Hey Cylinder heads guys- advice needed

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Mixing a roller rocker with a non roller would be worse than the existing tip height discrepancy. Way worse.
 
Mixing a roller rocker with a non roller would be worse than the existing tip height discrepancy. Way worse.
Hey Mike. Just wanna give you a public thanks for all your help with the wife’s Trick Flow heads I got from you.
Head bolts arrived safely and were up and running.

Now I’m on to fix the rear end issue.... LMAO!
It never gave ends....
 
Mixing a roller rocker with a non roller would be worse than the existing tip height discrepancy. Way worse.
I’m in talks right now with a member here on purchasing the correct iron rockers that match what I have. After getting the correct rockers I’ll be in contact with you Mike about getting the geometry correct.
As for the tip height difference, I’ll be taking the heads to the machine shop to get their opinion on the best way forward.
Thanks again to everyone who has contributed to this thread. I think there’s a lot of great information here that will be referenced in the future. The pictures alone are worth saving for anyone fooling around with W2s.
 
@B3RE
Hey Mike, would you be interested in taking a closer look at my W2s if I bring them out to you this week? A few things need addressed before I can move forward.
 
Are you sure about that? Adding shims under the spring to get the spring height correct should have no effect on spring rate. I understand that it doesn’t affect valve height but it won’t change the spring rate. Adding the shims is no different than having the valve seat higher, or “shallower” if you will.
Wrong wrong wrong. Kim
 
I’m in talks right now with a member here on purchasing the correct iron rockers that match what I have. After getting the correct rockers I’ll be in contact with you Mike about getting the geometry correct.
As for the tip height difference, I’ll be taking the heads to the machine shop to get their opinion on the best way forward.
Thanks again to everyone who has contributed to this thread. I think there’s a lot of great information here that will be referenced in the future. The pictures alone are worth saving for anyone fooling around with W2s.
The best way will be to start with a new valve if these have been ground. U may need new ex seats to raise the ex valves back up to factory specs. Kim
 
The spring rate is effected. To what degree depends on the springs rate to start with and then how much it is shimmed. Achieving the desired spring height, let’s use 2 inches, can use springs to compress the spring, seat work if there is t enough room.

At the correct spring height, the spring should have the manufactures closed pressure. If the spring height is less, the pressure goes up. If the spring height is to high, the pressure goes down.

If you had a spring pressure checker on hand, this is what you would see. It is no different on the checker to the head. This is why when people set up there springs installed height, they do it as perfect as possible. This becomes more and more critical as the springs pressures rate increases.

On a stock head and a Hyd cam, the pressures are low. Shimming the spring lower for more pressure (spring compressed more) will add a few pounds but on a very high performance engine, it may not be just a few pounds but a good bit more! This can be a huge problem if there is to much because it will grind on the cam into junk. Just the reverse, to tall of a height looses pressure and then the engine won’t RPM like it should because there is no valve control and the valve may bounce or just jump the ramps into valve float.

I’ll say it again, spring height and pressure are critical to the cam and engines performance. In a huge way! Big time. You can be off on 90 items, but the cam and valve train MUST be set up right. Failure to pay attention means a crap running low power engine.
 
The “spring rate” is the change in force over distance....... nothing more.

A particular spring will provide a given amount of force at a specific length.
How you arrive at that length does not matter.

If a spring has 150lbs of force at a length of 1.900”, and 350lbs of force at a length of 1.400”...... the “spring rate” is 400lbs/in.

Adding shims, different keepers, retainers, etc, does not change the spring rate.
The spring rate is designed into the spring.
 
Spring RATE is not affected by shims or anything else. The RATE in built into the spring, like any other spring. If you valve spring is 350 lbs/inch that means it takes 350 pounds to compress the spring 1 inch. You can shim it all you want, or not shim it at all and the RATE is still the same.

The seat and open pressures will change with shims but not the RATE.


EDIT: PRH tree’d me.
 
Mine in the mid up of pressure and rate terms misplaced.
I used rate instead of pressure.
My bad people, sorry, I was just trying to answer the question quickly and I didn’t think or proof read.
 
@B3RE
Hey Mike, would you be interested in taking a closer look at my W2s if I bring them out to you this week? A few things need addressed before I can move forward.
Yes, but I am pretty backed up at the moment. Give me a call to discuss.
 
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