#1  
Old 05-09-2021, 08:21 PM
jeff chmura jeff chmura is offline
Senior Chief
 
Join Date: Aug 2011
Location: Jackson,New Jersey
Posts: 428
Default Calculating intake lobe centerline

Hi all,
I want to check the degree of my cam.
I'm having issues trying to figure it out.
Can someone explain it to me.
Cam card pictured...
Thanks, Jeff
Attached Thumbnails
Click image for larger version

Name:	KIMG0005.jpg
Views:	307
Size:	51.8 KB
ID:	566265   Click image for larger version

Name:	KIMG0004.jpg
Views:	232
Size:	52.5 KB
ID:	566266  

  #2  
Old 05-09-2021, 08:57 PM
Scott65's Avatar
Scott65 Scott65 is offline
Ultimate Warrior
 
Join Date: Jan 2002
Location: Houston, Texas
Posts: 1,991
Default

Looks like the numbers in the "max lift" column are the centerlines of intake and exhaust. Verified by cam calculator at Wallace Racing site.
Check using intake centerline method, with 113. I'll defer to others whether 113 is the best place to install it as opposed to 109, or 111, (4, or 2 degrees advanced)

__________________
'65 Tempest 467 3650# 11.30@120.31
  #3  
Old 05-09-2021, 09:07 PM
jeff chmura jeff chmura is offline
Senior Chief
 
Join Date: Aug 2011
Location: Jackson,New Jersey
Posts: 428
Default

Thanks Scott,
That's where I'm at also....just a bit confused
The card isn't saying if it's ground with advanced or retard.
I installed it straight up,now I want to check if I should advance or retard and how much

  #4  
Old 05-09-2021, 09:34 PM
Scott65's Avatar
Scott65 Scott65 is offline
Ultimate Warrior
 
Join Date: Jan 2002
Location: Houston, Texas
Posts: 1,991
Default

I would say it's ground with a 113, to be installed there. Hopefully you get some advise on whether to move it. I couldn't say, I've never used it.
ETA: If you can do a cranking compression check straight up and 4 advanced, that can offer clues.

__________________
'65 Tempest 467 3650# 11.30@120.31

Last edited by Scott65; 05-09-2021 at 09:35 PM. Reason: Addition
  #5  
Old 05-09-2021, 09:45 PM
AG's Avatar
AG AG is offline
Ultimate Warrior
 
Join Date: Feb 2000
Location: NH
Posts: 3,240
Default

You need to call the cam manufacturer and ask. The RAIV cam used a 113.5 LSA (I think) so it looks like that that one is advanced 0.5 degrees for installation.

__________________
1967 Firechicken, 499", Edl heads, 262/266@0.050" duration and 0.627"/0.643 lift SR cam, 3.90 gear, 28" tire, 3550#. 10.01@134.3 mph with a 1.45 60'. Still WAY under the rollbar rule.
  #6  
Old 05-09-2021, 10:32 PM
jeff chmura jeff chmura is offline
Senior Chief
 
Join Date: Aug 2011
Location: Jackson,New Jersey
Posts: 428
Default

That's the way I'm reading this card also.
So now I'm wondering if I should try advancing / retarding
the cam, 2-4 degrees,checking piston to valve clearance and checking drivability....
Never had one that didn't say ILC...

  #7  
Old 05-09-2021, 10:32 PM
Jay S's Avatar
Jay S Jay S is offline
Ultimate Warrior
 
Join Date: May 2018
Location: Nebraska City, Nebraska
Posts: 1,671
Default

That appears to be an old Crane regrind of the 041. I don’t know if Crane even has customer support anymore, I think for that might be handled by compcams now.

Just like the others said, the ICL is position to be 113. Depends on the engine and car set up it is going in for where to install it. It can be a little soft on the bottom end if it is install as it is (113). Most install it on 109-111.

  #8  
Old 05-09-2021, 10:37 PM
jeff chmura jeff chmura is offline
Senior Chief
 
Join Date: Aug 2011
Location: Jackson,New Jersey
Posts: 428
Default

Jay,
I'd say it's soft....
It makes power above 2500 rpm as advertised,
But I want a bit more bottom end.
The car is a 4 speed 2.59 1st gear with 3.31's
It's a bit to get moving and has a hesitation under 1200 rpm, so I was thinking maybe advance 2-4degrees and see if it helps.

