TU and F4 Camshaft Follow-on Discussion

[Shadow]

Is it beer thirty yet?

Almost there Bro!

So the degree wheel doesn't synchronize with any particular point on the cam, it is just installed as a reference point?

Correct, once you find the location on the cam, via the book method and using the dial indicator, you simply Mark that degree (for eg.) right where the Pointer IS pointing and then you can dial degrees Forward/ Backwards ect.

I just looked through the thread again and I can't find where he said or implied that. From what I read he was going to use the max lift as the centerline, but he doesn't really say. He glosses over many details and that is why I started trying to nail down exactly HOW he would accomplish this.

Well, this was Also a "missing" piece of the puzzle that my Lizard brain Added in to make it all work. So IF his intention (by listing the dial indicator) was to do this, Fine and I agree it Would work.

If that was Not his intention, then as stated Several times previously, Not going to Work with Any Degree of ACCURACY!

Again, he states it simply as, And in the example I gave, using a cam centerline of 112 degrees, half of that value would be 56 degrees. So his method sounds good in theory and would work.

But I don't see how to accomplish it. In order to loosen the bolts (so the cam can be turned) the cam degree wheel must be removed. And with a wrench on the cam bolt, it can't be put back until the cam is turned to the proper place and the bolts tightened again. So, how do you know how far to turn the cam? Without the degree wheel on the cam, there is no reference.

Add to that the fact that there is valve spring pressure acting on the lobe, because the valve maybe somewhat or fully open. What is to keep the cam from snapping into a "relaxed" position as soon as the sprocket bolts are loosened?

His method sounds good when it is stated in very broad simple terms (as he is apt to do). But when we start to go through all the actual steps required, thinking through what would happen or need to happen at each stage, then his procedure breaks down, and proves impossible to do.

Barry

Let's get something straight, I Did NOT Dream about this solution to say "Hey Everybody, Do it THIS way!" lol

I am Simply Stating that IT IS POSSIBLE, for something Along the lines of what Asa was describing, to work. I am in No means saying it would be Easier or to Even Attempt it! lol

Simply for the sake of argument and to Show Asa that I AM open to Any Ideas and that By No means did any of my earlier post mean to "put down" his theory without thinking it through.

So, with the added pieces (detail) to the puzzle, I Can see it. Will I Ever Take Any more Time to attempt to Prove it in the real World.........NO.

[sdac guy]

If that was Not his intention, then as stated Several times previously, Not going to Work with Any Degree of ACCURACY!

That was my feeling too. Since his intention was to not use the book method, but suggest an alternative to the book method, I pretty much assumed he was not going to use the book method to really determine the cam CL.

Let's get something straight, I Did NOT Dream about this solution to say "Hey Everybody, Do it THIS way!" lol

I am Simply Stating that IT IS POSSIBLE, for something Along the lines of what Asa was describing, to work. I am in No means saying it would be Easier or to Even Attempt it! lol

Simply for the sake of argument and to Show Asa that I AM open to Any Ideas and that By No means did any of my earlier post mean to "put down" his theory without thinking it through.

So, with the added pieces (detail) to the puzzle, I Can see it. Will I Ever Take Any more Time to attempt to Prove it in the real World.........NO.

And I agree wholeheartedly. His method, in concept, would work. But when I imagine the tools in my hands, and then what to do next, that is where it falls apart.

The suggestion Dr. Johhny made about having the degree wheel at the back of the cam would solve a host of the problems I pointed out. However some heads have a cap there incorporated with the rear seal, so the end of the cam is not accessible. And also to note, that unless you mount the degree wheel facing the trans at that location, much of it would be hidden behind the head. And if it did face that direction, then the numbers would be in reverse direction as the cam turned clockwise from the front.

One other thing to point out, is that with ASA'a method of centerlining the cam, it would be very difficult to verify it is actually installed spot on the intake lobe centerline. While using the book method it is just one more time around noting the marks on the degree wheel and doing the math.

Barry

[bakes]

My brain hurts now !!!!

[4 l-bodies]

Here is a couple more actual camshaft degree measurements I took years ago. This was done on uncut cylinder head, with .006 cut from deck of block to get flat. Standard .072 thick headgasket. Sorry this got compressed when I copied from MS word document. Looked great on preview until I posted it.

86 Slider turbo camshaft
From low mile 86 GLHS. No noticeable wear. # 618 casting. T stamped in end..New follower used. Zero lash.



