Sponsored

Whipple dual fans or oversize heat exchanger?

HoustonGT

Well-Known Member
Joined
Aug 8, 2015
Threads
71
Messages
330
Reaction score
86
Location
Danville, CA
Vehicle(s)
2020 GT PP2
About ot pull the trigger on a whipple stage 2 kit. Currently in the bay area in CA but could be movng back to Houston in the future. What do you all recommend for extra cooling in either/both climates? thanks!
Sponsored

 

engineermike

Well-Known Member
Joined
Jul 15, 2018
Threads
16
Messages
4,119
Reaction score
3,483
Location
La
Vehicle(s)
2018 GTPP A10
I’ve been trying to figure this out myself. Lots of opinions and hearsay and very little actual data. I have neither the oversized exchanger nor fans but I do have log data where you can follow the MCT and IAT trends over the course of a drive. I really wish someone with the fans or upgraded exchanger had that same data we could compare. MCT is like fuel economy - very dependent on driving context so hard to compare without an entire data set.
 

Bluelightning

Bluelightning
Joined
May 22, 2018
Threads
0
Messages
1,013
Reaction score
687
Location
North of Houston, TX
Vehicle(s)
Lightning Blue 2017 GT350, 2019 F-150 4x4 Ecoboost (Daily)
Vehicle Showcase
1
Get the oversized heat exchanger. I did the fans on my 18, but if I did it again I would do the oversized. You probably won't be sitting in traffic as much as you thought, and as soon as you get moving the temp will come down faster with the extra fluid capacity. Over 40mph, the fans are useless. I was going to swap mine out to the oversized, but my car got totaled.
 

engineermike

Well-Known Member
Joined
Jul 15, 2018
Threads
16
Messages
4,119
Reaction score
3,483
Location
La
Vehicle(s)
2018 GTPP A10
I had the fans on a 2015 f-150 and was pretty happy with the performance at the time….but again….I have no data to back that up.
 

vtknight

Well-Known Member
Joined
Nov 24, 2020
Threads
5
Messages
262
Reaction score
157
Location
Canada
Vehicle(s)
2019 Mustang GT
Get the oversized heat exchanger. I did the fans on my 18, but if I did it again I would do the oversized. You probably won't be sitting in traffic as much as you thought, and as soon as you get moving the temp will come down faster with the extra fluid capacity. Over 40mph, the fans are useless. I was going to swap mine out to the oversized, but my car got totaled.
This is also my understanding - stop and go traffic and the staging lanes for fan value. Racing - larger intercoolers for better cooling flow all of the time. I also have a cooler. Additionally - my understanding is that when moving the fans actually block air flow. Thus I went larger IC.
 

Sponsored

J17GT

Well-Known Member
Joined
Apr 21, 2019
Threads
6
Messages
540
Reaction score
447
Location
IL
Vehicle(s)
2017 Mustang GT PP
I also went with the oversized heat exchanger. It is impressive how fast the temps drop as soon as you start moving.
 

J17GT

Well-Known Member
Joined
Apr 21, 2019
Threads
6
Messages
540
Reaction score
447
Location
IL
Vehicle(s)
2017 Mustang GT PP
Here is a pic I found that shows the size difference.

02EE5037-E59B-4711-9690-026A4C62DCE4.jpeg
 

ZPD

Well-Known Member
Joined
Jul 10, 2018
Threads
24
Messages
200
Reaction score
87
Location
TX
Vehicle(s)
2017 GT Premium
If you aren't going to a track I would put some serious thought into the fan setup if I was you. I have the larger heat exchanger but I don't see the traffic that you do in Danville or that you will in Houston. When I am sitting at a stoplight my IAT will go 30-40 degrees above ambient but once I get moving it will drop down to 5-10 degrees above ambient. I couldn't imagine being stuck on the 680 or 580 for 45 mins (I lived in NorCal for 19 years) and just watching those IAT's climb.
 

