80's Aerodynamic Trends...
 

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I have a question about an aero feature that was common possibly in the 70's and certainly in the 80's. Seen on rally as well as track racers. I don't know what to call them and therefore my internet searches have been fruitless. Can someone please tell me the purpose of these top fender mounted (near the hood) "strakes"?

To pull air out of the wheel wells and lower preasure

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JC, I realize now the pic I provided is confusing. I'm not referring to a "vent" but rather the thin moldings that I assume bolt on the "wings" on either side of the bonnet. My theory is it helps for down pressure or cleaner air routing, it "looks" like a good addition, but why then don't we see it anymore?

https://cimg2.ibsrv.net/gimg/rennlis...a4bce71f29.jpg
Okay, so more research shows others reference them as "hood strakes" also. Could they be used to stabilize the vehicle? Based on this wiki, perhaps? https://en.wikipedia.org/wiki/Strake_(aeronautics)

It helps force the air over the hood VS having the air role off the hood. Also acts a stabilizer of sorts kinda like a rudder would do.

I remember them being called hood/fender wind splitters or wind splits. Kamei and Zender used to make some back in the days.

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Thanks for the insights. Seems like a value add to me. Wonder why we don't see them anymore... dated fashion perhaps?

Vortex generators are useful but ugly. Could be these are obsolete for same reason.

Yeah. I found it interesting the Ford Group 5 Capri... a very bad ass racecar... with a lot of attention to *everything* including aero.... aerodynamic features, many of which to this day are considered excellent performers... *added* these. Best as I can tell they weren't on the earliest versions of the car, but got added mid way and stayed for the duration. For myself they are of interest because I'd rather not have a huge splitter because my car is mostly a street car, and so I'm looking at alternative method of increasing downforce on the front other than long front splitter.

I can only surmise that these are no longer a worthy option. Reason being is that we've seen a lot of Aero development since the 80's and these are no longer seen anywhere.
With all the CFD and Tunnels available we would have seen a continuation of these hood-fins if they were worth it.

Alright, I'll toss them into the "don't use bin". Thanks for your input everyone.

THere's also a lot of things we don't see because of rules. So, hard to say what is useful or not. Aero is a constant fight for the best thing they can do within the rules allowed. Sometimes aero rules are done to even slow down the cars ;)

Perhaps this can be the case but not with these particular parts in question. Look to Time Attack cars. They have the highest levels of downforce and aero development via the most liberal rules. I can't recall any Time Attack car with these on them. If they were a worthy part then they would be there.