Degreeing a Cam, or not.....

Would you run it or take it apart and correct it?

  • Total voters
    34
-
K

Kent mosby

FABO Gold Member
FABO Gold Member
Joined
Aug 24, 2018
Messages
1,232
Reaction score
1,284
Location
Idaho
Well, I am an idiot engine builder. I built my 512 RB from scratch. Fresh block, completely new rotating assembly, new cam, lifter,,,,,everything. But, when I assembled it I measured everything and it all went together smoothly. What I did not do was degree the cam. I now know that was a big no no. How could I be so dumb? As I look back on the results of the build, I see a big motor that sounds great but underperforms on the racetrack. I have gone 12.3 seconds in the quarter mile but on paper I should be much better. I know that there are other factors but I look back on the lack of degreeing the cam as a possible source of frustration. The cam was built by Ken of Oregon cams. The specs are.

244/252 @ .050”, 282/290 adv, .516”/.537” lift(1.5:1 rocker), 112 sep, .016”/.018” lash

This is a very good street/strip grind that should make power from 2200/6400 or so. Will need a 3000+ converter and will work well with your compression ratio. Normally I would put this on a 110 lobe separation but with the nitrous and fuel injection I think 112 to 114 would work better.

Is there any way to correct this without pulling the entire front of the motor off?? This is a. what would you do if you bought the car and knew this was the situation?? The racetrack in Spokane will open sometime in the future and I hope to race it again there. I may also consider a new cam without the nitrous accommodation. Something more aggressive.

What would you do? I know that I was stupid. Go ahead and remind me, or not.
 
No way to correct it without taking it apart. If you leave it together it might be fine or you might be leaving some performance behind. Millions of cams have been installed without degreeing. Take your chances.
 
Until you verify exactly where the cam is installed, it’s the same as “the cat in the box”.
It might be dead on, it might be way off.
 
I wanna say you can check it without taking everything apart by finding TDC and putting an indicator on the valves. I could be wrong but seems to me I've read about it somewhere.
 
I read somewhere that if you use the timing set that is the same as the manufacturer of the cam, it will be close OOTB.
This may be an old wives tale, but is there any truth to this? (experts)
To the O.P., the only sure way to tell where the cam is phased is to pull the front end off and the valve covers to verify where you are at.
At the same time, maybe get the other cam you were thinking of and then degree that one.
Open it up once, and then you'll know for peace of mind if nothing else..........
 
Think of it this way, if you are racing it, pull the engine and set it up. a day or weekend job at most and a set of gaskets. On the street I'd say leave it dot to dot.
 
Kent mosby said:
Well, I am an idiot engine builder. I built my 512 RB from scratch. Fresh block, completely new rotating assembly, new cam, lifter,,,,,everything. But, when I assembled it I measured everything and it all went together smoothly. What I did not do was degree the cam. I now know that was a big no no. How could I be so dumb? As I look back on the results of the build, I see a big motor that sounds great but underperforms on the racetrack. I have gone 12.3 seconds in the quarter mile but on paper I should be much better. I know that there are other factors but I look back on the lack of degreeing the cam as a possible source of frustration. The cam was built by Ken of Oregon cams. The specs are.

244/252 @ .050”, 282/290 adv, .516”/.537” lift(1.5:1 rocker), 112 sep, .016”/.018” lash

This is a very good street/strip grind that should make power from 2200/6400 or so. Will need a 3000+ converter and will work well with your compression ratio. Normally I would put this on a 110 lobe separation but with the nitrous and fuel injection I think 112 to 114 would work better.

Is there any way to correct this without pulling the entire front of the motor off?? This is a. what would you do if you bought the car and knew this was the situation?? The racetrack in Spokane will open sometime in the future and I hope to race it again there. I may also consider a new cam without the nitrous accommodation. Something more aggressive.

What would you do? I know that I was stupid. Go ahead and remind me, or not.
Click to expand...
I ran a much more aggressive cam in my 512.
What heads do you have and what has been done to them?
You can have the best cam in the world and if the heads wont flow decent were just pissing away money.
Either way the cam should be degreed in.
 
As meticulous as you are on your car build Kent, I would doubt you are way off on your cam timing events.

I would be more inclined to point the finger to the aftermarket fuel injection system as to not delivering the performance you desire. You have an on board computer to go with that, Oxygen Sensors, who knows if your fuel system coordinates with your ignition system through the computer. Lots of variables getting all those systems working together well.

Process of Elimination
 
3858750D-52DB-4C09-AA38-F67F9764AE7A.png
 
512Stroker said:
I ran a much more aggressive cam in my 512.
What heads do you have and what has been done to them?
You can have the best cam in the world and if the heads wont flow decent were just pissing away money.
Either way the cam should be degreed in.
Click to expand...
I have trick flow, tf240, heads that are cnc machined. Should flow well.
 
George Jets said:
As meticulous as you are on your car build Kent, I would doubt you are way off on your cam timing events.

I would be more inclined to point the finger to the aftermarket fuel injection system as to not delivering the performance you desire. You have an on board computer to go with that, Oxygen Sensors, who knows if your fuel system coordinates with your ignition system through the computer. Lots of variables getting all those systems working together well.

