Topic: When Installing a Performance Cam

[flatlander]

here's a step by step description that dave barbier wrote up:
http://forums.sohc4.net/index.php/topic,140833.msg1890649.html#msg1890649

he works on a 550 so you can skip what he says about the valve cover but the rest is true for you as well, and very clearly described.
if you are a bit nervous (which is understandable as it is a bit of a daunting and quite critical process) then take your time, do it calmly step by step, and measure everything three times. three times from scratch, i.e. remove your measuring setup and re-install it before repeating. if all three times the values are within the same ballpark (they will vary very slightly due to tolerances) then your'e good. if not then something went wrong on one or more of the attempts.

[grcamna2]

I purchased my cam degreeing kit(with Dale Walker VHS video)from APE in the mid 90's and it came with all what's needed to do the job;back then they used a VHS video tape,it also included the positive stop tools,dial indicator/magnetic base,degree wheel,etc.
I had nobody help me my first time and needed to watch the video and slowly take it step by step.

[PeWe]

Some thoughts to fill your head to get the feeling for it

Valve to valve clearance to be done before mounting the head. Use weak springs and assemble cam with 2 valves.
More important with oversize valves.

The F2/F3 heads need some real checking with some hot cams due to valve size and angle. 34/31mm is stock.

The other earlier heads (marked 300, 392) 32/28. Often 34/28, 33.5/28.5mm  when modified with std valve kits available.

Valve to piston checked when timing the cam.
Pistons with proper valve relieves and a not that high lifting cam nor long duration, NO problem.
A check is another detail to ensure proper timing.

I tighten the adjuster screw at least 2-3mm to feel if valve hits the piston at various crank position. This in the +/- 15* area around TDC.


I time cam at 0 lash to come close to the cam card numbers.
I have done at running lash by checking the open/close once again after 0 lash, now with lash.
These are the numbers that counts.

Difference depending on how steep the cam is grinded.
I saw around 3* difference on both open and close. Less duration with lash.  I think that was  a CX7 cam.

0 lash timing need adjuster to be tightened until you can detect a valve  movement of about 0.01-0.02mm. This to overcome the play in rocker arm.
I time with only rockers on Cyl 1. When ready all the others to go on.

I have seen on both my CB750 that true TDC is correct when advancer is in its most counterclockward position. T will then line up correct with case mark.

My modified K6 has got an alternative case mark (3mm after stock). This since I rotate the crank by using the nut on ignition side.
Advancer must then sit in its clockward position. It will otherwise end up there while rotating the crank.
I use the kickstarter most if the time. The advancer has a rather wide play when loose.

I time cam with engine in frame thanks to frame kit.

If cam need to be adjusted for more advance, crank need to be moved backwards.
This when valve is opened as it should. I usually time at 1mm opened/closed valve (0.04").
I roll bike backwards with gear in.
No problem if it will move a little bit too much so it open 1mm at 35* BTDC instead of targeted 26-27*. Then easier to untighten the cam bolts, hold cam in place with a spanner on cam end 12mm, rotate crank clockwise until it land at needed number like 26-27. Better with higher that can be adjusted again.

Rotate engine to check when open 1mm again, continue to rotate until max lift, count backwards to not miss when it is closing down to 1mm lift and note those numbers.

Now you have the open, max lift and close numbers to compare with cam card.

It is better if IN will open 2-3 degrees earlier than later.

My 125-75 cam did not like 1.5* later than cam card. Less pressure.

Now check exhaust timing.
When you have IN and EX numbers you can compare their (balance) how much it differs from cam card that differ some. It depends on the grinder.
Cams that have equal numbers on EX as IN but inverted is easier.
Like:
IN open at 25*, close at 55*
EX open at 55*, close at 25*.

Your CX11 seems to be close to the Kenny Harmon F cam.
So in and ex are not like that.

I should focus to time IN to open as cam card say at 0.05" (1.25mm) lift.
Then see when it close. If IN will close later than cam card, I should advance the cam so IN close will be closer to card numbers. 
But still  advance within 2-3* range compared to card.

The lash on my cams usually IN: 0.10mm,  EX: 0.15mm.
0.004/0.006"
This means that the running lash will advance cam a little when lash is more on ex than in.

DP315 cam must have its huge lash (double up) 0.3 mm (0.012"). If like other cams it will get a huge overlap that throw compression thru the window.
Even if lift and duration  increase, the power will be lower.
I have tested it on road and compression tester.
That cam had close valve to valve clearance on a ported K6 head. 1mm.
34mm in, 28 mm ex valves.
I guess my 392 head with 33.5/28.5mm valves get same clearance.

