Well since my near over heating experience while driving back from detling on a warm day doing 70mph on a motorway, I am going to get a new rad and mount it on the side of the engine bay. Since changing my exhaust I am no longer able to scoop cool air from under the fug, and all hot air from the engine is hitting the rad, it currently works quite ok around town and country lanes, but not on a hard motorway run........so time for Mk2!!!

my current rad measures about 54cm x 37cm x 2.5cm total core volume = 5000cc.

I had another measure up last night of the LH chassis rail next to the engine and I have a max length of 60 cm in order to fit the new rad, so I have managed to find a rad from a Mk1 golf 1.5/1.6.......core size is 48cm x 32cm x 3.4cm = 5222cc.......so about the same volume as the other.....I think total length including the end tanks will be about 58cm, so will fit a treat under the 60cm side rail.....coincidentally its actually a bigger core than that used on the 130bhp 16V golfs........but the main gain is the core thickness, its about 27% thicker than my current rad (25mm versus 34mm), so I'm gonna stick with my two 9" fans as they will now be much more effective.

Here is a pic of the rad on ebay, its a double pass U-flow jobbie so will plumb in real nice in the fug.

http://cgi.ebay.co.uk/Radiator-VW-Golf-Sci...A1%7C240%3A1318

once installed I will run it on the fans only for a while - then see if I need to build in a ram-air duct.

i think the f33 ran two of those rads..one each side. mine still has the mounting straps fitted. just remember that uva couldn't stop the f33 overheating!!!

interesting!......probably over heated as the rads were not forward facing and were not ducted, the air probably just skimmed over the front surface, I'd be surprised if any air got pushed through the core........Alan Arnold was not the sharpest engineer I must say.

I just did a handy little calculation in order to compare a 9” pacet electric fan with a single 105mm (drain pipe ID opening) travelling at 70 mph………a 9” pacet fan will move 858cfm of air……..the drain pipe only manages 574cfm at 70 mph………which implies two 9” fans should be better than two 105mm drain-pipe ducts by 33%……..it looks like I would need 3 or 4 drain pipes in order to better the flow of the two 9” fans, which I’m just not going to do……..in which case I will stick with the two 9” fans only for now, as I think the thicker core will be the main gain for me - old 25mm, new 34mm.

i had overheating on the beach until i had a rad made up and mounted it right in the nose section. it was two metro cores thick if i remember. as you say, it is surface area that counts. i remember running mine with no rads and just connected to a oil drum filled with water. i thought it would take hours to warm up, but it was only about 30 mins!! just enough time to balance my quad su's...lol

hey that sounds real interesting.........can you please show me a pic of the rad installed, with and without bonnet fitted ideally........I must admit I have been shying away from doing that as I dont want long heavy pipe runs, but its still an option.......what are your core dimensions??? (L/W/H)

I do struggle to understand why this is a problem, would it not be an option to have a rad made to exactly what's needed, the core size can be larger than a standard that way. Diesels will often have a larger core as standard, which must be an option.
Personally I'd just put the rad where I have mine, I realise it's not everyone's choice, but apart from me liking it, it will cool in every environment from main road to traffic jam and cost me £50 brand new plus about £20 for the fans and shroud.
You can in quite extreme cases run a duct with a fan either side of the rad to actually force the air through it.
It's amazing how quickly it can heat a massive volume of water, and how a rad really can work so much more efficiently dispite it's size.
Getting back to what was first said, even if the air is coming hot off the engine, it would still be cooler than the engine. Really would have thought fans would have kept the temp down. Is an air-lock somewhere a possibility?

no pictures of car with rad fitted, but i still have rad in workshop. will take some pictures sunday for you. i know it was very thick and heavy. all my internal pipework was copper from the local plumb centre. that helped to keep it cooler. i also used water wetter from demon tweaks. seemed much better when i used it. pictures of car are here:
http://www.facebook.com/album.php?aid=1035...36&l=ff06d5e47b
this is what it looks like now. lots of work to do if i want it on the road for summer!!

Hi Bob - I cant put my rad up behind my head as I'm running a full windscreen and it still wouldnt get blasted with air.......I have now bought a Mk1 Golf GTI rad from ebay for £10 new!!!.......the double fan duct I previously made only cooled about 3000cc volume of core, in hindsight this is not enough........this new rad will be fully ducted into the fans and will have 5000cc (nearly double) of core being fan cooled.......no air locks - I fully de-gassed it........I also think where I used a secondhand rad from a 15 year old car, it was probably furred up inside - in hindisght that too was not the best starting point........I would like the rad as hidden away as possible, so I'm gonna forge ahead with the side mount option as it will look neat and compact.........I'm wary of having a custom made rad, as my fug just isnt worth it........If I thought it really needed it, I would........going to collect the rad tonight, get a duct made this week, then probably plumb it in this weekend........I'll keep you all posted :ph43r:

We'll all be checking for the photos!