Intake: Exhaust:
-Duration @ .020 238.5 232

- Duration @ .050 218.5 214
- Duration Advance ----- -----
-Overlap @ .050 +1 degree
-Intake centerline 110.5 Exhaust CI 104.5 retarded 3°
- Lift at Valve .430 .430
- Open @ .050 1.5 ATDC 31 BBDC
- Close @ .050 40 ABDC 2.5 ATDC
- LSA 107.5



89 Roller turbo camshaft
2.5 turbo 1. New follower used. Zero lash.

Intake: Exhaust:
-Duration @ .020 234 231

- Duration @ .050 212 209.5
- Duration Advertised ---- -----
-Overlap @ .050 -17 negative
-Intake centerline 112.5 Exhaust CI 113.5 advanced .5 degree
- Lift at Valve .433 .433
- Open @ .050 5.5 ATDC 41 BBDC
- Close @ .050 37.5 ABDC 11.5 BTDC
- LSA 113

[turismolover22]

You will have to open it up in excel, then more than likely copy and paste it, and when pasting, or copying with the "txt only" option. It should keep spaces and will place it in like a normal copy-paste jobbie.

[wheming]

Ok here's my motivation in following and partipating in this discussion. .. and this is the question I hope to have answered.
Background:
Aftermarket camshaft gets installed in a newly rebuilt engine by a very reputable builder, and is properly centerlined during build. Adjustable cam gear is used. ...skip forward to car delivered and is running and enjoyed with no issues.

Later down the road, customer has a timing belt failure.
How does the person verify proper cam alignment on new belt install? Does the entire centerlining procedure need to be performed?
Is it as simple as lining up the factory marks at that point? If there was any advance or retard (adjustable cam sprocket at any position other than 0) would you still just set the cam & crank at the factory marks and install the new belt from there? (Though you may not have the belt teeth immediately line up due to any adv/rtd on the cam gear.)

So mainly, is the centerlining procedure to accurately indicate the timing mark on the cam gear for future belt replacements?

Thanks for the discussion.

[BoostedDrummer]

It's the 15th, I'm ready for some performance feedback!

[sdac guy]

Ok here's my motivation in following and partipating in this discussion. .. and this is the question I hope to have answered.
Background:
Aftermarket camshaft gets installed in a newly rebuilt engine by a very reputable builder, and is properly centerlined during build. Adjustable cam gear is used. ...skip forward to car delivered and is running and enjoyed with no issues.

Later down the road, customer has a timing belt failure.
How does the person verify proper cam alignment on new belt install? Does the entire centerlining procedure need to be performed?
Is it as simple as lining up the factory marks at that point? If there was any advance or retard (adjustable cam sprocket at any position other than 0) would you still just set the cam & crank at the factory marks and install the new belt from there? (Though you may not have the belt teeth immediately line up due to any adv/rtd on the cam gear.)

So mainly, is the centerlining procedure to accurately indicate the timing mark on the cam gear for future belt replacements?

Thanks for the discussion.

I've always used the offset cam keys, so I am unfamiliar with any of the adjustable cam sprockets. But, once the cams were centerlined, my stock sprockets still lined up as in the stock setup. That is, at TDC, the dots lined up on the lower sprockets, and my cam sprocket was lined up where the cam cap to head junction was centered in the holes on either side of the sprocket.

I know this doesn't answer your question, but I am relaying this to show that the cam is what is adjusted in the centerlining procedure, not the sprocket.

If the adjustable sprocket doesn't have any marks to use when installing it, as the stock sprocket does, then I would say, that to assure it is installed correctly, the centerlining procedure should be used. And it should be fairly straightforward to see if it off a tooth or two.

Barry

[acannell]

I am Simply Stating that IT IS POSSIBLE, for something Along the lines of what Asa was describing, to work. I am in No means saying it would be Easier or to Even Attempt it! lol

Simply for the sake of argument and to Show Asa that I AM open to Any Ideas

Rob, I must admit, I am pleasantly surprised to see how you actually walk the walk when it comes to putting your ego aside. I don't think I have seen this before on an internet forum, seriously.

Shelbyvnt2 its good to see you are awake and thinking.

And knownenemy, your thoughts on being teachable are well said!



Once people give themselves permission to think for themselves, the value of their tools and knowledge, and most importantly, their confidence about approaching and solving problems, SKYROCKETS. Rob, you have clearly reached the highest echelon of this. Clearly you are driven by the principle of truth above all else.