Sponsored

engineermike

Well-Known Member
Joined
Jul 15, 2018
Threads
16
Messages
4,119
Reaction score
3,483
Location
La
Vehicle(s)
2018 GTPP A10
I also went with the oversized heat exchanger. It is impressive how fast the temps drop as soon as you start moving.
Thats the same regardless of LTR size and is a function of the stagnant air in the manifold heating up from the surrounding metal and rotors whipping it up. As soon as you move the hot air is consumed and cooler air replaces it. This is obvious if you log MCT over a 20+ minute drive.
 

engineermike

Well-Known Member
Joined
Jul 15, 2018
Threads
16
Messages
4,119
Reaction score
3,483
Location
La
Vehicle(s)
2018 GTPP A10
Here is what I'm trying to explain. This is a log from 25 minute drive, small LTR and no fans.

White is coolant temp. You can see it come up fast and stabilize once it reaches the thermostat and fan setting.

Green is speed.

Blue is IAT(1). It holds steady except when speed goes to zero/stopped.

Yellow is MCT/IAT2. MCT and IAT are scaled the same.

Observations: MCT slowly increases for the first 12-14 minutes of the drive then stabilizes at around 20 deg over ambient. WOT stints seemed to have basically no effect. Also, extended cruise at 70-80 mph didn't seem to bring it back down, causing me to doubt my earlier thought that the fans work. Yes, MCT increased when stopped/idling and dropped once moving, but what would you expect when IAT(1) also spiked up and dropped back down? In fact, the IAT2 and MCT are nearly unison during long idling.

1623427879982.png


If anyone has the big LTR or fans, I would love to see the same data.
 

vtknight

Well-Known Member
Joined
Nov 24, 2020
Threads
5
Messages
262
Reaction score
157
Location
Canada
Vehicle(s)
2019 Mustang GT
Here is what I'm trying to explain. This is a log from 25 minute drive, small LTR and no fans.

White is coolant temp. You can see it come up fast and stabilize once it reaches the thermostat and fan setting.

Green is speed.

Blue is IAT(1). It holds steady except when speed goes to zero/stopped.

Yellow is MCT/IAT2. MCT and IAT are scaled the same.

Observations: MCT slowly increases for the first 12-14 minutes of the drive then stabilizes at around 20 deg over ambient. WOT stints seemed to have basically no effect. Also, extended cruise at 70-80 mph didn't seem to bring it back down, causing me to doubt my earlier thought that the fans work. Yes, MCT increased when stopped/idling and dropped once moving, but what would you expect when IAT(1) also spiked up and dropped back down? In fact, the IAT2 and MCT are nearly unison during long idling.

1623427879982.png


If anyone has the big LTR or fans, I would love to see the same data.
I think this is valid - but I don't see the downside to a HX with double the size. Also - with fans - their value is questionable once moving (none). The blocking of air flow is also a big deal to me (by the fans themselves. I have to believe the larger HX must lower IAT's better than the smaller unit. Especially with a cooler.
 

S550AC11

Well-Known Member
Joined
Feb 14, 2017
Threads
3
Messages
77
Reaction score
45
Location
Dixon, CA
First Name
Aaron
Vehicle(s)
17 PP GT
I went with the standard exchanger and have no regrets. If I make repeated Mexico passes iat2 never climbs above 30-35 above ambient. 35 tops and if I cruise for a minute it's back to 30 or less. It would take about 10-15 minutes to get to +15-20 cruising on the freeway. In town it stabilizes around +30.

I read a ton of posts from Department of Boost on here and FB about this topic before I ordered my kit. He says the bigger exchanger is too thick and will restrict airflow through the cooler and air will take path of least resistance which he says is around the core. The standard kit is still bigger than the upgraded VMP unit. As for fans, he doesn't like those either. Another restriction and the fans don't have much output compared to the radiator fan. His suggestion is to "fence" the exchanger and radiator and let the big fan do the heavy lifting. There were some VMP guys on FB that did this with great results.
 

LethalPerformance

Well-Known Member
Diamond Sponsor
Joined
Sep 5, 2014
Threads
328
Messages
3,241
Reaction score
1,978
Location
Fl
Vehicle(s)
2020 Shelby GT500 CFTP, 2021 Whipple'd F150
If it's mainly street driven and will be in traffic a lot the dual fan one is what we typically recommend. If it's a street/strip car or dedicated drag car then the oversize one. Feel free to give us a shout on the kit itself and we'll do our best to make it a great deal for you.

Thanks!
Sponsored

 
 




Top