Angle valve case, Parallel valve cylinders?

[Pheonix137]

Can you fit parallel valve cylinders to an angle valve case? Obviously pushrod length changes, But I cannot see anything else that might be a problem - with the exception perhaps of the shroud tube angle?

[jrs14855]

This used to be very common in the aerobatic community. Most popular was Piper Seneca One crankcases(angle valve engine) with front mounted governor to accommodate constant speed prop. Parallel valve cylinders. The previous iteration of Firewall Forward built some of these engines.

[cajunwings]

Originally Posted by Pheonix137

Can you fit parallel valve cylinders to an angle valve case? Obviously pushrod length changes, But I cannot see anything else that might be a problem - with the exception perhaps of the shroud tube angle?

Shroud tubes look the same on all cylinders. The "angle" part happens right at the valve itself.

Don B

RV-9 Rebuild in Progress

[g zero]

Why ????? Seams like a waste of HP potential

[mahlon_r]

from a crankcase perspective the two styles of cylinder's are interchangeable. The cases are the same. So the cylinders will bolt up regardless of type they are to any 320,360 standard case. but the intakes, push tubes and rods rockers etc. are all different.
Good Luck,
Mahlon

[jrs14855]

Originally Posted by g zero

Why ????? Seams like a waste of HP potential

On the Pitts S1 this was done to keep the weight and balance under control. Allows the use of a lightweight constant speed without major issues with CG. Parallel valve engine can be hot rodded to 200 hp.
The Pitts flies much nicer if the CG is kept where it belongs along with keeping the total weight under control.
If you can live with a fixed pitch prop no need for the IO crankcase.