yeah i had no clue about the diff between ICL and LSA but i guess now i have a better idea

 

jeez! he just asked what time it is, dont build him a clock.......

j/k!! very informative

 

Wow, you people are all over the place!!!!

Wrong!

If a cam ground on a 112 ICL has a LSA of 112. it might have 0* advanced built in, but you would need the cam card to know...

IF THIS CAM WAS ADVANCED 4*, it would still have a LSA of 112 YOU CAN'T CHANGE THAT!!!! but its ICL would then be 108* 4* SOONER(ADVANCED)

 

Ok my cam card says LSA is 112+4, so that means my ICL is 108? no?

 

Not necisarily, your card should tell you the recomended installed ICL, try to find it...or post a pic of your card.

 

This is all i have. I dont think its the full card. Its on the outside of the box.

I bought it from Brand new from a member on here.

 

Ya, thats not the card. the card will give you all of the events, intake open, intake close, exhaust open, exhaust close, ICL LSA etc etc. call them, give them the grind number and have them fax or email you the card so that you can instal it how it was intended. I had a cam in my hot rod that i installed with the gear 4* adv. when i put the dial indicator on it it was still 8* retarded... so you need to know, from the card, the recommended installed ICL or you could leave a lot of power on the table... after putting my cam where it was supposed to be, i gained 37 TQ...

 

Please give me any example of a cam where the LSA and ICL are equal, and yet the cam has ground in advance, so I can try to figure this one out.

LSA = (ICL + ECL)/2
LSA - ICL = ADV

Given those two formulae, I don't see how you can have advance on a 112ICL and have a 112LSA.

Look at it this way:
1) LSA = (ICL + ECL)/2
2) LSA = ICL/2 + ECL/2
3) LSA - ICL/2 = ECL/2
4) 2*LSA - ICL = ECL
5) 2*112 - 112 = 112 -- that's straight up, right there, yeah?

Do you mean the intake events are really wide and so the ICL is advanced to be at 112? I don't think that matters -- it's still straight up, isn't it?

Sigh. You're right (sort of -- see ** below). It IS expressed as lsa+advance on a cam card I just looked at... which just makes it all more confusing to me. All LSA represent is the angle between the intake center line and the exhaust center line as ground--

LSA = (ICL + ECL)/2
LSA - ICL = ADV

All cams are spec'd on a certain ICL that they are recommended to be installed on (and this is the ICL used in the second formula above, *not* the ICL after you've advanced the entire cam on installation).

So, as you say above, that 112+4 is a 108ICL 112LSA cam rather than the 112ICL 116LSA cam I talked about in my first post here.

LSA is not a cam designer's spec, it's a cam grinder's spec. Many of us have been muttering for years that we should not discuss LSA at all (instead we should be talking valve events, but that's way too complicated and icky).

** BTW, I never said you can change the LSA, nor implied it. What I said was that a 112ICL cam on a 116LSA had 4* advance, just like a 108ICL 112LSA cam also had 4* advance. Later, I said 112+4 was a 112 ICL 116LSA cam and I was wrong there and 04Crew was right -- I was the one with naming convention reversed.

 

I never meant to imply that YOU thought that you could change it and your correct in all that you posted above, i just used your line as a quote. All i was getting at is that you need to read the cam card cuz not all cam grinder list it as a 112 +4 etc. you need to see the card to find out how much if any adv. there is, some are 0*, 2* 4* and then you have ones that list +2, +4 etc. sorry to spot you out like that. you should read this whole thread from start to finish it is hilarious and frustrating at the same time to watch people swith ICL and LSA back and forth and talk about advancing a cam and getting different LSA's etc.

 

man didnt think this thread would be such a big deal jeez so whos right and whos wrong