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Should I scap the holley for an edelbrock??

  • Thread starter Thread starter PickupMan
  • Start date Start date Feb 13, 2004

PickupMan

Founding Member
Jan 30, 2000
403
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Hazleton, Pa
Feb 13, 2004
#1
  • Feb 13, 2004
  • #1
I'm about to throw this brand new holley out the window!!!!! The front bowl keeps overfilling. I've done everything to it and still no luck. I was thinking of going with the new edelbrock AVS series carb. I have a 289 with a mild cam, headers, intake and some head work. I have a holley 650 double pumper right now and thinking of the 650 thunder series AVS. Is anyone using this carb? If so do you like it? What carb would you run?
 
S

sportsroof69

Founding Member
May 21, 2002
231
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16
Huntsville, AL
Feb 13, 2004
#2
  • Feb 13, 2004
  • #2
Have you tried a fuel pressure regulator? I had to lower my pressure down to 6.5 lbs to keep the bowls from overfilling. Check your floats to make sure they aren't filling with gas, too.
 

PickupMan

Founding Member
Jan 30, 2000
403
7
28
50
Hazleton, Pa
Feb 13, 2004
#3
  • Feb 13, 2004
  • #3
This is true!!!! I did think of the regulator but my cousin is running the same carb with no problems. It's a stock pump. I'll pick one up tomorrow and see what happens. The floats are brand new! Plastic floats and they are fine. Hopfully the pressure regulator will work. What's the best way to tune this carb? It's running really rich.
 
L

Lswhat

New Member
Feb 9, 2004
126
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Orlando
Feb 13, 2004
#4
  • Feb 13, 2004
  • #4
well i never did like my edelbrock because it left so much to be desired from my motor i am now running a really expensive holley that has all the good stuf in it and let me tell it makes a really big diffrence in performance. as far as tunning i cant tell u how to on a holley but i can tune the hell out of an edelbrock.
 

pabear89

Active Member
Apr 15, 2003
2,126
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46
High in the Hills of So Ca with the Voices in My H
Feb 13, 2004
#5
  • Feb 13, 2004
  • #5
Brand new and the front floods?

Recheck the needle setting.
If you run the needle seat too far down,
The needle will stick the first time the level drops and it has to rise.

PB
 
D

D.Hearne

New Member
Sep 29, 2000
11,730
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south louisiana
Feb 14, 2004
#6
  • Feb 14, 2004
  • #6
It should be running rich with all that extra fuel being dumped into the throttle bores. Wait on tuning til you get the floats set. Easiest way to do the floats is to remove the bowls and set them while holding them upside down. The only other adjustment that should be necessary is the idle and idle mixture screws. The factory jetting should be fine with your combo. I'd try the regulator too, stock pumps are known to put out too much pressure.
 
S

sportsroof69

Founding Member
May 21, 2002
231
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16
Huntsville, AL
Feb 14, 2004
#7
  • Feb 14, 2004
  • #7
Can you turn the idle screws all the way in without killing the engine? If so, you may have a blown power valve, cracked power valve gasket, damaged O-ring on the accel. pump transfer tube (between the main body and metering block), the gasket between the metering block and main body may not be sealing due to an uneven sealing surface (requires filing the main body gasket surface flat), or the metering block may have an internal leak. I bought a brand new 600 that had a bad metering block that caused it to run rich all the time. I swapped it for an old block and the problem went away. Double pumpers have 2 power valves, correct? You may try installing a plug in place of the second valve.
 

PickupMan

Founding Member
Jan 30, 2000
403
7
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Hazleton, Pa
Feb 14, 2004
#8
  • Feb 14, 2004
  • #8
Yes it is the front bowl that was giving me the trouble. The rear did it as well but it stopped. I have the needle down past the adjusting nut. I have to shut the car down removed the float adjusting nut and turn it by hand. I'm going to go get a pressure regulator today and see what happens. How much pressure should be at the carb??? 6-7psi?

Thanks!
 
