rod to stroke ratio
Thread Starter
Staging Lane
Joined: Nov 2001
Posts: 50
Likes: 0
From: Houston
rod to stroke ratio Does anyone know what the optimal rod to stroke ratio is? The longer the rod the less stress it puts on the cylinder walls but at what point does it become too much? To keep CR up in a destroked motor you can use a longer rod but does that hurt its ability to rev higher? Basically to sum it up, what are the principles of rod/stroke ratio?
FormerVendor
Joined: Nov 2001
Posts: 3,065
Likes: 6
From: Houston, Tx.
Re: rod to stroke ratio Just to give an example most modern headed race engine don't seem to go for rod ratios over 1.75 anymore even when they can get them and will make the deck smaller to save weight and get better packaging if it's allowed. Some race engines go as low as 1.50 nowadays even for endurance engines. The C5R is a good example and it's WON several 24 hour races now for Chevrolet.
FormerVendor
Joined: Nov 2001
Posts: 3,065
Likes: 6
From: Houston, Tx.
Re: rod to stroke ratio A shorter rod will usually allow earlier power whereas the longer rod motor will rev a little longer before the heads stall out. These differences are fairly tiny to almost nonexistent though usually. Shorter rods have lower pumping losses but slightly more friction. All in all it isn't that important of an engine spec really.
