"Crank height"

[gonek]

Hello everybody
Greetings from Poland!

I'm new on this forum but I've read your topics for a long time and I would like to say thank you to the people who have created this website. Here I have found a lot informations about F1 technology. I'm interested mostly in F1 engine technology.

Could someone explain me exactly which dimension is the crank height? Yesterday I read one article in RET-Magazine and there were mentioned restrictions regarding F1 engines. One was - "58 mm minimum crank height". In F1 Technical Regulations it has been written "5.3.3 The crankshaft centreline must not be less than 58mm above the reference plane". I supose, both of this sentences describe the same dimension but second one is for me more understandable although I don't now exactly which is reference plane on F1 car. Is it the lowest plane on the car or is it the bottom plane of engine?
Thank you in advance for answers.

Regards

Gonek

[RH1300S]

The reference plane is the bottom of the car's chassis, which (I am pretty sure) is the bottom of the plank, the next plane above that is (I believe) called the step plane.

So, the centreline of the crank cannot be lower than 58mm from the bottom of the car's chassis.

[Ciro Pabón]

Just in case, yes, the reference plane is at the top (not the bottom) surface of the plank (skid block).

It is on top of the yellow line in this frontal view. The line represents the skid block (which is not a plane but has a definite 10 mm thickness):



Here you have a view from the side:



And this one is the top view:



Sorry if I'm being pedantic but I'm not sure everybody understands what the reference plane is (including me! ), and I find curious the fact that there is no definition of the reference plane in the summary of the technical regulations available at FIA site.

So, here you have this definition of a reference plane by Ciro... completely unofficial until validated by the forum.

That plank or skid block is NOT exactly the reference plane, but it is used as a way to know where it is, because article 3.13 says:

"Beneath de surface formed by all parts lying in the reference plane, a rectangular skid block... must be fitted".

So, the reference plane lies "on top of the top surface" of the skid block, if I'm allowed to put it that way.

The reference plane has to be defined before you attach the skid block, as article 3.12.4 says:

"The surface lying on the reference plane.... must first be fully defined before... the skid block is fitted."

Article 3.15 states:

"... no part of the bodywork, with the exception of the skid block in 3.13 above many under any circumstances be located below the reference plane."

So, the plane of reference is, truly, a plane at the bottom of the bodywork... or so I think. Is it?

The center (or the "centre", as article 5.3.3 states) of the crankshaft has to be 58 mm above the yellow line; that's what means "crankshaft height" in the first phrase gonek quotes, as RH1300S says.

[gonek]

Sorry if I'm being pedantic but I'm not sure everybody understands what the reference plane is (including me! ), and I find curious the fact that there is no definition of the reference plane in the summary of the technical regulations available at FIA site.

Thank you for good explaination and nice photos - they explain almost always everything. Now I know better what is the reference plane. I haven't found its definition at FIA Regulations as well.

Thanks and Regards

[scarbs]

Although 58mm is the lowest permissible crank height not all engines use that height. For example the Mercedes engine is a little higher, The feel its better to be on the safe side and have the crank a little higher off the ground and use a thicker sump.