Can you cite a source? I'm genuinely curious as I have a thread going about said LS3 AFR's

 

No source, just been pouring over all the numbers etc etc etc from those 2 heads for the past month for 2 different customers. In the end both went with trick flows.

Any company can take a head and make it better, but then you are well out of a regular budget and sending x head to y company etc.

Out of the box fit, finish, as is potential are what i focus on with the customer. saying oh you can buy this $2400 set of heads but then they turn into 3k+...thats not realistic for most.

 

Saying the AFR LS3 is not better than the TFS LS3, given who
Designed them and his history designing Cylinder Heads is
Like me saying your hi lift asa cam is no better than the original
asa hot cam, clearly ludicrous.

I agree with GAtsma & John B, regarding camshaft design by Livornois for
LS3 Heads with exhaust splits less than 10* especially for OE
Castings with less than 70% E/I ratios. Could not find flow #s
On Livornois site.

You made recommendations and then countered John B., KW Baraka,
and Darth all of whom have extensively brought data and research
To this site for a long time! The OPs original cam choices are
Unreasonably small for a 416" and have poor exhaust splits
As well.

The Customer has the right to specify Heads or Cam on a build
If that's what he wants and knows WHY he wants it.
Those small cams will not make 600 Crank HP with Liivornois
LS3 Heads I would be willing to bet.

As a vendor who joined last year you may want to check
Your attitude just a bit.

I stand by my original suggestions.

 

We have been a vendor on here for a very long time. This tech acct was made last year.

The claim is not ludicrous at all. Ive given you exactly why i said what i did, and i stand by that also. I do a large amount of research for our customers so they get the best for their budget and goals. If afr were it, id say afr and no one would mind recently. There are plenty of facts and real world comparisons out there as well as the technical specs of the heads themselves as well.

Livernois has a very high quality head and im sure they know what they are doing. they have performed well in quite a few comparos in magazines also. They arent on here as much to defend themselves, but they are more than capable to do the job with their in house parts.

There are many ls3 cams out there, not all have to have double digit splits. SpinMonste got plenty of sales and cred for his 232/234 cam. i dont like it but it made power.

 

Not saying double digits exhaust splits are necessary either,

I used a +6* exhaust split with a LLSR (which you have
Been dismissive of with other members) along with
MMS TFS LS3s and made 690 HP @ the Crank
7100-7300 RPM from 396". Very Happy with the
Results from both to say the least.
If I was starting today I would use the AFRs.
Not saying the difference is huge or even significant,
But definitely noticeable at the upper limits.
Time marches on and so do improvements.


Either AFR or TFS LS3s out of the box would exceed factory
Ported castings and +8-10* exhaust split is the sweet spot
With ~ 230* Intake duration being the sweet spot for
A daily driver 416" with the aforementioned Heads
IMO.

Friend of mine building 416" with AFR LS3 & LLSR
in 3000 lb SN 95 Stang w/Glide & 4:30:1 shooting for
620+ RWHP & High 9s.
Much different combo obviously.

I do a lot of research as well.

 

I havent been dismissive. I dont use the solid rollers for 99% of builds amd customer recommendations and i really see no need for them on most street builds. 600rwhp is nothing new on ls3 stroked engines with hyd rollers even. It is fun yes and a milestone, but again its been done. If (nearly) cam only ls3s can get 500rwhp its not too much of a stretch to expect 600s. diet coke did it with a 5th gen in 2012 or so he wasnt the first but the first one that comes to mind. made 630ish iirc.

Im not saying you are wrong and i am right on amy of it or vice versa, but from my professional experience and research the tfs are hard to beat.

I WILL say that because of this post, a few places have asked me to check out their out of box heads to compare with. We shall see what that brings.

Most people dont have the ability to work with the solid roller stuff or budget so a drop in hyd roller on brand new lobes fits them better.

 

If I had to choose between those two camshafts, I would likely pick the low lift version for use with stock rockers. The higher lift will certainly make more power, but it can also cause accelerated wear when used with stock rockers. On a car that sees a lot of street miles, this will be more of an issue than a weekend warrior. Another thing to consider is valve train noise. While I don't know who manufactures Livernois cams, some manufacturers use harsh high lift lobes that can be noisy. This can take the fun out of driving the car.


This camshaft was designed for people who want the extra power of a stroker, but still want to maintain great street manners. This camshaft has a milder idle than most performance cams and will have great street manners. And, unlike many of the other cams mentioned, it was specifically designed for stroker engines with mild to moderate compression ratios. If you want to discuss your choices further, feel free to contact me: Steven at CamMotion.com

 

Steve, dumb question, but maybe relevant here - in the third gen section, I'd say the rule of thumb is around 0.600" lift you should really look at roller tips. Maybe the real number is 0.620 or something, but you get the idea.