I think Megacycle 125-20 cam had at least 1.5mm valve to valve.
That cam has a similar design as KH F. Ex open/close a litte bit special compared to other cams.

Take your time when timing.
I should time at 0 lash to verify in/open numbers and lift vs card.
Then adjust adjuster to running lash and note those numbers and see how cam will land.

It is only 1 cam so if you advance IN, EX will follow.
When both will differ from card, adjust so the balance between in and ex will be like  the card, if IN open 2-3 degrees earlier can be good, though.

Remember
- No plugs in.
- Do not rotate crank backwards by using the nut on ignition side.
- Cam chain tensioner to be mounted during timing.

- Check Valve- Piston clearance around TDC .

Tighten when crank is in correct position. Release, move crank and test again ... +/- 20* around TDC must cover it.

When you have done it well one time, note the numbers and save.
If you need to take it apart, enough to check IN valve quick when timing again.

The timing numbers differ a few degrees if you have timed with not that tightened adjuster to reach 0 lash.
Max lift less as well.

I had to open my K6 engine last winter.
Cam timing was good. So I marked the cam and sprocket with punch marks. The self punching tool by pressing, no hammer. Used marker pen too.

I set the sprocket to align the marks when I assembled it.

Timing was spot on as before with good behavior on road and dyno.
I only checked it, no need to adjust, recheck and maybe adjust again....

[dragracer]

It's not rocket science.  So please don't be discouraged because it's easier than it first appears.  The best video I ever watched was by Dale Walker. I borrowed it from a friend and then had to source a used VHS player to watch it. I'm fairly certain you could find it via Google by electronic download means. You'll need to source the correct tools. Schnitz Racing sells a complete cam degreeing kit and it has a video. Or you can go down to your local Harbor freight tools,  they have the magnetic base, and dial indicator.  Jegs Racing or Summit have degree wheels in different diameters along with piston stops. I prefer using the positive stop method. In fact I make my own using an old spark plug. I break all the porcelain out, cut off the tip and put the proper length machine screw through it to make a stop. You then just need to fabricate your own base plate  to mount the magnetic base to the engine.

[Ellz10]

So I ended up buying the Dale Walker video. I was really hoping I could purchase it electronically, but it seems that isn't an option anywhere. So I'll wait for that to arrive and watch it and judging by the comments of everyone who's watched it, I should be able to figure it out. If I can't, I'll be back with questions!

Does anyone know if he goes over valve to piston clearance in the video?

[Ellz10]

So one question I do have - and this is based loosely on my understanding of how the degree-ing of the cam works - is this:  So I insert my piston stop, then mount my degree wheel. Then I fashion some copper wire or such to point down on the degree wheel. Now am I setting the wheel up to where the wire is pointing at ZERO (0) or somewhere else?  Now then, I slowly turn the crank until it lightly hits the piston stop and then record the number on the degree wheel. Then go in reverse until it again lightly hits the piston stop, then record that number. Sound about right so far? Now if the two numbers, for mathematical sake, are let's say 50 and 30, I would add them together to get 80 and then divide by 2 to get 40. Now my question is what do I do next? How do I go about making it 40 degrees when I turn the crank forward and reverse and not the 50 and 30 (or whatever the numbers may be)?

[MRieck]

So one question I do have - and this is based loosely on my understanding of how the degree-ing of the cam works - is this:  So I insert my piston stop, then mount my degree wheel. Then I fashion some copper wire or such to point down on the degree wheel. Now am I setting the wheel up to where the wire is pointing at ZERO (0) or somewhere else?  Now then, I slowly turn the crank until it lightly hits the piston stop and then record the number on the degree wheel. Then go in reverse until it again lightly hits the piston stop, then record that number. Sound about right so far? Now if the two numbers, for mathematical sake, are let's say 50 and 30, I would add them together to get 80 and then divide by 2 to get 40. Now my question is what do I do next? How do I go about making it 40 degrees when I turn the crank forward and reverse and not the 50 and 30 (or whatever the numbers may be)?

The only caveat is with larger valves and cams the intake valve can hit the dead stop and bend the valve....I mentioned this earlier as it happened to Jerry RX using a 34 mm intake valve. You can put the piston at TDC....back it of 30 degrees or so....screw in the piston stop and slowly bring to to TDC and get your reading...ie 23 degrees BTDC. Unscrew the stop....turn engine in the opposite direction until about 30 degrees after TDC....screw the stop in and slowly turn counter clockwise until it stops ie 26 degrees ATDC. Subtract 23 for 26 and you get 3 degrees. Divide that by 2 and get 1.5 degrees. Move your needle to 24.5, pointer...what ever you want to call it...and you will be at absolute TDC. I tell you to pull the TDC tool out becuase the nose is to thick and will catch on the intake valve......Just ask Jerry.