If all it took to win races and go faster was to RTFM, we'd have alot more 10 second chargers and 8 second G-bodies. But its not, and so there aren't. Those guys did not get there by connecting the dots. An open mind goes a LONG way.


"Doubt everything or believe everything: these are two equally
convenient strategies. With either we dispense with the need for
reflection." - Henri Poincare

[4 l-bodies]

Ok here's my motivation in following and partipating in this discussion. .. and this is the question I hope to have answered.
Background:
Aftermarket camshaft gets installed in a newly rebuilt engine by a very reputable builder, and is properly centerlined during build. Adjustable cam gear is used. ...skip forward to car delivered and is running and enjoyed with no issues.

Later down the road, customer has a timing belt failure.
How does the person verify proper cam alignment on new belt install? Does the entire centerlining procedure need to be performed?
Is it as simple as lining up the factory marks at that point? If there was any advance or retard (adjustable cam sprocket at any position other than 0) would you still just set the cam & crank at the factory marks and install the new belt from there? (Though you may not have the belt teeth immediately line up due to any adv/rtd on the cam gear.)

So mainly, is the centerlining procedure to accurately indicate the timing mark on the cam gear for future belt replacements?

Thanks for the discussion.

Wayne,
As Barry stated, if using adjustable cam keys instead of adjustable cam sprockets the stock cam pulley will be centerlined properly if lined up using the FSM procedure (line up the arrows on cam sprocket with the centerline of cam cap). At that point, only the camshaft has changed relative position.

However, if using adjustable cam gear (esp. the newer Fidanza ones) it is a little easier to install incorrectly. On the later Fidanza sprockets, they do not have arrows like the factory sintered sprocket and to add to that, they have made two rather large holes in the sprocket which makes it tougher to visualize when trying to locate or center the cam between casting cap lines. With the Fidanza sprocket, the outer part of gear stays in the same place, while the camshaft and inner part of sprocket rotates (advancing or retarding), making the idea of centerlining it to the camshaft caps inaccurate.

I have noted many times on these forums that not all Fidanza sprockets are truly cut as accurately as the factory sprockets. I have found some to be as far off as 4° both retarded and advanced from where they should be. I have my own speculation as to why this is. Just to add to this confusion even more, note that there were also several different sprockets the factory used that altered the keyway position, but that is another can-o-worms (lol). So if you are using the same camshaft with the same adjustable cam sprocket and only the belt has changed, then you should be able to put camshaft back in without altering centerline. Note that if deck of block or surface of head was machined, or replacement of headgasket was thinner, then camshaft will be retarded slightly from where it was prior.

You may find it easier to line up Fidanza sprocket, by making a note where camshaft is advanced or retarded, then loosen bolts and bring it back to what is Fidanza considers the zero mark (neither advanced or retarded) is. Line up centerline of sprocket with centerline of caps, and then readjust sprocket back to where your engine builder originally set the sprocket. If you still seem unsure about whether you are getting the Fidanza sprocket lined up with centercap of head, if you have another stock cam sprocket (that is the correct sprocket for your application), you can use that to line marks and arrows up properly, and then slip that off and install Fidanza sprocket on camshaft, then install belt and tighten.
Todd

[wheming]

Thanks for your replies Barry and Todd. Although I hate to muddy up this discussion with my own challenges I felt it was relative to the discussion.
After focusing on properly centerlining the aftermarket cam, by the builder/tuner one would really want to ensure they don't mess that up during future maintenance.
Personally I'll be using the Fidanza adj gear, but still have the factory one as well. I didn't know if one could maintain the setting once the belt comes off. I had heard of the fidanza gears being off significantly as well. They only allow for +/- 12 deg adjustment according to the printed reference marks.
I also didn't know if it were to be probable one might need to use both the offset cam keys with the adjustable gear. If the cam tolerance and required centerline might put you right at the edge of adjustment with no way to fine tune adjust later. (If that makes sense.)

Granted my discussion comes from the standpoint of no first hand experience 1) centerlining a cam, and 2) using an adjustable cam gear.

