Coweling and engine bay aero
- Thread starter The Convert
- Start date
More air through the gearbox tunnel is not inherently good. Keep in mind that if additional air goes through the engine bay, it will create more drag, and more air through the tunnel and under the car will create more lift. Also, the speeds you say are the issue are regularly hit in half mile and roll races, and I don’t know about you, but I would prefer a more planted setup at 150+ than one creating more front end lift than stock...
And you tested it that it creates lift, BMW capped the car at 155mph, do you think they would spend money on special underbonnet aero that they know the vehicle would never hit.
So put the cowl on if you feel that your 335 is a road going race car that needs to do 150mph + at every turn.
Been to a few roll racing events and the track is not long enough to hit 150mph
1/2mile yes you will and no lift was ever experienced , even at 200mph, by lord the car should have been doing backflips going by your reasoning.
So put the cowl on if you feel that your 335 is a road going race car that needs to do 150mph + at every turn.
Been to a few roll racing events and the track is not long enough to hit 150mph
1/2mile yes you will and no lift was ever experienced , even at 200mph, by lord the car should have been doing backflips going by your reasoning.
Marty, check the sarcasm and attitude. Literally everyone else in this thread wants to discuss aero upgrades and paths to do so. A large percentage of your posts are equivalent to you saying your way is the only correct way and the rest of us should just shut up and listen to you. You’re certainly entitled to feel that way, and that no aero work will amount to anything appreciable for these cars, but if that’s the case, why do you keep coming in here and posting? If you think there are appreciable aero gains to be made, then suggest them and let’s get people conversing about them. Don’t just try to stifle the conversation because you don’t want to have it.
Circling back to this. The undergrad only adds down force because it smooths out the air under the car. It does not do so by air pressure inside the engine bay. So, trans tunnel air coming through the engine bay would not add addition front end down force due to the undertray being under that air.
Correct me if that is not what you meant.
By removing the cowl your basically turning the bonnet into a bonnet scoop, which most muscle cars run at 200mph at the 1/2mile events.
By adding more air into the tunnel you basically add more drag but this is offset by making more hp due to the cooling effect.
The undertray actually stops front end lift by not letting the air from the hood scoop pressurise the air under the front of the car
causing it to lift, formula earlier provided and also adds to downforce yes, adding air in the tunnel will also help with rear end downforce
with the right diffuser.
There are only three outcomes you can have from having, not having or modifying the cowl.
The only negative effect the cowl removal or modification is drag at 150mph +.
So if you want to discuss aero tell me would more air through the tunnel with the right diffuser and a proper wing, would it add or decrease rear end lift ?
By adding more air into the tunnel you basically add more drag but this is offset by making more hp due to the cooling effect.
The undertray actually stops front end lift by not letting the air from the hood scoop pressurise the air under the front of the car
causing it to lift, formula earlier provided and also adds to downforce yes, adding air in the tunnel will also help with rear end downforce
with the right diffuser.
There are only three outcomes you can have from having, not having or modifying the cowl.
The only negative effect the cowl removal or modification is drag at 150mph +.
So if you want to discuss aero tell me would more air through the tunnel with the right diffuser and a proper wing, would it add or decrease rear end lift ?
Take aero, speed and safety seriously.
You guys are talking some instant death speeds and none of you have shit for safety equipment, nor do I for that matter. Just keep that in the same realm of thought.
You guys are talking some instant death speeds and none of you have shit for safety equipment, nor do I for that matter. Just keep that in the same realm of thought.
I've left my speed limiter on as my car will never see the speeds been thrown around here.
We hardly see any 1/2 mile events here in oz, not popular enough especially when the whole country is speed limited to 68mph.
In Australia the only legal way you might hit 150mph is down the straight of Easter Creek raceway for a sec at best before you have to jump on the brakes.
I guess the only place you can enjoy those speeds is in Germany.
We hardly see any 1/2 mile events here in oz, not popular enough especially when the whole country is speed limited to 68mph.
In Australia the only legal way you might hit 150mph is down the straight of Easter Creek raceway for a sec at best before you have to jump on the brakes.
I guess the only place you can enjoy those speeds is in Germany.
