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HP to weight formula


BadTony

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Can anyone discuss the science and math of how to calculate how much HP it would take to get a 3900+ lb car into the 10 second realm in the qtr?

 

 

It's all a mystery............................

 

But here's the answer.

 

For a 4000 lb car to do a 10.99et, it needs 715 at the flywheel and assuming a 20% loss, 596 at the wheels.

 

Here's how to find it:

 

 

http://www.cprparts.com/HPcalculator.html

 

Have fun.

 

:shift:

 

bj

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Can anyone discuss the science and math of how to calculate how much HP it would take to get a 3900+ lb car into the 10 second realm in the qtr?

 

 

 

can't get into the math, but here is a link to some software you can play around with; free version gives you 10 attempts I think

 

cartest

 

 

I have run into another direct entry site on the web, that I will post if I run into it again. There are apparently several other pieces of software out there, but you would probably have to do a search to find them.

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Here you go:

 

rwhp = (mph/244)(mph/244)(mph/244)*(weight of car with driver)

 

Considering that the GT500 (and most late-model stick shift Mustangs) lose 15% hp through the driveline, you can take the rwhp # from above and divide by .85 to get approximate hp at the crankshaft.

 

So, for example, Evan Smith at MM&FF went 117 mph in the 1/4 mile with a GT500. Assuming 4100 lbs (car + driver), that equates to 452 rwhp, which is approximately 531 hp at the crank.

 

A car that runs 10.90's in the 1/4 mile would go through the traps at about 126 mph (assuming it launchs hard with good traction). To go 126 mph with a 4100 lb car (car + driver), you'd need 564 rwhp, which is approximately 665 hp at the crank.

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What do you figure...?

 

Pulley Kit for 12/12.5 psi boost

(or Whipple 200AX 3.3L to assure the top-end if you have an extra $9G)

 

Higher pressure injectors

 

Low restriction air cleaner, throttle body, tube headers, catback 3" Flowmasters (or ???)

 

reflash

 

 

Gut interior, one good racing seat, battery in trunk,

 

Suspension tweaking and street slicks (maybe fiber fenders)

 

...and .... we're about there!!

 

If there aren't kits like this by SEMA LasVegas I'll be astonished!

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