What's the best radiator solution

[gerrym]

Just to add to John's comments re temperature drop across the radiator. The design target is a little hard to achieve in practise across all operating variables, hence many cooling system designs use a bypass thermostat style with blending of hot water (via bypass) and cold (via radiator) back into the pump and hence cylinder block. In particular, the Zetec installation into the Elan needs this treatment. The LTC seems to survive without such a design but then again, who knows bore wear and head gasket failure might be improved.

For what its worth, my Plus 2 has been fitted with a VW Golf radiator mounted in the nose. The X-sectional cooling area is about +30% compared to the narrow Stanpart radiator. The plastic/aluminium design won't suffer vibration and shock so needs a mount to minimise this.

Regards
Gerry

[alaric]

Hi all. Back from coffee.

When I wrote my post I had in mind the situation where you're sat in a traffic jam worried about overheating, with a system that includes a wax thermostat to control the flow rate. In that case, if you're starting to overheat, with the thermostat fully open, then making sure you have no constrictions in the flow elsewhere and a high enough flow rate will surely help (especially if the rad is small). Under normal operation I thought the time constant of the thermal oscillations in the system would be controlled by the thermostat acting as a damper by controlling the flow rate. As the flow rate is increased, the temperature profile in different parts of the block and head may become more extreme, but I would expect this to be tempered by the thermal properties of the metal vs the size of the water galleries, and it'll be a function of the temperature drop across the radiator, which will be lower if the flow rate is higher. Either way, a damped thermostat in the loop is surely essential for a normal road going car. A racing car's presumably a different matter. But this is all by the by really, as I'm actually limited by what's available on the market and budget.

So far I've gleaned that

The original set up is really only weakened by the poor electrical fan.
The wider Triumph based rad is adviseable for peace of mind.
The use of a header tank / replacement thermostat housing will improve the effectiveness of whatever rad is installed.
The water pump is fine as is.
There's no need to consider an oil cooler.
The heat from the interior heater is limited by the flow rate through the internal radiator.

So, a full width triumph based rad with either the swirl pot or the revised thermostat housing will be fine, with the choice based on cost and ease of installation.

All the best.

Sean.

[alaric]

Gerry, I like the idea of the VW golf rad mounted in the nose. I was only concerned that the nose overhangs the chassis, so and more weight up there is going to stress the bodywork. Presumably the foremost chassis mounting bolts can be used for fixing of brackets to take the weight. I'll take another look at the golf rads.

Using a secondary bypass thermostat is a bit like having a differential term in a PID loop isn't it - stops the system going into oscillation / reduces overshoot. All you need now is an integrator and you're done; that's where a CPU controlled pump would be useful I presume.

All the best.

Sean.

[GrUmPyBoDgEr]

"then making sure you have no constrictions in the flow elsewhere and a high enough flow rate will surely help (especially if the rad is small). Under normal operation I thought the time constant of the thermal oscillations in the system would be controlled by the thermostat acting as a damper by controlling the flow rate. As the flow rate is increased, the temperature profile in different parts of the block and head may become more extreme, but I would expect this to be tempered by the thermal properties of the metal vs the size of the water galleries, and it'll be a function of the temperature drop across the radiator, which will be lower if the flow rate is higher".
Yes
"Either way, a damped thermostat in the loop is surely essential for a normal road going car".
Yes

"So far I've gleaned that

The original set up is really only weakened by the poor electrical fan.
The wider Triumph based rad is adviseable for peace of mind.
The use of a header tank / replacement thermostat housing will improve the effectiveness of whatever rad is installed.
The water pump is fine as is.
There's no need to consider an oil cooler.
The heat from the interior heater is limited by the flow rate through the internal radiator.


So, a full width triumph based rad with either the swirl pot or the revised thermostat housing will be fine, with the choice based on cost and ease of installation".

Yes
"Using a secondary bypass thermostat is a bit like having a differential term in a PID loop isn't it - stops the system going into oscillation / reduces overshoot. All you need now is an integrator and you're done; that's where a CPU controlled pump would be useful I presume".

Yes

Have a good weekend
Cheers
John

[Frank Howard]

my Plus 2 has been fitted with a VW Golf radiator mounted in the nose.

