Has anyone ever been able to confirm cam specs from Crower? There are discrepancies between their cam cards and the catalog specs, and it makes a significant difference in the numbers that I'm trying to crunch:



EGT's can be combatted by adding timing in the affected cells, especially if the load is low.








Instinct tells me to trust the cam card, but I have a problem with the fact that it specs a hot valve clearance, which is the opposite of every Honda setup I've ever worked with. The other problem is the obvious old adage, "If you have two different numbers, at least one of them is wrong."


I emailed them a couple of weeks ago and haven't heard anything back.

 

The hot clearance thing must be a misprint. I, like you, have never seen a lash spec given out as 'Hot'. I think the main reason they're not given out as hot is because what is 'Hot'? just off the track hot or after a little idle time hot??

I normally use the .050" method to find the centerlines, strange that they only give an intake cam center and not the exhaust cam center....

 

Setting the lash at operating temperature is normal for some styles, just not for a Honda. I'm sure that part is a typo. I'm mostly concerned with the discrepancies between LSA and lift numbers. That keeps me from properly calculating some numbers, specifically intkae valve closing (which gets me to my dynamic CR).

Mostly, I just want to know which number is right. I hate making assumptions.

 

The "Hot" valve lash number may be given because of the bucket/rocker type assembly used in the LS head... but it is inconsequential with respect to degreeing the cams because this process MUST be done "cold"... and you set the valve lash to .000" anyway. Focus on the open and close events and degree from Crower's given specs. My personal experience with the Crower stuff places the close events within one degree +/- of advertised when the open event is spot on and zero lash is attained, and the peak lift will be +/- .003".

 

Yep. I understand all of that. I'm not concerned about the lash. I'm confident that it's wrong on the card and right everywhere else. I'm not terribly concerned about the 1* of LSA, or the .002" of lift... but the significant difference in advertised duration completely F's the dynamic CR calculations. Check it again... You're looking at 12* and 13* difference. That's huge when finding IVCA.

I know that these cams will work in my application, but that's not the point. I might have to see if the cam guy at my work can map them for me, but that requires setting up a fixture or preferably finding a spare LS head to use as a fixture. We'll see what happens when I have them back in my possession.

 

I made a ghetto profile station for doing D-series cam stuff. I used a dial indicator, degree wheel, old cam gear, and Excel. It worked really well just took some time.