Holley adjust-a-jet kit ?
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Le Mans Master
Joined: Apr 2000
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From: B'Ville NY
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St. Jude Donor '05
Holley adjust-a-jet kit ?
Has anyone evr tried one of these? What's your opinion of this. My car still runs rich and loads up and I want to get it straightened out. Any opinions. TIA :)
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From: Waterloo ontario Canada
Re: Holley adjust-a-jet kit ? (SmokedTires)
Are we talking about the extra metering block with the adjustment on top for the main jet? If so it adds length to the carb causing problems with some air cleaners. The float nut hits on the air cleaner so the base must be hammered in for clearance. I went with the float bowls with the removable plugs to change jets without removing the bowls. After you catch on to the tricks it makes for an easy jet change. At one time I tried to buy the metering blocks where you could change the stock holley jets from the top but they are no longer available.
Get that rich thing worked out before washing the cylinder walls down. I dropped my stock 80 jets down to 72 then finally worked up to 74. You can jet quit a bit leaner then stock, richen up the power valve passage and fine tune the power valve to tip in quickly if asked.
I run a rich lean gage and on normal cruising get about 15-1 but the slightest call for power and the power valves kick in a drop it to 13-1. I get 12 mpg anytime around town.
Get that rich thing worked out before washing the cylinder walls down. I dropped my stock 80 jets down to 72 then finally worked up to 74. You can jet quit a bit leaner then stock, richen up the power valve passage and fine tune the power valve to tip in quickly if asked.
I run a rich lean gage and on normal cruising get about 15-1 but the slightest call for power and the power valves kick in a drop it to 13-1. I get 12 mpg anytime around town.
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Le Mans Master
Joined: Apr 2000
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From: B'Ville NY
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St. Jude Donor '05
Re: Holley adjust-a-jet kit ? (jimvette999)
Jim I'd love to go to EFI, just can't do it yet :( . That's a future upgrade in the future.
Norval, those are some great points that I didn't even think of. I'm also considering the fuel bowls that allow the jets to be changed out without removing. I'd like to get this thing figured out so I don't have to change plugs 3-4 times each summer. The car runs soooo strong & smooth with new plugs in it. What Rich/ Lean gage are yoiu running, & where does it hook up to ? Thanks.
[Modified by SmokedTires, 7:05 AM 6/4/2002]
Norval, those are some great points that I didn't even think of. I'm also considering the fuel bowls that allow the jets to be changed out without removing. I'd like to get this thing figured out so I don't have to change plugs 3-4 times each summer. The car runs soooo strong & smooth with new plugs in it. What Rich/ Lean gage are yoiu running, & where does it hook up to ? Thanks.
[Modified by SmokedTires, 7:05 AM 6/4/2002]
Thread Starter
Le Mans Master
Joined: Apr 2000
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From: B'Ville NY
Cruise-In III Veteran
St. Jude Donor '05
Re: Holley adjust-a-jet kit ? (SmokedTires)
Ordered an Ultralite air/fuel ratio gage, jet kit & quick change jet bowls. Hopefully this will get me where I need to be :rolleyes: .
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From: Living in the Hartland
Re: Holley adjust-a-jet kit ? (SmokedTires)
I have the quick change jet kit too. Only problem I have is that the holley jet wrench sometimes lets go of the jet in the bowl and I have to fish it out with a piece of wire or take the bowl off. I really need an a/f ratio meter but am thinking FI so I am going to wait till a make a final decision.
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From: Waterloo ontario Canada
Re: Holley adjust-a-jet kit ? (Fevre)
I get 3 plus years out of a set of plugs easily. I run them just about white. I hate rich running motors. The back of the exhaust valve gets covered it crude and the cylinder walls get washed down. I run an edelbrock rich lean gage and you must weld a bung in the exhuast pipe, no big deal for a muffler shop.
The secret with the holley quick change jet bowls is not to use the supplied installation tool to loosen or tighten the jets. It spreads the tool ruining it. I use a regular screw driver to loosen the jet, just loosen. I then install the tool to remove the jet, reinstall using the tool but never tighten, go back to the regular screw driver for tightening. I have 2 850's so that means 8 jet changes. I have got it down to a science and haven't yet dropped a jet. Once again do NOT USE THE SUPPLIED SCREWDRIVER FOR TIGHTENING OR LOOSENING , just to remove and install.