I did make the same observations of the fidanza gear, that being the alignment holes are much larger. Spotting the holes against the cam cap is already difficult enough in most TM's but the vans are worse.
I just want to be educated about how to maintain the build specs on future belt replacements when the time comes.
Thank you again for your thoughts on the matter. :thumbup:

[4 l-bodies]

Thanks for your replies Barry and Todd. Although I hate to muddy up this discussion with my own challenges I felt it was relative to the discussion.
After focusing on properly centerlining the aftermarket cam, by the builder/tuner one would really want to ensure they don't mess that up during future maintenance.
Personally I'll be using the Fidanza adj gear, but still have the factory one as well. I didn't know if one could maintain the setting once the belt comes off. I had heard of the fidanza gears being off significantly as well. They only allow for +/- 12 deg adjustment according to the printed reference marks.
I also didn't know if it were to be probable one might need to use both the offset cam keys with the adjustable gear. If the cam tolerance and required centerline might put you right at the edge of adjustment with no way to fine tune adjust later. (If that makes sense.)

Granted my discussion comes from the standpoint of no first hand experience 1) centerlining a cam, and 2) using an adjustable cam gear.

I did make the same observations of the fidanza gear, that being the alignment holes are much larger. Spotting the holes against the cam cap is already difficult enough in most TM's but the vans are worse.
I just want to be educated about how to maintain the build specs on future belt replacements when the time comes.
Thank you again for your thoughts on the matter. :thumbup:

Wayne,
If all your doing is maintenance, the spring pressures will hold the cam in place no problem. With that in mind, it is the aux. shaft that will move just looking at it (lol). 12° is actually a huge amount of adjustability. 24° crank degrees. A full tooth is only 9 degrees, so it you need more than 12°, you have other problems (lol).
I have had only one engine that I had to intentionally move the cam sprocket a tooth off to get fidanza pulley to have some adjustability left after centerlining. It was a combo of stacking of events, cam centerline ground WAY off, Fidanza pulley off 4°, and head and deck of block having been resurfaced. Then after a short amount of time, one lobe on that camshaft went bad from being over-hardened. So that cam was removed anyway. The next camshaft I put in only needed a small correction to centerline properly, so the majority of issue was the improperly ground camshaft.
Todd

[Shadow]

Cam info provided by Bakes;

[Shadow]

Couple more, Not 8v but may be of use to some;

[bakes]

I cant take any credit for any of the charts i just found them on the net years ago , Who ever did the work i tank you

[Shadow]

I cant take any credit for any of the charts i just found them on the net years ago , Who ever did the work i tank you

Yeah I recognized them from years ago when I did all of My Cam research, came across them a few times. Some interesting stuff in there, Really Unfortunate that there is NO correlating Data to performance gain/ change

Somethings to consider going forward;

When I first got involved in turbocharged platforms I was Very Fortunate. While most others seemed to think that a Turbo motor was a completely Different beast, my Brother and I Didn't. We believed that IF you took the most Efficient N/A build and put a turbo on it, it would Also make the Most Efficient turbo motor.

For Years This very misconception has held people back who would otherwise have had Much Less issue when Choosing the right combo for their builds. Also, it was something you could hardly talk about, because everyone would Jump on you and tell you that it's "Turbo" so completely different and Not worth mentioning anything N/A in relation. lol

This is also the reason you can have several different Flavours of builds that all Seem to do well (confusing) because, as I stated several years ago, None of them are Efficient enough to show the difference. That is to say, Boost can be a nice bandaid and can "Mask" small differences like underported head/ overported head ect. So until you see the Whole pkg done Correctly, it can be Very difficult to determine Which build is the Real Deal.

Anyway, here we are, 10 years later and I would Hope that Most have come around to the Same conclusion. (will make it a lot easier to follow what IS going to come out in this thread) IF you're one who is still in doubt, Maybe this will be the turning point for you

I am going to try harder than Ever, to bring things down to the simplest level of understanding that I can. If you have a Q, go ahead and ask as I believe the Right individuals Are present and this IS the right time for this all to come out.

When I speak of a "Model" turbocharged build, I will be referring to a platform that has 1:1 pressure diff or Better. This IS an Important piece of the puzzle, when it comes to over-all Understanding as you will soon see. This also plays into what I was Trying to explain to Simon when he asked me about Boost effect on Cam selection. The amount of boost you choose to run has Zero to do with Cam selection, but the amount of Drive pressure is a Different story. Somehow Simon confused "Boost" for "Intake manifold design" and it was not worth pursuing at that time, but with greater overall understanding it should be doable now.

For those who have done Cam testing and centerline installed cams as well as checked valve events ect. Do Any of you have any correlating Data in Real World performance gains? (ie. Dyno graph showing BtB runs with Powerband Gain ect?)

