Hood vents

[Morris]

Originally Posted by strictlypersonl

You are correct. He isn't.

I get a kick out of folks trying to figure out what we have done...... and all my National Championship cars have been fun as folks are always trying to figure out what is going on and why the cars were so fast. A few comments I have on this subject since I'm trying to pass on the knowledge is as follows....

To compare any Cobra to KMP259 is like comparing Apples and oranges .... they are not even close ....

Your drawing is of a GT car which we built many and a Cobra is not even close on that drawing ....

6" windshield ..... 4" tall reversed hood scoop.... air vents in the hood .... complete flat bottom.... splitter ..... rear wing.....suspension mods.

My point is each car is on it's own merit and needs..... depending on how you anticipate to use the car is how you prepare it.... KMP259 was prepared to run on a race track and is very difficult to drive on the street as the motor is unruly and Sunoco is quite expensive at $10.00/gal.

Some of the things you are saying are right ...but it depends on what speed you are running.... some of the thing are just not right and should not be judged unless you know what you are talking about....

Many folks don't take the time to think out what is going on when one change is made and the effect is has on the other parts.

All of my references are to KMP259... and without a big windshield all of your theory's go out the window.....

Infact the above drawing really doesn't apply to a cobra except for the hood and on a Cobra you have a lot more lift under the car as that is where the air goes and lifts the car as it has no other way to escape the engine compartment unless you have the wheel well open for it to get out.... this creates a higher pressure under the hood and doesn't allow air to flow thru the radiators like it should.

As soon as you pack the front opening with air and it fill the engine compartment and the only way for it to get out is the wheel wells ....as you go faster you are putting more air in under the hood then can escape...... and so you start lifting the car as the only other place for the air to get out is the bottom of the car..... that's why many Cobras get lite at 150mph.....
There are ways to create a lower pressure under the engine area so you get air flow thru the radiator but there is only so much air you can get out of the car as the speed goes up.

When you get up in the 160mph plus range you have to control the air just like a suspension and get it to balance front to rear so the car tracks and brakes down a straight away under control and with a solid stance.

Those tricks are proprietary to each racer and only a few share their knowledge with others.

I guess to say I'm wrong is fine with me ..... but until someone can beat us.... then I'm not changing anything and know right now it works at very high speeds ..... and would be happy to compare lap time anytime.