WeathermanShawn

iTrader: (1)

Hi there.

First off, I have researched and used the search feature prior to asking the question.

I have read some interesting responses, but am interested in hearing the latest opinions and theories.

If I pick a cam that gives me the rights VE's, IVC, is there any inherent advantage or disadvantage in picking a cam that meets the desired DCR/Performance by just installing it "straight-up" (+0) advance?

I understand the concept of why so many cams are advanced, but are there any unique advantages to installing a cam say a 112 +2 vs 110 +0?

I realize this has been discussed and debated before. And, I am specifically referring to cam installation on higher CR Heads?

Anybody done it with success, and what was your thinking?

Not just a theoretical discussion, I have some specific goals in mind.

I know it is not the easiest concept one can answer, but I trust my fellow LS1Tech members will have some educated responses to share.

Thanks in advance..

..WeathermanShawn..

bad6as

iTrader: (17)

a 112+2 and a 110+0 will still have some differant ves

Old SStroker

Install it exactly where it was designed to be installed. Your cam designer should be very specific as to where it will work best. If he/she is not, get a new cam person. I'm not a cam designer, but the good ones I know told me what I posted above.

Ah, but you asked for opinions, not facts. You should get a lot of those. You may be assuming too much.

Good luck!

WeathermanShawn

iTrader: (1)

Thanks for the replies so far.

I'll always agree to follow the best advice. I'll take facts, opinions, etc.

Must be a few who found an advantage in just installing a cam "straight-up".

Slightly lower DCR, but I assume some difference in overlap between intake valve and exhaust valve might be to some advantage?

I know we are talking small differences, but any insight would be greatly appreciated.

Thanks.

..WeathermanShawn..

vettenuts

iTrader: (4)

You mention "higher compression heads" and should note that advancing will lower the PTV on the intake valve over cam installation on the "as designed" centerline. What ever you decide, make sure you measure your clearances. Too many guys seem to go by the edict "it clears". I still don't understand that statement.

Formulated

iTrader: (16)

Valve events are valve events... You have to know what you want. The camshaft itself will only fix the intake and exhaust lobes, and the phasing of those lobes with respect to each other (Exhaust centerline, intake centerline, and valve overlap). Beyond sourcing that camshaft, you then need to determine how you want the valve events phased with respect to crank / piston position. That's where degreeing the cam becomes important. I see a lot of people put cams in there cars that only know if the cam was installed advanced, retarded, or straight up; they can't tell you what the intake centerline is though. Don't make that mistake.

s346k

iTrader: (4)

adding advance/retard won't do as much as changing the lsa. determine your goals first, as always..

Patrick G

iTrader: (14)

In your example, the intake valve events are the same, but the exhaust valve events differ. By opening and closing the exhaust valve later, you add overlap and extend the power stroke before the exhaust valve opens. In some applications, this will increase torque, but it's really application specific.