no cowl/engine cover + rainwater = ruined 6th cylinder spark plug

martymil

Major General
Sep 6, 2017
3,331
1,907
0
Down Under
Ride
S65 1m
Here is my setup on my 1m
24305
 

The Convert

Captain
Jun 4, 2017
1,487
1,052
0
Ride
335
Hot air rises and will never let fresh air enter the engine bay between the windscreen and bonnet especially while being rammed in through the radiator and ic whilst driving
This is not necessarily true. While hot air does rise in a static environment, turbulence inside the engine bay can force the hot air down and out the trans tunnel if a high enough pressure wave of cooler air is forced in. Also, the area where the hood meets the windshield is a low pressure zone designed to pull air in for hvac purposes. So, it will pull exterior air into the engine bay through the coweling area. This is just science. Whether or not this is a bad thing for engine bay cooling is another question entirely. As far as water getting in...thats another question as well.
 
  • Agree
Reactions: fmorelli

martymil

Major General
Sep 6, 2017
3,331
1,907
0
Down Under
Ride
S65 1m
When the factory cowl is installed the hot air has no where to go except around the transmission.

Remove the cowl and go for a drive and see how much cooler your engine will run, no matter what it's a win win no matter which way you choose to go.
 

Panzerfaust

Lieutenant
Jul 3, 2018
637
438
0
Chicago
Ride
E92 335i
This is not necessarily true. While hot air does rise in a static environment, turbulence inside the engine bay can force the hot air down and out the trans tunnel if a high enough pressure wave of cooler air is forced in. Also, the area where the hood meets the windshield is a low pressure zone designed to pull air in for hvac purposes. So, it will pull exterior air into the engine bay through the coweling area. This is just science. Whether or not this is a bad thing for engine bay cooling is another question entirely. As far as water getting in...thats another question as well.

When the factory cowl is installed the hot air has no where to go except around the transmission.

Remove the cowl and go for a drive and see how much cooler your engine will run, no matter what it's a win win no matter which way you choose to go.
100% agree with Marty on this one. Yes cooler air is designed to hit the cabin filter area for Hvac purposes on the stock setup, but that's with the engine bay being completely sealed off. When you do the cowl mod along with BMS filters you open up a space for air to escape and air is sucked into each filter from above, and it's certainly noticeable imo. Both while driving and stopped I can see heat exit my engine bay and noticed cooler temps right away. Between my 335D suction scoop, BMS filters, cowl mod and PSP FMOC I've noticed significant-to-drastic improvements in cooling all around.