I've been trying to figure out a possible "rule of thumb" for overlap on cams that will pass smog. I've been told that the more negative overlap the better for passing but it also depends on the size of the cam so I have 6 possible grinds in mind. Let me know what you think would have the easiest time passing smog while making the most useable power. I have the same lift on all the cams as a point of reference, it is subject to change depending on what cam will work th best.

216/216 .585/.585 110 has -4* overlap
216/216 .585/.585 112 has -8* overlap
218/218 .585/.585 110 has -2* overlap
218/218 .585/.585 112 has -6* overlap
220/220 .585/.585 110 has 0* overlap
220/220 .585/.585 112 has -4* overlap

I'm hoping anyone with knowledge on cams that can pass smog in Cali can help or just anyone that knows cams in general.

Lance or Sport Side if I could get either of your opinions on this also that would be great. Thanks to anyone that can help me.

 

I would call Synergy motorsports. They would probably be able to advise you in which direction to go.

 

Your at the point where you just need to drop the hammer and pick a cam... I mean, that's even a lot of cams to pick from but the negliable difference between any of them isn't really worth the hassle. You could really start twisting things if you took each cam and divided them up into sub categories of +2* of advance, +4* of advance. That would take those 6 cams and make them into 18 total cams to choose from.

Your first one, the 216/216-110 should have -4* of overlap @ .050'' by the way. They all look fine, but cam #2 and #4 are going to be your best bet of 'playing it safe'.

How often do they have smog checks? Just go ***** out and swap in your stock cam before smog checks. Not too hard. The bitch is valve springs and you'll only have to that on the first install.

 

Mind you, this was on an LS2 but, I have seen 228/232 on a 112 pass smog. But on you 5.3L I would cap the limit at 224 at 114, any wider on the duration, or any narrower on the LSA would start to push it. On those cams, why the 110-112? Those should pass on a good tune, obviously with cats.
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George P. Lara: 2001 Camaro SS #0391
HPTuners for '98-'02 F-Bodies & '99-'02 Trucks



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1998 Camaro Z28: 9.94 @ 137, 1.45

 

smog checks are every 2 years. Yeah I realized that I messed up the math on the first cam. I have a smog check due this year so I think I will wait till after I get it done to swap it. Then just got with something that I can get the most out of and keep the stock one for the next test.

 

Less overlap=more "under the curve" power as far as I can tell from various dynos on different cams with small LSAs. As a plus they sound great .

I think I've narrowed it down to a 218/218 .590/.590 110 or a 220/220 .590/.590 110 and I will just reswap the stock cam in when it comes time for the next test in 2 years.

 

This is what I've heard also.



Side note: I hope you guys that live within reach make it to Sacramento on the 17th!

 

Im hoping to make it but we will see.