[Jerry Rxman Griffin aka MuthaF'er]

Oh yeah!!

[Ellz10]

So one question I do have - and this is based loosely on my understanding of how the degree-ing of the cam works - is this:  So I insert my piston stop, then mount my degree wheel. Then I fashion some copper wire or such to point down on the degree wheel. Now am I setting the wheel up to where the wire is pointing at ZERO (0) or somewhere else?  Now then, I slowly turn the crank until it lightly hits the piston stop and then record the number on the degree wheel. Then go in reverse until it again lightly hits the piston stop, then record that number. Sound about right so far? Now if the two numbers, for mathematical sake, are let's say 50 and 30, I would add them together to get 80 and then divide by 2 to get 40. Now my question is what do I do next? How do I go about making it 40 degrees when I turn the crank forward and reverse and not the 50 and 30 (or whatever the numbers may be)?

The only caveat is with larger valves and cams the intake valve can hit the dead stop and bend the valve....I mentioned this earlier as it happened to Jerry RX using a 34 mm intake valve. You can put the piston at TDC....back it of 30 degrees or so....screw in the piston stop and slowly bring to to TDC and get your reading...ie 23 degrees BTDC. Unscrew the stop....turn engine in the opposite direction until about 30 degrees after TDC....screw the stop in and slowly turn counter clockwise until it stops ie 26 degrees ATDC. Subtract 23 for 26 and you get 3 degrees. Divide that by 2 and get 1.5 degrees. Move your needle to 24.5, pointer...what ever you want to call it...and you will be at absolute TDC. I tell you to pull the TDC tool out becuase the nose is to thick and will catch on the intake valve......Just ask Jerry.

Ugh, just when I thought it couldn't get any more complicated...   


Wait.... I need to have the rockers installed BEFORE I degree my cam..?

[PeWe]

No rockers installed where you use the piston stop will save you from bent valves.
This is to determine the true TDC. ( Set degree wheel to 0)

Rockers on cyl 1 only for timing,  check with piston stop on cyl 4.

Mount the other rockers after you have timed cam on cyl 1.

I have verified TDC a few times on my K6 so I do not use piston stop anymore.
Set advancer where I know it will line up correct with stock case mark or my alternative case mark.

Better to turn crank some extra to know it will be correct.
My local tuning shop had marked cam and sprocket so I could assemble it correct in the 80's.

I had to learn the timing process much later, 2013 after refurbish and new cam.

New pistons that probably got their break-in during cam timing, CX-7 cam

I did it numerous times, noted the result and repeated until I got same values 3 times after each other so I was sure to have done it correctly, not only done it
I checked all 4 then. Not same values on all 4.
Open, max lift and close.

I did the same later on when I changed cam back to my old Action Fours cam. That one had equal values on all 4. Open/ close and lift. Equally worn too.

Training had made me to achieve same measurements too, not only better cam grinding of the AF cam.

The dial indicator must sit stable, not on a flexible plate that will give flexing numbers.

I helped a friend to time a similar cam as yours for not long ago, KH F. Really irritating when the indicator clock needle vibrated and gave different numbers.

[HondaMan]

So one question I do have - and this is based loosely on my understanding of how the degree-ing of the cam works - is this:  So I insert my piston stop, then mount my degree wheel. Then I fashion some copper wire or such to point down on the degree wheel. Now am I setting the wheel up to where the wire is pointing at ZERO (0) or somewhere else?  Now then, I slowly turn the crank until it lightly hits the piston stop and then record the number on the degree wheel. Then go in reverse until it again lightly hits the piston stop, then record that number. Sound about right so far? Now if the two numbers, for mathematical sake, are let's say 50 and 30, I would add them together to get 80 and then divide by 2 to get 40. Now my question is what do I do next? How do I go about making it 40 degrees when I turn the crank forward and reverse and not the 50 and 30 (or whatever the numbers may be)?

Here's something VERY, VERY important you MUST know about turning that crankshaft on the CB750 SOHC engine:
You MUST use the alternator rotor bolt, NOT the big nut by the points, to turn the crankshaft. If you use the points-side nut, you WILL (100% guarantee) bend the spark advancer's shaft. Then, when you try to set spark timing, you will find the timing jumping all over the place, back-and-forth, especially on the 2-3 side. It won't matter if you use electronics or points, this WILL happen. Then you will be faced with having to straighten the advancer shaft again, which is why I spent some time explaining how to do it in my book. It is a painful thing to have to do, especially twice.

