HE Fans

Riptide

Well-Known Member
Established Member
Joined
Dec 23, 2009
Messages
1,639
Location
Sparks, NV
I read DOB's article on the HE fans and am considering removing them.

Has anyone actually done testing before and after under similar ambient air and driving conditions to determine the effect? I mean in a real supercharged car and not sticking the HE on top of a truck.

Just bought a set of replacement spal fans now and am wondering if I threw $200 in the toilet.
 

Riptide

Well-Known Member
Established Member
Joined
Dec 23, 2009
Messages
1,639
Location
Sparks, NV
If and when you do. Keep track please of your ambient temps and IAT values. Ideally, would be good to know IAT for:
3 minutes of idle.
40mph.
WOT.
All of this after the car has been run up to operating temp. Say driven for 20 minutes. And values before and after the fans came out. TIA
 

vortecd

Well-Known Member
Established Member
Joined
Aug 16, 2012
Messages
1,525
Location
MI
My thoughts on fans probably don't do much good if you never have to stop. In traffic and stop and go is why I had them on my Mustang.

I also had a fan on my transmission cooler on my '87 Mustang since not much air is flowing through there when you are stopped
 

Riptide

Well-Known Member
Established Member
Joined
Dec 23, 2009
Messages
1,639
Location
Sparks, NV
For a dedicated road course car it's a no-brainer. For a street car/drag strip car it becomes more debatable.
 

Stangra

Active Member
Established Member
Joined
Sep 21, 2018
Messages
272
Location
CA
My thoughts on fans probably don't do much good if you never have to stop. In traffic and stop and go is why I had them on my Mustang.

I also had a fan on my transmission cooler on my '87 Mustang since not much air is flowing through there when you are stopped

Keep track please of your ambient temps and IAT values. Ideally, would be good to know IAT for:
3 minutes of idle.
40mph.
WOT.
All of this after the car has been run up to operating temp. Say driven for 20 minutes. And values before and after the fans came out. TIA

If I'm not mistaken at idle/very low throttle there is no boost, bypass valve is open so not much heat being generated or need for fans

For a dedicated road course car it's a no-brainer. For a street car/drag strip car it becomes more debatable.
Unless you're doing WOT pulls followed by driving very slowly or stopped, like at a drag strip, fans just restrict the natural speed/volume of air through a heat exchanger.
 

SHIFTYBUSINESS

Well-Known Member
Established Member
Joined
Jun 14, 2013
Messages
1,318
Location
Texas
If and when you do. Keep track please of your ambient temps and IAT values. Ideally, would be good to know IAT for:
3 minutes of idle.
40mph.
WOT.
All of this after the car has been run up to operating temp. Say driven for 20 minutes. And values before and after the fans came out. TIA
I'm planning on doing before and after iat temps to see the difference. Right now I'm daily driving the mustang so its probably going to be a few weeks.

Sent from my SM-G935V using the svtperformance.com mobile app
 

Riptide

Well-Known Member
Established Member
Joined
Dec 23, 2009
Messages
1,639
Location
Sparks, NV
If I'm not mistaken at idle/very low throttle there is no boost, bypass valve is open so not much heat being generated or need for fans
Can't argue that the practical need for fans while the car is idling at least on the street is minimal however IATs definitely climb at stop lights. Fans or no fans.

I'm planning on doing before and after iat temps to see the difference. Right now I'm daily driving the mustang so its probably going to be a few weeks.
Hey that's great! I won't be doing this project until probably July sometime. Depending on your results, I may pull my fans, and when I do will also try to reproduce this experiment with data before and after controlled for variables as well as I can.
 

Riptide

Well-Known Member
Established Member
Joined
Dec 23, 2009
Messages
1,639
Location
Sparks, NV
Correct, IAT2 is the important value. Just to throw some data out there, after I've driven the car for 20 minutes I'm seeing 129-132 IAT2 values while idling for 3+ minutes at a light on an 82 degree day. After the car gets moving up to about 40mph they fall back to around 125.

Pulling the fans in theory should result in higher temps while idling (guessing 136-140) and cooler (120-122) while cruising under same conditions.
 

Stangra

Active Member
Established Member
Joined
Sep 21, 2018
Messages
272
Location
CA
I'm seeing 129-132 IAT2 values while idling for 3+ minutes at a light on an 82 degree day. After the car gets moving up to about 40mph they fall back to around 125.
50° above ambient temp at idle seems high, 42° above ambient @40mph seems high too. Are you getting enough coolant flow through the H/E? What pump are you using?
 

Riptide

Well-Known Member
Established Member
Joined
Dec 23, 2009
Messages
1,639
Location
Sparks, NV
The same bosch pump the kit came with in 2014. If there is a problem with the fluid flow I can't tell. Looks fine to me. Tried numerous times squeezing lines to make sure there was no air in there. If there is, I've never been able to get it out.
 