It's important to define this early, as All the Data and Info on paper in the World means ZERO if it doesn't correlate to anything REAL. Just like all of the Cam info I just posted up for Bakes. It's interesting to look back on, but even IF we had All of the valve events ect, it really means Nothing without any Real Proven Testing

This is why I was never concerned about valve events ect when it came to the F4 cam in the Charger. At that point it was Meaningless, The Cam Worked.......PERIOD! ANYONE who Can't understand that THIS is the most Important Info, the END result, will be lost in all of this as most have been all this time

The only time any of the other info comes into play is in going one step Further. (ie. The F4 Works and I Know exactly what it did to peak HP and TQ and now I want to try and go Higher in RPM ect) THIS is where I would need to Know all of the other specs in order to take the Next step in an Informed manner.

So, to those who believe that the F4 just happens to work in the Chargers build, with Big Boost ect. but may not work in theirs I will simply say this; ANY other build that is operating at 1:1 Pressure Diff will have the same type of powerband (RPM) gain. The Cam is a Mechanical device and could care less how much boost is in front of it. So it's only the Exhaust Pressure that can determine whether you should go to a different profile. (more LSA ect)

Now, Intake/ Exhaust Pressures aside, there Are many Other factors in selecting a cam, but I figured we should get rid of the "Boost" MYTH first! (since it Should give a Clearer picture of Everything else, once you can "see" it)

[83scamp]

When I first got involved in turbocharged platforms I was Very Fortunate. While most others seemed to think that a Turbo motor was a completely Different beast, my Brother and I Didn't. We believed that IF you took the most Efficient N/A build and put a turbo on it, it would Also make the Most Efficient turbo motor.

For Years This very misconception has held people back who would otherwise have had Much Less issue when Choosing the right combo for their builds. Also, it was something you could hardly talk about, because everyone would Jump on you and tell you that it's "Turbo" so completely different and Not worth mentioning anything N/A in relation. lol

OK, Rob, so now I'll bite into this since the discussion is heading more my direction. Since my combo is N/A, do you think an F4 cam would work in it, or is the F4 dialed in for a boosted setup? I'm currently running a "767" cam, and it makes great power across the entire RPM range. I'd like to go bigger, but I'm afraid it will get too "peaky" for street driving. Maybe something milder, like an F2 or F3 would work?

[shelbyvnt2]

It's the 15th, I'm ready for some performance feedback!

What he said!!!!^^^^^^^^^^^^^

[Shadow]

OK, Rob, so now I'll bite into this since the discussion is heading more my direction. Since my combo is N/A, do you think an F4 cam would work in it, or is the F4 dialed in for a boosted setup? I'm currently running a "767" cam, and it makes great power across the entire RPM range. I'd like to go bigger, but I'm afraid it will get too "peaky" for street driving. Maybe something milder, like an F2 or F3 would work?

IF the F4 IS indeed 116 LSA then No, I wouldn't waste my time even considering it for an N/A application. With all of the N/A cams that were available through MP I have to believe someone out there has a stockpile!

This is where we Really Dropped the Ball as a community, and when it comes to performance with This platform. (I include Myself in this) We Should have Married ourselves to the IMSA racers and looked for All info the N/A 8v's that were running what? 9000rpm? (rumoured anyways)

This would have been Great info to transfer over to a Boosted motor. Just look at the cams that were available back in the day, including the offerings from LRE and you can see just how far behind we got from Blindly Believing "Myths".

Remember, The Simplest way to make More Power is to turn Higher RPM. (long as you Know how to make it Live at Higher RPM)

Also, and to clarify on the F4. I am Not saying it is the Best cam you could Ever run in one of these mtrs. It is a mild to mid cam at best, and really Shouldn't be listed as a "race cam". lol (and this Shows our mind set) But along with the Taft S3, It WORKS! They are the ONLY TWO Cams that I have BtB Feedback on in the real World (By Highly Reputable individuals) and That's Why I Speak of them with High regard.

Everything else out there is "Unproven" AFAICS. Take it for what it is..........

[83scamp]

Thanks Rob, That is what I suspected, but I wanted to make sure.


As I said before, I love the MP 767 cam. It was originally listed by Mopar as a "race" cam, but it works very well on the street. It was the biggest hydraulic cam offered by Mopar, part of the reason I picked it. It seems to have a very broad power curve, and just gets better the more you rev. I've wound my 2.2 to 7K without issues. I'm sure it would go beyond that, but I really don't feel like abusing it.

Thanks again for all the info provided in this thread. It allows me to see all sides of the cam issues, and I hope it helps everybody be more informed about how to pick a cam...