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Performance Cam

Well, anyone with an ATT, performance PCM reflash and 4" exhaust system is now not a standard 6.5er, so it begs the question, what is the next step? Because right now people are thinking thats the best they can do. (aside from the good reliability mods)

To me logically the cams, rockers, valves are the next step, and if going spendy on a set of timing gears working the cam project in isnt way out there. It just needs to be proven for people to take it seriously, and maybe it would become common in engine rebuilds.
 
Exactly Buddy why we went with a performance area to discuss going to next step,

I've been around the 6.5 forums for some time, and a lot of guys errantly read a post that says do this, looking for an easy bolt on or easy install doo-dad expecting big results and are sorely disappointed, then if it goes bang in process they wonder why.

So if cams, rollers, special intakes etc are your passion have a go at it,

No where did I ever say cams would not work, they are not for everybody, the population for those it would prove to be a benefit for and deep pockets, or access to inexpensive machining is rather small.

Ya'll are way too serious anymore, reading into posts that which was not said as you took to understood how it was intended to be meant, so when you see something in the main area what works for a run of the mill engine as a bolt on improver without a lot of extra considerations to be accounted for.

In this performance area theorize away, but folks will know we are talking performance then vs basic longevity & "bolt on" performance adders.
 
TD no one was jumping your case :dunno:

Since you brought it up though.....you are making a definitive statement that cams will only benefit a small group, that is a strong statement for not saying much.

If people are willing to discuss turbo performance and spend $800 on that for an efficiency gain, then I dont think anyone can yet make any claim that cam mods wont help a lot of people. Its kind of like you are pigeon holing the idea before it has been vetted.

Not that I dont agree with moving it to the performance section, no one was complaining.
 
Okay I'll type slow evidently the message isn't making the trip, For ......Most .....Of .....The ...... 6.5 .......Crowd......Aftermarket Cams........In......Their.....Truck.....Over.....&.......Above......What.......GM......Provided...Will.....Be.....Pretty.....Much.......Useless........Is......All......I .....Am......Saying,

I don't know how else to say it, and it isn't pidgeon holing we had been asked in the past to provide a performance area, just not enough discussions at the time to warrant it's own area.

We have CIL6 talking about a custom rig, and 635 fixing to do some serious dyno stuff, 6.5 Quest doing some things, 6265 Racer doing his thing, some guys talking about pane you being one of them, thought it would be a nice addition so guys looking for such things would not have to search the regular threads to find discussions along these lines.
 
I will be getting a custom billet camshaft made yes, there isn't a camshaft company out there that has the master for one of these camshafts. Keeping both valves closed for as long as they are on this engine is GREAT for 100% stock. Anything past that it creates massive pumping losses.

Pumping losses = less efficient = less power =more internal strain, and I think everyone wants a more efficient engine.

I will be eating up the initial research and design costs for everyone else, and was told that the price will come down significantly after I have a couple made. As in around the normal price for a billet roller cam :)
 
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Turbine Doc said:
Okay I'll type slow evidently the message isn't making the trip, For ......Most .....Of .....The ...... 6.5 .......Crowd......Aftermarket Cams........In......Their.....Truck.....Over.....&.......Above......What.......GM......Provided...Will.....Be.....Pretty.....Much.......Useless........Is......All......I .....Am......Saying,

I don't know how else to say it, and it isn't pidgeon holing we had been asked in the past to provide a performance area, just not enough discussions at the time to warrant it's own area.
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Youre not getting it. Your multiple reiterated statements ARE pigeon holing the idea as only for performance and I think that is wrong. By making your statements, coming from someone with such clout and people generally listen to. Unless you have tried it or seen the R&D from someone that has, I dont think that your statement can be made.

It could become a normal rebuild efficiency modification, when thinking out of the box. Someone told you it wasnt worth pursuing because no one would want to take the time and effort to do it. But if someone did it and proved it, it may not be useless to most people and may become a standard rebuild mod. I mean why use the factory design when you can put in better components while already into the engine?
 
Buddy,

Meet me half way, I think you chose the title of this thread performance cam shafts when you 1st posted it, so to me it belongs in a performance section.

