corvettenutz

I am looking to get a cam. The car runs awesome IMO and Im not really looking for more power just GOT TO GET THIS LS7 VALVE TRAIN QUIETER. Thanks In advance. Car is a all stock 08 with headers and small cats. Heads have been done by ahp.

BigVette427

I like my custom TSP cam with .635"/.635" lobes. TSP cams are specifically designed for LS motors and in combination with my other mods, went a long way into nearly eliminating the common LS sewing machine noise. Going custom, I was able to select my own duration, LSA, and ICL, but I only had two choices of lobes. For me, the .635"/.635" were perfect. I live just a few miles away from TSP and was able to tour their shop and view their Landis CNC cam grinder, and that went a long way for me towards selecting them for my cam. AHP's 116 cam also has valvetrain friendly lobes that will help quiet your overall valvetrain as well, while providing a nice gain throughout the entire RPM band.

However, if you really aren't interested in more power, you just want a more valvetrain friendly cam with superior lobes, (I suggest you also pop the extra $50 for the 8620 cam core,) than I would suggest you consider an LSA slightly higher than 116.

Any of Cam Motions Stage 1-3 LS7 cams on a slightly larger LSA (stock LS7 cam is 120) would fit the bill nicely. They use .630"/.612" lobes. I love the way my 116 cam sounds but there is a slight lope to the idle with the NPP open, and a discerning individual can pick that up. Close the NPP though and you'd almost never know. In full disclosure, it drives very easy, almost easier than stock given the slightly higher idle speed (~ 800 rpm). Smooth and powerful.

EPS also has a 222/242 cam for rectangular port heads on a 117 LSA, with lifts measured on a 1.7 rocker at .597"/.605" which equates on a 1.8 rocker to .632"/.641".

Must_Have_Z

Replacing your cam simply to "quiet your valve train" makes no sense, especially if you don't want more power or to lose stock drivability.

If you want to quiet down your valve train, get a louder exhaust or turn the radio up.

polyol

All LS7 motors sound like sewing machines, regardless of the cam.

Lorenzo Serra

"Replacing your cam simply to "quiet your valve train" makes no sense, especially if you don't want more power or to lose stock drivability."

Indeed; if your valve train is louder than usual I'd suggest updating your valves guides to proven parts such as the MS90 guides and even more effective I'd update your rockers to CHE rockers.

hotrod03

Heads ported and polished, mill the Heads .020 PSI 1511 springs, TI retainers. Everything else is stock. Sounds and drives wonderful.

BigVette427

The decision to swap cams while I had my heads off was as much for durability and my desire to have a quiet and easy valvetrain as it was anything to do with any desire to have more power. One of those Cam Motion cams on a 117 or 118 LSA with lifts just slightly higher than stock in the low 600's, especially on an 8620 cam core, is far superior camshaft than the stock GM LS7 cam. It's not just the "sound" of the valvetrain that is significant here, the diminished sewing machine sound is the result of a valvetrain that is easier (less stress) overall on the entire valvetrain.

EPS talks about the importance of LS friendly camshaft lobes. TSP and Cam Motion are also big on this.
http://www.engpwrsys.com/tech-notes/cam-design.html

With the combination of my lifters, cam lobes, valve guides, and even trunnion kit, the typical LS sewing machine noise has been all but virtually eliminated on my motor. I would argue it's the way the LS7 should have been from the factory, but that's also part of the beauty in it for me, it purrs like a kitten and roars like a lion when you put your foot in it.

Lorenzo Serra

That's a solid answer! I'll add that aftermarket long tube headers may add a little bit to the sewing machine sound.

Unreal

This. Nothing will be quieter than a stock cam.

BigVette427

Nothing may idle quite like the stock cam, but you most certainly can reduce the unnecessary valvetrain noise (a.k.a. sewing machine sound,) with a superior cam consisting of lobes specifically designed for LS motors.

https://www.texas-speed.com/t-camshafts.aspx

Put in one of these Cam Motion Stage 1 cams and bump the LSA up from 118 to 120, and I bet it won't even be far off from the stock idle. (Personally, I think you'd be hard to tell between 118 and 120 LSA, as even with the 116 LSA and a good tune, it's not that far off.)

Unreal

What do you think the stock cam is designed for? A coyote?

Stock cam is EXTREMELY gentle and designed for a LS motor.

