Finished!! Forged piston block, Custom valve head (flowbenched)

[mwinkle353]

no kidding. That;s why it's not adding up, somehow

[turbovanman]

Unless my thinking is wrong, your shim is too thick. You should have added .067" or less. I realize about ratio but my thinking is in this case, it won't matter.

[Ondonti]

cam pushes up on the Rocker which pivots on a tube, then pushes down on the valve/lifter
Cross flow heads......
look

[turbovanman]

I know how it works, I work on them all the time. Based on I just did a regrind on a Honda with adjustable rocker arms, I would say .100 is too much unless you got really wild cams. But I could also be wrong, just throwing out idea's. I have never measured etc to figure this stuff out soooooo! And if your valves worked before and since you added the shim they don't, that could be it.

Also you say no oil pressure, it could be that as the lifters won't harden and of course, the valves won't open.

[Ondonti]

stock cam is .350" lift
These are .450" lift
Stock duration 182
Mine 278

removed .067" material from cam

[Tim_K]

Have you put a compression gauge on any of the cylinders and got a reading, or does it just sound like there's no compression?

Is there any free play at all in the rockers with the cam lobe on the base circle and the lifters not pumped up? I'd think you could move the rocker a bit by hand if the lifter had no pressure on it and the cam wasn't lifting at that point in its rotation, and the lifters weren't shimmed to the point of being solid against the valvetrain.

The shim thickness math sounds right, but I still think a thinner shim is needed.

I'm sure you've checked the timing mark alignments already, so I won't mention that.

[Ondonti]

Hav'nt checked the cam timing as Im not wanting to work on the car.

I did do a compression check, zero compression. I did the compression check because it sounded like "no compression"

I was looking for the "boat motor glugging in the water when trying to start up" and all I heard was the starter. I never actually got oil pressure.

[Ondonti]

i guess I could pull the front valve cover on the spirit and see how those rockers "feel" when I push/pull on them compared to the duster.

[m90daytona]

0 compression doesnt sound right. the cams have to be shimmed wrong. what has changed since the motor ran last time compared to now?

is your motor no longer a "tolerance" motor w/ the new cams? if you spun the crank w/ the timing belt off and the cams in the head you could have bent the valves.

[Ondonti]

and that would not cause Zero compression.

[m90daytona]

yeah i just cant think of anything else besides the shims. in this case all shims would have to be wrong. they would almost have to be open at all times to have zero.

[Ondonti]

Okay well this is sorta lame as far as funny things go.

I checked the cam timing and it was correct.

I pulled the rockers again, this is probably the 10th time AT LEAST.

I measured the difference of the cam base circles with feeler gauges (not really accurate so i tried different places).

Anyways I came up with .067" material removed which happens to be the exact calculation (probably coincidence since depending on where you put the feeler gauge you get different measurements) I made when calculating how much material was removed based on the lift increase.


So Im stuck with what to do since it would seem I need .100" shim for .067" material removed from cam.

[Ondonti]

im gonna try 2 washers which is .066" shim.

3 washers was actually measuring about .105" shim when installed (2 small washers 1 bigger).

[Ondonti]

Put the rockers back in with the new smaller shim.
27 degrees outside ick :P I torqued the rockers down then quit. Not sure why i like to work at night. Doesnt go so great in the winter.

[Ondonti]

Well im just remembering now that my valves are longer then stock so that is probably why my lifters are being funny.
I had thought of this before months ago but I forgot.
Picture is crooked but you can see the difference.

If I was intelligent I could probably measure the difference on the picture then propotionally adjust for the valve being smaller in the picture


I tried blowing the picture up real big and it was about .040-.050" difference assuming the valve seat is the same distance from the bottom of the valve.
I may have to go back to 1 shim......Im not sure now.......Looks like the ferrea valve actually has its valve seal closer to the bottom of the valve so that would make the difference in length even greater.

My machinist knew I was using a reground cam and he knew what the difference was so IM assuming he did some of this on purpose.

Im guessing that I wouldnt get .450" lift either without the longer valve. I didnt really think of that before.
I basically just asked him "can I get .450" lift" and after he played with it for a week he said "yes"

Seems that He sorta cheated to get more lift out of the head.
Feel free to look at the pic and see what you think........it almost seems to me there might be a .070" or so difference and that would mean I should only use 1 shim (.030")