Say 2 large camshafts (we'll use the G5X2, 232* I, 240* E), one on a 112 lsa and one on a 114 lsa. How much more "lope" would the 112 have vs the 114? Its still a pretty big cam, but would the 114 smooth it out alot, or not that much?

Also, when a cam spec (LSA) is given as 112 + 4 or 114 + 4, I know that means that 4 degrees of advance is ground into the cam. Practically speaking, what does that do? Does it affect idle, rpm peak, P to V clearance, etc? Or does it just have to do with the valvetrain events (valves opening and closing at a certain point)?


I guess what I'm asking is what would be the practical differences between a G5X2 with a 114 lsa, and a G5X2 with a 112 LSA?

Thanks, Shawn

 

Shawn, how does all of the above grab ya? Or more accurately, whenever you change the valve timing, it is going to affect to one degree or another - idle, peak torque/hp, piston-valve clearance, vacuum, etc ad nauseum.

In a general sense, advancing the cam will make the valve events happen later, which has the tendency to build more torque and lessen the power. For example, if your intake lobe has a center point of 106 degrees BTDC, advancing the cam will give you an effective IVC of 104 degrees BTDC - thus moving the opening and closing events two degrees. Conversely, retarding the timing events favors greater power output and less torque. Using the example above, retarding the cam 2 degrees will give you an effective IVC of 108 degrees thus opening and closing the valves 2 degrees sooner.

That should help as long as I didnt do a dyslexia thing to the chain of events. In any case, I'm sure more knowledgable folks will reply and correct me if I mistated the facts.

 

ttt

 

as far as the advance being ground in. the 114 + 4 would have 4 degrees advance if i'm reading that right. which would imply its ground with a 110* intake center line (icl) the 112 + 4 would have a 108* icl. with older engines like the first gen sbc you could play around with the cam timing and see if you could eek some more power out of it. but if you do that today i hear it messes with the fuel injector pulse timing. so cams come with advance ground in. to answer another question advancing decreases piston to valve clearance. minotaur15 pretty much got the effects of what avd or ret do so i wont go back over that. imho along with a couple other guys here the "right" cam for your engine will make best power installed straight up. advance is sort of a "crutch" cam companies use because people tend to go a tad large with thier cam choices and the adv. being ground in is an attempt to restore a "soggy" bottom end. hope that helps. if i've made any mistakes others will chime in.... its been a long day.

 

Who sells that G5X2 cam?
I was personally looking for something close to tose specs. Perhaps 234-240, and I was also looking at 232-240 as another possibility.
Thanks.
-Goose

 

the g5x2 is an ls1 cam...but lg motorsports sells it. lou giglioti i think his name is.

 

I think the 114 would definitely take some of the chop out of it.

My 242/242//114 idled better than my 244/244/112 and we spent a lot more time getting the latter to idle well.