Looking for the best under the curve power, while maintaining a stable, quiet valvetrain (<.6 lift) that's reliable. Mods are as follows: LS6 Intake, Ported 241 Heads, 2800 Stall w/ 2.1 TQ Mult. (Can always go bigger) 1(3/4) Headers into a Y pipe with a straight through muffler. Ford 9 rear with 3.70's. Nitto NT05 Radials (275-40-17) On rear. Stock bottom end. LS6 Timing chain, LS6 Oil Pump. I know I may need larger injectors (Currently stock 98 Inj. and Rocker Ratios) and will need springs, lifters, P-rods and such, I got that covered. Anyways...I have been doing tons of reading about cams and Valve events, and I "'think" I know what I want. Currently looking at cams such as:

CompXR275HR12: @.006 275/277, @.050 222/224, (.566/.568) 112+2LSA
Valve events: IVO 1, IVC 41, EVO 46, EVC -2; -1 Overlap.

CamMotionTitan2: @.006 275/280, @.050 221/226, (.595/.586)112+3LSA
Valve events: IVO 0, IVC 40, EVO 47, EVC -1; -1 Overlap.

CustomGrind: @.006 272/280, @.050 218/226, (.595/.587)112+2LSA
Valve events: IVO -1, IVC 39, EVO 47, EVC -1; -2 Overlap.

These should give me the under the curve power I am looking for, (IF*) I understand these VE's and how my engine should operate. Keep in mind my focus is on Torque, not HP. I don't need a big cam with overlap overlapping overlap. Any advice or pointers to steer me in the right direction would be appreciated, I really want to learn about how to make these engines sing.

 

I would say anything in the 226-228 duration intake and 232-236 exhaust would be where I'd look.

I think you're a little small on the cams. I've run larger than I have now and this is a very good balance of overall civility with a 227 intake. The 2800 stall is a bit small, but you can run a little larger cam still.

I usually recommend a 227/234 113+3 or thereabouts.

Look at these two:

https://www.briantooleyracing.com/ls...ge-ii-cam.html

http://store.cammotion.com/the-titan4

 

I had excellent results with 224/228 112+4... Lots of fun on the street with stock like street manners.

 

What kind of Lobes were you running?

 

Anything from Cam Motion on their street series will be a good lobe... from Comp, the LSL and XE lobes are both very good. I'm running LSL/XE now and had EPS lobes from Cam Motion before. No noise with either.

Also, if you stay under 4 degrees of overlap @ .050" you'll retain pretty much stock like drivability. Your 3.70s will help a lot there as you won't cruise in 4th at 1200-1300rpm, where you'd likely encounter issues with a larger cam. So it almost becomes moot.

 

I think that your off to a great start here. Your splitting hairs between those three cams though. If it were me I would go with the comp Xr275 cam. It's got gentle lobes that could easily be handled with cheap LS6 springs and it's a proven performer. Don't be tempted by everyone telling you that you have to go bigger. I'm running a cam with even less lift and overlap than any of those three you listed and I embarrass the donkey dick cammed cars At my local track all the time, I love it when they think my car is a completely stock time capsule and then they come back after the race looking for nitrous bottles. I tell them that I just have an R/V cam haha. Remember also that the greatest cam in the world spec'd by Zeus himself isn't anything without an excellent wideband tune to go with it. That's even more critical than a few degrees one way or the other on the camshaft. Since you have done your homework you will learn the most from going with the cam of your own choosing. Remember that your LS6 intake is going to limit peak power to about 6300 rpm. The longer durations may carry out farther past that point but they will still peak at 6300 and only at the expense of low/mid-range tourqe and low end responsiveness.

 

That's what I thought, it appears that a IVC event of about 42 really bring the power home under the curve, while peaking at around 6200 RPM. Since LS heads are so efficient and have a 80+% Int-Exh flow ratio that you don't need huge exhaust duration to get things flowing. I'm curious as to what overlap is optimum for daily driving. -4 seems to be the go too for Cali smog sniffers, I have no such worries here. Only thing I am concerned about is drivability. Is anything over 0 deg @.050 overlap too much? (what is that like ~54 @.006? without doing the math) What is considered a lot and a little?

 

Please read my post above.

4 is the cutoff for daily drivability. 8 is the cutoff for streetable.

I have had 16 degrees and 6 in the current motor. And those are accurate guidelines.

As far as overlap at the valve... lazy lobes will idle worse and produce less vacuum. So there's some incentive to use proper lobes... weighing valvetrain stability with aggressiveness. In this respect, the LSL lobe is very good.

 

Ah I see I read it as -4 for some reason. So perhaps the CompXR275HR12 but on a 110 to tighten the ICV a bit for more low end grunt? Paired with XE lobes? I assume a good tuner can tuneit without too much trouble?

