In my last post I had ordered my pushrods. I actually lucked out and Comp Cams offers a kit for my exact setup with 7.725" intake pushrods and 8.684" exhaust pushrods. So I placed my order through Summit Racing. I have been getting most of my stuff through Summit because I find their service excellent. Most everything I have purchased from there is lower price then anywhere I have found and they ship very fast. I placed my order for the pushrods and it was shipped an hour later. I got the pushrods the next day.
The kit I got are the 3/8" thick pushrods which is what I need because that is the size of the pushrod guideplates on my cylinder heads. The guideplates do exactly what the name suggests. They hold the pushrods and actually hold the rockerarms from walking around side to side when the engine is running.
Next thing to do will be to perform the same checks as in my last post, but using the actual pushrods in place of the checking pushrods to see if I can get the same wear patterns on the valve tips.
In the picture below you can see the exhaust pushrod sitting nicely in it's guideplate.
Here is the wear pattern I got with the new pushrods. If you notice, the wear pattern is slightly on the outboard side of the valve tip. This is because I am still using the solid lifters in place of the hydraulic lifters for the checks. Once I put the engine together for the final time using the hydraulic lifters I will be putting a preload on the lifter. This basically means I will be tightening the rocker arm a small specific amount more which will push the lifter plunger down into the lifter body a small amount. Once I put that required preload on these lifters that will bring the rocker arm travel exactly where I want it.
Here is a good picture showing the combustion chambers on one of the cylinder heads. Look at the size of those valves!.... it's not going to be fuel efficient, that's for sure.
I put the other cylinder head on.
I set up the #2 cylinder valvetrain. I'm going to see what the wear pattern looks like on this side, just to double check. I didn't have to use the checking springs this time because I was using the actual pushrods and didn't have to worry about the spring pressure bending them like the pushrod checkers.
Wear pattern looks good on this side too. Once again, a tiny bit on the outside tip of the valve. But once the lifter preload is set this will be right in the middle. The preload will be somewhere in the ball park of 0.030"-0.060".
Next thing I did today was set up my dial indicator on the top of the valve retainer. I'm going to verify that my rocker arm ratio is actually 1.7. This means that the rocker arm actually opens the valves 1.7 times the lift of the lifter. During this check I'm also going to check the valve spring retainer to the valve seal clearance.
The dial indicator is set up on the valve spring retainer and set to zero.
The engine is turned over until max lift is achieved (the dial indicator stops and reverses direction at max lift). This number is recorded. At max lift I took a screw driver and pushed the spring down to take a look and verify the retainer to valve seal clearance. I did not need to use a feeler gauge here, I could tell that there was plenty of clearance here. It needed to be more then 0.070".
The picture below is kind of hard to actually see, but I was checking the distance between the top spring retainer to the valve seal on the bottom inside the spring.
Checking the intake side also
Here is max lift on the intake valve. It read 0.550" lift.
For the exhaust valve I got a max lift of 0.566". So in one of my previous posts I measured the lift at the actual lifters which was 0.319" on the intake and 0.330" on the exhaust. If you take each of those and times them by the rocker ratio that gives my a theoretical lift of 0.542" (intake) and 0.561" (exhaust). So my actual lift results are very close to theoretical lifts, only off by .008" (intake) and 0.005"(exhaust). I will chalk that up to accuracy errors on the instruments.
I'm getting pretty close to being done the pre-assembly checks, just a few more things to do.
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