Cross Bolted Block

[BeastMaster]

Hi Guys. Would be most gratefull if someone can explain what a cross bolted RV8 engine is and why it is done.

Also some help in understanding what a flat plane crank is.

Any links to explain with pics would be most helpfull

Thanks Andy

[eesbad]

http://www.autozine.org/technical_school/engine/sm...

Good article on flat plane vs cross plane cranks...

[GreenV8S]

Cross bolting is the process of bolting the main bearing caps into the sides of the crank case. It prevents the caps from shuffling sideways under high loads, and also stiffens up the crank case.

[Geoff Ashcroft]

Cross-bolting is done to stop main bearing caps from moving, and is intended to give the bottom end of an engine block much greater rigidity. Can't speak about RV8's but we do it to our methanol motors (for tractor pulling) which involves fitting additional bolts through the side of the engine block and into the side of the main bearing caps. It's usually at 90-degrees to the main bolts. For us, the elimination of cap movement in a block means longer bearing life, though we do run 10-litre in-line sixes at up to 6500rpm and they have to withstand 100 psi boost pressure