AFR valves
AFR valves I was checking the rocker valve wipe on my AFR 230v2's yesterday and noticed something. It seems like all my intake valves are taller then my exhaust valves. It also looks like the tip of the intake valves are slightly different then the exhaust. Is this normal?
Are they solid valves or hollow? Have you checked the wipe pattern? With the Yella Terra rockers this is a critical step and will tell you if the valve stem heights will affect the wipe (assuming they are indeed different). Are the retainers/keepers set for installed height change?
I believe they are solid but I'm not 100% sure. I know the exhaust is because I can see the part number on the valve tip by the keepers. I'm trying to set up the wipe pattern but I made a mistake and didn't check it with a solid lifter. I might take one head back off and make a solid lifter out of one of the old lifters. I used Fel-pro 1041's so I should be good to take the head off and still reuse the gasket since I never ran the engine(still on the engine stand).
With the hydraulic lifter in there I got the best wipe pattern on a .125 shim. I had some TFS 7.500 pushrods laying around but that only brought me to about 3/4 of a turn on the LS7 lifters so I would guess I would need either a 7.525 or 7.550, if the wipe pattern stays the same on the solid lifter.
With the hydraulic lifter in there I got the best wipe pattern on a .125 shim. I had some TFS 7.500 pushrods laying around but that only brought me to about 3/4 of a turn on the LS7 lifters so I would guess I would need either a 7.525 or 7.550, if the wipe pattern stays the same on the solid lifter.
Tip heights are never exact....different diameter valves and where they sit in the chamber will effect that, stacking of tolerances on valve job depth and the actual length of the valves will effect that.
If you face the valves it will make the tip height deeper.....you get the point.
If your extremely detail oriented you can order custom pushrod lengths for both intake and exhaust.....thats what I do on all my complete engines. Every now and then I can order 16 of the same length pushrods (because the tip heights are within .005) but I usually end up ordering eight and eight.....this will net you the same preload on all the lifters but its not a mandatory situation nor is this situation limited to AFR heads.
We are usually within .020 or less from the factory but some of the heads I "Mamofie" and install aftermarket valves have an even larger disparity. Its not an issue as long as you purchase different length pushrods for intake and exhaust.....the wipe pattern of the rocker will be slightly different but its a very minor change and doesn't effect squat at the end of the day.
Get a solid lifter.....find out what length pushrod you need on intake and exhaust to give you zero preload, then add the amount you want for lifter preload to that figure and order the pushrods accordingly. A very straightforward procedure.
PM or call me if you have any questions....I can help you with tech advice and obtaining the pushrods you need if you like.
Thanks,
Tony
661-705-8508
If you face the valves it will make the tip height deeper.....you get the point.
If your extremely detail oriented you can order custom pushrod lengths for both intake and exhaust.....thats what I do on all my complete engines. Every now and then I can order 16 of the same length pushrods (because the tip heights are within .005) but I usually end up ordering eight and eight.....this will net you the same preload on all the lifters but its not a mandatory situation nor is this situation limited to AFR heads.
We are usually within .020 or less from the factory but some of the heads I "Mamofie" and install aftermarket valves have an even larger disparity. Its not an issue as long as you purchase different length pushrods for intake and exhaust.....the wipe pattern of the rocker will be slightly different but its a very minor change and doesn't effect squat at the end of the day.
Get a solid lifter.....find out what length pushrod you need on intake and exhaust to give you zero preload, then add the amount you want for lifter preload to that figure and order the pushrods accordingly. A very straightforward procedure.
PM or call me if you have any questions....I can help you with tech advice and obtaining the pushrods you need if you like.
Thanks,
Tony
661-705-8508
Thanks Tony. I will be taking the head back off tonight to check the pattern the right way this time. I think the valve height is actually closer then I thought. I think the difference in the way the tips look was throwing me off.
Yup, I'm just crazy. The valves were alot closer then they looked, only about 5 thou difference or so. I guess the way the valve tips looked different through me off, that or my eyes are just not level
Now it's time to take one head back off and convert some of my old lifters to solid for proper wipe pattern checking.
Now it's time to take one head back off and convert some of my old lifters to solid for proper wipe pattern checking.
I'm glad I did take a head back off and check with a solid lifter. With the new LS7 lifters in there I was getting the best wipe pattern with a .125 shim. With the old lifters converted to solid, I was getting the best pattern with a .080 shim.
Now with some trickflow 7.500 pushrods I get to about .7 turns to the 22lbs setting. If that equals to about .033 preload then I guess I should get some 7.550 pushrods?
Now with some trickflow 7.500 pushrods I get to about .7 turns to the 22lbs setting. If that equals to about .033 preload then I guess I should get some 7.550 pushrods?
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