Visceral

iTrader: (1)

Hey all,

I want to get some discussion going on what has worked for people who have found their valvetrain quieter than they were expecting. Many of us drive Corvettes, and want the car to sound as refined as when we bought it, or we drive F-bodies and dont want the valvetrain to be louder than the exhaust.

Several folks have mentioned Yella Terra Rockers. If you have done Yella Terras, how much did they quiet the valvetrain? Was it very noticable in the car, or just in front of the engine? Have people who have done the street version of the Jesels noticed the same? I remember the Crane 1.8 arms seemed to make my whole setup louder.

Some folks have had luck with some cams being quieter than others. Is there a cam you have put in that has been surpisingly quiet despite a serious ramp rate?

Some folks might have other ideas or practices, like slightly more preload, or different size valves.

In talking "back in the day" (99 or so) I recall that alot of engine builders said that larger valves often made the valvetrain noisier than a particular cam. I thought alot about that until I heard SW's 422 Solid Roller, which had a valvetrain as quiet as a stock car. (I still havent figured that one out to this day).

What do you think can be done to quiet the valvetrain after a big cam, and why do you think it works?

Chris
(who had forgotten how loud these things were after 2 or so years )

Warbird

I have found that the type of headers used seems to have an impact as well. They seem to pick up and amplify the added noise even more, especially long tubes. My Grots were loud as hell and when I removed them a lot of noise went away.

A lot of the noise seems to be the luck of the draw. I have seen cars with identical mods, one was noisy the other quiet. The aluminum block and heads doesn't help much either, it acts like a damn echo chamber. Cam choice will make a diference, single pattern cams tend to be quieter than split patterns, likely because of the natural even, pulsing that tends to cancel some of the valvetrain noise. Last but not least, I have heard some pretty noisy full roller rockers as well, they are expensive and may not cure it.

I think if you have noise there are things you can do to lessen it, but you can spend a ton of money tracking it down and not fix it, screwing up your combo in the process.

I just learned to live with it. A loud exhaust can drown it out

DaleMX

iTrader: (4)

Personally I love the sound. It reminds me of my old big block solid lifter (huge PITA). Not exactly the same, but close. I agree that headers amplify the sound. Cast Iron exhaust is good for keeping it quiet. Maybe heat tape can help (although it will eat up a set of headers quicker than normal).

The Yella Terra's have alot of mass to them and I imagine they absorb some of the racket from the valve slamming shut.

BergerMan

I never ran my stock rockers with my H/C so I really can't compare the difference. Rockers are not the only thing that add valvetrain noise. There are quite a few things that add noise to the engine compartment that most guys don't think about.
Big cams and stiff springs really slam the valves closed making a clicking sound.
Adding headers really amplifies noise from valves closing.
Injector pulse noise - especially after tuning.

I hear a little clicking (sewing machine sound) at idle and a little clicking at about 2250rpm but other than that it sounds fine to me.

VINCE

iTrader: (1)

I agree with BergerMan.. These sounds are perfectly normal. You want to quiet it down. Put the stock manifolds back on I have yet to hear a quiet car with a big cam and headers. Even one with yella terra on..

Cal

iTrader: (1)

I have a TR224, 918's, Yella Terra's, comp Ti retainers, TR pushrods, 5/8 turn of preload and stock cast exhaust manifolds. Valvetrain sounds exactly like it did stock, but I couldn't tell you why!

In the past I owned a '67 Firebird with a big-block 389 running a 270 @50 thou with flat tappet solid lifter cam and headers. That thing had the loudest valvetrain noise I've ever heard! Sounded like a cross between a Singer sewing machine and a hay-bailer!

MyLS1Hauls

iTrader: (2)

Obviously the valvetrain is going to be noisier with aftermarket cams/springs, but they dont all seem to be exactly the same. When I installed my Comp 216/216 .538" lift cam with 915 springs, the car sounded like a sewing machine. I was using stock pushrods. I then installed a TR220 with 918s and chromoly pushrods. The car sounded exactly the same...these were both with manifolds still on the car. I then put headers on and really noticed no added valvetrain noise...typical header tick, but thats all. I then heard a buddy's XE-R 228/236 cam and it was so freakin noisy I couldnt believe it. He's running MTI S2 heads. I then installed an XE-R 228/228 and it seems no noisier than my TR220 cam. I would imagine his is noisier due to the larger valves. Also, another buddy has my old TR220 cam in his truck and it sounds like a sewing machine too. I personally have never heard an LS1 with an aftermarket cam that sounded like stock. They have all been noisy, just to varying degrees.

Cal

iTrader: (1)

I know it's crazy, but mine sounds stock! Unless my hearing is just shot, LOL! But I think having enough lifter preload has a lot to do with it also.

Visceral

iTrader: (1)

I cant really believe that tough springs make for a louder valvetrain... I mean if you think about it the valve should be following the lobe... if it isnt, the valve would slam down on the seat even more abruptly.

