Finally found the 172 inlet valve size.......MAx power for t

[BenR]

282bhp!!!!!!

this assums that there is no restriction to flow from inlet or exhaust system and valves stay the same size.

formula:

maxpower = 35 x 35 x 3.1416/4 x 8 = 7696.92 sqmm
max power = (valve adjustment) 7696.92 x 1.10 = 8466.612
maxpower = 8466.612/30 = 282
maxpower = 282.22bhp

for a balls out race car, with money not an issue and larger valves (on average you can fit 7% lager valves to engines) the max power is 320.7bhp.

 

[Glennclio16v]

282bhp!?!?!

I would be sooooo impressed if anyone got theirs even remotely close to that!!

 

[BenR]

so would i!!!
but saying that S B D have vauxhall 1.6 16V pumping out 246bhp....so if you can sort the VVt them it would be possible..itll be mostly work on the head and valves.

 

[Hitman]

Renault Clio Sport 282 - its got a nice ring to it

 

[Griff]

Ben whats all the maths about? Can you explain to us non mathematicians what it all meant?

Griff

 

[BenR]

Well its rather basic really. you just find the valve area diameter squared x Pi, multiply by 8 cause there are 8 inlet valves in the engine. adjust for an extra 10% area because its a 16V motor (for an 8 V you would decrease the area, depending on whether it was parallel or inclined etc)
then you divide by 30 becasue its roughly 30mm per hp.

 

[bluerxe]

Look <a target="_blank" href="http://www.pumaracing.co.uk/pp03.htm" target="_blank">here for a really good read up on the calculations involved. While you there read the rest of the site. This guy REALLY knows his stuff.

 

[Rick]

Surely this relies on a few constants such as air:fuel ratio, the exhaust valves being able to cope etc?
Also what effect would having a turbo make. As you would have a greater volume of oxygen to burn therefore potentially more power. Or am I just confusing the issue?

Rick

 

[Nick Read]

My understanding is that a turbo can be accounted for by altering the apparent capacity of each cylinder. The higher the boost pressure the greater the effective size of the cylinder.