Compression Ratio of F1 Engine

[megz]

Does anyone know of the information around compression ratio in the current V8's?

[Scotracer]

I recall it is around 12.5:1

[Ian P.]

It would be interesting to know if this could be higher or is it limited by the geometry of the combustion chamber..??
I understood that a number of years ago that the NASCAR engines were getting up over 15 to 1 until the rules police called "Enough" and imposed a limit.

[donskar]

It would be interesting to know if this could be higher or is it limited by the geometry of the combustion chamber..??
I understood that a number of years ago that the NASCAR engines were getting up over 15 to 1 until the rules police called "Enough" and imposed a limit.

Way back in the 1960s - 1970s American pushrod V8s were running as high as 14:1 (for drag racing) and I (VERY vaguely) recall that Ferrari 3 liter V12s also ran in that same range (?)

Anyone have a complete set of Racecar Engineering? There was an article in there about the Ferrari V12 and how Honda helped them develop it (really).

[donskar]

It would be interesting to know if this could be higher or is it limited by the geometry of the combustion chamber..??
I understood that a number of years ago that the NASCAR engines were getting up over 15 to 1 until the rules police called "Enough" and imposed a limit.

Way back in the 1960s - 1970s American pushrod V8s were running as high as 14:1 (for drag racing) and I (VERY vaguely) recall that Ferrari 3 liter V12s also ran in that same range (?)

Anyone have a complete set of Racecar Engineering? There was an article in there about the Ferrari V12 and how Honda helped them develop it (really).

[CMSMJ1]

I would have expected a touch higher compression than that..my motorbike has 12.5:1 compression and it is 20 years old!

[safeaschuck]

There will surely be someone on here better quilified to answer this than me, but....
Isn't half the problem trying to get the combustion chamber small enough to get the compression ratio high?
It would be more pronounced on large bore short stroke engines of which F1 is an extreme example. The Piston crown needs to be low enough in the centre to allow the valves clearance, and low enough round the circumference to give a large enough gap from the cylinder head to allow good flame propagation across the whole piston surface. If the piston nearly touches at TDC round the outside it may detonate in these areas.
Also you need a large enough chamber to get a good sized charge in... To get the comp. ratio high in a larger chamber you need a longer stroke. I imagine they have compromised between C/R and RPM's???