The 35ci engine will be a 18hp with single carb or a 20hp with two barrel carb. The 35ci engine has a bigger bore and stroke than the 30ci engine. They share the same connecting rod, and the valves and ports are the same, the 30ci engine has smaller combustion chambers. I have seen a few 16hp horizontal engines with two barrel carbs. The 35ci engine has a plastic fan on the flywheel and the 30ci has cast on fins. They share the same camshaft.  Hope that helps.   Ryan.

The real reason for the roller cam is so a huge profile camshaft can be used without having contact problems between the lobe and lifter, its actually not for friction at all, the advantages come from the cam profile and not the fact that it has a heavy roller on the end of the lifter. As mentioned because of the mushroom style of the briggs lifter there is no reason for a roller set up, its a nice light strong efficient design that can handle a lot of camshaft.    Ryan.

The aluminum rockers are the absolute best for OEM rockers. There is also a shaft mounted steel rocker that doesn't look very strong. The bandolero engines use the steel style pedestal mount rockers that are in the picture with quite a bit of camshaft and they seem to be holding up but they are keeping the RPM around 5600rpm. The so called heavier purple valve spring is recommended for use with the aluminum rocker only, if that says anything.     Ryan.

Hi guys, don't forget to check the pushrod angle, you might be messing up the geometry of the valve train and changing the characteristics of the camshaft at the same time. Just because you have a 1.6 ratio rocker doesn't mean it will be correct, you can have a rocker arm that is ten feet long and it still being 1.6 ratio. Also keep in mind that some rockers are pretty heavy and would take more hp to operate than they would make, especially by the time you have enough valve spring to make them work.But I'm sure in some cases they may be needed. Just something to kick around.       Ryan.