Is it the same basic rule of thumb on fourth gen rockers? Somewhere in the 600-625 range it's time to step up to rollers?

 

Had no idea this was such a divisive subject.


The heads I'm looking at are very good heads. Not stock. These are completely refinished racing series heads, top of the line from Livernois.
They're going to perform well I have no doubt about it.


As for the Cams, I can put whatever I want in there.


Looks like this Cam motions would be a good fit. From looking though its not extremely different than the Livernois stage 2 Max.


Cam motions,


Grind # XA230/365-XA240/355-16+4
Street Performance
Duration at .050: 230/240
116 Lobe Center Angle with a 112 Intake Centerline
Lift with 1.7 Rocker Arm Ratio: .621"/.604"
Usable RPM Range: 2200-6200




Livernois stage 2 max
P/N LPP801127


Intake Lift 235@.050
Exhaust Duration 242@.050
Intake Lift .603"
Exhaust Lift .618"
LSA 114


According to some stuff I have been reading its better to use a lower LSA with a manual trans.


What are you guys thoughts?

 

I don't really look much at LSA until after the fact. First thing I do with any cam spec is break it down into the valve events. For street manners, I look at OVERLAP. For a manual transmission and a street manner focused build, overlap is king. You want less overlap for better manners. Sorta what Russ K was saying above. Now, if durations are identical, then a wider LSA is smoother driving, but again, that's because a wider LSA reduces overlap, assuming identical durations.

That cam motion cam has 3 degrees of overlap at 0.050. This does come down to personal preference, BUT, I drove a zero, a 3, a 7, and now a 10.5 (warm) degree overlap cam in a 346. TO ME, there wan't that much difference between the zero and 3. The 7 got a bit choppy, and the 10.5 took some serious tuning effort to tame it. 10.5 happens to be the overlap on the livernois cam. So, between the two, the cam motion 230/240 will be a smoother driving car vs the 235/242. And not just the bucking - return to idle routines get really tricky with higher overlap.

Displacement - especially stroke - tends to absorb overlap. SO, based on my preferences and likes, etc, I can't imagine a 3 degree overlap being anything difficult to drive on a 416. I can imagine the 10.5 overlap will be a pain, but it should be easier to tune out vs on my 346. I can't speak for you or your wife, though. I don't prejudge women, my daughter drives the **** out of her truck and beats Br0's with it all day long.

Honestly, of every cam mentioned on this thread, I like the 230/240-116+4 the best for your goals. But I'd actually request for the intake centerline to be on a 113.5 vs a 112 if you think the occasional track day is in the cards.

Back to the LSA question - I could do all kinds of examples showing cams with different durations and different LSA's that would all have similar street manners. To keep it simple, I'll look at the Titan 4, also from cam motion. 227/232-113+4. It has 3.5 degrees overlap. Compare this to the 230/240-116+4 above at 3 degrees overlap. These cams are very different, yet they would behave similarly in terms of street manners and idle. They make power at very different RPM ranges, and they are intended for different duration engines.

Anyway, there's my $0.015

 

Darth knows what he is talking about!
The 230*/240* Cam Motion Cam is the best cam for your goals/needs
Mentioned in this thread so far. +3-5* Overlap in a 416"
Will tune and drive very easy!

 

Lobe center angle causes more confusion that it typically helps for your average enthusiast because it has a relationship with the camshafts duration and the lobe centers. Because the LSA's affect on valve events is dependent on those other factors, LSA by itself is not enough information to predict performance or drivability characteristics.

If you really want to understand what is happening, you are better off to look at the valve events, overlap and to some degree the lobe centers. Here is an illustration using our free Cam Motion Cam Timer that shows valve events, overlap and lobe centers:



Here is a comparison of two camshafts with identical intake and exhaust durations @ .050" of lobe lift. The camshaft displayed on the left side Cam Timer has a 116 LSA while the camshaft displayed on the right side Cam Timer has a 112 LSA. These specifications are circled in red. Again, otherwise, these are the exact same specs with only the LSA changed.

Next, have a look at the specs circled in orange. This is the "overlap" or the period of time at TDC when both the intake and exhaust valves are open at the same time. This specification is the greatest determining factor on how smooth the idle is and how "fussy" the engine will be at low RPM. This is also the specification that will have the greatest affect on how much the engine and drivetrain might buck at part throttle during lower RPM operation in cars with manual transmission or automatics with a lock up torque converter. Generally, overlap has the biggest effect on manners. With that said, camshafts with more overlap generally make more power at high RPM. So there is a trade off with this specification.