Steve :D

Kinghty, I think you're a bit far away from me for this to be practical, but a friend of mine can fabricate pretty much anything from a drawing, if you think I can help let me know and I'll do my best.

no worries mate - I work in a prototype hybrid engineering environment, so have full workshop facilities at my disposal........they love a good "homer" when they are not busy with normal work!!!.....

anyways, the new Mk1 1.6 Golf GTI radiator arrived last friday and it is actually a copper core item.........I know pretty much all modern radiators are now aluminium cored........which got me thinking......whats more preferable, copper or ali???........so I googled about and sure enough the thermal conductivity of copper is about double that of aluminium........so my new copper rad will also help heat rejection.

I think (TBC!!) the reason manufacturers have gone to ali, is its cheaper and stronger so can resist higher operating pressures.

upon further inspection the coolant cores are ali, the fins are copper....weird!!!

anyway, in a moment of boredom and complete sadness I must say………I was wondering how much engine power that my two 9” electric fans draw…….they are both rated at 8.9Amps, in a 12v system that equates to 0.214Kw power draw on the electrical system for both……..an alternator is 70-80% efficient at converting mechanical power into electrical energy………say using 70%, therefore pro-rata’d back to 100% = 0.306Kw mechanical power on the crankshaft…….or about 0.4hp……..sounds piffling me thinks……..also considering aerodynamic drag increases with at the square of speed, it should be very efficient compared to a huge rad duct on the front of the car.

Heres a pic of my new rad, the boys at work are now making a new duct from 3mm black poly-prop, so both fans will be pulling air through the entire rad core, and I have a machine shop who is making some rear mudguard supports, as the current ones are in the way of the new radiator installation………not to mention I’m installing a new kitchen too!

core dimensions are 48cm x 31cm x 3.1cm thick

Well, after all my bits have been made, this weekend I took the plunge and installed the lot.......started friday, finished sunday morning....phew!!!.......here are the results for you all to see.......I'm quite pleased it looks quite snug and well packaged, the copper pipes are 28mm items, and will soon be painted matt-black in order to dull them back a bit, as it does look like it needs corgi approval otherwise!!!

I took it out for a ride on quite a hot summers day and it didnt get over 90Degc......I have just ordered some red-line water wetter to also help with the summer temps.

cool (no pun intended ) looks really neat! good job :D

Nicely done Knighty, it looks a lot subtler than I thought it would.

Interesting reading these posts as I had an Alfasud engined Fug once and now my V8 has just come back.
I had lots of problems knowing where to best mount the rad for the Alfa engine. It ended up across back of engine but offset to one side with scoop to trap cool air coming around one side of car between rear wheel and engine. It worked OK but didn't look very good.

The V8 has a rad across behind the seats. It is low and wide and is from an old Austin Princess, recored with two BL fans on it. I am told a montego radiator is similar (export version is best I am told as has 3 cores for hot countries). With a full depth windscreen the fans were on most of the time. With a shallow wind deflector it works better - better airflow. In fact one time it was driven from Stoneleigh show to Yorkshire by previous owner with a failed alternator - wind deflector taken off and fans disabled to save battery for sidelights (it was dark) and ignition. The ram effect was enough to keep engine cool (very windy for driver though).

Since then I took the two small bore tubes from engine that are meant to supply the heater matrix and ran them to front of the car. At front of car projecting just slightly below lower edge of bonnet panel, at sloping angle so it acts like an air scoop, is the heater matrix from an old Fiat Panda (small but deep). This acts as a sort of auxiliary radiator assist device. I am also told something like a transit van matrix would be good as again these are thicker than car ones.

Amazingly this tiny heater matrix, because so much cool air gets rammed through it, will reduce the amount of time the main radiator fans are on by over 50%. It is just an idea as is quite easy to do, easier than putting entire main rad in front of car, just used copper plumbing pipe about 1.5cm diameter. Also helps keep your feet above zero in cold weather. Matrix wrapped in mesh to stop stones.

Best wishes

John

i had a small "thick" metro rad in the front of mine...and all copper tubes where possible (painted black)..i can understand how the road version overheated all the time..thinking about a smaller turbo engine now...just got to find another gearbox so i can see what i could fit...saab turbo is the cheapest option..but might have to be rover based..200bhp should be fine for what i want to do.

Hi John - nice to finally meet you!......funny you should mention the heater matrix addition, I had started to consider that one towards the end of summer, but after changing the thermostat, the temperature remained much more stable......turns out my old stat was sticking open, hence the coolant temp would shoot up once on a motorway. everything now works ok and it pretty reliable.......fingers crossed!