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I track my much-massaged single turbo 1M a lot. And as I'm a One Lapper (having run the One Lap of America 14 times in last 17 years), I've had the opportunity to drive time trials on tracks across the country in my marginally legal street car. On the banking of Daytona, when driving the road course configuration, I saw GPS-verified 172 mph.
i run a splitter and a serious wing and car is very well braked and suspended ;-).
Oh, and I run without the cowl and with hood vents. Have no measurements about the aero effectiveness of these mods.
Neil
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No one cares dude.
Go post in an Australian section of some car forum so people who have the same limitations can jack off to each other about how this thread has no relevance to each other.
In the states and many other places hitting above 150mph is common. I hit 150+ on the road off of the main highway on my way home from work in Massachusetts all day long.
Your negativity and bias is so obvious.
If VTT made a product that had a positive effect above 150mph you would be gushing over it.
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if you could be bothered, you could do sets of laps with and without the cowl, logging iat, water and oil temps, water pump duty cycle if you can.
Easy mate! We have feelings down here you know !
Literally every product in the VTT catalogue will help you go above 150mph, one good one which will help greatly is called a TURBO.
You sure about that? I mean ... that dude that set the Bonneville record on a motorcycle ... piss and vinegar that guy was baller. He's an Aussie I'm pretty sure.
Filippo
Never said Australia is the world, but it sure was one of the safest places until this Covid-19 shit.
But lets get back on topic.
Most likely 99.9% of people in these forums will never see 150mph +.
While most like the idea of being able to do it, in reality they wont.
Without someone testing the cowl in a wind tunnel which will never ever happen the cowl topic is moot.
Do a bit of research on hood vents and their pro's and con's, removing the cowl at under150mph just does that and is proven to be beneficial.
But lets get back on topic.
Most likely 99.9% of people in these forums will never see 150mph +.
While most like the idea of being able to do it, in reality they wont.
Without someone testing the cowl in a wind tunnel which will never ever happen the cowl topic is moot.
Do a bit of research on hood vents and their pro's and con's, removing the cowl at under150mph just does that and is proven to be beneficial.
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lots of dudes have set records on motorcycles... if your thinking of Burt Munro made famous by the movie "The World's Fastest Indian" he was a kiwi.
we like adopting any successful kiwi's as aussie's, so yeah your right, he was aussie... lol.
we have great 1/2 mile and 1000m event in my part of the country, last event with good weather top 5 guys all went > 200mph in the 1000m.
i am sceptical about how much difference the cowl will make, compared to other factors affecting the bonnet as simple as rake. but the topic doesnt deserve to be dismissed simply because the surface area is massive minor changes can have a significant impact on front end downforce (or minimise lift whichever way you want to look at it) - an average pressure difference of only 0.1psi is going to > 100lbs force on the bonnet/hood. ~50-60lbs is probably around the limits of what i can feel have an effect on lateral grip through 60mph corners.
no one needs a wind tunnel, the end result is measured with suspension potentiometers and temperatures sensors on track as direct measurements of the end objectives in the real world performance environment. the former is attainable for a serious enthusiast - its on my very long wish list, near the bottom somewhere.
we like adopting any successful kiwi's as aussie's, so yeah your right, he was aussie... lol.
we have great 1/2 mile and 1000m event in my part of the country, last event with good weather top 5 guys all went > 200mph in the 1000m.
i am sceptical about how much difference the cowl will make, compared to other factors affecting the bonnet as simple as rake. but the topic doesnt deserve to be dismissed simply because the surface area is massive minor changes can have a significant impact on front end downforce (or minimise lift whichever way you want to look at it) - an average pressure difference of only 0.1psi is going to > 100lbs force on the bonnet/hood. ~50-60lbs is probably around the limits of what i can feel have an effect on lateral grip through 60mph corners.
no one needs a wind tunnel, the end result is measured with suspension potentiometers and temperatures sensors on track as direct measurements of the end objectives in the real world performance environment. the former is attainable for a serious enthusiast - its on my very long wish list, near the bottom somewhere.
If you don’t want to have the discussion, then stay out of the thread. It clearly isn’t for you then. For the rest of us that want to have the discussion, we can continue. Like Australia, you aren’t the center of the universe.
actually it would be really cool to get one of these 1:18 scale models:
and do this:
that would be fun....
