I'm trying to figure out how much is a good amount to mill some 243's.

I'm trying to figure out how much would be good while keeping a few things in mind. I want to have the the ability to get a 230/230ish cam in there with no problem. Push rod length is also a consideration. I'd prefer it to be easy to pick the length and not have it end up in between the push rod lenghts (7.4 and 7.375 for example).

I don't know what the base circle of my cam is so if someone could chime in on that, I'd appreciate it. I don't even know what that measurement is. It's the TR 224 I have in there now though.

I'm thinking .015 mill would be good to bring my total "mill" to ~.025 since I'll be using a cometic gasket of .045. Here are my measurements:

stock gasket = .054 - .045 (cometic) = .009
.009 + .015 (mill) = .024

.024 - 7.4 = 7.376 (or close enough to 7.375 that I wouldn't worry about it)

.015 mill good? What do you think?

Thanks guys!

P.S. Search isn't being friendly so please don't refer me to it.

 

You have to take into account the (base circle difference)/2 on the longer side.

 

Ok...I just called TR and they said the base circle of my cam is about .030 smaller than stock. How does that factor in to my measurements?

 

Ok...I think I figured it out. Let me know what you guys think:

stock gasket = .054 - .045 (cometic) = .009
.009 + .021 (mill) = .030

.030 - 7.4 = 7.370

7.370 + .030 (b/c of the smaller base circle of the cam) = 7.400

I guess my answer is a .021 mill?

One other question is, would it be better to have slightly longer or shorter pushrods?

 

I believe base circle is measured as a diameter, not a radius, so you should add .015, not .030. Someone will have to double check me.

 

http://www.diamondracing.net/cocalc.htm