a subframe up front, to hold duel radiators in front of the wheels. They'll have to be small, but that can be part-way corrected by thickness and quality. They'll be getting fresh air in from straight under the nose, and dumping hot air under the car. The subframe will also help support the nose, and also the front end of the plumbing, which I'll leave as the 1 & 1/4" copper pipe. They'll probably also have some thermo fans fitted for times when I'm stuck in traffic or it's just a damn hot day.

This way I'll be able to get 'some' storage space back by glassing in a new under bonnet area.

islandman
03-04-2011, 03:39 PM
Front mounted in the nose

http://i713.photobucket.com/albums/ww131/islandmanhere/NovaRad.jpg

Air ducted in via a modified front end

http://i713.photobucket.com/albums/ww131/islandmanhere/IMG_5433-1.jpg

JemP
03-04-2011, 04:44 PM
Rear mounted on the Avante, the front mounted system was impossible to fill and bleed, as there are no opening panels at the front of a standard Avante. I've got it mounted to the side so air should go in through the top little vent when travelling. I've cut out under the wheel arch too, so that the moving wheel might just push a little more air in there (Mini style). If it doesnt work in practice when I'm on the road, i'll look to switch back to front mounted as I have cut out a nice big bonnet at the front now.

jimcub
03-04-2011, 10:49 PM
talk to Dirk who has a subaru in his if he still has it.

Spacenut
04-04-2011, 12:54 PM
I'm thinking of a subframe up front, to hold dual radiators in front of the wheels

...Which is exactly what the Porsche 996 (or whatever the watercooled Porkers call themselves these days) uses. This would have been my preferred solution as well, if I had retained the rear engine arrangement in my car. Air locks and venting would have to be considered, but with a header tank at the back (needs to be the highest point in the system) and suitable air bleed screws on/near the rads(maybe accessible with the headlamps removed?), it should work fine.

As Jimcub says, Dirk has a Legacy 2.2 engine in his Nova, with the radiator in the nose. He recently modified his bonnet "nostrils" to face backwards, which act as air extractors for the radiator, improving cooling. Of course, you have a Mk2 Nova so you probably don't have nostrils, but that shouldn't stop you considering air extractor vents if you opt for a single, centrally mounted radiator in the front.

The advantage of the dual radiators in front of the wheels is that you can exhaust the hot air into the wheel arches, and if you can place (or use a Mk1 undertray) air intakes either side of the number plate to get direct airflow through them. There's just enough room for slimline pusher fans in front of the rads, but best of all the front compartment space is left largely intact, so you can choose between optimum weight distribution (leave the spare wheel and battery in place) or convenience, and turn it all over to luggage :D

Lauren

Peter
05-04-2011, 12:14 AM
biggest problem on the rear engined Skodas and very early Renaults was the front mounted rad, learn and beware, I brewed up a couple of Skodas. I would go for a pair of old Mini rads mounted just foward of the rear axles.

islandman
05-04-2011, 03:40 AM
One of my early attempts had three radiators, one at the rear and two mini rads either side in the arches ahead of the axles at Peter suggested. I found that for normal running it was ok, but when the engine was pushed hard there just wasn't enough airflow to keep it sufficiently cool (even with fans)

Big Birds Car
05-04-2011, 08:05 AM
but when the engine was pushed hard there just wasn't enough airflow to keep it sufficiently cool (even with fans)

Bu66er!! I can't say if it works or not as yet but I have piggybacked two rads on the off side of the car just inside the engine bay, with a fan, I have also added vents into the rear panel to aid getting the hot air out. If it doesn't work I'm in a bit of trouble as I still want the front area for spare wheel etc. and I've done with adding things in the side pods (well I had when I last looked at it :violin: ).
Mind you by the time I get to work on it again the rads will have probably rotted anyway :laugh:
Rads up front are not a major job really, getting the right water flow is what you need, I run an MGF which has the rad up front with two 1" pipes that run under the car for feed and return water and I also run another kit car that has the rad up front again with something like 1" pipes (again under the car). Neither of these cars have had over heating issues, except when the F's head gasket went.

Spacenut
05-04-2011, 12:18 PM
You can get pretty much any configuration to work, provided that you put in some design effort. Look at the original Lamborghini Countach prototype - twin radiators mounted longitudinally each side of the engine bay - to cool a 5-litre V12! It apparently was fine at racing speeds, but boiled-over in traffic. Hence the airboxes and NACA ducts on later versions (not forgetting the extractor vents on the rear wing tops). Ferrari Testarossa and 348 had radiators on the flanks, ahead of the rear wheels and dumping into the rear wheel arches. Works fine. McLaren F1 - twin radiators behind the front wheels, exiting along the flanks. Perhaps the most outrageous configuration was used by the Murcielago (which it inherited from the Diablo), which is twin radiators behind the rear wheels, with intakes on the wing tops and extractor vents on the rear panel. With the last-of-the-line Bizzarrini V12 displacing 6.2 litres and pushing out 600-plus bhp, with no apparent cooling issues, I would say that there is a solution for just about any radiator configuration you could think of.

Closer to home, Martin's Reek is another prime example - radiator buried behind the rear bulkhead and cooling a 2.5 litre V6. Get the airflow right, and even the most unlikely set up can work!

Lauren

CyCo
05-04-2011, 02:14 PM
Don't forget there's a reek here in Oz running a 2.2 Subaru Liberty with the radiator at the very rear of the car, with no overheating problems (Kyms old one).

Peter
05-04-2011, 06:15 PM
Spare wheel? these days, pleeeease
Puncture plug kit and a mini compressor and maybe a can of foam, many modern cars don't even come with a spare wheel anymore and my SS hasn't had one ever.

