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Discussion Starter #1
in an otherwise stock 350 chevy how much gain should I get by using the BB stock rocker arms?
Augusto.
 

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King of my Man-cave.
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Years ago, guys would cobble BBC rockers onto SBCs for the added lift. Now, there is no need to do that because there are so many off-the-shelf 1.6 and other rockers available.

tom
 

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No need to do it now a days.

I agree with Machine shop Tom. If you read Smokey Yunick's "Power Secrets" book, he talks about the mods that had to be done to the rockers to do this. Why would the do this? Because the racing sanctioning bodys at the time said you had to use a stock factory part. Smokey being who he was figured they didn't say what motor it had to come from...1.75:1 ratio on a big block versus 1.5:1 on a stock small block. That's why. As MS Tom said today's wide variety of rockers and ratios available makes the mods unnecessary. You also had to modify the sheetmetal valve covers too for clearance.
 

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Discussion Starter #5
is it worth the expense of buying diferent ratio rockers or should I better get a bigger cam and stay with the std ratio ?.(my current rockers are in good condition )
Augusto
 

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Augusto said:
is it worth the expense of buying diferent ratio rockers or should I better get a bigger cam and stay with the std ratio ?.(my current rockers are in good condition )
Augusto
Going to a bbc ratio of 1.7 will hurt piston valve clearance so that would have to be checked and with that much ratio and if its a flat tappet cam make sure the lobe is designed for that much rocker arm if not it may tear the nose of the lobe off.

We use some 1.8 ratio rockers in some of the circle track engines we build and on these engines we machine the cam tunnels to a BBC size and use speicial cam bearings and use the Shchubeck lifters on a GOOD cast core that is designed for that type of rocker ratio and we do see quite a good in horse power and torque gain with this set up..
 
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