Another cam degree question!!

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green72

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I apologize for more confusion on this subject. I am putting together a slant and want to degree the cam. I know some will say it’s not necessary but I want to understand it. I have followed Dutras book. I’m not exactly sure what his instructions tell me? Here’s what I have if someone can explain. Be gentle haha.

C90F68BC-13EA-4235-BC1E-1CAAD9B83A06.jpeg


C05EEE66-08C9-48CA-B6AA-C0A91C921CF6.jpeg
 
Ok so watched the video, made me realize how much I’m overthinking!
Centerline is perfect as it’s installed.
Is that it?
What is Dutras method accomplishing (same thing just different method)?
 
Interesting cam specs, reverse pattern cam [ less exh duration ].
 
I think it is going to depend on what the goal is. If it is to pump up low/mid range torque by cutting back on overlap, then it could work well. If more peak hp is the goal, probably not a good choice.
 
Peak horsepower is not the goal here, more low/mid range torque is. That said this is the cam that Oregon cams recommend. I also did a lot of reading on here and Slant six.org. I got the impression that this is a good choice. Not to far in the process to change if there are better choices out there.
 
I also got my cam done by Oregon cams. I picked it myself based off of ancient posts both here and the /6 site, I went with the #819. I beat myself up about it especially right after I got it into the engine, but it seems there are a lot of cams that are pretty close to each other and will work pretty much the same. I have my engine back together and have run it in the garage a couple of hours so far but haven't yet had it on the road.
You aren't the only one who has trouble decreeing a cam. I'm right with ya. I've assembled plenty of engines over the years usually just doing the "dot to dot and forget it" deal. I've only ever degrees in a couple of them and it's a struggle each time. Because I did it once and there were several years between attempts at the degreeing process.
Once I get into it I figure it out once again,
I've degreed in a couple successfully along with this forum holding my hand each time, but in between I've done a couple, gotten confused said "screw it", done the dot to dot thing, hid the timing set behind the cover and went on with life.
 
volaredon said:
I also got my cam done by Oregon cams. I picked it myself based off of ancient posts both here and the /6 site, I went with the #819. I beat myself up about it especially right after I got it into the engine, but it seems there are a lot of cams that are pretty close to each other and will work pretty much the same. I have my engine back together and have run it in the garage a couple of hours so far but haven't yet had it on the road.
You aren't the only one who has trouble decreeing a cam. I'm right with ya. I've assembled plenty of engines over the years usually just doing the "dot to dot and forget it" deal. I've only ever degrees in a couple of them and it's a struggle each time. Because I did it once and there were several years between attempts at the degreeing process.
Once I get into it I figure it out once again,
I've degreed in a couple successfully along with this forum holding my hand each time, but in between I've done a couple, gotten confused said "screw it", done the dot to dot thing, hid the timing set behind the cover and went on with life.
Click to expand...
I could have written this entire post.
what are your second thoughts on the 819?
 
green72 said:
Didn’t work? Can you elaborate?
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The reverse grinds didn't make any more power or torque. The exhaust side of the slant 6 head is poor at best. It needs all the help it can get. Cutting exhaust lift and duration wasn't the way to go. The best thing to do is to have the head ported and install larger valves. It's much more of a head problem than a cam problem.
 
....and I'm not knockin Dutra here. The guy's a genius. You gotta try something to see if it'll work and he's tried more than anyone has with the slant 6. Tore up a bunch of stuff. LOL But that's how you do it. You think outside the box and he's good at it.
 
green72 said:
I could have written this entire post.
what are your second thoughts on the 819?
Click to expand...
I haven't driven it yet, so can't tell for sure yet, more of a coming on here and seeing "I went with THIS cam". And someone else says they went with "THAT" cam, all looking for similar results had me wondering if I could have done better than what I did. Won't know til I'm sure they're done with salt on the roads and I get it licensed......
 
volaredon said:
I haven't driven it yet, so can't tell for sure yet, more of a coming on here and seeing "I went with THIS cam". And someone else says they went with "THAT" cam, all looking for similar results had me wondering if I could have done better than what I did. Won't know til I'm sure they're done with salt on the roads and I get it licensed......
Click to expand...
oh my we are living a parallel life!!! These guys are amazing but get in my head sometimes LOL
 
The last time I degreed my slant engine I did it a few times.
I have my method, for whatever reason and plot the events every 10 degrees in excel.
Now during this latest work I found that my timing set could not be installed "dot to dot"
It's a double roller set I purchased from the Cox Brothers a few years ago.
I think it might be from down under, no markings.
But painting dots on the center of the cam bolt and the crank bolt,
and highlighting the dots on the big and little gear,
it would NOT line up.
So it has to go in either one tooth retarded or one tooth advanced.
It is close, bot not dot to dot.
No big deal since I have offset bushings and I get pretty close to what I need or wanted.
I really guess on a street engine the misalignment forward or aft would never be felt.
Anyway just more wood on the fire.
 
I have had that same situation on occasion. I had to install the timing set one tooth off and then use a bushing to get the timeing correct. At dot to dot, it was too far off to correct the timing with a bushing.
 
Ok so let’s revisit one of my questions at the top of this thread.
What am I supposed to do with the information that I got while using the method from Dutras book.
Picture above shows results but I have no idea what to do with it
 
My advice to you is get it as close as you can.
It's a street car, you just want good performance.
Without a Dyno you have no way to compare your baseline to the resulting changes.
A couple of degrees are almost impossible to detect.
Really once the Intake Centerline is where it needs to be, you can't change any other other events.
That is built into the cam.
 
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I have determined the intake center line is on the money with a different method.
Still unclear what I was accomplishing with Dutras method.
I don’t need to know, I just want to understand
 
green72 said:
I have determined the intake center line is on the money with a different method.
Still unclear what I was accomplishing with Dutras method.
I don’t need to know, I just want to understand
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Then go on Comp Cam's web site and read the intake center line method and do it. Several times. Do it as many times as it takes until the light bulb comes on. I've done hundreds, but as simple as my mind is, I still have to have the instructions in front of me and go slowly step by step. It's not difficult to do, but it's important enough that you don't want to make a mistake. What timing set do you have? I use the JP (Rollmaster) sets with NINE keyways in the crank sprocket. If you cannot get it DEAD ON with that, plus cam sprocket bushings, something is WRONG.
 
Hyper_pak said:
I really guess on a street engine the misalignment forward or aft would never be felt.
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I don't agree. Even on a stock engine, the difference between correct cam timing and cam timing that's a little off, more or less sort of in the ballpark, I donno, whatever can be felt in just about every aspect of driveability and performance, and seen every time you calculate your gas mileage.
 
Everyone is entitled to an opinion.
Like on the chain set I have there is no way to set dot to dot.
So, you set it where you can.
Or, you degree it in.
 
Crane Cams claims that if the cam is to be adv or ret, it should be a minimum of 4* for the butt-meter to feel the difference.
 
slantsixdan said:
I don't agree. Even on a stock engine, the difference between correct cam timing and cam timing that's a little off, more or less sort of in the ballpark, I donno, whatever can be felt in just about every aspect of driveability and performance, and seen every time you calculate your gas mileage.
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I tend to agree. While we all know the slant 6 is a great engine, they need "all the little parts" to the puzzle to run really strong. Every little detail helps.
 
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