[Ellz10]

So one question I do have - and this is based loosely on my understanding of how the degree-ing of the cam works - is this:  So I insert my piston stop, then mount my degree wheel. Then I fashion some copper wire or such to point down on the degree wheel. Now am I setting the wheel up to where the wire is pointing at ZERO (0) or somewhere else?  Now then, I slowly turn the crank until it lightly hits the piston stop and then record the number on the degree wheel. Then go in reverse until it again lightly hits the piston stop, then record that number. Sound about right so far? Now if the two numbers, for mathematical sake, are let's say 50 and 30, I would add them together to get 80 and then divide by 2 to get 40. Now my question is what do I do next? How do I go about making it 40 degrees when I turn the crank forward and reverse and not the 50 and 30 (or whatever the numbers may be)?

Here's something VERY, VERY important you MUST know about turning that crankshaft on the CB750 SOHC engine:
You MUST use the alternator rotor bolt, NOT the big nut by the points, to turn the crankshaft. If you use the points-side nut, you WILL (100% guarantee) bend the spark advancer's shaft. Then, when you try to set spark timing, you will find the timing jumping all over the place, back-and-forth, especially on the 2-3 side. It won't matter if you use electronics or points, this WILL happen. Then you will be faced with having to straighten the advancer shaft again, which is why I spent some time explaining how to do it in my book. It is a painful thing to have to do, especially twice.

I guess I better go buy a new shaft now then. I've been turning the crank the whole time using the big nut on the points.


Edit:  Just snagged one. On the off chance mine isn't bent, well now I'll have a spare.

[PeWe]

Spark plugs out when turning crank?
Probably OK when it rotate by ease.
If that stud is bent, possible to make it straight again. With a hammer where it wobble.
There are posts about it.

Rotate engine backwards not good since starter motor will add some resistance.
You'll see if ignition will act strange not possible to set equally.
If 1:4 and 2:3 look sharp with timing strobe lamp fed by an external battery for sure.

I have timed cams several times when engine sit in frame, not taken all apart and assembled on the bench.

Remove alternator cover and maybe the shifter cover beside, too much complications

7 cam timings  in my K6 since Sept 2020
3 different cylinders, 3 different heads and 3 different cams.
1 cylinder tested with 3 different cams within a few days last summer.

Then add all other years..... Changing cylinders, heads and try different cams.

It idles nice and evenly despite the torture . I have rotated a lot with kickstart too  with thoughts to the advancer    stud.

One thing I have noticed.... Higher lifting cam with harder valve springs need thread inserts in the cam holder threads in head.
I have Wurth Time-serts in all threads holding the cam holders and cam. They are all glued with Loctite 272 (red). Carefully cleaned with acetone before.

Studs sealed with Permatex high temp thread sealant when mounted into the thread insert when cured.

Other side where stud hole enter the spark plug cavity, sealed with JB Weld just for sure.
Rubber coins under cam holders sealed against head.
Hermetite Golden for many years ago, when no longer available, Hylomar (blue), last years Permatex Aviation no 3. Last times high temp black silicone that is not as messy and creeping as Permatex Aviation.
Hondabond or Threebond 1184 are really messy and sticky. Tried that too.
Fine for cases.

One head looked like stud threads were OK.  All other fixed.
But last time I looked at that head I noticed the typical radius of alu close to one stud as first sign when threads give up.
That head has almost all other threads refurbished with time serts, valve cover included.
Studs looked OK so I did not fix them. That head ran max 1500km.

So they will get stud threads fixed.

I do not tighten those very much. I learned the hard way that over 10Nm (7.4 ft lbs) is too much. Not fun when tighten and threads will give up.
I have a good torque wrench 1/4" sockets, 2.5-25Nm area.

I have fixed some with engine in frame. Cover all like a surgeon to ensure no burrs in engine.

I tighten max 6.6 ft lbs. 9 Nm despite inserts.
Those bolts are the harder ones, but head is still aluminium. Some heads have more porosity where threads are more fragile.
An old head can gave rotten threads even if std sorings and cam mounted.
A hard wrenching person might been there before or just rotten alum

I hope I do not need to take that engine apart for a long time now.
I had planned to replace my billet Megacycle 125-75 cam with a welded one called 125-70 later this year
If I get new welded rockers, OK

[Ellz10]

Does anyone have the DVD version of the Dale Walker cam degree video that they wouldn't mind selling or letting me borrow (I'll pay shipping there and back)?

