[grivera]

Originally Posted by blykins

So, what is the OF cam?

According to SD's site: 236/245 dur @ .050" lift .578"/.582" lift with 1.52 ratio rockers 112 lobe sep

http://www.sdperformance.com/viewPro...productID=1816

[blykins]

Originally Posted by grivera

According to SD's site: 236/245 dur @ .050" lift .578"/.582" lift with 1.52 ratio rockers 112 lobe sep

http://www.sdperformance.com/viewPro...productID=1816

To the OP then.....I would be looking at the cylinder heads to see if it's even necessary to run a 1.65 rocker. If the heads have been flowed and you can see a substantial flow increase from .550 to .650 valve lift, it would be something to weigh the pros and cons of.

If you gain single digits or lose flow at that lift, I certainly wouldn't go to the trouble of running a higher ratio rocker.

[Steve C.]

blykins....

They are Comp Magnum High Lift hydraulic roller lobes 3122B & 3120B

.3800" / .3830" lobe lift.

As mentioned in the link above Dave Bischopp states he often uses the Crane 99893 springs installed at 1.780-1.800".

At 1.785" installed height I've seen them at about 145 lbs on the seat after run in with that spring.




.

[blykins]

Are the 1.65's set in stone? Is your install height measured with a locator/spring cup?

You have to watch really closely about cutting the spring seats that amount. There are things that lie underneath that you don't want to hit.

I would look at a +.100" set of valves.