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Thanks G Atsma, 00pooterSS and Darth V8r
Yes I didn't care too much about outright power as it had plenty already. Id like to find the best compromise of power and efficiency (the sweet spot) and still have a bit of a lumpy idle as well.
Realistically I didn't rev it to the max often but regardless Im still faster than 95 percent of cars over here in Tasmania without ever reving it hard, I respect it and want to enjoy it for many years.
To be fast and have it last.
Tim, I try not to look too much at duration, split, pattern, LSA, etc. I just look at the valve events. Intake open and close, exhaust open and close. The rest is calculated.
346 powerband is almost ideal at 43 IVC. That will work great with stock intake or other intakes that mirror stock runners such as fast 90,92,102. You will generally get peak torque at 4800 and peak power at 6300. You can cheat that a little with the cam but that is where the LS likes to run.
In your case I would be looking at a 42 Abdc IVC and 4 btdc IVO. That will open the intake just early enough to jumpstart cylinder fill without PTV or making the car a pita.
Exhaust I would open at 50 bbdc, and close right at tdc.
That combination gives you a 226 intake duration on a 110 centerline and a 230 duration on a 115 centerline. So the spec is 226/230-112.5+2.5. Now you could just as easily do 113+3, and you would be down to three degrees overlap. Very manageable, easy to tune. Should make great midrange without falling off a cliff up top.
To really make it shine mill heads to 11:1 compression.
I think that EPS makes a shelf grind 226, BTR stage 2 is a 227 and so is a Cam Motion Titan 4. I know that BTR uses a soft lobe which is nice for a street car and has 4.5 degrees overlap. I'm not sure about what lobes Cam Motion uses but they are supposed to be easy on the valvetrain as well.
Thanks, after setting it up correctly Summit valve calculator tells me I'll end up with 40.5 ABDC IVC and 3.5 ATDC IVC if I retard it -2.
Quote
In your case I would be looking at a 42 Abdc IVC and 4 btdc ICV
I found a quote from speedtigger here, I did look at link he gave but couldn't really work out why retarding tends to hurt power from link
Quote
Retarding cams in general will shift the power curve upward, but don't expect much for power gains. While closing the intake valve later does bolster upper RPM power, generally opening intake later in a mild camshaft hurts power across the board. Have a look at this thread: https://ls1tech.com/forums/generatio...-oem-cams.html
The problem is generalities vs specifics. And that link is talking about OEM cams in particular
Let's take a cam such as 224/230-114+4. This would be a pretty decent mild to moderate street cam. The IVC in this case is at 42 abdc, IVO is at 2 btdc. This cam is designed to make peak torque around 4700 rpm and peak power around 6100 rpm. Pretty similar to the cam I recommended for you. Now, if you decide to retard the cam four degrees to gain rpm, you end up losing more in torque than you gain in power. Part of the reason is that you also delay the exhaust valve events, which fights your ability to rev higher. Your IVC is now 46, which will want to peak at 6800, but your EVO is also now 49 instead of 53, so it will end up peaking around 6400 and then fall off much faster past peak. Another reason is that increased overlap also supports higher rpm, and retarding the cam does not increase your valve overlap.
If you truly want to move the RPM band, it is better to simply re-cam. In this hypothetical case, I would jump to about 232/238-113+3, which would get you to peak closer to 6800, and have the overlap to support the rpm, AND open the exhaust valve early enough to support the rpm.
Ideally for higher rpm, you want a later IVC, Earlier EVO, Earlier IVO and later EVC. In other words, a bigger cam.
Thanks, the main reason I am reluctant to go bigger cam with more HP is I doubt it would have any effect on 1/8 mile time or 0-60 mph time on the street in an M6 3.46 diff. This is what I use it for, a quick dash from the stop lights, I almost never exceed 60 mph.
Ive noticed at WOT when I take first gear to redline from stopped position and go to second I seem to be at peak power for only the tiniest fraction of the time it takes to get to 60 mph.
In the above scenario I doubt it would be of any benefit to me and I might pick up a tiny bit of efficiency staying with a slightly smaller cam.
