Where to degree my cam?
Via your description of straight up, If I'm understanding you correctly, you would suggest he might install this cam at 102 ICL. Yes?
Yes if it is street engine only, as said.
The following is all to explain my viewpoint.....
1. I can't see where the ground-in advance has ANYTHING to do with where one decides to put the ICL. The manufacturers just do it IMHO to make the cam peppier in a stock setup so the customers won't be AS likely to call it a crappy cam when they just shove it in dot-to-dot with a worn chain and low CR pistons LOL
2. The ICL decision is all in the application as well stated earlier. That is why I distinguished between drag race and other uses. One thing to keep in mind that not only does the torque RPM range tend to go lower with cam advance but the min to max RPM RATIO for good torque improves. As an easy to see example:
- If the torque range is 3000-6000; the min/max RPM ratio is 2:1.
- Move it down to 2000-5000, and the min/max RPM ratio is 2.5:1. Same total range, but a better min/max RPM ratio.
That means in racing venues like road race and rally, you are not as likely to 'fall off' the torque curve as you manage the gears in various turns. I rally, and I want as close to a
3:1 usable torque RPM ratio as I can get. A 2:1 RPM ratio really SUCKS for rallying; I tried it when I was younger and was just doing the standard big cam stuff that everyone else was doing!
3. IF this case is for the street only, why not? The SCR is here not gawdawfully high and the DCR will be around 7.8/7.9 with the ICL at 102. The cam lift is not very high, and nothing will crash in the valves with these pistons. It'll definitely help low end torque to improve response and driveability on the street.
IMHO 102 is not a radical ICL in this setup. I went 106 on a 112 LSA with a true 10:1 SCR for street (vs the 107 ICL ground in timing) of the Crane cam we used to get the DCR to the 8.2 range, and thought about more (but chickened out on the DCR LOL). The OP won't have that high a DCR at 102. If there is a factor, like another cam timing event, to consider that I am missing, then that would be good to understand.
BTW, 102 is easy to get with this cam, with the +4 advance crank sprocket position commonly found on multi-keyway sprockets. So that is a coincidental reason to use that number.
4. I think everyone here does not do cam advance like this for a drag race engines. More peak HP at a higher peak RPM for better ET's makes sense, bu that will reduce the usable RPM range: higher TC stalls, and slipping the clutch more get around that problem.
