HELP with Rocker Arm Geometry!

[Torinoman]

Do you have standard ratio rockers to test this with?

[86lxttop]

Do you have standard ratio rockers to test this with?

1.6 rockers? No I don't but the ones in the for pics were 1.6's...I returned them and got some better quality scorpion 1.7's

[Torinoman]

From the pics I've seen on the interwebs the location of those stud holes seem consistent with other flowtec heads.

You could always take them to a machine shop to have them take a look.

Also proper geometry can be a complicated thing that won't be the same for different heads and rockers. People see the old SBC magazine trick of just rubbing a valve tip with a marker and then adjusting the push rod so it leaves a mark in he middle. This likely gets you in the ballpark for in line valve heads but might not be 100% accurate.

What I've been told is that you want the push rod and rocker perpendicular to each other at mid lift with the rocker tip close to centered on the valve tip.

Have you played with an adjustable push rod with the head on the motor to see if you can find a good setup?

You may just need a different push rod with that head and rocker combo.

[86lxttop]

From the pics I've seen on the interwebs the location of those stud holes seem consistent with other flowtec heads.

You could always take them to a machine shop to have them take a look.

Also proper geometry can be a complicated thing that won't be the same for different heads and rockers. People see the old SBC magazine trick of just rubbing a valve tip with a marker and then adjusting the push rod so it leaves a mark in he middle. This likely gets you in the ballpark for in line valve heads but might not be 100% accurate.

What I've been told is that you want the push rod and rocker perpendicular to each other at mid lift with the rocker tip close to centered on the valve tip.

Have you played with an adjustable push rod with the head on the motor to see if you can find a good setup?

You may just need a different push rod with that head and rocker combo.

I haven't yet with these heads...I decided to really build the engine now with all forged, studed and girdled stuff. Just need a good forged crank, rings, main studs, and bearings. The other heads were 170cc 1.94/1.54 valve heads with .500ish lift springs and 1.6 Proform rockers. The new upgraded heads are 180cc 2.02/1.60's with .650 lift springs and 1.7 scorpion rockers. The old heads obviously weren't right whether that was the rocker stud holes being too close or what I've not most likely noticed was the problem was that the valve stems were too long causing the rocker arms to angle up too high on the valve stem. I've set my rockers on these new heads just to see how they look and the rocker seems very parallel and looks like it will work perfectly. But, yes once the engine is all buttoned up with all new parts I'll throw the heads on there and figure out what pushrod length I'll need.

[Torinoman]

So you haven't even checked with current heads?

[86lxttop]

I placed the rocker on the and it looks waaaaaaaay more correct. It should work