  #9  
Old 05-10-2021, 12:16 AM
Brian Baker's Avatar
Brian Baker Brian Baker is offline
Ultimate Warrior
 
Join Date: Feb 2000
Location: Glen Burnie, MD USA
Posts: 17,184
Default

"The card isn't saying if it's ground with advanced or retard"

THIS is where a lot of confusion lies when degreeing a cam. When you are physically degreeing in a cam, whatever they advertise as "4 degrees advanced ground in" or the like is moot. I believe cam manufacturers do this for those who are just going to install it "straight up, dot to dot" without actually putting a degree wheel on it. Once you put a degree wheel to it and verify where the intake centerline is, THAT is where it is, not 2 degrees retarded or 4 degrees advanced.

__________________
Just a blind squirrel looking for a nut.
  #10  
Old 05-10-2021, 12:27 AM
Brian Baker's Avatar
Brian Baker Brian Baker is offline
Ultimate Warrior
 
Join Date: Feb 2000
Location: Glen Burnie, MD USA
Posts: 17,184
Default

If you want to move the power curve lower in the operating rpm range, degree it in at 111 or 109 intake centerline for either 2 or 4 degrees advance respectively.

Quote:
Originally Posted by jeff chmura View Post
Jay,
I'd say it's soft....
It makes power above 2500 rpm as advertised,
But I want a bit more bottom end.
The car is a 4 speed 2.59 1st gear with 3.31's
It's a bit to get moving and has a hesitation under 1200 rpm, so I was thinking maybe advance 2-4degrees and see if it helps.

__________________
Just a blind squirrel looking for a nut.
  #11  
Old 05-10-2021, 12:38 AM
jeff chmura jeff chmura is offline
Senior Chief
 
Join Date: Aug 2011
Location: Jackson,New Jersey
Posts: 428
Default

Makes sense,. Thanks guy's

  #12  
Old 05-10-2021, 02:12 AM
lust4speed's Avatar
lust4speed lust4speed is offline
Ultimate Warrior
 
Join Date: Jul 2002
Location: Yucaipa, SoCal
Posts: 8,684
Default

LSA is 113.5 on this cam [(113+114)/2], but the intake centerline is 113. You have to ask yourself whether the cam company knows more about where they specify the intake centerline to be or if someone wants to gamble and pick another centerline out of thin air. More times than not advancing a cam 4° can loose horsepower across the curve. What you probably will end up with advancing the cam is moving the torque and horsepower peaks down around 200-250 RPM lower, but these peaks will probably have less power than the power generated at the cam company's specified centerline.

Now hitting the centerline is like horseshoes, and close is usually all you will get. Basically you might having to be satisfied being up to 2° advanced or 2° retarded even using the crank gear key slots or cam offset keys. In this case I would go for the slight advance since the chain will stretch some and slightly retard cam timing as you put on miles.

__________________
Mick Batson
1967 original owner Tyro Blue/black top 4-speed HO GTO with all the original parts stored safely away -- 1965 2+2 survivor AC auto -- 1965 Catalina Safari Wagon in progress.
  #13  
Old 05-10-2021, 09:26 AM
track73 track73 is offline
Ultimate Warrior
 
Join Date: Nov 2006
Location: Munster In
Posts: 1,504
Default

I set my 041 at 2 degrees BTDC at .050 lift and let it go. The engine runs great

__________________
1979 Trans Am WS-6 .030 455 zero decked
flat pistons
96 heads with SS valves
041 cam with Rhoads lifters 1.65 rockers
RPM rods
800 Cliffs Q Jet on Holley Street Dominator
ST-10 4 speed (3.42 first)
w 2.73 rear gear

__________________________________________________ _______________________________

469th TFS Korat Thailand 1968-69 F-4E Muzzle 2
  #14  
Old 05-10-2021, 09:48 AM
77 TRASHCAN's Avatar
77 TRASHCAN 77 TRASHCAN is offline
Ultimate Warrior
 
Join Date: Oct 2008
Location: 31May2013 Temporary home to the world's widest (that we know of) tornado. Lord, NO more Please...
Posts: 6,591
Default

In my years of reading here....109 or as close to it as possible seems like the preferred setting. Thinking Cliff, Jim Hand and many others preference...maybe...

