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I want to know about cam surge

  • Thread starter Thread starter Joey7508
  • Start date Start date Oct 23, 2009
J

Joey7508

Member
Oct 23, 2005
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17
Kerrville TX
Oct 23, 2009
#1
  • Oct 23, 2009
  • #1
I have been reading about cam surge. What I have read has mostly been on efi GM products. It is explained as a slight surge while driving under 2000k that is not present at highway speeds or any other time. A lean condition from running a bigger cam mild to med. ON some of there forums they say a tune can minimalize it. I have just been googleing it. Don't own a GM product. Just wondering if any one here has had that problem and determined it to be cam surge? I am having that problem on my 5.0 right now. And yes I checked the surging idle check list, pulled codes (11), checked for vacuum leaks. Iwould love to hear ideas but I mostly want to know about cam surge. Is something that really requires tuning out or just a name for "I can't fix my surge so I'll call it cam surge".
One other thing I was wondering is would having a f303 cam and a gear ratio like 3.08 cause a surge issue? I know it might get in the right rpm quicker with a better gear but would or could it make it surge below 2000K?
 

Celeb

20+ Year Stangneter
Sep 8, 2002
736
13
59
Here and there
Oct 23, 2009
#2
  • Oct 23, 2009
  • #2
When you say surge, do you mean like erratic idling or low rpm cam bucking?
 
J

Joey7508

Member
Oct 23, 2005
198
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17
Kerrville TX
Oct 25, 2009
#3
  • Oct 25, 2009
  • #3
low rpm bucking. But not violent.
 

Celeb

20+ Year Stangneter
Sep 8, 2002
736
13
59
Here and there
Oct 25, 2009
#4
  • Oct 25, 2009
  • #4
Mine does that. But I spend alot of time in low rpms in traffic plus my car isn't geared right for it. I doubt you're going to be able to tune that out, short of getting lower gears or swapping cams.

Are you running an F cam?
 

cenok is family

15 Year Member
Jun 25, 2003
1,409
69
79
Norman, Ok
Oct 25, 2009
#5
  • Oct 25, 2009
  • #5
my car used to do that. except mine was linked to a rich condition/disconnected MAF sensor. since fixed the issue and it no longer does it.
 
J

Joey7508

Member
Oct 23, 2005
198
0
17
Kerrville TX
Oct 26, 2009
#6
  • Oct 26, 2009
  • #6
swapped gears this weekend. Still surges in same rpm area, but the gears make all the difference performance wise. went from 3.08 to 4.10 for now. I will go back to 3.08-3.27 when I sort out the surge and get my turbo set up back on. I have alot of extra stuff sitting around so ity doesn't cost me anything but time. Oh and I run a vipert56. But just wanted to say it didn't change the surge.
 

liljoe07

5 Year Member
Feb 18, 2009
1,622
363
124
Cartersville,Ga
Oct 26, 2009
#7
  • Oct 26, 2009
  • #7
Where is the timing set at?
 
J

Joey7508

Member
Oct 23, 2005
198
0
17
Kerrville TX
Oct 27, 2009
#8
  • Oct 27, 2009
  • #8
12*
 
J

Joey7508

Member
Oct 23, 2005
198
0
17
Kerrville TX
Oct 27, 2009
#9
  • Oct 27, 2009
  • #9
tried it at 10* didn't seem to make a difference. Here is somethign I have figured out. Is that on a cleared computer it does not seem to be there. Once it relearns it seems to do it? Any ideas on that?
 

stykthyn

I want to measure mine. It doesn't look that tall.
15 Year Member
Jul 6, 2006
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Oct 27, 2009
#10
  • Oct 27, 2009
  • #10
I used to have that, but it was timing issue. finally found the sweet spot and it went away
 

liljoe07

5 Year Member
Feb 18, 2009
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Cartersville,Ga
Oct 27, 2009
#11
  • Oct 27, 2009
  • #11
Whats the manifold vacuum at idle?
 
J

Joey7508

Member
Oct 23, 2005
198
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17
Kerrville TX
Oct 28, 2009
#12
  • Oct 28, 2009
  • #12
13
 

liljoe07

5 Year Member
Feb 18, 2009
1,622
363
124
Cartersville,Ga
Oct 28, 2009
#13
  • Oct 28, 2009
  • #13
E-cam?
 
J

Joey7508

Member
Oct 23, 2005
198
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17
Kerrville TX
Oct 29, 2009
#14
  • Oct 29, 2009
  • #14
f303 1.6 rockers
 

liljoe07

5 Year Member
Feb 18, 2009
1,622
363
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Cartersville,Ga
Oct 29, 2009
#15
  • Oct 29, 2009
  • #15
Posted via Mobile Device

Vacuum is kinda low for the F-303 cam. I still have that cam. I pulled 17"-18" of vacuum with it. Maybe the rockers are little to tight.
 
J

Joey7508

Member
Oct 23, 2005
198
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17
Kerrville TX
Oct 30, 2009
#16
  • Oct 30, 2009
  • #16
I'll try the rockers this weekend see what happens. I'll let you know thanks for the suggestion. I have been thinking about that but didn't know what other people got for vacuum on that cam.
 
M

mike0227

Member
Dec 19, 2004
53
0
7
Houston Texas
Oct 30, 2009
#17
  • Oct 30, 2009
  • #17
CAM SURGE

I have the same problem and have been trying to tune it out of the 140-1600 RPM range. Other than that the car runs and idles fine thanks to the tweecer.

Please let me know if you find solution and I will do likewise. This has been going on for years. P.S. I use F-Cam and vacuum is about 13-14.
 
J

Joey7508

Member
Oct 23, 2005
198
0
17
Kerrville TX
Nov 1, 2009
#18
  • Nov 1, 2009
  • #18
mike0227 I read your post a little late, I readjusted my valves just to make sure the only thing I had not checked twice. Vacuum still 13-14 no change. I will know more about it. I won't give up till I figure it out.
 
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