Achieving desired SS valve lift.....

[ss wannabee]

I know I asked this before...but am getting old and forgot.....

WHICH is better way?

Smaller lobe lift and LOTS of rocker arm ratio....

Larger lobe lift and lesser ratio....

Pros/cons of each way....

Which is more common today?

Would running stud-mounted rockers dictate pretty much what could be done?
(ie...ratios above 1.65 not available for stud mounts...)

Combo is 283 Chevy....on a budget...with the stud-mounted rockers....

[Jim Hanig]

The trend has been bigger cam or lobe lift and less rocker ratio. JimHanig

[Jeff Lee]

budget a shaft rocker system in!

[Alan Roehrich]

Get the lift at the lobe not at the rocker. Run shaft rockers. And all the pushrod that will fit.

To let you know how much I believe in what Tim and Billy told me about getting the lift at the lobe, I'm buying a half set of T&D rockers, because I bought 1.75:1 rockers for the intake last time, and I'm going back to 1.7:1. I can tell you that a 1/2 set of T&D rockers are more than 1/2 the cost of a new set. And not by a small amount. If I didn't think lift at the lobe instead of the rocker was important, I'd save myself a ton of cash.

[Kevin Panzino]

And why exactly is this all of a sudden in fashion??

With lower lobe lift, and higher rocker ratio's, a larger portion of the valvetrain mass undergoes lower acceleration. And that is nothing but good.

If you can move the lifter, the pushrod and half of the rocker mass less distance and less quickly for a given valve lift and rate, then how can that be bad??

high rocker ratios allow more 'area under the curve' of the valve for a given duration and given cam ramp..

It blows my mind, how all of a sudden high ratio rockers are now out of fashion, and the old ratios are back in....

Perhaps Im missing something, but there is nothing at all technically negative about high ratio rockers other than increased load on the lifter, cam bearings, pushrod, and thus potential pushrod flex,.. And roller cam bearings, large diameter roller lifters, and pushrod quality and design have taken care of that problem....

Tell, you what, its all fine with me, because all I have right now is a set of 1.7's, on the intakes and 1.6's on the exhaust, and I'd like to get some 1.8's, and 1.7's, so this means I should be able to trade someone and even make a few bucks, eh ??

So there you go, all you guys with the 1.8's Intakes and 1.7 exahusts on a SBC jesel shaft, thats OLD SCHOOL.. You are sooooooo lame.....

I have what you need right here... some 1.7's and 1.6's.. PM me asap, so you can trade with me, and you can go faster....

[Ed Wright]

I'm doing it all wrong. LOL

[ss wannabee]

Well...my engine program's not so stable anyhow...so I should be just fine...w/o the
shaft-mounts...

Just hoping that the car gets down the track....period!

[Alan Roehrich]

Originally Posted by Kevin Panzino

And why exactly is this all of a sudden in fashion??

With lower lobe lift, and higher rocker ratio's, a larger portion of the valvetrain mass undergoes lower acceleration. And that is nothing but good.

If you can move the lifter, the pushrod and half of the rocker mass less distance and less quickly for a given valve lift and rate, then how can that be bad??

high rocker ratios allow more 'area under the curve' of the valve for a given duration and given cam ramp..

It blows my mind, how all of a sudden high ratio rockers are now out of fashion, and the old ratios are back in....

Perhaps Im missing something, but there is nothing at all technically negative about high ratio rockers other than increased load on the lifter, cam bearings, pushrod, and thus potential pushrod flex,.. And roller cam bearings, large diameter roller lifters, and pushrod quality and design have taken care of that problem....

Tell, you what, its all fine with me, because all I have right now is a set of 1.7's, on the intakes and 1.6's on the exhaust, and I'd like to get some 1.8's, and 1.7's, so this means I should be able to trade someone and even make a few bucks, eh ??

So there you go, all you guys with the 1.8's Intakes and 1.7 exahusts on a SBC jesel shaft, thats OLD SCHOOL.. You are sooooooo lame.....

I have what you need right here... some 1.7's and 1.6's.. PM me asap, so you can trade with me, and you can go faster....

Well, good luck to you.

I'll stick with what I'm getting from the guys who developed the SpinTron and the guys who use it to refine my valvetrain components. All of whom say that weight/mass on the cam side of the rocker fulcrum is nearly irelevant compared to weight on the valve side.