__________________
1977 Black Trans Am 180 HP Auto, essentially base model T/A.
I'm the original owner, purchased May 7, 1977.

Shut it off
Shut it off
Buddy, I just shut your Prius down...
  #15  
Old 05-10-2021, 10:02 AM
67Fbird's Avatar
67Fbird 67Fbird is offline
Senior Chief
 
Join Date: Mar 2021
Location: GA
Posts: 465
Default

love the 041 cam...I assume its in a 400? with 1.5 rockers you will not need to worry about PTV clearance unless your running some kind of DOME piston as there is so little lift at .469. 110 ICL is a great place on average. I know back when mine ran dialing it in much lower 106 really takes away the top end charge THIS cam gives. Also with that clutch and no gears you will want to avoid a single plane intake as it will KILL anything under the 2500 rpm which is where YOU are going to be trying to get that thing rolling.

  #16  
Old 05-10-2021, 12:08 PM
pastry_chef's Avatar
pastry_chef pastry_chef is offline
Suspended
 
Join Date: May 2003
Location: Ottawa
Posts: 2,300
Default

Quote:
Originally Posted by 77 TRASHCAN View Post
In my years of reading here....109 or as close to it as possible seems like the preferred setting.
Depends on who you listen to..

Quote:
Originally Posted by Jim Hand View Post
The cam I run is a copy of the original Wolverine 5059. I had Bullet Racing grind one. The specs are:
234 intake duration with a .338 lobe
244 exhaust duration with a .340 lobe
The lobe separation is 112, with the intake indexed at 107.

  #17  
Old 05-10-2021, 12:32 PM
Formulas Formulas is offline
Ultimate Warrior
 
Join Date: Dec 2004
Posts: 2,659
Default

Bigger cams and stick shifts, = perfect place for Rhoads lifters especially if compression is conservative

2 degree advance on the cam and Rhoads lifters would significantly increase torque from idle to clutch engaging while not providing a total kill of top end charge


Last edited by Formulas; 05-10-2021 at 12:38 PM.
  #18  
Old 05-10-2021, 12:37 PM
AG's Avatar
AG AG is offline
Ultimate Warrior
 
Join Date: Feb 2000
Location: NH
Posts: 3,240
Default

I'm building a 455 for someone and just installed one with an ICL of 109.

__________________
1967 Firechicken, 499", Edl heads, 262/266@0.050" duration and 0.627"/0.643 lift SR cam, 3.90 gear, 28" tire, 3550#. 10.01@134.3 mph with a 1.45 60'. Still WAY under the rollbar rule.
  #19  
Old 05-10-2021, 03:58 PM
jeff chmura jeff chmura is offline
Senior Chief
 
Join Date: Aug 2011
Location: Jackson,New Jersey
Posts: 428
Default

Thanks Guys for all the great advice.
just an FYI... my combo..
462 ci
10.2 CR
KRE D ports poprted 290 CFM
Crane 041 clone
Rhoads V-max lifters
HS 1.5 rockers
Performer RPM manifold
sniper EFI
dual sync distributor
M23W 4 speed 2.59 1 st gear
12 bolt rear 3.31 positrac
engine runs real good, plenty of power, but i have a little off idle hesitation and being a 4 speed with the lower gear, hesitates a little, so I was thinking of degreeing the cam since I didn't. I was thinking 2-4 advance, looks like most like 2 degree advance, so I'll start there.

Thanks Jeff

  #20  
Old 05-10-2021, 04:38 PM
Scott65's Avatar
Scott65 Scott65 is offline
Ultimate Warrior
 
Join Date: Jan 2002
Location: Houston, Texas
Posts: 1,991
Default

My opinion, no more than 2 in a 455 it shouldn't need it. I believe you can tune your condition with the efi tuning manually.

__________________
'65 Tempest 467 3650# 11.30@120.31
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 10:55 AM.

 

About Us

The PY Online Forums is the largest online gathering of Pontiac enthusiasts anywhere in the world. Founded in 1991, it was also the first online forum for people to gather and talk about their Pontiacs. Since then, it has become the mecca of Pontiac technical data and knowledge that no other place can surpass.

 




Copyright © 2017