In this video he gives a good example of two vehicles one which much less power that is quicker to 60 mph, although it's not a apples to apples comparison to what I'm explaining here as the fast car with less power in his example is a Tesla well known for going quicker with less power.
Engineering Explained
5 reasons shouldnt care about HP (as much)
https://youtu.be/mUO5bp-wyLU
Lots of things affect acceleration fo show. The cam you pick barring any extreme is probably the least of it. That's why i asked what your acceleration goal you were looking for in the beginning.
Besides that you're never really looking for hp. You're always looking for tq.
Hi re quote below, I couldnt find what you were referring to going back through your posts and mine, I was a late comer to the thread.
QUOTE That's why i asked what your acceleration goal you were looking for in the beginning ????
I agree with what you say, although most duration increases up from stock duration with aftermarket cams tend to increase midrange sometimes significantly before duration is enough to begin to push peak rpm up significantly. For example many after market cam suppliers offer 3 or 4 cams advertising all offering more midrange as duration increases before offering a cam that makes significantly more top end power. Midrange would have an effect on 0-60 mph.
Well thats disappointing as I have recently purchased an upgraded 5 puck ceramic racing clutch (with sprung centre) here in Australia which is stiffer than the original. I used to be afraid the original stock one would not handle the power so I would baby it too much making me slow. I hope with all my expense on the engine I dont end up with a slower set up than before. I know I'll need to practice to get used to it.
Here are my dyno results (266 RWKW 356 RWHP) for my cam installed last year BTR 219/224 113+3 .551 lift -3.5 overlap on 91 E10 fuel. New cam is Crow 217/228 110 .590 lift, +2.5 overlap but has more gentle lobes (61 on exhaust). Notice that power drops quickly on BTR cam. Hoping to hold on to power till at least 6400 with new cam with wider split, more lift, heads mild ported and fresh engine. Perhaps Im being a little optimistic, should have gone a little more cam?
Goal for cam change was slightly more lope at idle at least 10 more RWKWs and hold on to peak power longer.
Forgot to do this earlier but here's my old dyno graph for the cam I recommended: 228/232 111+3 (6 IVO, 42 IVC, 50 EVO, 2 EVC) - Ed C grind. I chose it given I felt the valve events would be ideal for fun street driving and track days and it has proven to be the case for me on all tracks that I've had the car on thus far. Car has a killer mid-range and pulls hard out of the corners while also enabling me to rev it out to around 7k when it makes sense to rather than shifting. I think this or something similar to this from a valve events perspective would translate nicely for autocross. There's also a 226/230 cam recommended in the thread with similar events that also looks like a great option. I’ve cammed all my cars and motorcycles some multiple time and know enough to be dangerous but I’m not a pro, just thinking my experience may help provide some direction.
C5Z, 228/232 111+3 cam, stock untouched LS6 heads, stock LS6 manifold/throttle body, .040 Cometic head gaskets for ideal qunech and slight CR bump, 1-3/4" LTs, 3" O/R X, stock mufflers, stock clutch (intake restriction has since been addressed via going 90/90 and cam in now on CM lobes but I can't locate my other charts at the moment):
Last edited by StealthFormula; 01-29-2020 at 09:20 AM.
Here's a dyno of my bolt on ls6. Remember when i said their's **** more important than the cam. Or atleast don't cam it till it's ready.....well results of a stock cam.
^^Oh here we go...no need to start a pissing match between the right and wrong way to do things. We all know there's hp to be had with lighter clutches, fancy PS pumps, the **** you did with your transmission gears to reduce friction, oil pan mods, the list goes on and on. Your order of operations is different than most and I respect it and it makes sense but it's not always the direction for the masses.
It is important to note that you've spent FAR more money and time optimizing your bolt-on setup than a guy like me (and most others) have spent simply tossing in a cam, springs, and pushrods in their LS6 for similar end results.
What that all means is, there's more than one way to get it done and there's no right way because it's simply different strokes for different folks. As already said, your results are nothing short of impressive. However, I and most others decide to take a different path which in my case results in more money in my pocket and extra time with my family and on my motorcycle. To each their own.
Last edited by StealthFormula; 01-29-2020 at 10:07 AM.
