Oil Cooler
Elite HDF Member
Joined: Sep 2006
Posts: 3,592
Likes: 6
From: Florida
Yes, they both radiate heat.
The "heat sink" style cooler has far more surface area to do so with and is made completely of aluminum, which is an excellent material for transferring heat. A typical 12" version has over 600 square inches of aluminum surface area to dissipate heat with. The usual oil cooler functions better than a heat sink style cooler at speed, but without fans the typical cooler does next to nothing at idle. A Harley engine was never designed to sit in traffic, but the cooling fins work great as long as you are moving....so much so that the diamond cutting guys are making a mint by just increasing the surface area of the fins by diamond cutting the edges.
Since I have no intentions of installing fans and the fact that I like the look, I'm going with the heat sink style cooler. They are also far more durable than a little tiny radiator.
The "heat sink" style cooler has far more surface area to do so with and is made completely of aluminum, which is an excellent material for transferring heat. A typical 12" version has over 600 square inches of aluminum surface area to dissipate heat with. The usual oil cooler functions better than a heat sink style cooler at speed, but without fans the typical cooler does next to nothing at idle. A Harley engine was never designed to sit in traffic, but the cooling fins work great as long as you are moving....so much so that the diamond cutting guys are making a mint by just increasing the surface area of the fins by diamond cutting the edges.
Since I have no intentions of installing fans and the fact that I like the look, I'm going with the heat sink style cooler. They are also far more durable than a little tiny radiator.
Road Master
Joined: Apr 2007
Posts: 848
Likes: 0
From: Lake Jackson, TX
Yes, they both radiate heat.
The "heat sink" style cooler has far more surface area to do so with and is made completely of aluminum, which is an excellent material for transferring heat. A typical 12" version has over 600 square inches of aluminum surface area to dissipate heat with. The usual oil cooler functions better than a heat sink style cooler at speed, but without fans the typical cooler does next to nothing at idle. A Harley engine was never designed to sit in traffic, but the cooling fins work great as long as you are moving....so much so that the diamond cutting guys are making a mint by just increasing the surface area of the fins by diamond cutting the edges.
Since I have no intentions of installing fans and the fact that I like the look, I'm going with the heat sink style cooler. They are also far more durable than a little tiny radiator.
The "heat sink" style cooler has far more surface area to do so with and is made completely of aluminum, which is an excellent material for transferring heat. A typical 12" version has over 600 square inches of aluminum surface area to dissipate heat with. The usual oil cooler functions better than a heat sink style cooler at speed, but without fans the typical cooler does next to nothing at idle. A Harley engine was never designed to sit in traffic, but the cooling fins work great as long as you are moving....so much so that the diamond cutting guys are making a mint by just increasing the surface area of the fins by diamond cutting the edges.
Since I have no intentions of installing fans and the fact that I like the look, I'm going with the heat sink style cooler. They are also far more durable than a little tiny radiator.
Elite HDF Member
Joined: Sep 2006
Posts: 3,592
Likes: 6
From: Florida
Yes, the oil is seperated by an aluminum plate so it must go 10" deep before it turns and comes back. The coolers of the same design with a fitting hole on each end do not have a seperator.
This type of cooler has been used in high performance automotive applications for a long time now.
They work very well in limited space applications due to the lack of direct airflow needed. Another interesting thing about them is the fact that they do not have much of a pressure drop through the cooler.
If you had a hot rod, especially with high compression or boost, you could use one of these to plumb your fuel through it and have it mounted inside an insulated ice box. This would allow you to run more timing without detonation and you would make more power.
P.S. Here's a few links to sites that advertise similar products:
https://www.polyperformance.com/shop...s-p-17217.html
http://www.buyautotruckaccessories.c...-sink-coolers/
http://www.derale.com/heat-sink-coolers.html
Another unique idea I've seen is plumbing your crash bar (if you have one) and flowing your oil through it. This will not be quite as efficient, but it will help cool the oil and will be virtually invisible.
This type of cooler has been used in high performance automotive applications for a long time now.
They work very well in limited space applications due to the lack of direct airflow needed. Another interesting thing about them is the fact that they do not have much of a pressure drop through the cooler.
If you had a hot rod, especially with high compression or boost, you could use one of these to plumb your fuel through it and have it mounted inside an insulated ice box. This would allow you to run more timing without detonation and you would make more power.
P.S. Here's a few links to sites that advertise similar products:
https://www.polyperformance.com/shop...s-p-17217.html
http://www.buyautotruckaccessories.c...-sink-coolers/
http://www.derale.com/heat-sink-coolers.html
Another unique idea I've seen is plumbing your crash bar (if you have one) and flowing your oil through it. This will not be quite as efficient, but it will help cool the oil and will be virtually invisible.
Last edited by mopardave; Jan 16, 2009 at 10:08 PM. Reason: P.S.
Elite HDF Member
Joined: Sep 2008
Posts: 4,440
Likes: 148
From: Northwest
Yes, they both radiate heat.
