Help please!! Valve clearence issues
I need to know if its possible to use a .631 Intake and Exhaust lift cam on stock heads and pistons, and still be able to clear everything, if not what needs to be done to make it work? The exact specs on the cam are 229/242 .631/.631 114LSA, And also if I do install this cam, will I need to go with a dual valve spring setup?
Thanks in advance,
Anthony
Thanks in advance,
Anthony
Originally Posted by OOZ28
I need to know if its possible to use a .631 Intake and Exhaust lift cam on stock heads and pistons, and still be able to clear everything, if not what needs to be done to make it work? The exact specs on the cam are 229/242 .631/.631 114LSA, And also if I do install this cam, will I need to go with a dual valve spring setup?
Thanks in advance,
Anthony
Thanks in advance,
Anthony
Are you sure about 229 duration and .631" lift? That is a nasty ramp. I would definitely go with a dual spring on that and one with a lot of seat pressure. Also, I would be very careful and measure the rocker clearance with that much lift unless you are going with aftermarket rockers spec'ed for that lift. I'm pretty sure the stock rockers are good to .650" lift, but that is for optimum retainer size, i.e. a larger spring diameter would have a larger retainer diameter and that would lessen the rocker to retainer clearance.
As far as p/v clearance, it depends on valve event timing more than lift. The p/v clearance will change for any cam depending on where it is installed, what lsa it was ground with, and the velocity of the ramp.
One last thing I would like to add would be with that much lift the cam base circle will be pretty small. With stock heads you would probably need longer pushrods than stock, probably 7.450". Just guessing here, but I think you get the picture.
As far as p/v clearance, it depends on valve event timing more than lift. The p/v clearance will change for any cam depending on where it is installed, what lsa it was ground with, and the velocity of the ramp.
One last thing I would like to add would be with that much lift the cam base circle will be pretty small. With stock heads you would probably need longer pushrods than stock, probably 7.450". Just guessing here, but I think you get the picture.
Last edited by ArKay99; Aug 11, 2005 at 09:47 AM.
So with longer pushrods, and a lower ratio rocker arm I could make this work? heres the link with to cam http://www.lingenfelter.com/store/ls1-gt1-1.html Im still new to all this cam stuff, so any help is greatly appreciated.
Originally Posted by OOZ28
So with longer pushrods, and a lower ratio rocker arm I could make this work? heres the link with to cam http://www.lingenfelter.com/store/ls1-gt1-1.html Im still new to all this cam stuff, so any help is greatly appreciated.