Stangra

Active Member
Established Member
Joined
Sep 21, 2018
Messages
272
Location
CA
The same bosch pump the kit came with in 2014. If there is a problem with the fluid flow I can't tell. Looks fine to me. Tried numerous times squeezing lines to make sure there was no air in there. If there is, I've never been able to get it out.

I've been using the Pierburg CWA50 pump (2013+ GT500 pump), significantly more flow than the Bosch pump. Great info from DOB here:

http://departmentofboost.com/PDF/13' GT500 Pump - Intercooler Install Instructions 10-14' S197.pdf

http://departmentofboost.com/PDF/13_GT500_Pump-Remsen De-Gas_Mod _nstructions.pdf
 

Riptide

Well-Known Member
Established Member
Joined
Dec 23, 2009
Messages
1,639
Location
Sparks, NV
VMP also sells the 13+ GT500 pump and I'm considering it. Will take some bracket fab work to get it to fit where the bosch was located but everything should fit right in. I wasn't aware you needed to mod the hose at the degas tank? That looks so weird. It's like the inlet and outlet are connected with a section of hose by those two T junctions. Doesn't make any sense to me.
 

Stangra

Active Member
Established Member
Joined
Sep 21, 2018
Messages
272
Location
CA
I wasn't aware you needed to mod the hose at the degas tank? That looks so weird. It's like the inlet and outlet are connected with a section of hose by those two T junctions. Doesn't make any sense to me.
I think the point is to allow a significant amount of the coolant flow to bypass the degas, otherwise there's so much turbulence in the tank the pump can ingest aerated coolant and cavatate.
 

Handlebar Moustache

Well-Known Member
Established Member
Joined
Jul 29, 2017
Messages
577
Location
Louisiana
Interesting topic; subscribing. DOB's page is interesting and in direct contradiction to info from vendors of dual-fan HE products. I'm interested in hearing about your results. Has anyone seen/used the DOB Titanic Heat Exchanger? I think it's a prototype now, but Etter has made at least one batch of them and is in the process of making the 2nd batch.
 

cidsamuth

Liberty Biberty
Established Member
Joined
Aug 16, 2010
Messages
906
Location
Virginia
IMO, I think it violates logic to say the fans, when running, make temps higher than with no fans at all. Worst case, I could see how it can be argued they don't have ENOUGH OF a real world benefit, especially in consideration to the expense, install time, and electrical juice they suck up.

From what I saw anecdotally, where the fans make their money is right off idle. When idling, you don't see much benefit from any blower cooling system no matter how good, as there is so little air being passed over the intercooler. Your cooling system could be the best designed thing in the world, and it is not going to matter very much.

But, in theory, while you are idling and the IATs are climbing because of that lack of air, the fans are keeping the fluid running through the heat exchanger much cooler than it otherwise would be. So, when you open up the throttle, the IATs are going to DROP FASTER than they would have without fans.

Obviously, a better pump would also have them effect. Using both a VMP dual fan HE and the GT500 pump made a very big impact for me on my street car. I didn't try to do exact comparisons under the exact same conditions. I just know that the temps never climb as high as they used to when I'm buzzing around town. And, when I have to sit and idle for long periods of time, they drop very fast after I get back on the throttle.
 
Last edited:

Handlebar Moustache

Well-Known Member
Established Member
Joined
Jul 29, 2017
Messages
577
Location
Louisiana
IMO, I think it violates logic to say the fans, when running, make temps higher than with no fans at all. Worst case, I could see how it can be argued they don't have ENOUGH OF a real world benefit, especially in consideration to the expense, install time, and electrical juice they suck up.

From what I saw anecdotally, where the fans make their money is right off idle. When idling, you don't see much benefit from any blower cooling system no matter how good, as there is so little air being passed over the intercooler. Your cooling system could be the best designed thing in the world, and it is not going to matter very much.

But, in theory, while you are idling and the IATs are climbing because of that lack of air, the fans are keeping the fluid running through the heat exchanger much cooler than it otherwise would be. So, when you open up the throttle, the IATs are going to DROP FASTER than they would have without fans.

Obviously, a better pump would also have them effect. Using both a VMP dual fan HE and the GT500 pump made a very big impact for me on my street car. I didn't try to do exact comparisons under the exact same conditions. I just know that the temps never climb as high as they used to when I'm buzzing around town. And, when I have to sit and idle for long periods of time, they drop very fast after I get back on the throttle.

Did you check out DOB’s page? His testing suggests a max benefit of ~3 degrees cooler IAT2 temps from fans at idle, and at speed, the fans do impede airflow. Your cooler temps (post-VMP install) are likely a result of the more robust design of the heat exchanger and pump... not the fans. Nobody has produced testing results (that I have seen) that show significant benefits from having fans. I’d buy a fanned unit if someone had some data to say it actually is worth the expense.
 

Users who are viewing this thread



Top