[Tracksnblades1]

So one question I do have - and this is based loosely on my understanding of how the degree-ing of the cam works - is this:  So I insert my piston stop, then mount my degree wheel. Then I fashion some copper wire or such to point down on the degree wheel. Now am I setting the wheel up to where the wire is pointing at ZERO (0) or somewhere else?  Now then, I slowly turn the crank until it lightly hits the piston stop and then record the number on the degree wheel. Then go in reverse until it again lightly hits the piston stop, then record that number. Sound about right so far? Now if the two numbers, in for mathematical sake, are let's say 50 and 30, I would add them together to get 80 and then divide by 2 to get 40. Now my question is what do I do next? How do I go about making it 40 degrees when I turn the crank forward and reverse and not the 50 and 30 (or whatever the numbers may be)?

Most builders/tuners will use the factory’s timing mark 0 on the crankshaft or T for your engine.
Then set up your degree wheel to match the factory 0 or TDC marking. Then your initial degree
wheel/dead stop TDC method error will be minimal . Most of the videos already provided indicates
Doing this.

I’m not sure if Mr. Walker’s video illustrates your Honda SOHC engine. I’m thinking he uses
a DOHC but can’t remember. It shouldn’t matter though whether it’s a 1 cylinder 4 or 8 or more…

I would check your advancer pin, pin hole, and cranks shaft hole. If you have used the ignition
side as you indicated with the spark plugs installed,  it’s not “if” the shaft is bent as HondaMan stresses.
I’ve have seen the advancer pin sheared completely off as a result of turning the advancer nut by the owner
of a 836 12.5 kit with the spark plugs installed. PeWe has already posted here the excessive play
that exists in the factory Honda advancers. He offered his advise to achieve the desired Factory timing
When the point plate doesn’t seem to have enough travel to obtain it.

Whether you decide with lobe center or open and closing cam degreeing methods, I would try to become
familiar with the cam degreeing terminology. The methods for timing an asymmetrical cam vs a non symmetrical
camshafts and lobes may vary.  Some cams are ground with a built in 2-4* advance. Futher advancing one my not
be optimal. Some manufacturers will identify and provide both recommendations and specifications for the type purchased. Others assume you know and provide only the basic cam card.
 I prefer PeWe’s method, but understand the simpler and expedience of the centerline method for the novice or professional. As PeWe’s method will instantly identify any advances or retards as well as the stacking up of the factory’s machining tolerances. Especially if using all factory non adjustable components. However some are known to use a feeler gauge placed in the standard lash setting to check the 0 lash opening and closing degree times. Sometimes zero lash can be subjective and near impossible to measure or verify.

Like Drag Racer, “it’s not rocket science”,  pick the method you understand. And Like another posted  check it three times
and verify your results. Once fully assembled if you can roll it over easily by hand with no spark plugs, move to the next
Step….🎯😁

[Ellz10]

So one question I do have - and this is based loosely on my understanding of how the degree-ing of the cam works - is this:  So I insert my piston stop, then mount my degree wheel. Then I fashion some copper wire or such to point down on the degree wheel. Now am I setting the wheel up to where the wire is pointing at ZERO (0) or somewhere else?  Now then, I slowly turn the crank until it lightly hits the piston stop and then record the number on the degree wheel. Then go in reverse until it again lightly hits the piston stop, then record that number. Sound about right so far? Now if the two numbers, for mathematical sake, are let's say 50 and 30, I would add them together to get 80 and then divide by 2 to get 40. Now my question is what do I do next? How do I go about making it 40 degrees when I turn the crank forward and reverse and not the 50 and 30 (or whatever the numbers may be)?

Most builders/tuners will use the factory’s timing mark 0 on the crankshaft or T for your engine.
Then set up your degree wheel to match the factory 0 or TDC marking. Then your initial degree
wheel/dead stop TDC method error will be minimal . Most of the videos already provided indicates
Doing this.

okay this is very helpful! Perfect!


I would check your advancer pin, pin hole, and cranks shaft hole. If you have used the ignition
side as you indicated with the spark plugs installed,  it’s not “if” the shaft is bent as HondaMan stresses.
I’ve have seen the advancer pin sheared completely off as a result of turning the advancer nut by the owner
of a 836 12.5 kit with the spark plugs installed. PeWe has already posted here the excessive play
that exists in the factory Honda advancers. He offered his advise to achieve the desired Factory timing
When the point plate doesn’t seem to have enough travel to obtain it.

So I haven't installed my plugs at all yet in this rebuilt motor so I'm good there. Speaking of which, I need to buy some lol.

[Tracksnblades1]

So one question I do have - and this is based loosely on my understanding of how the degree-ing of the cam works - is this:  So I insert my piston stop, then mount my degree wheel. Then I fashion some copper wire or such to point down on the degree wheel. Now am I setting the wheel up to where the wire is pointing at ZERO (0) or somewhere else?  Now then, I slowly turn the crank until it lightly hits the piston stop and then record the number on the degree wheel. Then go in reverse until it again lightly hits the piston stop, then record that number. Sound about right so far? Now if the two numbers, for mathematical sake, are let's say 50 and 30, I would add them together to get 80 and then divide by 2 to get 40. Now my question is what do I do next? How do I go about making it 40 degrees when I turn the crank forward and reverse and not the 50 and 30 (or whatever the numbers may be)?