D

D.Hearne

New Member
Sep 29, 2000
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south louisiana
Feb 14, 2004
#9
  • Feb 14, 2004
  • #9
There's no O ring between the main body and metering block on a 600 DP, just the gasket performs this function. Also most DP's don't have secondary power valves. Pressure at the carb should be around 5 psi
 

12sec67

Active Member
Oct 6, 2003
1,301
1
36
47
San Diego, Ca
Feb 14, 2004
#10
  • Feb 14, 2004
  • #10
make sure the powervalve gasket is in place and not broken, then check the needle and seat- is the o-ring on the the needle and seat -piece on top, that you can pull out of the carb when in place.
 

pabear89

Active Member
Apr 15, 2003
2,126
0
46
High in the Hills of So Ca with the Voices in My H
Feb 14, 2004
#11
  • Feb 14, 2004
  • #11
PickupMan said:
Yes it is the front bowl that was giving me the trouble. The rear did it as well but it stopped. I have the needle down past the adjusting nut. I have to shut the car down removed the float adjusting nut and turn it by hand. I'm going to go get a pressure regulator today and see what happens. How much pressure should be at the carb??? 6-7psi?

Thanks!
Click to expand...


that far down and the needle with bind in the valve channel when the float tries to raise it.
The needle assy should be near the top of the locknut +/- a small amount.
set by backing them out to level, Then adjusting the Fuel level to just at the bottom of the sighthole.


PB
 

restomodracing

New Member
Feb 12, 2004
8
0
0
73
West Hills, CA
www.yamaberacing.com
Feb 14, 2004
#12
  • Feb 14, 2004
  • #12
Sounds like a small particle is on the needle. I used to have that happen because my fuel tank was dirty. The particle is soooo small that you need a magnifying glass to see it. By the way, I even installed a in line fuel filter and it still would happen. Over time as the tank was cleaned out it stopped happening.
 

HistoricMustang

Active Member
Apr 11, 2003
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77
Confederate States of America
www.historicmustang.com
Feb 14, 2004
#13
  • Feb 14, 2004
  • #13
Been using a Holley 650 for years on my race rod with no problems. Even on the high banks. Believe D. Hearne has you going the the correct direction.

HistoricMustang
www.historicmustang.com
 
D

D.Hearne

New Member
Sep 29, 2000
11,730
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south louisiana
Feb 14, 2004
#14
  • Feb 14, 2004
  • #14
I've seen that many times the needle screw assembly is well down inside the nut when adjusted correctly. Like maybe halfway into the nut.
 

PickupMan

Founding Member
Jan 30, 2000
403
7
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50
Hazleton, Pa
Feb 14, 2004
#15
  • Feb 14, 2004
  • #15
Got the regulator today. I picked it up at the local speed shop for a pretty good price. I think I'm getting old...the slaes person at the shop knew NOTHING about a carburated car. How do you work at a speed shop and not know anything about carbs?? Anyway. Installed the regulator with a guage and the pressure was 8psi. Lowered it to 5 and set the floats. I had to raise the foats a little and now it seems to be working properly. Haven't had a chance to drive it and see if it happens again but so far I'm pleased. Glad to see that the floats have some adjustment now. Before they were way too low. Thanks again for all your help. Guess I'll be keeping the holley for a while!
 

PickupMan

Founding Member
Jan 30, 2000
403
7
28
50
Hazleton, Pa
Feb 16, 2004
#16
  • Feb 16, 2004
  • #16
WOW WOW WOW!!!! Well I took the car for a ride today to see if the regulator did the job. WEll I must say the the stang NEVER ran like that before!!! It pulled so hard through all the gears I was afraid to shift to the next gear!! Before when I would floor it the power would just flaten out. Now when the secondaried kick in it's like a rocket. Thaks again everyone for all your help!!!!!
 
D

D.Hearne

New Member
Sep 29, 2000
11,730
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south louisiana
Feb 16, 2004
#17
  • Feb 16, 2004
  • #17
PickupMan said:
WOW WOW WOW!!!! Well I took the car for a ride today to see if the regulator did the job. WEll I must say the the stang NEVER ran like that before!!! It pulled so hard through all the gears I was afraid to shift to the next gear!! Before when I would floor it the power would just flaten out. Now when the secondaried kick in it's like a rocket. Thaks again everyone for all your help!!!!!
Click to expand...
Glad to hear you've got it straightened out. Have fun but be careful
 
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