HioSSilver, instead of just telling us all that there's "**** more important than the cam" and posting your dyno chart, how about you add some value by doing the following:
Give us a nice breakdown of all the modifications you've made to your engine, trans, rear, the whole nine, to achieve your stellar results. Please include approximate costs and time spent.
Once you do the above, someone can than make an informed decison if that is the ideal path for them or if a $600-700 cam package from TSP and a weekend to install it all is the ideal path for them. I'm not making this post to to be a jerk, I'm really not. And I'm not disagreeing that there's many opportunity areas i.e. reducing friction, rotating mass, etc. that could de addressed instead of or before camming a car...but if you're gonna tell us there's "**** more important than the cam" then you gotta give us specifics so that way people can make an informed decision for themselves based upon their budget, time, needs, desires, etc.
There are right ways and wrong ways to get it done. If there weren't then there would be no bad combos or guys wondering why they're not making the power they think they should. Just how it is. You can do **** however you want.....but that don't make it right.
There is no pissing match.....only results. Your results proved there is more going on that should be addressed before a cam.
When did a stock ps pump become fancy? Ive never ran reduced friction oil either. So why make **** up. My trans does have polished gears mostly for durability. If it makes you feel better subtract 5whp and still loose if it gains anything at all. Wtf you want me to tell ya. Subract the 6-8 for a crankscraper. Guess what?? You still lost. Wanna pull one of my plugs out next??
Yup light clutches should be a stable of performance cars. Although how much of it shows up on a dyno is up for debate. From my experience is next to 0. Now acceleration is a different story......and isn't acceleration why we modding these cars.
Biggest thing i see on yours is a stock intake and tb. You're probably leaving nearly 20hp and a better tq curve on the table vs a fast 90 or 102.
As far as i can tell op just hot some good info. No reason to be mad.
HioSSilver, instead of just telling us all that there's "**** more important than the cam" and posting your dyno chart, how about you add some value by doing the following:
Give us a nice breakdown of all the modifications you've made to your engine, trans, rear, the whole nine, to achieve your stellar results. Please include approximate costs and time spent.
Once you do the above, someone can than make an informed decison if that is the ideal path for them or if a $600-700 cam package from TSP and a weekend to install it all is the ideal path for them. I'm not making this post to to be a jerk, I'm really not. And I'm not disagreeing that there's many opportunity areas i.e. reducing friction, rotating mass, etc. that could de addressed instead of or before camming a car...but if you're gonna tell us there's "**** more important than the cam" then you gotta give us specifics so that way people can make an informed decision for themselves based upon their budget, time, needs, desires, etc.
i did. I asked him his acceleration goals and made recommendations. He wasn't looking to run 10s like me. So i gave him advice vs shoving a cam in it.
Back to the fancy oil pan crap. You have a batwing oil pan so you already have better oil control.
Last edited by HioSSilver; 01-29-2020 at 10:47 AM.
You don't have to prove anything to me and I'm not lying about anything, was just going off what I thought I've read about your setup previously and I am open to being corrected. I thought you had a Turn One pump but it may of been the guy who had the bolt-on C5Z that put out real strong numbers. No big deal. You are the two people I know of who've done impressive things with just bolt-ons so if I confuse you two it's not intentional. I said it before, I'm looking to take a similar approach as you with my other car so I'm not knocking you, it would just be nice to know the whole deal so that people can make an informed decision rather than just being told to focus on others things than the cam. It's expensive and time consuming to reduce mass, friction, etc. in the various rotating assemblies of a vehicle as an example. I realize there's more to it than just that but you know what I mean.
I more than knew my intake tract was a restriction going into it. My order of operations at that time was let's just see what it does with a cam and headers for ***** and giggles and I'll address the constraints thereafter. I begun by going 90/90 then lost interest in doing anything else to it. I've got plenty of more opportunity areas but I'm happy with the results for what I got into it so I'm good until I get the bug again.
But for real, you should let us know what all you've done to achieve you numbers. Take the making an informed decisioon stuff out of the equation, it's simply valuable information to the community.
Last edited by StealthFormula; 01-29-2020 at 11:26 AM.
01-25-2020, 12:48 AM