There are many things done in past as "must do's" according to others, that I now disagree with, having done some things myself that did not net results expected and I've also learned from others, so please don't take it personal when I choose to think it's not a good fit for the basic 6.5 based on my understanding of the way things work; this is a discussion forum lets discuss it.

I'm more than willing to watch folks prove conventional wisdom wrong in cam shafts, ATT could not work either according to conventional wisdom, it was never heralded as a performance turbo but merely one to replace the GM turbo with, turned out that in some ways it does outperform the GM turbo.

As for your thought that I am pidgeon holing this, consider this until I posted in this particular thread today and we created the performance section, the thread was automatically pidgeon holing itself last post was 9-25-09 in the main 6.5 area. If I really wanted to pidgeon hole it simple as a lock thread so it would die on it's own burried deep into archived non active posts, or I could just have used a delete post function.

Missy Good Wrench, & a few others are on same page as I about cams as a power gainer for the basic engine, Yet you seem to think I'm the only one that has said I am doubtful it will net enough to be a worthwhile endeavour. I don't think its goin to work as SSD claims it will without doing some other things to take advantage of what might work in a tweaked cam.

As far as me saying earlier folks need to be less serious that was a collective statement somebody got upset when I said the Holset wasn't the best fit for the 6.5, I still stand by that, as extra stuff need to happen for that to be a good fit, and CIL6 suggesting I might want to disregard the assertions of a speed shop, I was not complaining about anybody jumping my case, I'm not sure of you singling me out on this cam thing though. If I'm misreading you I apologize, but that is what it looks like from this side of the monitor.

We are talking forced induction here on a relatively low rpm engine which should cover gains in the basic engine that hasn't been flow modifed in the intake runners or porting, or head flow changes, CIL6 is doing the things that would net gains accompanied with a cam change I would expect to be needed to get a gain from a reground cam.

Can we say at this juncture that we can agree to disagree that a cam on a stock 6.5 or even bumped up with a turbo, a reflash, a open exhaust, phaser gears, splayed mains, lowered CR will do much, I know guys running that way, have build an engine that way myself, nobody with that configuration has seen the need thus far to say I need a different cam.

So I'm going to stand by my recommendation that unless taking it to level that CIL6 is taking it to, once you do the standard bolt on mods you've hit the limit for where the bang for buck mods can take you. You can stand by your convictions that there is a benefit to a modded cam in the basic 6.5 and lets make a truce there.

Is this THE limit for the 6.5 most assuredly not, 6265 Racer is about as far as one could possibly go for now, I don't recall a special cam there.

Is the missing link that a cam would that get even more for the LSR, possibly CIL6 will let us know,

I'm dying to find out because it it works and can be easily plopped into a slightly beefed up 6.5 I'll be on the waiting list for one myself.

Before we spend a lot of time on cams however, IMO fuel is the next shortcoming & we need to be looking at more fuel before cams, I could be wrong on that position and if proven otherwise I'll man up to being wrong, not the 1st time but would be the 2nd time :D

Possibly it would have been better to name this section as 6.5 performance/6.5 R&D
 
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Turbine Doc said:
Possibly it would have been better to name this section as 6.5 performance/6.5 R&D
Click to expand...

Now that's an idea I can support... sounds so scientific and all... :D
 
Turbine Doc said:
Buddy,

Meet me half way, I think you chose the title of this thread performance cam shafts when you 1st posted it, so to me it belongs in a performance section.

There are many things done in past as "must do's" according to others, that I now disagree with, having done some things myself that did not net results expected and I've also learned from others, so please don't take it personal when I choose to think it's not a good fit for the basic 6.5 based on my understanding of the way things work; this is a discussion forum lets discuss it.

I'm more than willing to watch folks prove conventional wisdom wrong in cam shafts, ATT could not work either according to conventional wisdom, it was never heralded as a performance turbo but merely one to replace the GM turbo with, turned out that in some ways it does outperform the GM turbo.

As for your thought that I am pidgeon holing this, consider this until I posted in this particular thread today and we created the performance section, the thread was automatically pidgeon holing itself last post was 9-25-09 in the main 6.5 area. If I really wanted to pidgeon hole it simple as a lock thread so it would die on it's own burried deep into archived non active posts, or I could just have used a delete post function.