Most builders/tuners will use the factory’s timing mark 0 on the crankshaft or T for your engine.
Then set up your degree wheel to match the factory 0 or TDC marking. Then your initial degree
wheel/dead stop TDC method error will be minimal . Most of the videos already provided indicates
Doing this.

okay this is very helpful! Perfect!


I would check your advancer pin, pin hole, and cranks shaft hole. If you have used the ignition
side as you indicated with the spark plugs installed,  it’s not “if” the shaft is bent as HondaMan stresses.
I’ve have seen the advancer pin sheared completely off as a result of turning the advancer nut by the owner
of a 836 12.5 kit with the spark plugs installed. PeWe has already posted here the excessive play
that exists in the factory Honda advancers. He offered his advise to achieve the desired Factory timing
When the point plate doesn’t seem to have enough travel to obtain it.

**😁**
So I haven't installed my plugs at all yet in this rebuilt motor so I'm good there. Speaking of which, I need to buy some lol.

Assume nothing friend.
Verify x 3.

You really never know what the previous owner did..😁

[dragracer]

Before beginning the task, I'd suggest watching that video at least 3-4 times. Only watch in when you're relaxed so your mind isn't distracted. Once you begin the actual process, you'll be surprised at how everything will fall into place and your frustration level will be close to zero. Always remember,  there are members here that are more than willing to help either in this open thread, by private message or even by phone call/real time. Don't hesitate to reach out to someone because they're more than ready to lend a hand.

[Ellz10]

Before beginning the task, I'd suggest watching that video at least 3-4 times. Only watch in when you're relaxed so your mind isn't distracted. Once you begin the actual process, you'll be surprised at how everything will fall into place and your frustration level will be close to zero. Always remember,  there are members here that are more than willing to help either in this open thread, by private message or even by phone call/real time. Don't hesitate to reach out to someone because they're more than ready to lend a hand.

I will definitely watch it a few times. I've come this far, so I want to do it right. Over the past week I've really started to understand more and more so I'm hoping the video will make more sense than it would've 2 weeks ago. See, that's why I love this forum - all the good-hearted people who care about others and want to see them succeed in whatever they're doing with their builds. Thanks guys!

[Tracksnblades1]

Before beginning the task, I'd suggest watching that video at least 3-4 times. Only watch in when you're relaxed so your mind isn't distracted. Once you begin the actual process, you'll be surprised at how everything will fall into place and your frustration level will be close to zero. Always remember,  there are members here that are more than willing to help either in this open thread, by private message or even by phone call/real time. Don't hesitate to reach out to someone because they're more than ready to lend a hand.

I will definitely watch it a few times. I've come this far, so I want to do it right. Over the past week I've really started to understand more and more so I'm hoping the video will make more sense than it would've 2 weeks ago. See, that's why I love this forum - all the good-hearted people who care about others and want to see them succeed in whatever they're doing with their builds. Thanks guys!

So now that you’re understanding all of it, let’s pile it on… 😜

**⭐️Plagiarized from another OCD engine nerd…**⭐️👀

Asymmetric Lobes: In the past, both opening and closing sides of a cam lobe were identical. Most recently, designers developed asymmetrical lobes, wherein the shape of the opening and closing sides differ. Asymmetry helps optimize the dynamics of a valve train system by producing a lobe with the shortest seat timing and the most area. The designer wants to open the valve as fast as possible without overcoming the spring's ability to absorb the valve train's kinetic energy, then close the valve as fast as possible without resulting in valve bounce. There are many different theories about how to design the most aggressive, stable profile. Hydraulic lifters can provide quiet valve train operation only if the closing velocity is kept below a certain threshold. However, the opening velocity can be higher and still provide quiet operation. Almost all modern profiles have some symmetry.

Here the lobes differ from the opening side to the closing side. This allows the cam grinder to open the valve a one speed and close it at another. Here is where some cams are quite and some noisy. If the grinder has chosen to set the valve down slowly on the seat it will be a quieter cam than if the grind lets the valve down to quickly. Single pattern cams In the case of single pattern cams both the intake and exhaust lobe are the same. A cam can be asymmetrical and single pattern or symmetrical and single pattern. Dual pattern cams have different profiles on the intake and exhaust lobes. A cam of this type can be any combination of asymmetrical or symmetrical of profiles.