Good luck
The secret with the holley quick change jet bowls is not to use the supplied installation tool to loosen or tighten the jets. It spreads the tool ruining it. I use a regular screw driver to loosen the jet, just loosen. I then install the tool to remove the jet, reinstall using the tool but never tighten, go back to the regular screw driver for tightening. I have 2 850's so that means 8 jet changes. I have got it down to a science and haven't yet dropped a jet. Once again do NOT USE THE SUPPLIED SCREWDRIVER FOR TIGHTENING OR LOOSENING , just to remove and install.
Good luck
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Thread Starter
Le Mans Master
Joined: Apr 2000
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From: B'Ville NY
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St. Jude Donor '05
Re: Holley adjust-a-jet kit ? (Fevre)
Thanks for the tip Noval! As always your advice is appreciatied. :cheers:
I can't believe you can go 3 years before plug changes :eek: , I get about 300 miles if I'm lucky :cry . I sure hope I'm taking the right steps here to get this thing running right since I can't find anyone locally to set it up for me. I'm learning as I go here :rolleyes: .
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From: Waterloo ontario Canada
Re: Holley adjust-a-jet kit ? (SmokedTires)
I often do plug checks. Not all the plugs just a few and they never look rich. Plugs should just about last forever. New car with the platinum plugs don't need there 1st change till 160,000 km or 100,000 miles. Why can't our older cars get at least 10,000 plus miles?
Richness doesn't necessarily come from the main jets alone. It starts with the idle circuit. It is usually too rich. The idle screws should be out 1 1/2 turns. If not something else is wrong. This is ideal. Sure a little off is fine but 3 or 4 turns look else where. For rough cams I always drill a .100 hole in each throttle plate with a idle circuit. I also put a .015 wire in the idle circuit metering plate. This is recommended by holley to get better response from the idle adjustment screws.
Also if the idle plates are open too far the transfer slots add fuel to the idle mixture totally screwing it up. You can install jets in the transfer circuit but this is beyond most people at home. Get the idle down properly and the jetting will respond more. At light cruising you have the idle circuit, the transfer slots and the main jet affecting the mixture. Then along comes the power valve to really blow things.
Once again get the idle down properly before moving on to the jets
Richness doesn't necessarily come from the main jets alone. It starts with the idle circuit. It is usually too rich. The idle screws should be out 1 1/2 turns. If not something else is wrong. This is ideal. Sure a little off is fine but 3 or 4 turns look else where. For rough cams I always drill a .100 hole in each throttle plate with a idle circuit. I also put a .015 wire in the idle circuit metering plate. This is recommended by holley to get better response from the idle adjustment screws.
Also if the idle plates are open too far the transfer slots add fuel to the idle mixture totally screwing it up. You can install jets in the transfer circuit but this is beyond most people at home. Get the idle down properly and the jetting will respond more. At light cruising you have the idle circuit, the transfer slots and the main jet affecting the mixture. Then along comes the power valve to really blow things.
Once again get the idle down properly before moving on to the jets
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From: central FL, near the beach.
Re: Holley adjust-a-jet kit ? (SmokedTires)
smoked
Norval really knows Holley carbs.
But, often i find a simple problem, such as:
1. high float
2. leaking power valve
3. bad/dirty needle
4. error during rebuilding
if the above checks out good, then Norval's tips can be a lifesaver :cheers:
Norval really knows Holley carbs.
But, often i find a simple problem, such as:
1. high float
2. leaking power valve
3. bad/dirty needle
4. error during rebuilding
if the above checks out good, then Norval's tips can be a lifesaver :cheers:
Thread Starter
Le Mans Master
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From: B'Ville NY
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St. Jude Donor '05
Re: Holley adjust-a-jet kit ? (drives61)
Thanks Drives61, the engine builder is very reputable locally so I'm hoping it's not that. The carb is a year old so the needle shouldn't be dirty. I've set the floats at idle. I also tried setting the idle circuit screws to the highest possible vacuum reading, noticed that the idle transfer slot was too exposed & drilled holes into the butterflies to enable me to back the idle down some. I bought the vacuum gage and the red Holley carb book and still haven't gotten it yet. I hope the air/ fuel ratio gage will help in tuning. I also downsized the main jets from 74 which came with the carb to 70's. Not sure on the power valve but something else to look at.