 

Yeah. XE are a little lazier - they work better on the exhaust side as you want a little more duration there and a little less lift.

A 227/234 113+3 gives you an IVC of 42 with ~4 degrees of overlap. Hence why I recommend it.

And more exhaust duration carries the power uptop with these motors but allows for the 6200 peak. So you can set your shift points around 6600-6700 and let it fly.

 

Ahh I see. That makes sense, Thanks for that info.

 

Off the top of your head, can you think of a cam that would give more low-mid range power? Since I peak at 6200 I am thinking that perhaps more average torque would benefit me, as a daily driver street car. Ill take your advice with the lobes, run a LSR intake and XE exhaust lobe, around just under .6 lift (although no higher as I want to run 918/1219 beehives) and head flow is negligible at that point. 224/228(112+4)? IVC at 40 and EVC at 50. 2 deg overlap @ .050. Or am i going about this wrong and it will this kill power?

 

Bspeck82,

Very interesting info in this thread. I am also on the hunt for a new cam and want under the curve power, while maintaining a stable, quiet valvetrain. It sounds like we would like something similar?

My car is a heavy 2004 Holden Monaro (04 Pontiac GTO equivalent). My Ls1 engine combination seems quite similar to yours although I have a 6 speed Manual. I have a CAI (OTRCAI), LS6 intake with ported TB, headers, high flow cats twin 2.5" exhaust, ported 241 heads and stock bottom end. Diff gears are 3.9s. The cam in the car is currently a 216/220 .600"/.600" 112. It delivers the torque but the lobes are a bit noisy.

Unlike most people however I want to keep the idle note to a minimum. So minimal overlap. Good street manors is the most important thing to me so torque matters. I wont be racing the car or anything. Based on my current experience I am not going to go lower than 114 LSA on this one. It sounds like this may not be a concern for you.

I have been looking at this cam even though I would have to import it into Australia since I don't think CamMotion are sold here:


CamMotion Torque Titan LS Camshaft v2: 218/226 595"/.587" 116.

I calculate the overlap to be -10.00 degrees which should be quite stealthy.

My reading on here suggests CamMotion are a good choice if looking for quiet lobes. My concern with this cam is that it that on 116 LSA it will provide the quiet idle I want but I may lose mid range power. Perhaps CamMotion would grind this on 112 LSA for you?

The other option I have been looking at may be to purchase a Custom Comp on LXL lobes (Comp should be easier for me to obtain in Australia as most vendors here use Comp or a local manufacturer named Camtech):


Comp Custom LSR on LXL lobes: 218/226 .598"/.605" 114.

However I calculate the overlap to be -6.00 degrees which is the same as my current cam which has a bit more chop than I want despite being tuned to remove it.

On 112 LSA I think that is that may deliver exactly what you want?

 

I looked into this cam. I believe that when you set it to a 112+3 it results in good events, perhaps Comp cam grind one similar with their lobes (and cheaper) You may also want to look into the XR265HR15, perhaps advance it a little and run different lobes? Also, have you tried magnaflow exhaust? Its what I run, absolutely no rasp, deep rumble and seems to muffle a bit of the lope. Or perhaps weld a high flow bullet into the I pipe?

 

Thank you for the response, I had looked at the XR265HR1, it's been used by a few people down here in Australia but as you mention I was looking to the newer lobes and the lift is low for my ported 241 heads. Reading the comp lobe catalogue they do make an LXL lobe combination that would be similar, 214/222 .595"/ .602" . So a custom order on 114 LSA it delivers a stealthy -10.00 degrees overlap. Well worth considering.

We don't have Magnaflow down here but I do have a heavily muffled exhaust but the lope of the cam gives it away, staying somewhere around the current level would be ok to be honest, just with quieter valvetrain and a little less lope than the current Comp cam and I think I would be happy.

 

Have you looked into VCM?

 

Ah, you guys know of VCM? I have reviewed the VCM range of cams, for some reason a lot of tuners in my home town of Sydney don't like using VCM cams. I am not sure why that is. Camtech seem to be the alternative to Comp here.

 

I've been led to believe cam motion are the best for gentle lobes and was looking at the titan 3 myself.

 

Streetable, driveable, etc. all relative terms. What I consider DD and my wife considers are two completely different things. Since you're not planning a rev monster, zero overlap will be fine for your goals.

If you have anyone nearby with canned motors, see if they'll let you test drive them. Get a feel for the various cams.

Moar overlap means moar tuning heartburn. So again, for your goals I recommend capping at zero overlap

 

Ya there lobes from adv to .050 come up to be 54. While xe are 53. Should be quiet and reliable for sure especially on an exhaust lobe.