Now look at the specification circled in purple. Notice how the camshaft with the 116 lobe separation angle has an intake valve close of 47 degrees whereas the camshaft with the 112 degree lobe separation angle has an intake valve close of 43 degrees. An earlier intake valve close will create more lower RPM power and torque at the expense of upper RPM power whereas a later intake valve close will create higher RPM power at the expense of lower RPM power.

Now, if you play with the Cam Timer, you will find that changing either the LSA or the advance will change the lobe centers and all of the valve events, so it has multiple effects. So, generalizations about LSA can be very misleading. But, one thing that you can hang your hat on is that when you change the LSA of a given camshaft, it will change overlap. A Wider LSA on a camshaft with given durations will reduce overlap while a narrower LSA on a given camshaft will increase overlap. So, in this example, the 230/240 camshaft on 116 degree LSA will only have 3 degrees of overlap and hence have a smoother idle and better manners than the camshaft on a 112 degree LSA that has 11 degrees of overlap.

 

I have an LS2 based 402 with LS3 heads. I spec'ed my own cam at 226/242 on 117 +5, but it wound up being +3.5* when degreed. Comp EPS lobes at ~600 lift. Zero degrees overlap at .050. Stock heads, stock intake manifold, stock exhaust manifolds it made 470whp/450 ft lb. It makes really good power from 4000-6000, will rev to 7 if you ask it to but power falls off like a rock above 6500.

Even for a "stealth" cam I wish I had gone a little bigger. With a good idle tune it really doesn't lope that much. Power is too soft down low and doesn't carry as high into the rpm range as I expected. The stealthy stroker cam would make a lot more power everywhere than my cam with a very minimal increase in lope at idle. The high RPM falloff is a mechanical mismatch of parts rather than something that can be bandaided by a cam. Lesson learned - don't try and make a stroker rev to 7000 unless you have the airflow to support it.

Honestly though I don't think a stealth cam suits your build. You'll get a way stronger butt dyno feeling with something a little more aggressive. For your build I like something more like 232/242 114.5+4 - 8 degrees of overlap. A good tune and it should drive respectably.

The car will feel much stronger with a more aggressive cam and I think you'll feel better about the money invested. The stealth cam makes for a stock type driving experience, and a broad very mushed out power curve that won't really set your hair on fire.

 

Cutting that on a narrower lsa would have made it feel alot better and having a 114ish icl is prob why it didnt produce as expected vs cutting it bigger. 112 would have helped the bottom end more but like you said you asked for 5 and got 3.5. did you use an adj timing set to make up the difference?
Bigger would change the way it makes power etc yes, but having the orig designed a bit better would have been more enjoyable imo. a 117 is pretty wide even when looking for a stealth cam.

 

I agree the narrower LSA would have helped a lot, but my goal at the time was to limit my total overlap to 0* at 50. It is a lot milder than I expected and I think grinding it on 114 would have made a huge difference without being too wild. I also wanted to maximize exhaust duration thinking that the exhaust manifolds were holding me back upstairs.

I do have an adjustable timing set in my engine and could have moved it. Honestly I got a little gun-shy of the +5 I ground it on and was worried power would fall off too soon. I think what happened is I have airflow restriction coming in hard at 6000 rpm and I just gave up free torque in the midrange by not advancing it further.

I was really trying to get maximize the useable RPM range of the engine even if it didn't produce as much peak power. It's a 2800 pound car with a 6 speed and 4.10's. Ran 130 in the quarter so it isn't a slouch.

I swapped in 3.73's and a T56 magnum with longer gear ratios and it feels a bit neutered now. Imagining my engine in a 3800 pound camaro with even longer gear ratios I think it'd put you to sleep.

I will be re-doing everything here pretty soon with intake, heads, and headers that can actually support the power I want to make

 

Rule of thumb is normally advancing doesnt hurt the power up top as much as retarding hurts the power down low. Plus youve got good duration and a wide lsa to keep the power going up top.

 

These two cams are different to almost a significant degree! There will be a very different driving experience with these cams, no matter who does the tuning.

What Darth said.

Between the cams you have listed, and with your stated goals......hard to come up with a better choice than the CamMotion cam.

KW

 

I have a LS2 with GM heads with the 280cc head work by Advanced Inductions with a Rick Crawford ported intake. I'm running a Cam Motion cam 230/238 113 +3 .626 lift. It pulled 480/434. Now I want to go with a 402. Will I need a new cam? Sorry not trying to step on your thread.

 

Youll still make good power with that cam. going bigger cid doesnt automatically mean bigger cam

 

The great thing about more cubic inches is that you can more more power within the same RPM range by going to a larger camshaft. This will allow the stroker to live up to its potential. Send me an email: Steven at CamMotion.com with all the details of your new build and I will help you get the perfect camshaft for your goals.

~Steven