I noticed that on the trip back from BG I started going through a quart of oil per tank of gas. The spark plugs were VERY loaded with carbon. Would the loaded plugs cause me to use so much oil :confused: ? The rings should be seated by now, the engine probably has 3500-4000 miles on it now.
Thanks guys :cheers: .
[Modified by SmokedTires, 9:57 AM 6/5/2002]
I noticed that on the trip back from BG I started going through a quart of oil per tank of gas. The spark plugs were VERY loaded with carbon. Would the loaded plugs cause me to use so much oil :confused: ? The rings should be seated by now, the engine probably has 3500-4000 miles on it now.
Thanks guys :cheers: .
[Modified by SmokedTires, 9:57 AM 6/5/2002]
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From: central FL, near the beach.
Re: Holley adjust-a-jet kit ? (SmokedTires)
a qt of oil per tank :eek: that may be the plug killing problem.
did you retorque the intake manifold?
as far as a dirty needle, ask any addict, once it is used, it can get dirty
did you retorque the intake manifold?
as far as a dirty needle, ask any addict, once it is used, it can get dirty
Thread Starter
Le Mans Master
Joined: Apr 2000
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From: B'Ville NY
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St. Jude Donor '05
Re: Holley adjust-a-jet kit ? (drives61)
a qt of oil per tank :eek: that may be the plug killing problem.
did you retorque the intake manifold?
did you retorque the intake manifold?
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From: central FL, near the beach.
Re: Holley adjust-a-jet kit ? (SmokedTires)
one thing you can do is remove the carb and see if oil is coating the bottom of the inside of the manifold.
and you can re-tighten the intake bolts; this needs to be done along with rechecking everything monthly until nothing is loose.
if ok, next is compression check
and you can re-tighten the intake bolts; this needs to be done along with rechecking everything monthly until nothing is loose.
if ok, next is compression check
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Re: Holley adjust-a-jet kit ? (SmokedTires)
im running a 750 holly--- the motors stroked (383)- and valves opened to 2.02 intake--488 lift cam---- im runnin a 373 gear and chambered exhausts-----to you think the carbs too big-i heard it will run better with a 650 holly-----what is ment by cylinder wash out----does this mean the extra fuel is washing the oil off the cylinder walls----------how do you check to see this is not happining-------- im hoping when this combination was built they took in effect the car was hopefully matched up---will putting in smaller jets solve the problem --im getting black soot in the exhaust tips---carl
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From: B'Ville NY
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St. Jude Donor '05
Re: Holley adjust-a-jet kit ? (drives61)
Thanks for all the help drives61 & Norval. I received the jets, gage & fuel bowl today. I asked when ordering if the gage came with everything necessary to install & was told yes. It doesn't come with the oxygen sensor as I suspected :mad , so I will have to get this before being able to have the O2 bung welded to the header collector (this moves me one step closer for the FI down the road ;) ).
Carl I would say that a 750cfm carb would be just fine on a 383. IMO when looking at a stroked small block, you can start thinking in BB terms. The .488 lift cam I would say is definitely not too big for your setup. I have the Edelbrock RPM cam on my 355 & it's .488 intake & .510 exhaust. After reading your post here, it's the first time I ever heard of cylinder wash, but when I dropped it off to the mechanic today for the state inspection, he mentioned that this may be part of my problem.
I too am gettig black soot at my exhaust tips. With the air/ fuel ratio gage, I'm hoping that I'll be able to safely lean the engine out. This should also prove worthy if I ever decide to try nitrous out with my car :yesnod: .
Carl I would say that a 750cfm carb would be just fine on a 383. IMO when looking at a stroked small block, you can start thinking in BB terms. The .488 lift cam I would say is definitely not too big for your setup. I have the Edelbrock RPM cam on my 355 & it's .488 intake & .510 exhaust. After reading your post here, it's the first time I ever heard of cylinder wash, but when I dropped it off to the mechanic today for the state inspection, he mentioned that this may be part of my problem.
I too am gettig black soot at my exhaust tips. With the air/ fuel ratio gage, I'm hoping that I'll be able to safely lean the engine out. This should also prove worthy if I ever decide to try nitrous out with my car :yesnod: .