The "heat sink" style cooler has far more surface area to do so with and is made completely of aluminum, which is an excellent material for transferring heat. A typical 12" version has over 600 square inches of aluminum surface area to dissipate heat with. The usual oil cooler functions better than a heat sink style cooler at speed, but without fans the typical cooler does next to nothing at idle. A Harley engine was never designed to sit in traffic, but the cooling fins work great as long as you are moving....so much so that the diamond cutting guys are making a mint by just increasing the surface area of the fins by diamond cutting the edges.
Since I have no intentions of installing fans and the fact that I like the look, I'm going with the heat sink style cooler. They are also far more durable than a little tiny radiator.
The "heat sink" style cooler has far more surface area to do so with and is made completely of aluminum, which is an excellent material for transferring heat. A typical 12" version has over 600 square inches of aluminum surface area to dissipate heat with. The usual oil cooler functions better than a heat sink style cooler at speed, but without fans the typical cooler does next to nothing at idle. A Harley engine was never designed to sit in traffic, but the cooling fins work great as long as you are moving....so much so that the diamond cutting guys are making a mint by just increasing the surface area of the fins by diamond cutting the edges.
Since I have no intentions of installing fans and the fact that I like the look, I'm going with the heat sink style cooler. They are also far more durable than a little tiny radiator.
Once you get the heat of the oil out into the construction material, then you have fins to remove that heat into the air.
Both systems will dissipate heat, even with no airflow. It's called convection.
I would like to see some real world data from both systems: oil temp before install and oil temp after install.
By the way, anybody here try a Baker +1 oil pan on their bike?
Both types of coolers are made of aluminum by the way.
Last edited by archergodwin; Jan 16, 2009 at 10:20 PM.
Elite HDF Member
Joined: Sep 2006
Posts: 3,592
Likes: 6
From: Florida
I am aware of everthing you just said. The part where you are mistaken is how they work with a lack of air flow. A typical cooler relies on the air passing through it to cool the oil. That is why the oil has to make numerous passes through the cooler to transfer the heat to the thin cooling fins.
The heat sink style cooler is heated by the oil passing through it which is simultaneously cooled by dissipation or convection as you pointed out. The big difference being that the surface area on the conventional radiator style cooler is still surrounded by the oil that is supplying the heat. It only functions well with something removing that heat...that being the air passing through it.
The heat sink style cooler also benefits from an increase in air flow but also functions quite well at a stand still.
I will post my findings after I do my install.
For anyone else that wants to add an oil cooler and needs to buy the adapter to hook it up, get one for a small block chevy. Flex-a-lite's part number is 3961 and has 3/4"-16 threads and is 1.5" thick with a 2.5" o-ring seal area. Derale's part Number is 15730 and has a built in thermostatic valve. Please double check my numbers for yourself. I don't want to be held responsible for your mistakes! LOL
P.S. If you take a look at the typical radiator style oil cooler you will find that the cooling fins are thin but the tube that the oil passes through is round. They are not flat like a traditional car radiator. The traditional oil cooler relies on quick dissipation of heat from the thin cooling fins by using the air that passes through it to remove the heat while the heat sink uses lots of surface area to do it.
The heat sink style cooler is heated by the oil passing through it which is simultaneously cooled by dissipation or convection as you pointed out. The big difference being that the surface area on the conventional radiator style cooler is still surrounded by the oil that is supplying the heat. It only functions well with something removing that heat...that being the air passing through it.
The heat sink style cooler also benefits from an increase in air flow but also functions quite well at a stand still.
I will post my findings after I do my install.
For anyone else that wants to add an oil cooler and needs to buy the adapter to hook it up, get one for a small block chevy. Flex-a-lite's part number is 3961 and has 3/4"-16 threads and is 1.5" thick with a 2.5" o-ring seal area. Derale's part Number is 15730 and has a built in thermostatic valve. Please double check my numbers for yourself. I don't want to be held responsible for your mistakes! LOL
P.S. If you take a look at the typical radiator style oil cooler you will find that the cooling fins are thin but the tube that the oil passes through is round. They are not flat like a traditional car radiator. The traditional oil cooler relies on quick dissipation of heat from the thin cooling fins by using the air that passes through it to remove the heat while the heat sink uses lots of surface area to do it.
Last edited by mopardave; Jan 16, 2009 at 11:17 PM. Reason: P.S.
Elite HDF Member
Joined: Sep 2008
Posts: 4,440
Likes: 148
From: Northwest
I would like to see your results after the install Dave, really... I'm curious. I also want to verify that the 'heat sink' style of cooler you refer to is like the Milwaukee Twins dual cool?
Elite HDF Member
Joined: Sep 2006
Posts: 3,592
Likes: 6
From: Florida
It is similar. The dual cool uses fins that are either cast into or machined out of a tube. They don't have as much surface area as the one I am going to use but they do have a lower fluid to surface area ratio, so they should work well.
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