http://www.cranecams.com/index.php?s...8&lvl=3&prt=38
Was looking up somethings on preload on one of my dom. V-8's and I had forgotton about these. I wonder if that be an answer to a higher lift cam shaft. Just and idea late at work here.
wp
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http://www.cranecams.com/index.php?s...8&lvl=3&prt=38
Was looking up somethings on preload on one of my dom. V-8's and I had forgotton about these. I wonder if that be an answer to a higher lift cam shaft. Just and idea late at work here.
wp
was reading up on spring tension while looking for pics of a lash cap installed on a honda or similar OHC motor.
Turns out there is no mechanical loss of power from the valve train having to open a valve against heavier spring tension because the other valve that is closing is helping to rotate the cam so the two forces cancle eachother out.
So higher spring tension will ensure your valves stay closed and don't bounce which can reduce power and possibly damage the valve or valve seat. Oh and this is good for higher RPM as well as low. They said you could increase tension by adding shims to the retainers but then you run the risk of valve spring coil bind which is bad also.
Oh to check for the right geometry they used a marker and marked the top of the valve stem, rotated the crank a few times by hand, and then checked the wear on the valve stem to see if the wear was centered.
Im sorry im not being that clear.
Afaik there are no cams with more LIFT available for our cars A20 motor. I was thinking by making the valve tip a little longer (.100") the cam lift would be increased. Sorta like using high ratio rocker arms in domestic V-8.
wp
i think most of the cams ive seen for the a20 have pretty decent lift, but you dont want to get too crazy. I personally think duration has much more effect than lift in hondas
you won't get more lift from adding caps there just for correcting geometry from high lift cams and also help reduce wear on the valve tips. The only ways you will increase lift is from changin the ratio on the rockers angle or having a cam with more lift. Making the valve longer will make no difference at all, if you think it does you need to seriously go back to reading about how OHC engines work. I think your getting confused make the valve longer would just increase the length and the valve would be stuck open thus killing all compression when the tappet is re adjust for the cap it would just move the tappet further up and close the valve shut and then you'd be back at square one again with the same amount of lift, same as if you increase the height of the valve seat to seal the valve it would be no benefit as the raised seat would take away teh extra valve length you would have gained. I think you just had a homer simpson moment DOH so never mind stick with the reprofiled cams and 10-11mm is fine for out engines there is a point that no matter howmuch extra lift you give a certain size valve your not going to gain anymore flow and duration is theonly other way to increase flow and with our size valves 10-11 mm is pretty much the limit especially on stock valve springs and platforms, 12-13mm maybe benefitial on big valve conversions but you'd have to have some custom work done on the camshaft ( to produce the extra lift), valves, seats, springs and retainers as well as those loverly little caps you so nicely pointed out to help keep the geometry correct and to avoid coil bound on the springs which at 11mm your pushing it any higher the springs will bind and you'll destroy the cam and rockers.
oh sorry,Quote:
Originally Posted by Oldblueaccord
I thought you had a high lift cam and was trying to change where the rocker made contact.