Gerry,

I'm considering this conversion however I'll be installing it into a +0. Would you mind telling us the model year of the Golf that the radiator came from, the dimensions of the radiator, as well as the location of the inlet and outlet pipes? Also, would you confirm that the radiator comes without a filler neck? A photo or two would certainly be appreciated if that's possible. Thanks for your help.

[msd1107]

Look at

http://cgi.ebay.com/ebaymotors/ws/eBayI ... &viewitem=

This fits up in the nose. The only problem is that the inlet is on the right, but if you put it in the nose, you are going to have to get new hoses anyway.

Being up in the nose, there is better airflow through the radiator, rather than in the stock location.

David
1968 36/7988

[garyeanderson]

http://store.summitracing.com/partdetai ... toview=sku

This is a Griffin radiator sold by summit Racing, $280 may not be in your budget but the dimentions are given as 13 inches high by 22 inches wide. The feet on the outboard sides at the bottom need to be trimmed to fit down in the nose but it does fit with both vacuum canisters in place and is about the max that will. Many of the VW radiators are 26 inches wide so make sure of the size before you buy.

Gary

more info
elan-archive-f16/radiator-change-t9157.html
elan-archive-f16/scirocco-radiator-t11256.html

this one has photos
elan-f14/griffin-scirocco-radiator-install-t15346.html

[Jas]

I had problems with overheating last year, so over the winter I had the radiator recored with a modern 3 core element, fitted Clive boys thermostat housing and most important I think a 9? Pacet Profan and a 87?/82?C temperature switch.
The temperature is now 75?C on the open road and max 90?C in heavy traffic.

One thing though, I moved the expander bottle up to where the sprinkler bottle/sack is, but the coolant won?t go back into the thermostat housing when it cools down. I have checked for air leaks. It seems like there is more and more water going out of the system and into the expander bottle, until the top radiator hose is almost empty!
Anybody got any ideas?

[elansprint71]

Even with the Cliveyboy/Cosworth thermo housing, I think that the heater is still going to be the highest point in the system, a bleed valve in the heater hose is the only way to exclude ALL the air.

Cheers,
Pete.

TT 26/R ally rad, pre-Clivey thermo-housing, expansion tank and still getting air-locks.

[gerrym]

David, I'll dig out my records for the VW Golf Radiator. Pretty much any Golf Series II or III petrol 1.1, 1.3, 1.6 will do. In the UK these radiators sell for about ?40 new..

Hose sizes are 32mm. There's a 8mm air bleed connection, no header tanks. Both inlet and outlet are on the same side (one above the other). A remote filling system (Clivey Boy's ??) is needed. This also means no more bonnet damage from the cap.

For the Plus 2, because of the bonnet design (front flange), both hose connections need to be along the bottom for a nose installation. Alternatively forward facing and then hard piping/hoses to suit.

Nissens website has a catalogue with all the details, alternatively try http://www.radiatorsonline.co.uk/catalo ... VOLKSWAGEN

Regards

Gerry

[Carlos A]

This maybe not the best but is my solution. Engine runs cool all day (75-85)!

[gerrym]

David, re your post with the link to the ebay radiator, thats the same as I purchased from Nisens. It fits loads of VW applications so I can't imagine it going out of production.

For the Plus 2, of the two 32mm nozzles, the upper will foul the bonnet flange as it opens; it might be necesary to reverse the installation so that the nozzles face forward to the nose.

Regards

Gerry

[Carlos A]

Here is another pic. This is a Griffin radiator with a couple of really powerful fans!

[Carlos A]

Another pic or my "solution"

[alaric]

Just for the record I don't agree with John's response above - the no at the start should, in my opinion, be a yes, if it's referring to what I wrote before. Also, I don't like being shouted at, which is what is understood by the use of capitals in forums like this, even if it is followed up with a smiley face. I've stayed away from this thread to avoid continuing posting tennis, which is a shame as I really appreciate the support from this forum.

I have my new radiator now; the ebay one with filler neck left off and a 9" Kenlowe with screw in switch. I'll probably get a second Kenlowe to make it look smarter. I also got Cliveboy's thermostat housing and his K&N filter assembly. It's all looking very shiny. Of course the radiator doesn't fit my car - my car's fault not the rad. I'm getting used to things not fitting now. Seems a shame to take a dremel to the mounting brackets on the rad but there you go - the sides of the engine bay in my car are a tad thicker than they used to be, and I'd rather cut the metal than gouge out recesses in the bodywork.

Sean.