Volumetric efficiency from hp

[68corvette]

Is there a formula to estimate VE% based on engine HP?
Engine is a 1600cc, 12:1cr, peaking at ~8000rpm 220hp.

[steve cowan]

Is there a formula to estimate VE% based on engine HP?
Engine is a 1600cc, 12:1cr, peaking at ~8000rpm 220hp.

as per superflow 110 manual
ESTIMATED VOLUMETRIC EFFICIENCY FOR GASOLINE BURNING ENGINES
volumetric efficiency = 5600 x HP x 100% / (RPM x CID)
volumetric efficiency = 123 x KW x 100% /(RPM x LITERS)

ESTIMATED VOLUMETRIC EFFICIENCY FOR ALCOHOL BURNING ENGINES
volumetric efficiency = 4750 x HP x 100% / (RPM x CID)
volumetric efficiency = 104 x KW x 100% /( RPM x LITERS)
i converted from cc to ci and done the math,the manual says if your calculations go beyond 130 % for naturally aspirated the power or rpm inputs are incorrect.
hope this helps.

[jarmoyp]

Dyno lies.

It´s not gonna be 220hp/ 8000 rpm 1600cc NA.

[digger]

Dyno lies.

It´s not gonna be 220hp/ 8000 rpm 1600cc NA.

144 ft-lb from 1600cc (1.47 ft-lb/CI) is totally plausible

[Dan Timberlake]

FWIW OP is achieving 160% vol eff per dynojet formulae posted by others.

[Stan Weiss]

97.64 ci - 220 HP @ 8000

Now I need to guess at a few things. So lets say the A/F ratio was 13:1 and the engine had a BSFC of .44 and 1.0 Correction Factor then the VE = 121.6%

Stan

[David Redszus]

Dyno lies.

It´s not gonna be 220hp/ 8000 rpm 1600cc NA.

144 ft-lb from 1600cc (1.47 ft-lb/CI) is totally plausible

Plausible but....

That combination would result in a BMEP of 15.4 bar. That is Formula One territory.

Very unlikely for a two valve engine but possible for a very, very, well developed 4 valve engine.

[68corvette]

This engine is a Z16XE, 16 valve engine.
It is my friends engine, I just ported head, specified camshafts and intake / exhaust manifold dimensions.
Dyno graph is identical to Vanniks simulator, but it does not give VE% and I am qurious if ther would be more to be gained.
Engine noses over now after 8200rpm and owner is making some changes as it should pull to 9500rpm.

There are 2L engines making more HP per liter at same RPM, but those have been measured with race gasoline.

Personally I am happy with the results, but there seems to be still room to improve if we are now at 121VE%, so better to continue development. I am sure competition does

[68corvette]

Lets see if this works, I put the dyno graph to instagram:

[ptuomov]

Nice result.

[John Wallace]

I think this web site/page helps on answering many questions on VE and BMEP and others.

BMEP

[jarmoyp]

Lets see if this works, I put the dyno graph to instagram:

From the dynograph I can not see the 220hp/ 8000rpm.
There is 218.8 hp/ 8480 rpm. That is plausible.

[ptuomov]

215 hp at 8000 rpm is still a great result.

[jarmoyp]

215 hp at 8000 rpm is still a great result.

Estimated hp, yes it is.

This is a chassis dyno.

[swampbuggy]

68Corvette, tell us more about this engine-----Bore and stroke, induction setup, exhaust, etc. Mark H