[Ellz10]

Before beginning the task, I'd suggest watching that video at least 3-4 times. Only watch in when you're relaxed so your mind isn't distracted. Once you begin the actual process, you'll be surprised at how everything will fall into place and your frustration level will be close to zero. Always remember,  there are members here that are more than willing to help either in this open thread, by private message or even by phone call/real time. Don't hesitate to reach out to someone because they're more than ready to lend a hand.

I will definitely watch it a few times. I've come this far, so I want to do it right. Over the past week I've really started to understand more and more so I'm hoping the video will make more sense than it would've 2 weeks ago. See, that's why I love this forum - all the good-hearted people who care about others and want to see them succeed in whatever they're doing with their builds. Thanks guys!

So now that you’re understanding all of it, let’s pile it on… 😜

**⭐️Plagiarized from another OCD engine nerd…**⭐️👀

Asymmetric Lobes: In the past, both opening and closing sides of a cam lobe were identical. Most recently, designers developed asymmetrical lobes, wherein the shape of the opening and closing sides differ. Asymmetry helps optimize the dynamics of a valve train system by producing a lobe with the shortest seat timing and the most area. The designer wants to open the valve as fast as possible without overcoming the spring's ability to absorb the valve train's kinetic energy, then close the valve as fast as possible without resulting in valve bounce. There are many different theories about how to design the most aggressive, stable profile. Hydraulic lifters can provide quiet valve train operation only if the closing velocity is kept below a certain threshold. However, the opening velocity can be higher and still provide quiet operation. Almost all modern profiles have some symmetry.

Here the lobes differ from the opening side to the closing side. This allows the cam grinder to open the valve a one speed and close it at another. Here is where some cams are quite and some noisy. If the grinder has chosen to set the valve down slowly on the seat it will be a quieter cam than if the grind lets the valve down to quickly. Single pattern cams In the case of single pattern cams both the intake and exhaust lobe are the same. A cam can be asymmetrical and single pattern or symmetrical and single pattern. Dual pattern cams have different profiles on the intake and exhaust lobes. A cam of this type can be any combination of asymmetrical or symmetrical of profiles.

Didn't realize this was a thing. I'll have to check mine in a little bit.

So when I look at my cam, will all the lobes have that little ramp or will it be half with the ramp and half normal?

[Tracksnblades1]

Before beginning the task, I'd suggest watching that video at least 3-4 times. Only watch in when you're relaxed so your mind isn't distracted. Once you begin the actual process, you'll be surprised at how everything will fall into place and your frustration level will be close to zero. Always remember,  there are members here that are more than willing to help either in this open thread, by private message or even by phone call/real time. Don't hesitate to reach out to someone because they're more than ready to lend a hand.

I will definitely watch it a few times. I've come this far, so I want to do it right. Over the past week I've really started to understand more and more so I'm hoping the video will make more sense than it would've 2 weeks ago. See, that's why I love this forum - all the good-hearted people who care about others and want to see them succeed in whatever they're doing with their builds. Thanks guys!

So now that you’re understanding all of it, let’s pile it on… 😜

**⭐️Plagiarized from another OCD engine nerd…**⭐️👀

Asymmetric Lobes: In the past, both opening and closing sides of a cam lobe were identical. Most recently, designers developed asymmetrical lobes, wherein the shape of the opening and closing sides differ. Asymmetry helps optimize the dynamics of a valve train system by producing a lobe with the shortest seat timing and the most area. The designer wants to open the valve as fast as possible without overcoming the spring's ability to absorb the valve train's kinetic energy, then close the valve as fast as possible without resulting in valve bounce. There are many different theories about how to design the most aggressive, stable profile. Hydraulic lifters can provide quiet valve train operation only if the closing velocity is kept below a certain threshold. However, the opening velocity can be higher and still provide quiet operation. Almost all modern profiles have some symmetry.

Here the lobes differ from the opening side to the closing side. This allows the cam grinder to open the valve a one speed and close it at another. Here is where some cams are quite and some noisy. If the grinder has chosen to set the valve down slowly on the seat it will be a quieter cam than if the grind lets the valve down to quickly. Single pattern cams In the case of single pattern cams both the intake and exhaust lobe are the same. A cam can be asymmetrical and single pattern or symmetrical and single pattern. Dual pattern cams have different profiles on the intake and exhaust lobes. A cam of this type can be any combination of asymmetrical or symmetrical of profiles.

Didn't realize this was a thing. I'll have to check mine in a little bit.

So when I look at my cam, will all the lobes have that little ramp or will it be half with the ramp and half normal?

