Installing Custom Roller Cam per FABO reccomendations

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Cam installed and what a dog! You would of thought that with 20 degrees less overlap and ~4 degrees less duration I would of seen an improvement..... totally devastated … But after further inspection...…

2018-06-17 14.21.40.jpg


Before install, PSI was ~130...… now ~120...… WTF?

Looks like I aligned the marks just a bit off.... Wanted 4 degrees advance but will try dot to dot.....should of bought a Tesla... :)
 
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2018-06-17 16.21.13.jpg
Degree Cam.... no....should I have done that.... yes.... but I work with what I have.... cam installed dot to dot and will post PSI and "performance".....Amazing what a few degrees of cam phasing can do to the all around engine attitude.....
 
AMEN to that cam may not be ground on the marks one on this forum 8 degrees off this week (it was an
What's the triangle? retarded?
any oil on that chain?
are you going to run a whatever it is on the slack side?
 
Triangle is 4 degrees advanced..... this is a custom grind.... so your comment has validity.....
 
Not just the cam can be ground 'off'. Timing gearsets are all over the place just as well.
I mixed and matched 3 timing sets once to get a cam to degree where it needed to be.

Get/Print a degree wheel and do it right.
 
Hmmm. that is indeed a dissapopintment. Yes... 4 degrees actually advanced and less ADVERTISED duration and overlap should have INCREASED the cranking pressure. But we don't know the actually advertised duration on the new cam to know if the intake valve will close earlier since that number is not in your original post. All we know is the the LSA is 2 degrees larger and the intake will close later unless the advertised duration is considerably shorter. With a roller, you SHOULD be able to get a bit steeper ramps but we just don't know right now.

And I hate to admit this at this point, but I had not actually looked hard at your prior numbers. Now I see that the original cam had an overlap of 48 degrees, not 59 degrees. So it would like to see the advertised duration numbers on the new cam to know. (But if this is, or is like, a Hughes cam they don't openly publish the advertised duration numbers.)

If you didn't get that number, then once the cam is degreed, you can also measure the advertised duration degree numbers; IIRC, Comp measures advertised duration at .006" lift at the lifter.

BTW, if you like, here is a printable degree wheel. Print it and glue to very thick, heavy cardboard or poster board. Make sure the center hole is centered precisely to maintain accuracy.
The Machinery Cleanery Universal Timing Disc, Degree Wheel, Downloadable - Goniometro per Messa in Fase dei Motori a 4 Tempi -
 
nm9stheham said:
Hmmm. that is indeed a dissapopintment. Yes... 4 degrees actually advanced and less ADVERTISED duration and overlap should have INCREASED the cranking pressure. But we don't know the actually advertised duration on the new cam to know if the intake valve will close earlier since that number is not in your original post. All we know is the the LSA is 2 degrees larger and the intake will close later unless the advertised duration is considerably shorter. With a roller, you SHOULD be able to get a bit steeper ramps but we just don't know right now.

And I hate to admit this at this point, but I had not actually looked hard at your prior numbers. Now I see that the original cam had an overlap of 48 degrees, not 59 degrees. So it would like to see the advertised duration numbers on the new cam to know. (But if this is, or is like, a Hughes cam they don't openly publish the advertised duration numbers.)

If you didn't get that number, then once the cam is degreed, you can also measure the advertised duration degree numbers; IIRC, Comp measures advertised duration at .006" lift at the lifter.

BTW, if you like, here is a printable degree wheel. Print it and glue to very thick, heavy cardboard or poster board. Make sure the center hole is centered precisely to maintain accuracy.
The Machinery Cleanery Universal Timing Disc, Degree Wheel, Downloadable - Goniometro per Messa in Fase dei Motori a 4 Tempi -
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nm9stheham.... I thank you for your research and your advice.... but what I thank you the most for is the time you took to get me the hyper-link for a degree wheel...ppl like you who are willing to help ppl like me to succeed are a precious asset... it speaks volumes of your character....
 
You're very welcomed! Hey, this is motors and cars and I am truly very happy to be able to muck around with them... that is what makes it easy to try to help.

Now if we could just come up with a cheap way to consistently find approximately .050" lifter lift without a dial indicator, then the other cost in degreeing a cam could be bypassed. I bet someone here has a clever way it doesn't have to be EXACTLY .050" lift for most standard cams.
 
You don't think that this is why I have poor performance?
2018-06-26 19.34.03.jpg
 
Did you use roller cam pushrods of flat tappet pushrods? How many bent?
 
I'd put a 350 hp 327 cam in the thing and call it good...........
 
yellow rose said:
What math test? It's borderline idiotic to tell everyone if you don't run a lobe designed for a .904 lifter you are wasting your time.

I'd bet my bottom dollar if I called Mike Jones right now to order a cam for my street/strip car he'd spec lobes from an .842 lifter. I know, because he did.

So would you argue with Mike about using the wrong lobe and tell him his math is off?
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yellow rose said:
I agree. My problem is actually getting lobes that are designed for a .904 lifter. And I'm not sure for most of what most guys are doing, that they'd see a benefit with a .904 lobe.
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Exactly! Thank you.

I spent a lot of time in the catalogs and on the phone with some grinders, not phone tech guys, as well as swapping cams around.

In the street and most track, you will NEVER know what lobe is on the cam. While the dyno will show the differences between the various cam lobes, when less than a maximum effort is applied, not only will you never know but the extra effort just puts extra wear on the engine parts.

High performance = high stress = high maintenance
 
I can assure you they or where the same length. Pic at an angle….
 
Not sure what happened to your pushrods. Piston to valve contact?
You need to start over. Are you running adjustable rockers?
Need to get a adjustable push rod to determine correct push rod length. Degree the cam.

Get engine straightened out then install higher stall convertor and 4.10 or 4.56 gears.

Then go out and buy a 360...lol
 
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bschubarg said:
Cam installed and what a dog! You would of thought that with 20 degrees less overlap and ~4 degrees less duration I would of seen an improvement..... totally devastated … But after further inspection...…

View attachment 1715188475

Before install, PSI was ~130...… now ~120...… WTF?

Looks like I aligned the marks just a bit off.... Wanted 4 degrees advance but will try dot to dot.....should of bought a Tesla... :)
Click to expand...

Might be the picture but that looks to me like the cam gear is retarded if it's supposed to line up with that 4* advanced mark.
 
moper said:
Might be the picture but that looks to me like the cam gear is retarded if it's supposed to line up with that 4* advanced mark.
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Are you looking at the pix in post #26? If you mean that the crank sprocket's triangular mark is a bit off to the left, would that not mean advanced?

BTW, for the OP, I always use a straight edge carefully laid across the cam bolt and going to the top, center of the crank snout, to judge dot alignment.
 
Camshafts for Chrysler
Lunati, Howard/ Hughes have a good assortment in their catalogues ( depending on carb and exhaust and compression a shelf cam may or may not be found)
Crane, Engle, Bullet also have a good selection special order with Crower you really have to ask
Comp has the XE275, 285, 296 XL series
Jones only has his Motorhome special in Hyd great for low compression builds - outstanding FT and HR series though
not to rumble but it's easy to give up 25 or more ft lbs at take off speed- look at what they do with the broad torque curve Engine Masters builds
 
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