Missy Good Wrench, & a few others are on same page as I about cams as a power gainer for the basic engine, Yet you seem to think I'm the only one that has said I am doubtful it will net enough to be a worthwhile endeavour. I don't think its goin to work as SSD claims it will without doing some other things to take advantage of what might work in a tweaked cam.

As far as me saying earlier folks need to be less serious that was a collective statement somebody got upset when I said the Holset wasn't the best fit for the 6.5, I still stand by that, as extra stuff need to happen for that to be a good fit, and CIL6 suggesting I might want to disregard the assertions of a speed shop, I was not complaining about anybody jumping my case, I'm not sure of you singling me out on this cam thing though. If I'm misreading you I apologize, but that is what it looks like from this side of the monitor.

We are talking forced induction here on a relatively low rpm engine which should cover gains in the basic engine that hasn't been flow modifed in the intake runners or porting, or head flow changes, CIL6 is doing the things that would net gains accompanied with a cam change I would expect to be needed to get a gain from a reground cam.

Can we say at this juncture that we can agree to disagree that a cam on a stock 6.5 or even bumped up with a turbo, a reflash, a open exhaust, phaser gears, splayed mains, lowered CR will do much, I know guys running that way, have build an engine that way myself, nobody with that configuration has seen the need thus far to say I need a different cam.

So I'm going to stand by my recommendation that unless taking it to level that CIL6 is taking it to, once you do the standard bolt on mods you've hit the limit for where the bang for buck mods can take you. You can stand by your convictions that there is a benefit to a modded cam in the basic 6.5 and lets make a truce there.

Is this THE limit for the 6.5 most assuredly not, 6265 Racer is about as far as one could possibly go for now, I don't recall a special cam there.

Is the missing link that a cam would that get even more for the LSR, possibly CIL6 will let us know,

I'm dying to find out because it it works and can be easily plopped into a slightly beefed up 6.5 I'll be on the waiting list for one myself.

Before we spend a lot of time on cams however, IMO fuel is the next shortcoming & we need to be looking at more fuel before cams, I could be wrong on that position and if proven otherwise I'll man up to being wrong, not the 1st time but would be the 2nd time :D

Possibly it would have been better to name this section as 6.5 performance/6.5 R&D
Click to expand...


Is the .65 a "deadhead" system or dos it have a return line? And what are the big fuel issues w/ it?
 
There was some misunderstanding because no one complained about creating the performance section and moving the threads to it. Thats fine.

I was referring to the negative opinions being used as facutal statements. The mentality of its not worth it on anything but super racer builds seems illogical to me.

At least preface them with "In my opinion" or "I have never tried this, but heresay is..."

Better valve control and stronger internals has potential, for the same reasons the ATT has proven beneficial for daily drivers.
 
I wouldn't consider $200ish out of the reach of most to get that extra boost in efficiency. You know you don't need to add more fuel to make more power, and forced induction benefits from proper airflow.
 
200ish would be hella bad ass, Whole hell of a lot better the 600+ SS wants for theres..

And if your in there already why not?
 
buddy said:
There was some misunderstanding because no one complained about creating the performance section and moving the threads to it. Thats fine.
.
Click to expand...


Never said there was a current complaint on the issue of performance threads, there was at earlier time this year ta request to having a performance section, nothing so nefarious as sticking these post in "a corner" to keep off to the side, it was just that so many performance discussions going on that now seemed like a good time to create a localized area to discuss such things that is all that happend, hope we all is cleared up on this, can we get back to cam discussion.
 
Turbine Doc said:
If you can get decent gains for $200 with cam change alone, color me there as well.
Click to expand...

Yeah, the cam grind would be in that cost, but in order to get more lift reliably would need better rocker arm assemblies and springs, so some more cost, but if doing a rebuild the cost may be worth it. People are willing to spend $600 for timing gears, $450 for fluidampr balancers, why not eliminate that annoying plastic rocker retainer.

So I dont think anyone is qualified to say its not worth it at this point.
 
Whateverrrrr :rolleyes5:

As I said before, some have dabbled with cams or given more than passing glance on the the idea (Ricardo Engineering being one entitiy) and were not impressed with effort, I'm parroting their experiences & yes since I have no personal cam swapping experience in a 6.5, which apparently in your mind disqualifies me when asked an opinion "what do you think" somehow, why pile on me MGW in this same thread is saying similar things yet it appears to be just me you are having issue with :confused:.

