torque calculation

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penny
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Joined: Mon Feb 26, 2007 8:30 pm
Location: adelaide

torque calculation

Post by penny »

found this in an efi laptop program, will pass it up for evaluation. Tip: A 10.1 compression engine will usually make 1.1ft. Lbs. of torque per cubic inch. 9.1 is approximately 1ft. lb.per cubic inch. While 11.1 will make 1.2ft.Lbs per cubic inch. Example: A 383 engine at 10.1 compression would calculate to this:383x1.1=421.3ft. Lbs. A383 at 9.1=383x1=383ft. lbs. A 383 at 11.1=383x1.2=459.6ft.Lbs.
momec
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Joined: Sun Sep 11, 2005 8:15 pm

Post by momec »

A currant Pro Stock motor makes 1.7 Ft Lb per cube

Currant Supercar makes 1.58 Ft Lb if its a Ford

Pro motor 2.65 Hp per cubic inch plus

Supercar 2.1 Hp per inch

Pro motors have very high compression/ rev to 10k plus and fuel is $48.00 litre (Roo 25)

S/Cars are pegged at 10:1 comp rev limited at 7500 and are now running E85

Chris
Acme Racing #251
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Greg Watters
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Post by Greg Watters »

Chris how many of those use performance enhancing fuels, roo25 for example has a nice pop to it :wink:
if comparing apples to apples you would have to make a call on "effective compression ratio's "for chemical or mechanical supercharging

my 1300cc bike for example if turned the boost right up will be around 280-300 ft/ lbs and effectively around 17-20 :1 comp ratio.
hawkwind racing
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Post by hawkwind racing »

chris those HP per cube are very low for such developed race cars , compaired to jap compact sport cars , even the current liter sports bikes are making close to 3 Hp per cube on 98 pump petrol
fastest busa in Captains flat pop. 200
momec
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Joined: Sun Sep 11, 2005 8:15 pm

Post by momec »

Correct Hawk but are well on the money for TWO vavles per cylinder.
We spend huge money on two valve heads and the best thing I've seen on our ducks guts flow bench up to .500 inch lift is a Porshe factory 997 style head. (4 valve)
Greg, your right the fuel makes a difference, my example was to compare real dyno figures with computer animation as it were.

The Pro stock guys would all love to run cheaper fuel but as long as one runs the rocket stuff they all have to to keep up.

Bikes have always been streets ahead in engine design on road based stuff.

Chris
Acme Racing #251
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