Quick question about ATC 200 Heads and Cams

[ATCR250R]

Ok, I think i finally have it figured out. Correct me if I am wrong, any 185/200 head has exactly the same fin size, valves, ports, etc. but when comparing cylinders 200X have bigger fins, but are otherwise the same. Also how can I tell a 200X camshaft from a auto clutch 200 or 185 cam? The reason I ask is my motors were all switched around when I got them and I want to make sure I am running the X cam. Thanks for any help!

[Levithan]

Yea, i just did an Auto X project. You will definitely want the 200x cyllinder and head, it wil cool alot faster, especially if you have a higher compression piston. As far as the cam, i believe that they're all the same..... ? Im not sure about that though, dont take my advice, can anyone else clarify this? i used the 200x cam myself though. Anyways, good luck there man -)

[Howard]

in the service manual does it not give cam specs. ? seems like it would to let you know the tolorences as if it's still useable or not. need a gauge it.

this is what i ahve for a 84-85 200M. spec sheet.

[ATCR250R]

I thought I heard sometwhere the cam durations are different, not the lifts. I am not positive. I thought all heads were the same fin size, just not the cylinders. I measured all my heads and they are about the same, if different at all.