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New holley but bad initial hesitation

  • Thread starter Thread starter jb1dsl
  • Start date Start date Aug 14, 2006

jb1dsl

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May 24, 2004
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Marianna, Fl.
Aug 14, 2006
#1
  • Aug 14, 2006
  • #1
I have just replaced my edelbrock 600 with a holley 08475s 600. The hesitation when I punch it is terrrible. It is less than one second but it falls completely on its face, then it takes off like a rocket.I have tuned it the best I could and then let my buddy try it. He has been doing this for years. He says that I need to put in larger squirters for that initial fuel when I punch it. The carb is stock out of the box. What size come stock on this model and what size should I try first. It is a 289 with 9.8 comp, edelbrock performer rpm heads (1.90), Edelbrock performer cam, edelbrock performer intake, tri-y's, flowmaster full exhaust, c4 w/2500 stall, 3.55 rear gears, anything you need to let me know
 

Az Pete

10 Year Member
Mar 30, 2005
711
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49
Panama City, Fl.
Aug 14, 2006
#2
  • Aug 14, 2006
  • #2
I had the same problems with my 600 Holley. I had a bad stumble on hard take off plus it would almost stop if I accelerated hard from any cruising speed. Took some time but I finally bought the cam kit for the accelerator pump. $20 at most locations. It gives you 6-8 different cams to adjust how quick the acc. pump shoots the fuel. This took care of all my stuble. Local shops recommended not changing the squirters until I did this. This is on a fairly stock 302.
 

jb1dsl

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May 24, 2004
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Marianna, Fl.
Aug 14, 2006
#3
  • Aug 14, 2006
  • #3
That sounds just like the problem I have, bad at a stop and almost shut down while at any cruising speed. I will get a cam kit, which one did you end up using for your app. What are your motor specifics?
 

fasttback

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Apr 16, 2005
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Northern CA
Aug 14, 2006
#4
  • Aug 14, 2006
  • #4
Had the same problem - hesitation then it would take off. It turned out to be too much fuel coming in when the throttle was open suddenly. So, after playing with many different cam profiles and squirters I ended up with the smallest combination cam/squirter.

Basically a stock motor with headers and a four barrel carb (625 cfm). The carb is too big for the motor, but the motor will be modified soon.

When you start to switch out the carb parts, just do one change at a time and record what you are doing.
 

Az Pete

10 Year Member
Mar 30, 2005
711
18
49
Panama City, Fl.
Aug 14, 2006
#5
  • Aug 14, 2006
  • #5
I have a stock 302 as far as I know. I am running the stock squirters and the black cam. One day I may play with others to see how they are. I have just a bit of black smoke on hard throttle now that I did not have before. My problem was a lean on acceleration. It has not hurt my mileage either except now it goes when I hit it.
 

Dark Knight

Founding Member
Feb 1, 2000
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0
Chandler, Az.
Aug 14, 2006
#6
  • Aug 14, 2006
  • #6
This will help...
http://www.carbdford.com/viewtopic.php?t=4737
 

jb1dsl

Member
May 24, 2004
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Marianna, Fl.
Aug 14, 2006
#7
  • Aug 14, 2006
  • #7
what cam and squirter comes on this carb stock? Do you guys think I have toomuch fuel or not enough fuel when I punch it. I also have a k&n flow control filter system on it, it was doing this before I put it on too
 

jb1dsl

Member
May 24, 2004
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17
Marianna, Fl.
Aug 14, 2006
#8
  • Aug 14, 2006
  • #8
holley tech support said to increase the squirter one size for less than a second and two for more than asecond, does this sound right?
 

fasttback

New Member
Apr 16, 2005
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Northern CA
Aug 14, 2006
#9
  • Aug 14, 2006
  • #9
jb1dsl said:
holley tech support said to increase the squirter one size for less than a second and two for more than asecond, does this sound right?
Click to expand...

It's a starting point. I would buy the kit (as mentioned before) and you will have an assortment to choose from. Every application is different, so be prepaired to play with things. If I were to guess with your motor and a 600 cfm, I would increase squirter size (as Holley recommended) and cam size (duration and amount). Do one at a time. If it has less stumble = your going in the right direction...more stumble, switch things around.
 

jb1dsl

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Marianna, Fl.
Aug 15, 2006
#10
  • Aug 15, 2006
  • #10
Is there a kit that has an assortment of squrters also not just cams
 

Dark Knight

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Feb 1, 2000
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0
Chandler, Az.
Aug 15, 2006
#11
  • Aug 15, 2006
  • #11
http://www.holley.com/data/TechService/Technical/Carb Numerical Listing.pdf

You'll need the full model number. I'd change pump cams before messing with the squirter size. I went to the black cam too.
 

jb1dsl

Member
May 24, 2004
566
0
17
Marianna, Fl.
Aug 15, 2006
#12
  • Aug 15, 2006
  • #12
dark knight
did you change your squirter size too or just the cam. Is a black cam less or more than what comes in this carb stock
 

jb1dsl

Member
May 24, 2004
566
0
17
Marianna, Fl.
Aug 16, 2006
#13
  • Aug 16, 2006
  • #13
The squirter in the carb is a .031 the next size is a .032 then a .035, do you think I should order the .035 instead of the .032 if I order one because of the very slight change
 

Dark Knight

Founding Member
Feb 1, 2000
2,578
0
0
Chandler, Az.
Aug 16, 2006
#14
  • Aug 16, 2006
  • #14
I just changed the cam.. I had the advantage of messing with it on a dyno to see if it was going lean or not..

What color cam do you have now? And have you adjusted the lever on the pump at all?
 

mfp4073

Founding Member
Mar 14, 2001
387
0
38
Hells Ditch, FL
Aug 16, 2006
#15
  • Aug 16, 2006
  • #15
yeah, thats part of the voodoo of tuning a holley. I forget what I went with color wise, but I used the biggest cam and bigger squirters (I also messed with my jetting). My manual trasmission car will respond immediatly to a stab of the throttle at any speed to the point of breaking the tires loose in 2nd gear at 30-40mph or chirping the tires in 3rd gear at 55 both with no clutch. Its doable! Just keep trying
 

jb1dsl

Member
May 24, 2004
566
0
17
Marianna, Fl.
Aug 16, 2006
#16
  • Aug 16, 2006
  • #16
i have whatever cam comes on this model stock. I have not adjusted the lever yet, any pointers
 

mfp4073

Founding Member
Mar 14, 2001
387
0
38
Hells Ditch, FL
Aug 16, 2006
#17
  • Aug 16, 2006
  • #17
A lot is trial and error. Up the squirter cam, see how it does, lower the squirter cam, see how it does, up the jets, see how it does.......im telling you, one of the best tools to tune a holley is a chicken foot! BUT when they get dialed in....watch out!
 
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