I keep reading people say to "degree in the cam".
Thats fine. What difference does it make though? In all of the cam installs in magazine articles, only about half of them degree the cam. Of the ones that get degreed, I don't remember reading about any corrections that were made. Small blocks use the single bolt. Most big block cams are also single bolt. What is the procedure to make corrections? Oval out the dowel hole and fit a crescent in the void? Weld up the open section?
I'm getting ready to put a Lunati Solid flat tappet in the 440/493 in my Charger. I have never degreed a cam before. When this engine was first built in 2004, a friend brought over his stuff and helped me.
A few questions to satisfy my curiosity:
*If the timing set is installed with the Cam sprocket dot at 6:00 and the crank gear at 12:00 and the cam timing isn't spot on, where is the error? Is it in the cam, the timing set or both?
*How often is it that an error is found and needs to be corrected? In other words, are some cam manufacturers products more prone to be inacurrate?
* Out of 10 cam installs that get degreed, how many are close enough to skip any additional work?
I really want to do the right thing here, but I have seen so many cases where this procedure was skipped or not needed.

yeah you pretty much got it, your not realy doing anything but checking to make sure your crank, cam and timing set are in spec to get your cams specified installed centerline right and to know how much to compensate if it is off or you want to advance/retard cam timing. most new timing sets have several keyway slots on the crank gear to get you atleast close if you do encounter any manufacturing errors. for the most part it's a peace of mind thing especially with most of this stuff comming from china.

I always thought degreeing a cam was horseshyt until I got 3 timing sets from Mopar Performance that had the dot on the cam gear 15° retarded.

I helped degree mine.

I had a rollmaster with different degreed keyways.

Troy used his degree wheel and did the one in my motor.

We did notice the MP timing chain tensioner changed the degree measurement by 1 degree. We used the keyway slot that gave the degree measurment recommended.

TDC



W/O timing chain tensioner



W/ timing chain tensioner



bend in chain from tension against just a little chain slop. "Felt" tight w/o tensioner.



Basic setup

It's one of those things that after tons of hours and dollars I degree the cam in to not have a nagging question in the back of my mind. I have a cheap magnetic base for a decent dial indicator and a small degree wheel I printed out and glued to a cheerios box to stiffen it up- NOT a spendy pro setup. I do know that my last cam install was four degrees advanced dot to dot which fell right into a range I am comfortable with.

So now I can concentrate my engine building anxieties on other nagging questions- is the quench tight enough? Etc haha

When you have the dots lined up it is firing #6. DAMHIK.

just degree the cam,its worth it,since nothing else is machined right from the factory why would you trust the cam to be machined right? i have seen cams all over the map..

"dot to dot". Period.
And the earth has not tilted off its axis....
It's a STREET motor for gawdsakes!!!!!!!!!!

You'll never know whether it needs to be done until you do it.

It might be say a 1/2 degree retarded which is OK in most cases but isn't it nice knowing that? Usually you'll never get it exact with stock timing pieces but you need to know whether the cam is advanced or retard when you install it. Then I can tune accordingly. There again it matters on say a truck engine that needs torque.

I learned to degree in cams when I was about 20 years old. I could never just line up the dot's. I could not sleep at night not knowing where the cam was installed at. Yes I have found them to be off and have done whatever it takes to correct the timing. Sometimes you have to get a different timing gear.

At the drag strip I have found 8 MPH at the finish line by moving the cam around in a blown hemi.

BTW the small moroso wheel is too small for accurate cam timing IMO.

I have done countless motors, GM, Ford,Mopar and International gas truck engines, like in more than one truck engine and it's like a performance engine. It needs every pony it can put out. The cam has to be right in a truck engine otherwise you will know it under heavy loads..
See how worn my crank adapter is, it's been used a lot.

I got this small wheel in a ebay deal, after using the big wheel the small wheel is very hard to use. Bigger the wheel the more space between degrees making it easier/more accurate to use.


Move your cam around and then go drive the car(test). It's a very eye opening experience.

I just remembered that I built 4 bike motors for drag racing. GSXR big block/bore motors for myself and a customer back in the late 80s.



Got my first sponsor on this bike. A very trick bike with a air pressurized rear swingarm for the air shifted full auto trans. 9.20s at 141mph

Do you check your ring end gaps? Bearing clearances? Etc.

I have had a few cams that were within a degree or so. But most have been off more than 2 degrees. I don't know at what point it really starts to matter, but I don't have to worry about it. Just another variable eliminated.

With one manufacturer machining the slot in the crank, another the cam, another the gears and probably another making the chain, the chance for tolerance stack up is very real.

