Cam question

[Camaro2ss2010]

For those that have cams or have a great deal of knowledge about them will you give me some in-site on what is the biggest stage cam that I can install and still maintain everyday drive ability. Of course I will install the supporting mode with it (valve springs, pushrods, gears, etc..). I currently have CAI intake, ported throttle body, Texas speed 1 7/8 LT headers with off-road connection pipes and a tune. Current power to wheels when put on the dyno was in the 440 range. I have a 2010 2SS/RS M6.

[Clarkstar]

Texas speed stage 4

[davidscamaro]

Stage 3 cams for 5th gen are safe bets , stage 4 are getting close to ptv clearance but still fine in most cases

[G8One2]

For daily driving, stick with a cam you can use beehive springs with.

[Camarokid1996]

I've heard excellent things about GPI cams and will be going with a stage 3/4 this winter. People rave about the drivability even being a big cam

[acammer]

First - let's get something out of the way. Forget this whole "stages" thing that people will talk about. Every cam designer "stages" their cams differently, so the "stage" is basically meaningless. For example, I have a GPI SS3 in my car, which is bigger (more duration, more lift, more overlap) than a BTR Stg4. When comparing camshafts just look at the actual @ 0.050" lift values to compare apples to apples when looking at duration and lift.

When comparing driveability of a camshaft you want to look at overlap @ 0.050" as a good measuring stick between camshafts. Negative overlap up to maybe 4* overlap essentially should drive like stock, up to 10* is very reasonable (mostly a noticeable idle, and very mild "cam behavior" such as light shudders at low rpm and load), up to 20* is starting to get into some compromises (fuel smell at idle, some low rpm light load shudders, some difficulty at parking lot speeds with bucking in M6 cars, decreased fuel economy), and 20+ degrees overlap things get even more rowdy.

Something to keep in mind, M6 cars will "show" their camshafts driveability a lot more than an automatic car. Auto cars have the torque converter acting as a nice dampener at low speeds, where bigger camshafts behave their worst. So, a big cam in an auto car at parking lot speeds is no big deal, but with an M6 car you need to be ready to slip that clutch a bit when creeping along.

Knowing how to calculate overlap will be very helpful as you compare camshafts. The formula would be intake duration + exhaust duration (@.050) divided by 4, minus the LSA, times 2. For my camshaft, that's 233 (intake duration) +253 (exhaust duration) /4 = 121.5 - 112 (LSA) = 9.5 * 2 = 19* of overlap. Everybody has a different opinion on what's "streetable" - I would consider 19* getting towards the upper end of what's "streetable" with an M6 car - but still very reasonable when tuned properly.

Speaking of tuning... The camshaft has a whole bunch to do with that, but just as importantly is the tuning. For example, I put a lot of effort into tuning my GPI SS3. My tuner did a fantastic job with the car, WOT fueling and spark are spot on, and it was far better than 95% of tuners would ever do with respect to driveability. Because I like to tinker, I have spent countless hours refining and perfecting the tune. As a result, the car drives very, very well. I have driven cars with half the overlap that drive twice as awful - it just takes some time to really dial in a combination. So, when you choose a cam, you should think about who is going to do the tuning, and if they will do a job you're happy with.

I strongly encourage you to give the fine folks at GPI a call. Not only do the have some of the very best camshaft grinds you could hope to stab into your LS3, but they also provide incredible customer service before and after the sale. Finally, and most importantly, they have a remote tuning option for their customers. Their calibrators know exactly how to make their camshafts behave, and have driven some GPI remote tuned cars I can vouch that they do an excellent job.

[G8One2]

Also, be honest with yourself in respect to what your really doing with the car. It's easy to over cam a daily driver. Let GPI or whatever cam grinder you go with know what your goals are and how you will be using the car a majority of the time. Big cams that make big numbers on a dyno at 7000rpm isn't always the best choice. You want power under the curve for driveability.

[GAD]

I went with “stage” 3.2 TS VVT CAM. And honestly I would have been more comfortable with TS stage 2 or 1. I DD my Camaro practically everyday. I think a smaller cam would have been more enjoyable for my application. I have d*** for power under about 3500 rpms. Mine Camaro is also L99, so I have a high rpm stall that doesn’t help. I’ve always had a bad habit of going big or going home. Lol.

[G8One2]

The LS3 does very well with smaller cams. You'd be surprised how much power you can get with a mild cam. Besides, HP let's you brag, torque wins races.

[CFD]

There's nothing wrong with big cams when set up and tuned properly. Equally important are the relating components. My current cam is quite large and is much more driveable than previous stage 3 and 4 cams I previously ran. Some may disagree but get rid of aluminum rockers on a street car.

[G8One2]

What's the point in a big cam if your peak torque is at 6000rpm or higher. Beneficial if your a track only car and launch at 3500rpm or more. But in a street car that is daily driven, with the occasional track pass, big cams are stupidly annoying to drive. Very little off idle torque to get the car moving. Stall converters help, but driving around town or just all around daily driving, your never in your power band. It's not all about how much power a car makes at WOT on a dyno, because realistically, you will never be driving your car like that. Seems all people care about are big dyno numbers which don't really mean anything other than bragging rights.

