Thinking of going with LMI's over my LMII's but I was wondering how much louder a cam will make the car. I've heard people say that it makes it significantly louder, so I was holding off before doing a louder exhaust and then thinking it's way too loud. The cam will be a G5X3 on a 114LSA. Car has LT's with hi-flow cats. Thanks folks!

 

Idle will be WAY louder. The rest of the rpm range will be slightly louder as well, but not as big of a difference as when idling.

 

yeah id say about the same thing when i went from stock to a 233/239 114 lsa cam idle was alot louder and driving through the rpms was a little louder but not too much until you romp on it then its wicked loud. But just fyi before my heads and cam i never got pulled over for loud exh now i do all the time and i have full exh cats and muffler.

 

check my videos for an idea the tire view burnout is before the cam, then listen to the am fire up vid to get an idea

 

It also depends on what cam you are using. As cams with larger LSA (114+) will bleed off some of the cyl static compression and as compared to a cam with a smaller LSA (110-112) cause a louder exhaust sound or tone.

Compression ratio and duration also come into play. I changed my cam a few times in my 84' z28 to a small one (and larger one) and lost a few DB's in noise.

But in general.. bigger cam, louder noise.. !

 

what do you mean? when your cars sitting idle, you can hear the cam the most.. its going to be probably super loud with a loud mouth set up.. my TDs can get scary loud

 

The G5X3 will give you around 10-14° of overlap ( I don't know the exact duration, but I believe it is around 242/240ish). It is not that it is louder, but the fact that there are small quiet spots that give it that inconsistent idle note. That quiet spot is known as a valve overlap. That is why it seems louder. Click the true dual link in my sig. I have a 16° overlap'd cam on a 115. It is all the valve events that determine the lope. Simple math really. Just about anything over 5° will have some chop to it.

Here is my cam for example: 244/248 .595/.595 115+2

Duration + Duration = Sum of Duration
Take that sum and divide it by 2.
Multiply the LSA by 2 = XXX
Take that number and subtract the LSA x 2 from it.
The final number is your overlap. Be it positive or negative.

244 + 248 = 492
492 divided by 2 = 246
115 x 2 = 230
246 - 230 = 16

16 is the valve overlap.

 

That's what i said, the biggest difference in sound is at idle.....not as big of a difference throughout the rest of the rpm range.