My engines are not perfect, but once in a while a cam can end up far enough off to matter. Just like ring end gaps and bearing clearances. I want to KNOW those things are within allowances BEFORE I button it up. Not chasing gremlins down after it's in the car and running.

A half an hour or so to degree in a cam is much better than tearing a running engine back down to see if it is a problem if the engine doesn't run right.

More like cheap insurance than anything for me.

From reading your post you know you want to . To answer your Q the error (if present) is generally in the gears not the cam & with the junk being sold nowadays I would absolutely check everything. & once you do it it ain't that bad. You're pretty much just finding the point on the degree wheel where the #1 cyls' intake lobe (intake centerline method) is at it highest point (just like finding piston exact TDC) & seeing how far (degrees on the wheel) that point is from the piston being at TDC & the sprockets change that. The lobe peak is the cam baseline & the piston TDC is the crank baseline & you're seeing how far one is located/turned/shifted in relation to the other one (advanced or retarded from the baseline provided by the cam mfr). If it's 104 deg & you shift the cam forward clockwise which is advancing it's position (with the crank not moved) so the peak of the lobe is now only 102 degrees away from piston TDC (it's closer) then you have advanced the cam 2 (crank) deg. Cams have some advance built in which slightly complicates grasping it & first you always want to check/confirm that the dampener slit when on zero on the tab is at exact piston TDC.

Good point RR.
Most important to begin with, is finding TDC. Can't do that properly without a degree wheel and a piston stop.

We degree all our cams.

I always degree my cams. The dot to dots have always been right but it just takes one time to really wreck your day.

Sheldon

Would you use a framing square that was 85* instead of 90?

I degreed a 509 cam last year that straight up dot to dot came out 7 degree retarded from the 106 it should have been straight up. 113 moved it to the 4 advance slot and it came in at 106.5 4 speed so I left it gear set had a slot so no drilling that for an offset bushing!
It would have been a giant dog at 113.

That was a 3 keyway mancini timing set guy had another brand new timing set was exactly the same matching them to a 3 keyway gear I had around the keyways were off a bit. Look Chineese to me! :-)

Often find them 2 to 4 deg off and that is huge. once went in and did a 509 found it at 108.25 was a dog to 3500 moved it to the 4 advance keyway and it came in at 103.75 and wow what a difference guy told me he was going to kill me if he had to pull the tranny and change the 3000 stall after going to the work of putting the motor and tranny back in. I knew he would be happy and he sure was car went from one that would hardly spin the tires from a dead stop to a sideways Sally!

I have heard of them being so far off the bent valves.

anyway the stacking affect of the cam keyway or dowel hole. the placement of the top gear dowel hole or keyway the placement of the bottom gear keyway and the keyway in the crank can be a little to a lot. Ever wonder why two identical motor builds one is just flat and other has great pop it's usually that one last thing cam fazing!
When people don't do it it's a shot in the dark.

So your saying you would rather have a pig than check??? I'd rather know that is where I want it before motor is buttoned up!!

The whole "dot to dot" thing has nagged at me since my first timing chain replacement in 1984. I used to always install timing sets dot to dot. Sometimes I was 180 out, sometimes it fired right up. I started off with Chevy engines, so maybe the quality control of the parts suppliers was all over the map?
Several years ago I started installing the gears with BOTH dots at 12:00 and haven't had any troubles since. I wasn't accurate in the opening post when I wrote dot to dot.
When I built this engine in 2004, I had a friend degree the '509 cam. With it set at ZERO, it came up at 1.5 degrees retarded. I can't recall what the timing card called for. It is the 108 centerline version of the '509 cam. When I switched to the 4 degree keyway, it came in at an accurate 4 degrees advanced. We left it at the advanced number until I switched to a Comp cam a few years later.
The timing set I have for the cam installation is new, an Edelbrock 7804 with 3 keyways: 4 degree RT, ZERO and 4 degree ADV.
The Lunati cam I have is the 316/326 solid flat tappet. I'm using EDM lifters too. THOSE look strange compared to other lifters. The center groove is a wide band, almost makes the lifter look like an hourglass!
Yeah, this is a street car, but with 10.7 compression and a cam this wild, I would feel like a total idiot if I skipped the degree work and fragged parts. I did file the rings to size. I plastiguaged the bearing clearances. Everything was torqued to spec. I should continue the practice of "blueprinting" to the cam install.

I just haven't read about many mistakes found during the degree process, nor have I read how to correct them. Thanks, Greg

509 108 LSA calls for 106 but they really like 104 to 102.

Bigger cams usually respond well to a couple extra degrees of cam advance.