I have a question about the crower cam I got part number 63442Z. If I enter the part number into crowers cam card tool I get the specs .006 and .008 Hot for the valve lash. When I go onto the catalog I find .006 and .008 cold? Can someone help me out here?

 

Set them COLD.

 

Crower has an issue with their cam cards not agreeing with the catalog. I ran into differing specs for my 62403-2's as well. It's the old rule - "if you come up with two different numbers, at least one of them is wrong", but I would recommend going with the cam card over the website.

Honda says set cold. Honda also says set them to .008" IN / .010" EX (for a stock cam, obviously). That makes me think Crower might actually want you to set clearance hot. It's less risky than setting them tighter than Honda wants, cold, then heating the thing up and burning an exhaust valve or something.

Sending a message to Crower is likely the best bet.

 

I had originally set them to stock specs and the car ran pretty well. I then changed it to the crower specs hot and the car is running like garbage now. I’m assuming it shouldn’t be adjusted hot, then again maybe I need my tune adjusted?

 

That's what I'm thinking. The 'cold' Crower specs are tighter than the Honda specs. Hot, there's almost no way .006"/.008" isn't too tight. It's gotta be a cold spec.

A touch loose won't harm anything other than robbing you out of a teeny amount of lift. Running them too tight can trash you top end and (as you've found out) make the engine run pretty poorly.

 

so if I’m theorizing this correctly when the engine heats up the clearances should get smaller due to metal expansion right? So for example setting the clearance hot would make the clearances looser once the engine cools off?

 

This is a really common misconception. The "hot" clearances are actually LARGER than they are cold, so if you set the valve lash hot, it gets too tight when cold... and that makes it run like crap when started cold. Now before anyone starts flaming me here, do us both a favor and test this yourself. Set your valve lash cold. Crank it up and warm the engine up past operating temperature. Shut it off and immediately pull the valve cover and check the valve lash on the same cylinder you tested cold. You will be surprised as to what you find... I know I was. I didn't believe it either... because it isn't logical... but it IS true.

 

Interesting. I’ve never checked them hot so I have no idea.

 

This is definitely true, I just got done re doing my valve lash cold and all the valves where too tight.
I set the clearances to .006 and .008 and it’s running like a champ. Thanks for the input!