Big Birds Car
05-04-2011, 07:15 PM
Spare wheel? these days, pleeeease
Puncture plug kit and a mini compressor and maybe a can of foam, many modern cars don't even come with a spare wheel anymore and my SS hasn't had one ever.

You harp on about this everytime I mention a spare. When you get to use your SS a bit more and you have a split tyre rather than just a puncture then see how your puncture plugging, foam and mini compressor deal with it. (like to see you finding the puncture at two in the morning in the pi55ing rain at the side of the M1 motorway).

I also wouldn't say many, more like some, cars don't come with spare wheels, however the majority that I know of do have something even if it is a skinny space saver one.

I prefer to have a means of getting home if it is available, I do a far amount of driving a year and see many people at the side of the road waiting for a recovery truck or the AA to come and sort out their flat tyre, either the foam doesn't work, the tyre has split from the bead or they don't even know how to change a tyre.

I do have a car without a spare but that is because the tyres are too big and there is nowhere to have a spare but where I can then I will.

Spacenut
05-04-2011, 07:29 PM
Plus the front brakes lock up and you crash into things if there is no weight over the front axle. Ask me how I know :blushing:

JemP
06-04-2011, 08:35 AM
Agreed, I've had two punctures whilst driving, and neither time would a tin of foam or a puncture plug have done anything. Both times it was a case of jacking up and putting on the spare. I had a tyre slashed at a motorway services near Cardiff and would never have got to the millenium stadium, or back home afterwards, without my trusty space saver. and Lauren is right, a bit of weght over the front axle comes in handy, so my spare will be mounted on the spare wheel bracket that Avante Cars handily built into the chassis frame :)
It was one of the reasons I plumped for a rear rad too, that and the fact that my one and only road drive in the Avante was curtailed by an overheating problem with the front mount rad, but I'm sure that was down to air in the system.

bushboy
06-04-2011, 08:44 PM
I have a MR6

Thats a Mid Radiator 6 cylinder

http://i6.photobucket.com/albums/y231/bushboy554/Rollbarseatbeltmounts.jpg

this is where the rad is sitting. The body, if you can work it out, is hanging above it in this picture.


http://i6.photobucket.com/albums/y231/bushboy554/rollbar003.jpg
a shot from behind


http://i6.photobucket.com/albums/y231/bushboy554/radiator002.jpg

http://i6.photobucket.com/albums/y231/bushboy554/radiator004.jpg

http://i6.photobucket.com/albums/y231/bushboy554/radiator008.jpg


When it had a subaru in it I was going to use this set up

http://i6.photobucket.com/albums/y231/bushboy554/rearrad2.jpg
http://i6.photobucket.com/albums/y231/bushboy554/rearrad1.jpg

That is what these large side vents were originally for
http://i6.photobucket.com/albums/y231/bushboy554/rearrad3.jpg

When I later stuck the V6 in I didn't want to fill them in, wanted to move some weight forward of the rear axle and so stuck with them and used the mid mount rad.

The first few runs had the engine over heating. The thermo fans didn't turn on so the switch was by passed & the twin two speed fans are now operated by toggle switches. When the temp gauge reads 90 I turn the small one on slow. With spirited driving the temp gauge occasionally reads over 100 but I know that it is not reading correctly as I put a small battery powered digital temp gauge in the system to monitor it. before it gave up the ghost it never went above 98. (Celsius to all you farenhighters)

Bushboy

Dirk
07-04-2011, 08:17 PM
I’m still around its just that BT has still not been able to sort my land line after 6 weeks! So the only internet access I have is with a mobile 56k GPRS modem. I’m sure that carrier pigeon would be quicker than my E-mail at the moment.

Anyway back to the question when I first fitted the Scooby engine I had 2 metro radiators either side of the engine, the main reason for putting them there was because of the water inlet and outlet facing the rear of the car, all of the plumbing and the radiators made the engine bay packed and untidy although I never had a problem with over heating or bleeding the system.

The set up I have now is one metro radiator in the front and the reversed water inlet and reversed thermostat housing it is much neater, the inlet and outlet for the engine both now face the front of the car on the same side of the engine much easier. have a look at the RJES web site for these mods.

I’m not going to upload any photos at the moment but if you have a look at the “Your Cars Section” of the forum I think I have uploaded them all before.

Dirk

islandman
08-04-2011, 04:07 PM
I was at a local garage today seeing the progress on my new classic acquisition undergoing some small jobs. They had a couple of Fezza's up on their car ramps so I spent some time snooping around for a closer look at the underneath which is something you don't get to see in all the marketing material and adverts.

I was quite surprised to see they are not so special and looked quite basic up close, whilst they were extremely flat for ground effect they were not particularly smooth with all manner of bolts sticking out just waiting for the nearest speed bump to round them off making it impossible for the bolts to be removed by normal means.

Anyway, to the point of my post....both cars had radiators diagonally mounted in each front wing ( being diagonal allowed them to have larger rads and more surface area). Both had fans mounted to the back of each rad and what seemed to me to very small vents at the sides to allow hot air to escape. So I guess event with big engines and horsepower it can bee cooled by a lot less than you thing if you get the air movement right and avoid air locks.

Mostin
14-04-2011, 10:25 AM
Hi all.

Thanks for your input it all helps.

Dirk:- When you get your Broadband sorted could you post or even email me some pic's as it would be a great help.

Thanks.
Mostin.

Dirk
14-04-2011, 01:08 PM
Mostin,

Will do but I'm not expecting the line to be sorted untill early May.

Dirk