Process of Elimination
Click to expand...

The sniper efi talks to the ignition and distributor to control timing and air/fuel ratio. It was professionally tuned (remotely) and has learning capability.
 
There is probably some truth to this, but on the other hand, there are times when you might deliberately want to install the cam with different amounts of advance (using an offset key). The only way to do this is by degreeing. Some people seem to just want the lopey idle and don't care about performance, for example...

I had the heads off and was installing a new timing set, so I thought I would check my cam, and as it turned out it was right on spec. But I didn't know that until I degreed it.

Dartnut said:
I read somewhere that if you use the timing set that is the same as the manufacturer of the cam, it will be close OOTB. This may be an old wives tale, but is there any truth to this? (experts)
....
Click to expand...
 
Kent mosby said:
The sniper efi talks to the ignition and distributor to control timing and air/fuel ratio. It was professionally tuned (remotely) and has learning capability.
Click to expand...
How much cfm will the EFI flow?
 
Your cam seems REALLY small for a 500 cube motor, and 800cfm is WOEFULLY inadequate in my opinion. I ran a dual 4 barrel fitech unit on a 410 smallblock, that was probably 1200 cfm, and the engine was super crisp right off idle, even with all 8 barrels open at the same time
 
The only known answer in your question OP is the "unknown." It needs to be done plain and simple....... Only one direction on this one....

JW
 
That’s a tiny cam for a 512 engine. As stated too small of fi system also. Degree the cam at least. I doubt that ur engine even pulls to 5500. It’s a torque monster for sure. A 1000 4150 style carb will pick it up like u won’t believe. My 470 gained 2.5 tenths going from a 750 to a 1000. Kim
 
Kent mosby said:
Well, I am an idiot engine builder. I built my 512 RB from scratch. Fresh block, completely new rotating assembly, new cam, lifter,,,,,everything. But, when I assembled it I measured everything and it all went together smoothly. What I did not do was degree the cam. I now know that was a big no no. How could I be so dumb? As I look back on the results of the build, I see a big motor that sounds great but underperforms on the racetrack. I have gone 12.3 seconds in the quarter mile but on paper I should be much better. I know that there are other factors but I look back on the lack of degreeing the cam as a possible source of frustration. The cam was built by Ken of Oregon cams. The specs are.

244/252 @ .050”, 282/290 adv, .516”/.537” lift(1.5:1 rocker), 112 sep, .016”/.018” lash

This is a very good street/strip grind that should make power from 2200/6400 or so. Will need a 3000+ converter and will work well with your compression ratio. Normally I would put this on a 110 lobe separation but with the nitrous and fuel injection I think 112 to 114 would work better.

Is there any way to correct this without pulling the entire front of the motor off?? This is a. what would you do if you bought the car and knew this was the situation?? The racetrack in Spokane will open sometime in the future and I hope to race it again there. I may also consider a new cam without the nitrous accommodation. Something more aggressive.

What would you do? I know that I was stupid. Go ahead and remind me, or not.
Click to expand...

what was the trap MPH on the 12.3 runs? what about the 60ft times?
is your car setup to be a drag car or is it just a street car?
 
If it's gutless, you'll know why.

I've had many be right on.

Had a .528 mp cam and JP performance billet timing set be set 8 degrees retarded to be 2 advanced...i later set it to 5 retard for 5 adv where it ran real good.
 
Kent mosby said:
Well, I am an idiot engine builder. I built my 512 RB from scratch. Fresh block, completely new rotating assembly, new cam, lifter,,,,,everything. But, when I assembled it I measured everything and it all went together smoothly. What I did not do was degree the cam. I now know that was a big no no. How could I be so dumb? As I look back on the results of the build, I see a big motor that sounds great but underperforms on the racetrack. I have gone 12.3 seconds in the quarter mile but on paper I should be much better. I know that there are other factors but I look back on the lack of degreeing the cam as a possible source of frustration. The cam was built by Ken of Oregon cams. The specs are.

244/252 @ .050”, 282/290 adv, .516”/.537” lift(1.5:1 rocker), 112 sep, .016”/.018” lash

This is a very good street/strip grind that should make power from 2200/6400 or so. Will need a 3000+ converter and will work well with your compression ratio. Normally I would put this on a 110 lobe separation but with the nitrous and fuel injection I think 112 to 114 would work better.

Is there any way to correct this without pulling the entire front of the motor off?? This is a. what would you do if you bought the car and knew this was the situation?? The racetrack in Spokane will open sometime in the future and I hope to race it again there. I may also consider a new cam without the nitrous accommodation. Something more aggressive.

What would you do? I know that I was stupid. Go ahead and remind me, or not.
Click to expand...
If you can yank teeth and rebuild them I'm sure you could learn how to degree a cam.
at least I hope, otherwise you won't be working on my teeth. lol
myself I'd probably retard it. but that's me
 
PRH said:
Until you verify exactly where the cam is installed, it’s the same as “the cat in the box”.
It might be dead on, it might be way off.
Click to expand...
what's dead on.
 
You must log in or register to reply here.
-

Back
Top