BigVette427

I'm talking about the lobe design such as those from TSP, Cam Motion, EPS, (and a few others), whose designs are superior to GM's lobes. This is in part where some of the typical LS sewing machine noise comes from. EPS simply calls it "jerk", and their website describes it well. There is more than one way to open and close a valve. Throw in an 8620 core (+$50 on a $400 cam) and you have a vastly superior camshaft, even if it were cut to GM's LS7 specs. Let's be honest, the General is a cheap bastard so it's not like it should be much of a surprise to anybody that they don't always have the best parts in their motors. Ex. $3 valve springs in a 650 hp LT4 motor.

http://www.engpwrsys.com/tech-notes/cam-design.html

Must_Have_Z

I went to a very "valvetrain friendly" Cam Motion cam (similar lobes to you). It was a mild cam too (in my definition) - 230/246 .634/.634 116+4. AHP Stage 4 heads. Still sounds as "loud" as before, which wasn't really that loud to begin with. Engine sound, like exhaust drone, is subjective I guess. To me, changing cams will only help a tiny bit with noise, if at all.

JesC6Z

Unreal

GM puts WAY WAY WAY WAY WAY more time and money and engineering into valve train than anyone else. Talking about 8260 core, or cost of the cam has nothing to do with lobe design.

Plus how do you know anything about the lobes? Just the marketing from TSP, etc? They say it is softer? Because marketing people would never lie. Have a conversation with Billy at comp about lobes and designing them.

BigVette427

You're not even reading what EPS or TSP are saying, (or myself, for that matter, ) yet you want me to take Billy's word for it? How many different lobe profiles does Comp alone offer? That's just marketing? Although they all open and close valves, lobe profiles most certainly do differ and there are certainly better lobe profiles out there than what GM offers from the factory. Hell, even GM turns to Cam Motion for their COPO motors.

RedZ4me

GM turns to everyone for parts, they assemble cars, not produce parts 😁

Unreal

All those companies have aggressive lobes, and endurance type lobes. Just reading a marketing claim that "our lobes are soft on valve train" doesn't mean anything was my point. Comp, Cam Motion, TSP, etc. They all say that because that is what people want to hear. How are they defining that or measuring it? Gentle compared to what?

Swapping to an aftermarket cam, to try to get gentler lobes over the factory setup, is a futile exercise. Now a endurance style high performance cam, that is gentler than an aggressive race style cam, sure a lot of companies offer a bunch of great options.

OP would be better off on working on investing on a high end setup of lifters, with individual measured pushrods, and lift bores machined perfectly, etc to fight valve train noise, than cam lobes over a stock cam, as there is a ton of variance in those parts, which is why some people have bad tick, and others don't, even with a stock cam.

BigVette427

In most cases you are correct, but the inference is still "whoever" makes the stock GM cams; not sure if they are all made by the same company or ground off the same cam grinder, or what have you. Point I'm making is the stock GM LS7 cams, there are better lobes to be had.

Talk to Geoff at EPS or Jason at TSP and you may be surprised what they can actually do. I've personally spoken with Jason at TSP, toured their shop, and looked at their Landis CNC cam grinder. Swapping a cam to get an overall more durable cam (8620 core) with better lobes is easy to do, just select one from EPS, TSP, or Cam Motion. While you're at it, you may as well play with the numbers and bump the power a little, depending upon what you're ultimately really trying to do.

The LS sewing machine noise is common between about 1,550 to 2,100 rpm and it gets that name because it literally does sound like a Singer sewing machine. That noise bugged the sh¡t outta my Dad going back to when he first bought his then-new 2003 Z06 LS6. (Still has one now but it's a different one.) Had a 2002 Z28 before that. My LS7 had the typical sewing machine noise that all LS motors do before I did my heads and cam, but afterward it really is all but virtually gone. Maybe a tad around 2,000 rpm but you really do have to strain to hear it.

I agree with you that a quality lifter such as the Johnson 2110 SLR (slow leakdown rate) lifters with .039" of measured preload that I went with probably did a lot to help reduce much of the sewing machine noise, but for a street driven motor with a hydraulic camshaft, there is no need to get into the short travel lifters that require 16 different length PR's. Anyways, it's the combination of the TSP lobes, even the moldstar 90 valve guides, and maybe even the CHE trunnions, that all went to combine for the way it sounds and runs now. All I can say is I know what the LS sewing machine noise sounds like and my LS7 now is the quietest LS motor that I have ever heard.

Lorenzo Serra

The OEM are a big part of the sewing machine sound. The OEM trunnions are a little loose while the CHE trunnion are super smooth rocker and very tight.