7 replies to this topic

[catch_me]

I have a build going on that is a 1978 pickup with a Specialist Components TwinCam supercharged road spec engine. I am working on figuring out all of the cooling systems, both placement and best components to use in combination with this engine. I plan on using 2 oil coolers, one for the rotrex, and one for the engine, which will likely be ducted from a headlight housing. (The other headlight will be the intake for the engine.) I also will have a custom front mount heat exchanger mounted in the front bumper feeding the cooling water for the Water-to-Air intercooler of the intake. I am still questioning how I should configure the radiator to best work for my setup. At this point I plan on using the MINIMania Aluminum side mount radiator https://www.minimani...e-Mount-Cooling , but am not sure what I should do for the cooling fan. Am I best off using only a mechanical fan off of the crank pulley? If so which fan? Am I best pairing an electric pulling fan with a mechanical fan, or using just a electric pulling fan into the wheel well without a mechanical fan? (I have plenty of skills in both fabrication (I'm a mechanical engineer) and also wiring, so I can make anything work good. I am just wondering what would be the best in my project from those who have tried the various cooling options. Thanks!

[Richie83]

I had just an electrical fan on mine and found I had to run it all the time. This pulled air from the wheel well. I now run a mechanical fan and have the electric fan hooked to a pro control gauge; I believe you can also run the fan from the ECU. I don’t run oil coolers so cannot comment on that, but am interested in what you find out (to be honest I don’t track my car so have never had an issue with the oil
Getting hot; almost the opposite).

Note: i am using a fletcher aluminium radiator.

Edited by Richie83, 01 September 2019 - 08:46 AM.

[DeadSquare]

Supercharging does produce quite a lot more heat, so better heat transfer is more important than saving weight, go for a Copper, not Aluminum, side mounted radiator.

 

Are you using the BMW K series TwinCam conversion ?  If so, retain the standard water pump and fan, but add an electric fan in the wing.

 

As you seem to be a "belt & braces" sort of guy, better to find that it never switches on, than have the engine over heat occasionally.

[catch_me]

Supercharging does produce quite a lot more heat, so better heat transfer is more important than saving weight, go for a Copper, not Aluminum, side mounted radiator.

Are you using the BMW K series TwinCam conversion ? If so, retain the standard water pump and fan, but add an electric fan in the wing.

As you seem to be a "belt & braces" sort of guy, better to find that it never switches on, than have the engine over heat occasionally.

A side mount aluminum radiator should still cool as good if not better than a copper radiator from a theoretical heat transfer perspective, as the fins in a copper radiator are soldered in with lead and other forms of metal, which greatly reduces the overall thermal efficiency of the radiator. Also, aluminum fins are longer, making an aluminum radiator restrict less airflow than a 4 row copper radiator.

It is a BMW K-series TwinCam, so that makes sense to keep the standard water pump and fan, and just add an auxiliary electric in the wing.

[GraemeC]

The engine bay is constantly flooded with force fed cold air you just need to direct that through the fins, either by pulling or pushing depending on which side you place your fan. The you need to get rid of that hotter air so exhaust it outside the engine bay, such as dumping it into the wheel well.

[Spider]

It's actually well documented that for heat transfer, copper radiators are better than aluminum types.

 

 

<Edit;- here's a table;-

 

Which Metals Conduct Heat The Best? Common metals ranked by thermal conductivity Rank Metal Thermal Conductivity [BTU/(hr·ft⋅°F)]

1 Copper 223

2 Aluminum 118

3 Brass 64

4 Steel 17

5 Bronze 15

 

https://www.metalsup...ct-heat-best/   >

Edited by Moke Spider, 01 September 2019 - 08:40 PM.

[catch_me]

It's actually well documented that for heat transfer, copper radiators are better than aluminum types.

 

 

<Edit;- here's a table;-

 

Which Metals Conduct Heat The Best? Common metals ranked by thermal conductivity Rank Metal Thermal Conductivity [BTU/(hr·ft⋅°F)]

1 Copper 223

2 Aluminum 118

3 Brass 64

4 Steel 17

5 Bronze 15

 

https://www.metalsup...ct-heat-best/   >

 

Yes, based off just the material properties of copper compared to aluminum, copper is a much better thermal conductor. The problem is that copper radiators are not in fact 100% copper, and the solders used to braze the fins to the copper tubing are a huge inhibitor of heat transfer (traditionally lead based solders are used which lead has a thermal conductivity of about 21 BTU/(hr·ft⋅°F)). I have actually tested copper versus aluminum heat exchangers for a heat transfer class, and they end up very comparable based on the exact same core dimensions and fin spacings. I do understand it all depends on the manufacturer of the radiators though. I have not made up my mind for sure between aluminum and copper, but was more curious about fan setup for pulling/pushing the air through the radiator.

[Spider]

 

It's actually well documented that for heat transfer, copper radiators are better than aluminum types.

 

 

<Edit;- here's a table;-

 

Which Metals Conduct Heat The Best? Common metals ranked by thermal conductivity Rank Metal Thermal Conductivity [BTU/(hr·ft⋅°F)]

1 Copper 223

2 Aluminum 118

3 Brass 64

4 Steel 17

5 Bronze 15

 

https://www.metalsup...ct-heat-best/   >

 

Yes, based off just the material properties of copper compared to aluminum, copper is a much better thermal conductor. The problem is that copper radiators are not in fact 100% copper, and the solders used to braze the fins to the copper tubing are a huge inhibitor of heat transfer (traditionally lead based solders are used which lead has a thermal conductivity of about 21 BTU/(hr·ft⋅°F)). I have actually tested copper versus aluminum heat exchangers for a heat transfer class, and they end up very comparable based on the exact same core dimensions and fin spacings. I do understand it all depends on the manufacturer of the radiators though. I have not made up my mind for sure between aluminum and copper, but was more curious about fan setup for pulling/pushing the air through the radiator.

 

 

When calculating the size of a Radiator for a given engine, there's a multiplication factor of 1.1 or 1.2 when using Aluminum over Copper.

 

Your heart is set on using Aluminum, so go for it.