Another how much HP with a twist....

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af2
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Another how much HP with a twist....

Post by af2 » Sun Oct 14, 2018 4:12 pm

I have not found anywhere how to calculate The Brick Aerodynamics of my 33 Willys Coupe to determine the HP from the MPH of 138 MPH. Just wondering since the 377 is coming out and replacing with a totally different set up. The 377 is going into the daughter in laws 57 Chevy. The 33 Willys weighs 2300 lbs. A pic so you can see the brick front.
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Re: Another how much HP with a twist....

Post by Ron E » Sun Oct 14, 2018 4:23 pm

Small area, but bores a dirty hole in the air. You already know that.BUT, damn it looks good!

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Re: Another how much HP with a twist....

Post by lefty o » Sun Oct 14, 2018 5:06 pm

to get a good accurate estimate, id think you would need to know the drag coefficient of the car to do any real math on it. if it were me, id take a swag at it as 2-3mph slower than something like a vette or camaro etc.

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Re: Another how much HP with a twist....

Post by af2 » Sun Oct 14, 2018 5:11 pm

lefty o wrote:
Sun Oct 14, 2018 5:06 pm
to get a good accurate estimate, id think you would need to know the drag coefficient of the car to do any real math on it. if it were me, id take a swag at it as 2-3mph slower than something like a vette or camaro etc.
That was the Question and I think it way more than that... But I don't know and is the reason fore the post.
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Re: Another how much HP with a twist....

Post by redliner » Sun Oct 14, 2018 5:16 pm

af2 wrote:
Sun Oct 14, 2018 5:11 pm
lefty o wrote:
Sun Oct 14, 2018 5:06 pm
to get a good accurate estimate, id think you would need to know the drag coefficient of the car to do any real math on it. if it were me, id take a swag at it as 2-3mph slower than something like a vette or camaro etc.
That was the Question and I think it way more than that... But I don't know and is the reason fore the post.
Wallace calculators has front end drag coefficient calculators.

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Re: Another how much HP with a twist....

Post by af2 » Sun Oct 14, 2018 5:26 pm

Ron E wrote:
Sun Oct 14, 2018 4:23 pm
Small area, but bores a dirty hole in the air. You already know that.BUT, damn it looks good!
Thanks Ron! The hole bored is the reason for the post. My son and I built the chassis for his senior project in 2005 and have ran since 2006. Going faster as years go on.
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Re: Another how much HP with a twist....

Post by af2 » Sun Oct 14, 2018 5:28 pm

redliner wrote:
Sun Oct 14, 2018 5:16 pm
af2 wrote:
Sun Oct 14, 2018 5:11 pm
lefty o wrote:
Sun Oct 14, 2018 5:06 pm
to get a good accurate estimate, id think you would need to know the drag coefficient of the car to do any real math on it. if it were me, id take a swag at it as 2-3mph slower than something like a vette or camaro etc.
That was the Question and I think it way more than that... But I don't know and is the reason fore the post.
Wallace calculators has front end drag coefficient calculators.
I still can not figure it out. Oh well it is not a straight calculation.
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Re: Another how much HP with a twist....

Post by af2 » Sun Oct 14, 2018 5:31 pm

Looking at 3' x 2' then 5'x 1' HMMMM? Total of 5' x 4' ? And Flat?
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Re: Another how much HP with a twist....

Post by redliner » Sun Oct 14, 2018 6:12 pm

af2 wrote:
Sun Oct 14, 2018 5:31 pm
Looking at 3' x 2' then 5'x 1' HMMMM? Total of 5' x 4' ? And Flat?
I think I estimated my flat nose 42 Stude to be about the same as a pickup

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Re: Another how much HP with a twist....

Post by travis » Sun Oct 14, 2018 6:35 pm

Beautiful car!

There actually is a way to calculate drag coefficient fairly accurately by measuring coast down times...ie 100mph to 50 mph (or whatever you choose). We used to do this in advanced physics back in college...unfortunately that was about a million years ago and I have long since forgotten how to calculate it

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Re: Another how much HP with a twist....

Post by af2 » Sun Oct 14, 2018 6:57 pm

travis wrote:
Sun Oct 14, 2018 6:35 pm
Beautiful car!

There actually is a way to calculate drag coefficient fairly accurately by measuring coast down times...ie 100mph to 50 mph (or whatever you choose). We used to do this in advanced physics back in college...unfortunately that was about a million years ago and I have long since forgotten how to calculate it
LOL Travis I never went to physics because the teacher was the most boring person you would meet.
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Re: Another how much HP with a twist....

Post by af2 » Sun Oct 14, 2018 6:59 pm

redliner wrote:
Sun Oct 14, 2018 6:12 pm
af2 wrote:
Sun Oct 14, 2018 5:31 pm
Looking at 3' x 2' then 5'x 1' HMMMM? Total of 5' x 4' ? And Flat?
I think I estimated my flat nose 42 Stude to be about the same as a pickup
Did you come up with a formula? Thanks Adam
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Re: Another how much HP with a twist....

Post by David Vizard » Sun Oct 14, 2018 8:02 pm

Ron E wrote:
Sun Oct 14, 2018 4:23 pm
Small area, but bores a dirty hole in the air. You already know that.BUT, damn it looks good!
It surely does!!!!!

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Re: Another how much HP with a twist....

Post by Keith Morganstein » Sun Oct 14, 2018 8:16 pm

af2 wrote:
Sun Oct 14, 2018 4:12 pm
I have not found anywhere how to calculate The Brick Aerodynamics of my 33 Willys Coupe to determine the HP from the MPH of 138 MPH. Just wondering since the 377 is coming out and replacing with a totally different set up. The 377 is going into the daughter in laws 57 Chevy. The 33 Willys weighs 2300 lbs. A pic so you can see the brick front.
The “brick front” isn’t necessarily bad, it’s the multiple different surfaces, and the overal height of the vehicle.

Plenty of drag under the car too.
Automotive Machining, cylinder head rebuilding, engine building. Can't seem to quit #-o

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Re: Another how much HP with a twist....

Post by af2 » Sun Oct 14, 2018 10:47 pm

David Vizard wrote:
Sun Oct 14, 2018 8:02 pm
Ron E wrote:
Sun Oct 14, 2018 4:23 pm
Small area, but bores a dirty hole in the air. You already know that.BUT, damn it looks good!
It surely does!!!!!

DV
Gees Thanks My son and I appreciate the kind words! Coming from David
and Ron is awesome I will let Nick know! So how do we calculate the drag?
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