Solid cam questions.

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J

Johnny from Chicago

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How does a solid cam and lifter setup work. Won't the top end starve for oil with no hole in the lifter and pushrod and rocker arm?
 
Well if you are talking about LA, R or RB they don't oil through the pushrod anyway. The oil comes through the head into the rocker saft to oil the top end.

With engines that oil through the push rod there is still a hole in the lifter that allows oil to pass through it up the push rod to oil the top end.

A solid lifter just doesn't have a piston in it that takes up all the clearance in the top end. Because of that you have to set valve lash with some clearance to allow for expansion as the engine heats up.
 
The shape of the lobes are different between hydraulic cams and solid cams. Since there needs to be some clearance in the valve train a solid cam has a shallow ramp to take up the clearance gradually that's not in a hydraulic cam.

There's likely some people that have mixed lifter types on cams but it's not going to have a long life if you do.

If you have pump up problems why not purchase anti-pump up lifters. You will need to have an adjustable rocker to use them, but you will need that to go to a solid cam anyway.
 
How did you know ahead of time that the cam would have enough piston to valve clearance? I want to get a new cam but I don't want to buy one and go ooooooops. I don't really have enough compression right now for a roller. (only going to be 9.1:1 with the new Edelbrocks) But what do you think about milling 10 cc' s out of them to get 10.1. Is the increase in compression worth the cut? (factory said they're good to cut up to .060... this cut will take .040.
 
I'm running 11.5 cr with ported X heads and a dana 60 with 3.91s. You need to get a cam that works with your end plan. Don't buy twice. In short if you are never going to change your gears or compression then get a cam that works with what you have. You do not want to over cam your car and you need to think about what gas you want to run. Form a plan and work to it. Look at where you want to be in the end and don't think about the extra bit of power you want now. If in the end you want to run in the 12s save your money for parts that will get you there. First you need a plan man then spend the cash.
 
You can run the Edelbrocks with the 9:1, but I wouldnt. If you are milling to remove the deck surface, you must also mill the intake flange, or the intake itself, to have things line up properly. Under .020" is not a problem. More than that removed, means bolt holes dont line up, and I always think ovalling the holes make syou look like a hack. You fix the bolt issue, but the ports also dont line up, and that costs power. So, now you're milling two surfaces per head, and you have the small chamber you need. But, now the pushrods are not going to fit properly, and you'll need to either order the corrrect ones, or shim the rocker shafts to get lifter preload correct. Your 284 cam has a lot of duration for its lift, but to be sure, you should take an afternoon and pull a head to check what you have now. This will only be a guide, but you'll be in the neighborhood for choosing another cam.
 
The only way to know if the cam fits besides installing it and seeing yourself is to find someone who has the exact parts you have to start with.
Then the blocks must have the same deck height along w/ the rods and pistons in concert with the head used.
In short, It may be very hard to know exactly for sure.
If your deck is factory advertised height and your heads uncut, you have a decent chance of finding a match.
 
On milling the head for comp ratio increase, it's a fine way. Though you should have built it that way first, your now spending extra money to adjust your plan. Thus the saying, "Make a plan and stick to it." Because if you don't, it will allways cost more.

Cams work in compresion ratio ranges. When there not in the range or intended useage as well, things go bad.
At a 9.0-1 ratio, you can still make decnt power. More compresion, more torque.
So if you mill the heads, remember this also moves the valves that much closer to the piston.
 
I'm checking my clearances without the .040 head gasket and the heads will be cut at about .043 so its a wash. I'm calculation the into the clearances and I have .220-.230 on both.
 
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