Give me your e-mail adress and I will send you a word-document "Holley stumble issues" written by Lars. Also if anybody else will have this document, give me your e-mail adress.
Carb Bog
Thread Starter
Drifting
Joined: Jan 2002
Posts: 1,645
Likes: 11
From: Schaumburg IL
Carb Bog
For a change this is not about a Q-Jet bog. I have a Holley Avenger 770cfm on a 73-454 using an adaptor. In the past it has run well without this problem. Today it idled ok, and would accelerate smooth if you ease it up in speed. Key is ease it up. If you jump on it say 3/4 throttle - it will sputter and seem to bog terrible like it has just run out of fuel and is only being fed 1/2 of what it needs. Checked the float levels and they were still ok. No other changes on engine. Pulled the bowl filters and they seemed to blow air throught them ok.
Removed the Holley and put an Edelbrock 1411 on the engine, did not change timing or anything fuel related except the fuel line to the carb. The carb came right up running, idled fair, tweaked the mixture and down the road I went. No hesitation, bog, just smooth acceleration.
Any ideas on the problem with the Holley or where to start?
Removed the Holley and put an Edelbrock 1411 on the engine, did not change timing or anything fuel related except the fuel line to the carb. The carb came right up running, idled fair, tweaked the mixture and down the road I went. No hesitation, bog, just smooth acceleration.
Any ideas on the problem with the Holley or where to start?
Drifting
Joined: Jul 1999
Posts: 1,542
Likes: 43
From: Plano TX
When you put the Edelbrock on did you let the engine fully warm up and take it for a drive? Reason for asking is the HEI module can fail which causes the same problem once the dist housing gets to full engine temp.
Pro
Joined: Aug 2008
Posts: 744
Likes: 19
From: Salzburg Austria
Thread Starter
Drifting
Joined: Jan 2002
Posts: 1,645
Likes: 11
From: Schaumburg IL
Two replies
I would love to have a hood that cleared a Holley and a good dual plane intake, but not in the card now after a paint job this summer. Is there a reason for asking or do you have insight the adaptor tends to cause problems???
I will try looking down the throat next week when I put it back on.
thanks JP
I would love to have a hood that cleared a Holley and a good dual plane intake, but not in the card now after a paint job this summer. Is there a reason for asking or do you have insight the adaptor tends to cause problems???
I will try looking down the throat next week when I put it back on.
thanks JP
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Race Director
Joined: Apr 1999
Posts: 11,520
Likes: 13
From: CORVETTE 77 385 C.I. TEXAS
Considering the entire flow path & limited clearance it would be better w/o an adapter. 383+ can handle a single plane easier than small engines. Cadillac even used a single plane intake manifold on 368 & 425!
Drifting
Joined: Mar 2011
Posts: 1,271
Likes: 1
From: PA
Two replies
I would love to have a hood that cleared a Holley and a good dual plane intake, but not in the card now after a paint job this summer. Is there a reason for asking or do you have insight the adaptor tends to cause problems???
I will try looking down the throat next week when I put it back on.
thanks JP
I would love to have a hood that cleared a Holley and a good dual plane intake, but not in the card now after a paint job this summer. Is there a reason for asking or do you have insight the adaptor tends to cause problems???
I will try looking down the throat next week when I put it back on.
thanks JP
Drifting
Joined: Mar 2011
Posts: 1,271
Likes: 1
From: PA
Ok. Well that's a mystery for sure. If it worked fine in the past and now you get stumble I would suspect a fuel delivery issue (including passages in the carb restricted) or a vacuum leak. Maybe it was a leak at the base of the carb and the edelbrock carb was torqued better. I'd rebuild the Holley and try it again before I went farther. Is your vac reading the same as in the past ?
Thread Starter
Drifting
Joined: Jan 2002
Posts: 1,645
Likes: 11
From: Schaumburg IL
Ganey,
considering I have a BB the choices are limited without changing the hood and that is what I trying to avoid. Hence, I think the only single plane available to me is the Torker II which can handle the Spread or square bores.
I have a Q-Jet that is a rebuilt stock for the engine. However, it has the divorced choke and in cold weather her in ILL it opens too early before the mega iron is warm to accept the rush of cold air. That is the reason I have tried to go with the electric choke models for now. Thanks
JP
considering I have a BB the choices are limited without changing the hood and that is what I trying to avoid. Hence, I think the only single plane available to me is the Torker II which can handle the Spread or square bores.
I have a Q-Jet that is a rebuilt stock for the engine. However, it has the divorced choke and in cold weather her in ILL it opens too early before the mega iron is warm to accept the rush of cold air. That is the reason I have tried to go with the electric choke models for now. Thanks
JP
Thread Starter
Drifting
Joined: Jan 2002
Posts: 1,645
Likes: 11
From: Schaumburg IL
Boltnut - yes for all purposes the vacuum reading is the same for both the Holley and the Edelbrock, right at 15-16". Maybe the thought of sealing etc has merit.
I agree that something took place in the Hollley like you say some plugs or ?? I think the idea to take it apart and clean well is warranted.
What would be the affect of a blown or plugged power valve? Would this cause a lack of fuel flow when needed?
for now until I get the Holley apart and cleaned I guess I use the Edelbrock.
I agree that something took place in the Hollley like you say some plugs or ?? I think the idea to take it apart and clean well is warranted.
What would be the affect of a blown or plugged power valve? Would this cause a lack of fuel flow when needed?
for now until I get the Holley apart and cleaned I guess I use the Edelbrock.
Drifting
Joined: Mar 2011
Posts: 1,271
Likes: 1
From: PA
http://www.holley.com/data/TechServi...wer_valves.pdf
I think I blown power valve would give you a super rich idle and unresponsive idle mix screws.
Did you see any white or red deposits in your fuel bowls ?
I think I blown power valve would give you a super rich idle and unresponsive idle mix screws.
Did you see any white or red deposits in your fuel bowls ?
Drifting
Joined: Mar 2011
Posts: 1,271
Likes: 1
From: PA
Thread Starter
Drifting
Joined: Jan 2002
Posts: 1,645
Likes: 11
From: Schaumburg IL
Pulled the bowls and they were nice and shiney no white or red or anthing else inside. Sprayed carb cleaner in every orfice I could, now bowl gaskets, cked the floats dry for centered in the bowl - ok for now. Will reinstall on Monday and see what happens.
This is strange as it is more than a bog but rather like you ran out of 1/2 the fuel you need when accelerating hard. Yet same fuel line and all else the same and the Edelbrock accelerates fine.
This is strange as it is more than a bog but rather like you ran out of 1/2 the fuel you need when accelerating hard. Yet same fuel line and all else the same and the Edelbrock accelerates fine.
Thread Starter
Drifting
Joined: Jan 2002
Posts: 1,645
Likes: 11
From: Schaumburg IL
Gunther,
Cked the acc pump and it does move the arm with the throttle so now when I put the Holley back on in the next day or so, I will ck that the squirters are both working at the slightest touch of the throttle. Thx
JP
Cked the acc pump and it does move the arm with the throttle so now when I put the Holley back on in the next day or so, I will ck that the squirters are both working at the slightest touch of the throttle. Thx
JP