I could believe the valve size or seat design could effect the sound a bit.

The cam is the logical culprit for sure. But as we've seen, some people have different results with the same cam.

In theory, the header tube could amplify the exhaust valve sound... more so than manifolds.

Several people have said that the Yella Terras quieted the valvetrain alot. I wonder how that works. Theories?

I really would like my valvetrain to be alot more quiet. Im trying to make this Camaro refined. Imagine!

chris

Visceral

iTrader: (1)

Interestingly I was able to mess with the crane rockers when I had done a coil pack relocation. I was able to vary the preload while the car was running. Once you had the preload within normal range, more preload made no difference.

Interestingly, some rockers/springs/valves made far more noise than their neighbors, no matter what the preload. That was sort of annoying to try and reason or troubleshoot.

chris

Cal

iTrader: (1)

Back in the early 80's, I was running a '67 Firebird with the setup I described in the post above. Eventially I got sick of the driveability issues with the big solid lifter cam, and replaced it with a smaller one, but retained the headers. At this point all of the valvetrain noise ceased and it sounded like any other stock motor. The lift on the "big" cam was only 0.530 lift, but the duration was 320 advertised, which I believe is around 270 @ 50 thou. Heads still had the stock valves.

I believe LS1 cams with high lift and a relatively short duration are usually pretty noisey; at one point I was going to get a Comp cams 218/0.563, but everyone I talked to with that cam had a huge amount of noise. I lot of people with fast ramp cams like the XER report a lot of valvetrain noise also.

Brian2001SS

iTrader: (1)

Mine didn't increase much in noise after my TTS header install (over the stock manifolds)

My Yela Terra's w/ shims (1/8 turn preload) was very loud.

Removed shims (1 full plus 1/8 turn preload) car is as quiet as its been. Quiet stock, can hear it at 2000-3000 rpm. Wife even noticed a big difference in noise with the more preload. Course stock preload (stock rockers)is even more, but it was a little louder. So the Yella's do quiet it down some.

niphilli

My Friends '99 Trans am (TR224 cam, hardened pushrods, comp 918s, ti retainers & mac mid lengths) makes no-more valvetrain noise than my stock Z does. I think the biggest contributing factor to valvetrain noise is the lift of the cam, ie) how much the springs bind. I have not experienced the thrill of a solid roller LSx based engine though and if SWs car was mouse quiet I guess that shoots my theory to the ******* .

Dope

iTrader: (2)

Oddly enough, I was just thinking about this recently.

I had a 2000 SS with longtubes but an internally stock motor. With the hood open the engine was pretty loud.

I now have a 98 SS with just minor bolt ons, no headers or anything. It's somewhere between the 2000 SS with manifolds and with headers.

I have a 99 FRC vette as well, with ported heads, T1 cam, longtubes, stock rockers, comp 918s, etc, and it is QUIETER THAN ALL THE REST.

Don't ask me. The old T1s were pretty slow ramp rates, so maybe that's why it's quiet? Don't know what else to say.

Dope

Bearcat Steve

Does the quality level of the lifters have anything to do with valvetrain noise?

VINCE

iTrader: (1)

Just a FYI.. The TR224 cam is not big.. The size of the cam does matter when it comes to noise. I have had 5 cams in my car and I have noticed the bigger the cam, the more noise. The ramp rates matter as well.. My old Lunati T1 had slow ramp rates and sound like my current FM-9 cam. I would love to quiet my car down, but right now I love that old muscle car sound..

JoSeY

10/40 royal purple if you live in a hotter climate....No noise almost. Rev dual valve springs (The BIG ones, X1 cam, blah blah) most you hear under my hood is injector cycling...oh..and a miss.... ;-)

malibu350

I think it's just people's different combinations.....my friend went with a new setup and he had the crane 1.8's with H/C and it was loud and he complained about it all the time. Tried messing w/ the preload and readjusting them quite a few times....I took his combo H/C and rockers and installed everything on my car....the only thing that I changed was I got shorter push rods and put the ASA cam in which I believe was bigger than the cam that he was running....after we fired it up he was pissed because the rockers were quiter in my car....I mean they make a quiet sewing machine sound but nothing too abnoxious like people are describing above....He thought he may have been due to the fact that I got shorter pushrods than he was running..so who knows

Jorday

I agree that the bigger cams seem to make more noise. I've got a really loud exhaust now so I can't hear anything, anyway. LOL

Jordan

99 Black Bird T/A

iTrader: (4)

I find it sort of hard to sort out exactly what is making the noise sometimes.

fuel injectors are noisy
air check valves are noisy
valve train is noisy

Restrictor plates for the air checks can help a little. Shimming the rockers so they all have the same number of turns to tighten to 22 lbs might help a tad.

But like very one else I think it's the cams, the stiffer pushrods, bigger valves etc it all usually adds up to more noise.