[CFD]

It all depends on the cam grind and supporting mods. I can only speak for myself but when I went with a"big cam" on my daily driver I had drivability issues, needed high idle, had to add a vacuum canister for power brakes etc. etc. After I went over my issues with Kip at Cammotion he ground me a new one, just as "big" and it made a huge difference. Idle was normal again, no more vacuum issues and driveability was much better than with more popular stage 3 and 4 cams I ran before. Perhaps we have different thoughts on what a big cam is, typically when someone says big cam I think of high lift. Mine is 720 on the intake and 714 exhaust, perhaps that's not big.

[G8One2]

Duration@ .050" is usually what people are referring to as cam size. Anything over 228 on the intake duration is too big of a cam IMO. Also, different cam grinders have different ramp rates to their grinds. Lunati and comp cams grinds are generally aggressive with a rate of 50 deg. Aggressive cams are hard on valve spring and the valvetrain as a whole, and require frequent inspection of spring pressures because they wear out springs, and require dual valve spring to aide in controlling the valvetrain. Cam motion cams are a bit easier on their ramp rates with about 60 degrees making them easier on the valvetrain and spring longevity, and usually allowing the use of beehive springs, resulting in a quiet and more stable setup. If you know what your trying to do with the car, its easier to pick out cams that suit your needs. Big cams that make 520hp but only 430lbft of torque won't be any faster than a car that makes 470hp and 450lbft of torque (all else being equal). It really all boils down to what your using the car for and where your intend to use your powerband. Street cars do not need huge cams to make power and be a fast car.

[acammer]

Originally Posted by CFD

It all depends on the cam grind and supporting mods. I can only speak for myself but when I went with a"big cam" on my daily driver I had drivability issues, needed high idle, had to add a vacuum canister for power brakes etc. etc. After I went over my issues with Kip at Cammotion he ground me a new one, just as "big" and it made a huge difference. Idle was normal again, no more vacuum issues and driveability was much better than with more popular stage 3 and 4 cams I ran before. Perhaps we have different thoughts on what a big cam is, typically when someone says big cam I think of high lift. Mine is 720 on the intake and 714 exhaust, perhaps that's not big.

I agree - a well spec'd "big cam" with proper tuning will drive just fine. I'm interested in what your overlap @.050" is - that usually has a very large influence on driveability.

Originally Posted by G8One2

Duration@ .050" is usually what people are referring to as cam size. Anything over 228 on the intake duration is too big of a cam IMO.

If we're calling anything over 228@.050 on the intake side a "big" cam then the GPI SS3 in my car (at a 233/253) is "big cam" I don't have any significant driveability issue, and I have plenty of bottom end torque - I've yet to meet I hill I can't cruise up in 6th gear at 1500rpm. It's true, I don't make peak torque until about 5350rpm (stock cam peaked at 4500), but I'm ahead on torque vs. stock cam from 3250rpm on up, and was still making over 300ft/lbs at 2750rpm where the pull started. So, I definitely disagree that a "big" cam can't make reasonable, driveable, bottom end.

Originally Posted by G8One2

If you know what your trying to do with the car, its easier to pick out cams that suit your needs. Big cams that make 520hp but only 430lbft of torque won't be any faster than a car that makes 470hp and 450lbft of torque (all else being equal). It really all boils down to what your using the car for and where your intend to use your powerband. Street cars do not need huge cams to make power and be a fast car.

I agree - that you need to know what you want to do with the car before you choose a camshaft. Gear, converter for auto guys, compression, intake manifold, heads, and most importantly what you want from the car, all influences your choice. I struggle with your 520/430 vs. 470/450 example - horsepower is a measure of how much work can be accomplished, and 10% more work being accomplished is going to get it done faster. You gave the modifier "all else being equal", there are a lot of ways to interpret that. I'm guessing you meant same car, same weight, same tire, same gearing - and I think that without the right setup the big rpm car is not going to show it's full potential, but it's still gonna be quicker down a quarter mile.

I'd interpret that different though - with all else being equal meaning each car is the same power, weight, traction, and the driveline (converter, gear) is optimized for the combo. In that case, the 520hp car is really gonna stomp on the 470hp car.

Overall, I get your point. I see plenty of guys putting donkey dick cams in cars that aren't otherwise really optimized for them, and they'd likely be better off with a more appropriately sized stick. Heck, I bet half the cammed cars out there rarely if ever truly get revved through their full powerband to the very top where they really should be shifted. Don't get me started on the "shift at peak torque" crowd!

But, the big cams have a place for guys that are willing to build the car to suit that choice, and use them as intended. They certainly don't have to drive like crap and be dead on the bottom end. Just food for thought - I enjoy a good conversation like this.