Way too much hot air with the windows down

[Porter]

This is a characteristic of the car. You're clearly accustomed to cars that vent the engine bay up over the windshield. In this car the aero kicks the hot air from the front rad out to the sides of the hood. It's not complicated.

I get that it bothers you. We all hear you. But it's not something that bothers everyone.

 

[Emiro]

For me it's not a deal breaker but kind of a nuisance.... I live in FL and like to drive windows down most of the time and AC on. I'd be nice if something cool looking could be fabricated.

 

[netsinah]

I for one, thank the OP R35_J for starting this thread and his comments in his original post. While others may not share his concerns, he had a question which he wanted answered and he's adding to our "Forum knowledge" about the Emira. I think these are some of the main purposes of this Forum. I invite people to approach different viewpoints with that in mind and consider that you may have a question which makes sense only to you, but you should feel welcome to ask it on this Forum so we can all expand our horizons and better enjoy the Emira. We all have different degrees of experience with cars in general and the Emira in particular, so there will no doubt be questions which some feel are "elementary" but allowing people to get answers/help, and sharing our knowledge with them, should be encouraged. My 2 cents.

 

[B r I a n]

I remember watching a video a year or two ago on U-Tube that mentioned how hot air from the hood vents funnels into the car when driving with the windows down at low speeds. If I lived in a hot climate and drove low speeds with the windows down a lot, I would probably choose a car did not vent through the hood. I think there are only 2-3 out there. That said, so far in DC (has been in the 90s for the last month or so ) it has not bothered me. I actually think in the late fall and winter it will be kinda nice. Not every car is for every person, every design discussion is a give and take.

 

[DerTheDer]

Here is one option. May be pricey though.

 

[Emiro]

Here is one option. May be pricey though.

View attachment 47210

Damm..... funny this sort of no gap clamshell still looks pretty good! Despite the hack... probably still better looking than 99% cars on the road included the beloved cayman

 

[ADC]

Here is one option. May be pricey though.

View attachment 47210

This makes my brain hurt.

 

[Emiro]

I remember watching a video a year or two ago on U-Tube that mentioned how hot air from the hood vents funnels into the car when driving with the windows down at low speeds. If I lived in a hot climate and drove low speeds with the windows down a lot, I would probably choose a car did not vent through the hood. I think there are only 2-3 out there. That said, so far in DC (has been in the 90s for the last month or so ) it has not bothered me. I actually think in the late fall and winter it will be kinda nice. Not every car is for every person, every design discussion is a give and take.

Much certain it depends on the weather, but here in FL on 95 degrees and up it's not nice. It'd be nice if there was some type of (subtle) deflector that could be added / removed depending on the season..... just dreaming..... first world problems

 

[ADC]

Much certain it depends on the weather, but here in FL on 95 degrees and up it's not nice. It'd be nice if there was some type of (subtle) deflector that could be added / removed depending on the season..... just dreaming..... first world problems

I feel for you man. If only there was some way you could, like, condition the air to be cooler and less humid, while the windows were up...

 

[kitkat]

Some sort of deflector at the mirror base would likely moderately improve both the radiator heat and wind seatbelt noise issue. The is the same issue that plagues a ton of cars with airflow that goes around the sides of the car like the Supra. They make stick on diverters for these. and you could probably 3d print to try something.

It’s been 100F for 3 days here now in California and this issue doesn’t bother me yet, but some are more sensitive to heat than others.

 

[Nova]

I just did some driving to test this specific phenomenon. I see what others mean, the hot air from the radiator follows the curve of the car and washes over the side windows. The vent air also becomes much warmer than ambient. I did this in muggy 85 degree weather and it was not objectionable. I noticed the hot air from the vents more. I didn't really feel that much hot air coming in through the window but did feel that the air in the middle of the window is hotter than above or below.

 

[Speedy Emira]

@GRP any kind of wind/deflector product you could possibly create?

Sorry as an Emira owner you will be banned from adding air deflectors on the edge of the widows. My grandad had one on an old Datsun and thought he was super cool.

Joking aside, what car do you drive because all info shows the i4 gets a lot hotter?

 

[gdotp]

It’s a sports car…….

 

[JimH]

Original aero design sketch from 2019….

 

[Bimmernate]

Well…. On the other side of this, when it is cold out I bet that heat will feel great when the windows are down.

It’s just a characteristic of the car and design…not a big deal

 

[Hell4Leather]

Original aero design sketch from 2019….View attachment 47219

I don’t understand…..why does the hot radiator air mix with the cool air flowing into the side intakes? I would think this air flow is counter indicated as cold air is best for the engine. Wondering what clever solution Lotus had for the Emira.

 

[seriously]

Half window roll down seems the best practical option.

I don’t understand…..why does the hot radiator air mix with the cool air flowing into the side intakes? I would think this air flow is counter indicated as cold air is best for the engine. Wondering what clever solution Lotus had for the Emira.

the trade off of this design is that the airflow creates real downforce on the front end. That’s pretty cool and very unusually for OEM spec cars.

Honestly the airflow design on this car is wicked. There is also flow coming out of the rear tires window and underneath the car. So you have suction effects of the underbody work, topside downforce front and rear and airflow to manage air turbulence around the wheels.

I’ll take some hot air as a result.

 

[ef_arime]

Thanks for sharing your thoughts on the airflow design. Speaking of downforce, I’ve been eyeing JUBU’s front splitter. It seems to be the only splitter around that’s functional, given how there’s an entire substructure to it. Does anybody here think there’s any material effect on downforce? I just want to make sure it’s not going to worsen things and possibly create lift. Thoughts? Any alternatives? Thanks.

 

[R35_J]

I drive my cars with the windows down 95% of the time. It's pretty crazy to me that some people think not being able to drive with the windows down is just an acceptable characteristic of a car.

 

[seriously]

Thanks for sharing your thoughts on the airflow design. Speaking of downforce, I’ve been eyeing JUBU’s front splitter. It seems to be the only splitter around that’s functional, given how there’s an entire substructure to it. Does anybody here think there’s any material effect on downforce? I just want to make sure it’s not going to worsen things and possibly create lift. Thoughts? Any alternatives? Thanks.

I don’t know. I would suggest if you are considering functional front splitters you pair it with a wing else you might be introducing imbalance to the downforce front and rear. No one wants a loose rear end. You can accommodate with suspension tuning etc, but things can get complicated. Emira stock already has a front spoiler of sorts. I’m sure it’s functional and part of the airflow design. If you never track it or take it near the limits I don’t think it will matter.