therobman

iTrader: (39)

i have a cut out only thing i hear is cam lope. you cant quiet it down plain and simple its a noisy motor alot of people complain its not a luxury car buy any means buy a cheap dd

Ice78Transam

iTrader: (1)

Headers do a lot to amplify the exhaust valve noise, the metal is much thinner than the cast stock pieces. Very common. This becomes even more pronounced when a cam with quick ramp speeds is installed along with beefier springs. Its a trade off, power makes noise.

RPM WS6

iTrader: (3)

This is exactly correct.

As a matter of fact, those with a keen ear will even notice more engine noise with a stock '98/'99 motor and manifolds, as they were rolled stainless vs a thick chunk of cast iron for the '00+ cars.

01ssreda4

iTrader: (96)

Im only speaking from personal experience I have had. My car was noisy but it was the AIR pump running. After that was deleted it was quiet. My car was quiet with a TR224, 7.400 pushrods, and headers. Never any valvetrain noise. All the other LSs I have worked on have been quiet too. Maybe I have been lucky, I have always thought the LS motors got a bad wrap for being noisy.

SOMbitch

iTrader: (8)

The Comp lifters have very stict tolerances to preload and IIRC it is .010 or .015 warm. LS7 lifters are much more forgiving and .060-.090 is spec. Recheck your preload.

FWIW I have found the lower range of preload to be quieter than the upper ranges on LS7 lifters....

86atc250r

iTrader: (1)

FWIW...

My LS1 is a bit noisier than I'd like, but I wouldn't consider it bad by any means, just louder than I'd like - it's cammed, springed & LT'd, but I haven't yet measured the pushrods.

This fall, I went to a corvette event - probably close to 1000 late model cars in attendance. Lots of big cammed LS engines.

It's interesting that so many are saying you have to live with it, nothing can be done, etc... I made a point to carefully listen to every car with a cam and heard no noticeable valve-train noise from the vast majority of them - even ones with obviously far more cam than I have & ones spinning up a lot tighter than I can. Leads me to believe something, in fact, can be done. I'll be tearing into mine this winter, first order of business, check the pushrod length....

RPM WS6

iTrader: (3)

Good luck with your quest for quietness. But keep in mind, there are acceptable machining tolerance ranges for every part inside your engine. This is why no two engines are 100% exactly the same, nor will the same setup dyno the same in two different cars. Even two stock cars will run and dyno slightly different. Point being, you might have a part or two within the top end of your motor that's on the slightly loose end of the acceptable tolerance spectrum, and you might end up replacing it with another part that is still within spec but also slightly loose. In theroy, you might replace an endless number of parts in this manner and never acheive your goal.

Trying to chase down a minor amount of extra valvetrain noise after a cam swap just because your buddy's car doesn't sound exactly the same, would be like trying to chase down a few more horsepower just because your buddy's car makes 5 more RWHP with the same package.

86atc250r

iTrader: (1)

I agree that pursuing very minor differences is an exercise in futility -- While I do not feel my noise is major like an obvious mechanical issue or even a single lifter with a tolerance problem, I do not believe it's trivial either.

My problem is the engine is nice and quiet cold. As it gets hot and has been driven a while, the noise begins to appear. If I'm in a confined area (like a road with a concrete divider or in traffic with a car next to me) I can hear it reflecting off hard surfaces. This tells me it is audible not only from inside the car, but outside as well.

My engine otherwise seems very tight and in great shape - about 70k miles, all stock 2002 model w/LS6 block until about 1000 miles ago when it was swapped into an older vette & the cam was installed. It gives me no reason to believe that any of it's tolerances (other than possibly ones I've modified by installing a cam & springs) are out of whack.

That all said, I have a strong feeling my engine can be improved by careful inspection of valvetrain tolerances and/or possibly a change to a lifter better capable of handing my increased spring pressure. The simple fact that I walked amongst literally hundreds of LS engines (many modified to a much higher level than my own) for two days, and carefully listened to all within earshot for the express purpose of comparing to my own and can't clearly remember even one with a significant amount of noise leads me to believe that mine likely can be improved upon. The numbers are with me, if something simply can't be done, I believe I would have heard a lot more engines sounding like mine. If not I'll at least have the satisfaction of knowing I've done all I can to make things right.

RPM WS6

iTrader: (3)

I do get what you're saying. Beleive me, I'm a stickler for details and I notice everything that is wrong, strange, or even the slightest bit off about any one of my cars...or even anyone else's cars. But sometimes it's just not worth chasing. Obviously, only you can decide if your particular noise is loud enough to warrant a comprehensive valvetrain inspection, and frankly I can't blame you for wanting perfection. I just know first hand how hard it is to attain perfection with a modded (or even stock) car.

Both my '98 and '02 LS1s have their own individual sounds. With the '98, you can hear a bit more of the engine mechanics under load due to the thinner walled manifolds than was used on '00+. I've owned and driven several stock '98-'99 cars and they all have that sound, to some degree (no two cars being *exactly* alike), under certain conditions. If you listen under the hood while working the throttle just right, you can clearly hear it coming from within the manifolds, as they are built much like a shorty header. My '02 car (with cast iron manifolds) does not make this sound at all.

My '02 car has the infamous LS1 piston slap, a pretty bad case in fact. But it's been the same for 96,000 miles without any ill side effects. The motor burns NO oil, makes great oil pressure, and runs very strong for a stock engine. Both my '98 and my '02 have stock engines, but one has piston slap and the other does not. The "slapper" is still tight enough to not burn a drop of oil though, likely making this a case of "within factory tolerance, but on the loose end". I could rebuild the motor trying to get rid of the sound, but it just doesn't seem worth it to me because I'd gain no improvement in power or driveability. As far as longevity, I fully expect this engine to go for another 96k miles without a rebuild if I let it.

As far as your motor being totally quiet prior to the cam swap, I would again chalk that up to the possibility of machining variances either within the new parts you installed, or in how they interact with the factory parts that were retained.

Nothing wrong with double checking your work, just don't be too disappointed if you can't get it exactly as quiet as the next guy. These motors are in fact prone to being noisey, so if you're lucky enough to get a quiet one, don't always expect it to stay quiet once you do a cam swap.

02WS6SSZ71

iTrader: (20)

I'm no expert on top ends, but no one has mentioned rockers...so many people go cam only and run stock rockers, which I believe are only "supposed" to handle .550 lift before they start injuring valve guides. Who has gone roller rockers, and does this help quiet down the top end after a cam swap?

01ssreda4

iTrader: (96)

Right, that point was argued in a magazine article I believe. It quite simply was proven wrong before that article was even published. There are too many people running over .550 every single day for long periods with no issues.

Juicy J

iTrader: (5)

Were these cars mostly Gen III engines, Gen IV engines, or a mix. Gen III are the noisier ones.

99FormulaM6r

iTrader: (2)

It won't make a huge difference, but switching from 0w or 5w-30 to 10w-30 can help quiet your engine down.