I still stand by my opinion for now, & what I think that at this time; what is being sold is snake oil for the average 6.5er. (if you are looking for a you win in that discussion, we can agree to disagree on that no more comment from me there)

Is it time for a fresh look, with everything else that has come down the pike for the 6.5 last couple of years, evidently so, your earlier post was talking about something SSD is offering, until I try one myself I guess I'm not qualified to opine on that, but with SSDs history of inflated gains using their products let's just say I'm highly suspicious of results being promoted by them.

As far as replacement for the nylon buttons, I have that in mine already, no nylon buttons on my project engine, I'm trying something different there, but I've not shared it yet as the engine has not been installed or run yet, I wanna see if that works first before I talk much about what I did there.
 
You dont understand, the problem TD is with you emphatically posting your opinion as fact. Please preface it with IMO, IMHO, or the word might, may, some kind of qualifier.

Stand by your opinion all you want, but make sure others know its just that, an opinion.
 
The discussion is about CAMS, gentlemen.

At this point, there is no solid evidence to indicate that a regrind WILL or WILL NOT work - several people *think* that the gains to be had from a cam are 'chasing the wind' (nice phrase, Missy), and several people *think* that there are airflow efficiencies that will yield tangible results.

Arguing those opinions or sparring about the semantics of the statements (does it really matter if the statement is prefaced with IMHO or if the paragraph is finished with "this is what I think at this time"?) <insert emphatic "no, of course not" here>

As TD stated, let's just agree to disagree, and Move it along, please.

Personally, I also think that, for the average user, the gains won't be tangible, but for somebody willing to invest in a complete rebuild, including modified valve train, port/polish, gear drive (if the valves are going to be any closer to an interference position in an engine with such low tolerances, I want some greater precision in the control mechanism), there may be something to be had.

I am interested in the discussion, but there are enough ups and downs involved (pun intended) that it's pretty hard to be definitive about anything here.

 
Modded Camshafts and valve control will make a big gain in efficiency, because with less restriction (higher lift and longer duration) to push air into the cylinder you wont need as much boost to get sufficient oxygen in the cylinder to complete combustion. This will reduce the amount of fuel you have to burn to generate sufficient boost to complete combustion. Also, with greater duration to push exhaust gasses out there will be greater volume of the cylinder for fresh air to occupy.
 
Nice theory. They MAY produce these big gains... I fully understand the theory behind changing cam dynamics, and what you indicate as fact ("they will make") applies fairly well to naturally-aspirated gassers.

It isn't as clear in a forced-induction environment, especially one with the valve geometry of the 6.5 and the close-tolerance of the interference paradigm.

Assuming GM's engineers did their job properly, there exists already enough duration to get cylinder pressures above nominal with turbo assist... what we're trying to do with a cam dynamics change is to reduce the amount of work required to make that happen.

Hence the healthy skepticism... I put my first Crane cam in a 1965 Chevy SuperSport 327. I've seen them in thousands of other engines, many I have done myself. I LIKE cams... they're sexy, make the motor breathe better, and add some interesting dynamics to the idle profile of a NA gasser.

But I can't figure out why, for the life of me, Crane and others aren't aggressively marketing a regrind for the old 6.5, older 6.2, newer hummers, etc. If they work.

Perhaps, as Missy or Turbine Doc indicate, it may not work well enough to make enough difference to make it worthwhile on these engines.

Maybe it will. Maybe it won't. Until somebody does one, it doesn't.

I don't trust SSDiesel's claims - they have been BS too many times - when considered in the face of some of the more credible entities in the industry.

I do, however, believe in human engineering and the ability of people here to experiment and make things work better. That is what this discussion is about, not about convincing anyone to join one side or the other.

Have at it, guys... make this discussion move from theory to reality. I'm still very skeptical, but that doesn't make me less interested.

What's the "show me" state? I want to be from there. :D

ON EDIT - there are a lot of things done to this engine that make minimal difference, but that add-up to make tangible differences. Things like fixing the cooling profile when pulling large weight. This additive effect is real, and a Cam may well be one of those type of changes. That doesn't make it less valuable, just means it isn't a game-changer, all by itself. There aren't too many of those.
 
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