Vented hoods bad for performance?

[bogart]

Downside is water in the engine bay

[bogart]

Originally Posted by hyphy1

I want that lip. hmmmm

iCarbon

[gmagnus7]

Thread revival: what's the actual benefit of these vented hoods, vs just removing the cowl, like with the BMS cabin filters?

I wonder what the actual difference in cooling would be, and the difference in downforce vs just a splitter.

[HondaGoneRogue]

Woooow. An ancient document unsealed lol.
I miss all these guys.
As for the hood, I'm sure the cowling removed wouldn't be that effective unless you are moving. The hoods with top vents would be slightly more effective at a stop, and probably even greater while in motion.

A lot of guys are of the belief that vented hoods or of any kind can provide relief to the plastics in the bay and therefore extend the life of a lot of the components that end up blowing apart. Especially the charge pipe.

Not sure if I buy that or see it as a better solution than upgrading the plastic parts. For performance, after intercooler, then yeah I guess.

[b3turbo]

What are the available choices of vented hoods for E82 ?

[gmagnus7]

Ahh gotcha. Who even uses the stock chargepipe lmao
I'll just stick with my cowl delete for now.

Originally Posted by HondaGoneRogue

Woooow. An ancient document unsealed lol.
I miss all these guys.
As for the hood, I'm sure the cowling removed wouldn't be that effective unless you are moving. The hoods with top vents would be slightly more effective at a stop, and probably even greater while in motion.

A lot of guys are of the belief that vented hoods or of any kind can provide relief to the plastics in the bay and therefore extend the life of a lot of the components that end up blowing apart. Especially the charge pipe.

Not sure if I buy that or see it as a better solution than upgrading the plastic parts. For performance, after intercooler, then yeah I guess.

[bbnks2]

Originally Posted by gmagnus7

Thread revival: what's the actual benefit of these vented hoods, vs just removing the cowl, like with the BMS cabin filters?

I wonder what the actual difference in cooling would be, and the difference in downforce vs just a splitter.

Cowl deletes do not help excavate heat at spead. Air ennters the engine bay from the cowl area.

If you want to vent the engine bay, you should do it near the front of the hood which would pull all the hot air out that just came from the radiator. The m3 has two small vents near the windshield because one of them is an intake and the other is fake.

[ShocknAwe]

Originally Posted by gmagnus7

Ahh gotcha. Who even uses the stock chargepipe lmao
I'll just stick with my cowl delete for now.

Cowl delete is accomplishing exactly the opposite of what you think.

[gmagnus7]

Originally Posted by ShocknAwe

Cowl delete is accomplishing exactly the opposite of what you think.

Well I think it pulls air in from the high pressure area near the windshield... so then does it pull air out?

Still creates a physical opening for heat radiation to escape as well.

[gmagnus7]

I guess my other question is: has anyone tested for the high pressure and low pressure areas? That would tell you where to put the vents, rather than assuming the best spot is in front of the radiator or whatever.

[bbnks2]

Originally Posted by gmagnus7

I guess my other question is: has anyone tested for the high pressure and low pressure areas? That would tell you where to put the vents, rather than assuming the best spot is in front of the radiator or whatever.

Yes, someone did: https://www.e90post.com/forums/showthread.php?t=1306425

Also, it's in the same place for just about every car. You can't really avoid the nose and the windshield creating areas of high pressure... You just see a LOT of poorly done hood vents :/ especially when it's a DIY effort and the person places them based on what looks cool rather then actual airflow function. But, look at every actual big name race car and you'll see the type of vents the data supports... Also, review the location of hood vents and air intakes that EVERY SINGLE car manufacturer uses... intake at the front fascia or cowl... expel air right after the radiator and on the sides right before the hoods starts to curve.

The only real OE exceptions are cars with top mount inter-coolers which use RAM AIR intakes on various places on the hood.

Lots of pics to look at in that thread along with data.