The question is would you be able to see it with your eyes as the rocker arm and valve sees it.
Looking at your cam card the obvious…? It’s a dual pattern. The exhaust’s lift and duration is different than the intake’s.
I’m not sure you can tell by eye whether it has the more desirable (to some) asymmetrical opening and closing lobe profiles, or symmetrical lobe profiles. It would be a challenge to measure accurately enough and graph the actual lifts vs degrees of the opening and closing ramps to make that determination. Especially if the two ramp profiles weren’t radically different.
It was once believed for maximum efforts the opening ramp should open the valve as quick as possible within the springs ability to control it from being launched off of the desired lope profile. Then have a closing ramp that literally lets the valve free fall or close as fast as the spring could close it but at the very last moment, gently catch it and set it near the base circle ever so gently. All Theoretically of course. You’ve already bought your cam so this really don’t matter right now. It should help you understand why PeWe is worrying about averaging his observed errors of his installed cams opening and closing points.

[Ellz10]

Before beginning the task, I'd suggest watching that video at least 3-4 times. Only watch in when you're relaxed so your mind isn't distracted. Once you begin the actual process, you'll be surprised at how everything will fall into place and your frustration level will be close to zero. Always remember,  there are members here that are more than willing to help either in this open thread, by private message or even by phone call/real time. Don't hesitate to reach out to someone because they're more than ready to lend a hand.

I will definitely watch it a few times. I've come this far, so I want to do it right. Over the past week I've really started to understand more and more so I'm hoping the video will make more sense than it would've 2 weeks ago. See, that's why I love this forum - all the good-hearted people who care about others and want to see them succeed in whatever they're doing with their builds. Thanks guys!

So now that you’re understanding all of it, let’s pile it on… 😜

**⭐️Plagiarized from another OCD engine nerd…**⭐️👀

Asymmetric Lobes: In the past, both opening and closing sides of a cam lobe were identical. Most recently, designers developed asymmetrical lobes, wherein the shape of the opening and closing sides differ. Asymmetry helps optimize the dynamics of a valve train system by producing a lobe with the shortest seat timing and the most area. The designer wants to open the valve as fast as possible without overcoming the spring's ability to absorb the valve train's kinetic energy, then close the valve as fast as possible without resulting in valve bounce. There are many different theories about how to design the most aggressive, stable profile. Hydraulic lifters can provide quiet valve train operation only if the closing velocity is kept below a certain threshold. However, the opening velocity can be higher and still provide quiet operation. Almost all modern profiles have some symmetry.

Here the lobes differ from the opening side to the closing side. This allows the cam grinder to open the valve a one speed and close it at another. Here is where some cams are quite and some noisy. If the grinder has chosen to set the valve down slowly on the seat it will be a quieter cam than if the grind lets the valve down to quickly. Single pattern cams In the case of single pattern cams both the intake and exhaust lobe are the same. A cam can be asymmetrical and single pattern or symmetrical and single pattern. Dual pattern cams have different profiles on the intake and exhaust lobes. A cam of this type can be any combination of asymmetrical or symmetrical of profiles.

Didn't realize this was a thing. I'll have to check mine in a little bit.

So when I look at my cam, will all the lobes have that little ramp or will it be half with the ramp and half normal?

The question is would you be able to see it with your eyes as the rocker arm and valve sees it.
Looking at your cam card the obvious…? It’s a dual pattern. The exhaust’s lift and duration is different than the intake’s.
I’m not sure you can tell by eye whether it has the more desirable (to some) asymmetrical opening and closing lobe profiles, or symmetrical lobe profiles. It would be a challenge to measure accurately enough and graph the actual lifts vs degrees of the opening and closing ramps to make that determination. Especially if the two ramp profiles weren’t radically different.
It was once believed for maximum efforts the opening ramp should open the valve as quick as possible within the springs ability to control it from being launched off of the desired lope profile. Then have a closing ramp that literally lets the valve free fall or close as fast as the spring could close it but at the very last moment, gently catch it and set it near the base circle ever so gently. All Theoretically of course. You’ve already bought your cam so this really don’t matter right now. It should help you understand why PeWe is worrying about averaging his observed errors of his installed cams opening and closing points.

It still amazes me to see how such a simple motor can have such complexities when you really get into it all. I mean I've always known what a camshaft is, just never realized how intricate they could be, most especially when it comes to snagging every bit of power you can from an engines components, like the cam.

[PeWe]

You'll get it after some training.
Understand the cam profile details as served here, a bonus
Get similar numbers as the cam card is the goal.
Or IN differ from card as EX does.

[Ellz10]

You'll get it after some training.
Understand the cam profile details as served here, a bonus
Get similar numbers as the cam card is the goal.
Or IN differ from card as EX does.

Is there a general number or a range, as in closeness to the cam card numbers, that I would be okay in?