my engine has basic ole stamped steel rocker arms, i have always ran 1.5 rollers but ran across good set of full roller 1.6s. does anyone have insite on if it would be ok to slap them on? I'm running a mild cam nothing big, i just know the stamped steel one are not even true 1.5
do you know what the total valve lift with the 1.5 rockers are now? what will it be with the 1.6 rockers?
Should be fine. Import roller rockers are not true 1.6's either, usually. Only way to know is to check the cam lift. You'll need a solid lifter for that. That doesn't go along with "just slapping then on", I realize.
Sure don't that's why I'm iffy about doing it,I'm pretty sure will need new pushrods.but the piston slap I fear
when i first got my 64elky it had a 350 with double hump327 heads unknown cam and 1.6 rockers only on the exhaust valves.ran and sounded good.was supposed to be some kinda speed trick to give the exhaust more lift.i dont know
You could have geometry issues or coil bind issues, that's why you check it. You might have increased the spring pressure enough to pull a rocker stud, again that's why you check it. The rockers could interfere with the valve covers, maybe. If you could possibly hit the Pistons with the valves because of 1.6 rockers you really have much bigger problems anyway. When the Pistons are up the valves are too.
True for the compression stroke, but not for the exhaust stroke. You really do need to know the piston to valve clearance. The early 265 SBC's were known for the valves hitting the pistons, even with a pretty mild cam. Those notches in the piston are there for a reason.
I guess I ***umed a stock 350... 929 or 930 cam .266 lobe lift, ...399 at valve ... x 1.6 = .425 at valve. Stock cam , .050, .060 deck , you have plenty of room. Now, what have you?
True.. Should be checked anyway. May have been drilled , with guide plates..So far, we don't know. We don't even know that it's a Chevy.
Stock pushrod holes were the guide plates of today. If you need the clearance by drilling out the holes, guide plates will be needed and then taller valve covers especially if you go to stud girdles. Don't get me wrong because I would do it if the spring and piston clearance were good.
You will have to change the push rods to a different length. Read up on how to measure for the correct length.
We ran 1.6 rocker arms on the exhaust all the time on our round track cars. No bid deal with a stock cam. If you are worried just don't do it without checking everything. Just buy a set of stock type 1.6 rockers and put them on the exhaust. Most stock rockers are not a true 1.5 anyway. They usually check at 1.42 to 1.46. That's why they sell the blueprinted ones that are true 1.5. Isky always added a few thousands to their stock eliminator cams to make up for the rocker arms .
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