rocker arm ratio.

[buckhorn76]

for anyone not familiar with the principal and the geometry, here is a good concise article. https://www.google.ca/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&sqi=2&ved=0CC4QFjAA&url=http%3A%2F%2Fwww.jegs.com%2Fs%2Ftech-articles%2Frocker-arm-ratio.html%26title%3DRocker%2BArm%2BRatio%2BExplained&ei=3heOUaS6AYafrAGg1YDQBQ&usg=AFQjCNFjIYBJXiqFmMgIYCOl7PKxQQiVyw&

sig2=FRxXYyAUssnN6BH5B9jYKg

well, that didn't work, let's try again.

https://www.google.ca/url?sa=t&rct=...MgIYCOl7PKxQQiVyw&sig2=FRxXYyAUssnN6BH5B9jYKg

 

[Keith Tedford]

People should read and understand the part highlighted in red before throwing on a set of high ratio rockers and thinking that all is well. New rocker arms may hit the valve spring retainers, retainers may contact the valve guide or valves might just meet the piston with the extra lift. Valve spring coil bind can be a possibility. Any one of these can be catastrophic. Higher rate valve springs will generally be needed too. If clearances are good, you can have roller rockers and the benefits of higher lift at the same time. It's all too easy to create a bomb rather than the rocket that you were intending to build. Dean Ireland won't get caught in any of these traps as he is an engine builder. It's self taught people like myself who don't learn enough before trying this stuff that get burned. Not everyone is handy to Manny's shop. If so, Chris Straub, given your engine build data, can come up with a cam profile that will work very well with your combination. Welcome to Straub Technologies. . .The Source of Performance. I have spoken to him on the phone ordering some Ferrea valves and he sounds like a decent guy who knows what he is doing.

 

[buckhorn76]

also it's important to be aware that with a change in geometry or stiffer springs that you may not get away with pressed in studs anymore. a change to the screw ins might be mandatory.

 

[Keith Tedford]

When you start to modify the basic engine, there are a lot of things to consider. Nothing is ever as easy as it first appears. I have an awful lot to learn about our Corvette before I do anything. Even then, I don't have the equipment to tackle most of the major stuff. It's nice to know Manny's shop is around in the event of a major problem and I can be confident that the work will be done right.

 

[buckhorn76]

that's the nice thing about the shark.....just about everything i learned in my youth still applies. i only open the hood on my tundra to check fluids etc. - there's not a whole lot i can even identify under there !!!

 

[Keith Tedford]

Same here with the Corvette. Back in '69, the Chevelle service manual cost about $3 at Alger Press in Oshawa. Today, for our car, it is over $200 and it takes two big thick books to cover it all. With our Jimmy, you have to work from the under side to change the plugs and move the power steering pump out of the way to get at the front plug buried behind it. A bit of a nightmare. For the do-it-yourself type of guys, there is a real advantage to sticking to a C4. There are a ton of aftermarket pieces to make them perform very well too. You're going to be building yourself a real sleeper. My kind of car.

 

[Arun]

It's funny at how people get carried away with rocker arm's, especially in the LS world.

The only time I think there beneficial is if and when you want to turn your motor to 8K plus.

I know alot of Ford guys who went from 1.6 to a 1.5 ratio just for the extra stability at hi rpm.

 

[buckhorn76]

yes, exactly, why dish out for a high dollar camshaft and then change the geometry ? it's always wise to discuss your plans with a trusted engine builder.