Holley Adjust-a-Jet kits, do they work??
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Holley Adjust-a-Jet kits, do they work??
I've considered getting the Holley Adjust-a-jet kit. You know, the plates with an adjustment screw on top, that fits between the metering block and float bowl.
Anybody have a set on their carb??
I've seen a new billet setup from another manufacturer, but theirs cant be tuned with the motor running.
Is the fuel delivered equally between both sides? Is that necessarily a good thing??
Can the plate be adjusted while the motor is running? (I think so)
Does the accelerator pump need re-tuning after switching to the longer arm??
Anybody have a set on their carb??
I've seen a new billet setup from another manufacturer, but theirs cant be tuned with the motor running.
Is the fuel delivered equally between both sides? Is that necessarily a good thing??
Can the plate be adjusted while the motor is running? (I think so)
Does the accelerator pump need re-tuning after switching to the longer arm??
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Re: Holley Adjust-a-Jet kits, do they work?? ('75 383 ElkGrove)
It seems almost no one uses them. Maybe it's the cost. They seem intriguing, though, you could tune without getting gas everywhere.
My engine builder has had some customers with them on their carbs. He said they work fine, but he's not interested in using them.
My engine builder has had some customers with them on their carbs. He said they work fine, but he's not interested in using them.
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From: delmont pa
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Re: Holley Adjust-a-Jet kits, do they work?? ('75 383 ElkGrove)
the big problem is you can no longer use a drop down air cleaner base because the added length of the float bowls will prevent it. they are great for dyno tuning :chevy
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Re: Holley Adjust-a-Jet kits, do they work?? (clem zahrobsky)
the big problem is you can no longer use a drop down air cleaner base because the added length of the float bowls will prevent it. they are great for dyno tuning :chevy
With only about .30" between my air cleaner lid and hood, I don't think I can use the kit, unless I sink some more money for a new air filter.
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Re: Holley Adjust-a-Jet kits, do they work?? (clem zahrobsky)
A little creative hammer work is required to get the air cleaner to fit. I looked at these adjust a jet kit but worried that I couldn't accurately tell what I had in the carb. If I wanted to drop the jetting a step or two I want to know for sure I dropped that amount and not relie on clicks. I tried to buy the jet plates that allowed you to use standard holley jets and make jetting changes while the engine was idleing but the company went out of business do to a law suit.
Also when I found out I would have to hammer and clearance path into my chrome dropped base air cleaner I went for the holley quick change bowls.
Also when I found out I would have to hammer and clearance path into my chrome dropped base air cleaner I went for the holley quick change bowls.
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Re: Holley Adjust-a-Jet kits, do they work?? ('75 383 ElkGrove)
Another revelation...
It seems that the $80 kit does not include parts necessary to upgrade both the primaries AND secondaries.
It looks like you've got to buy 2 kits to completely modify the carb.
I guess I might be able to get by on just having one set on the primaries to tune in the driveability, and just do the secondaries the ol' fashioned way.
Hmmmm.
Decisions, decisions...
On one hand, keep everything the way it currently is, but continue tuning it 'till I get it right.
Or, the other hand, spend around $200 for adjust-a-jet kits, x-tra gaskets, and new dual feed fuel line.
Either way, I probably won't be able to REALLY tune her 'till I get my O2 sensor and gauge installed.
It seems that the $80 kit does not include parts necessary to upgrade both the primaries AND secondaries.
It looks like you've got to buy 2 kits to completely modify the carb.
I guess I might be able to get by on just having one set on the primaries to tune in the driveability, and just do the secondaries the ol' fashioned way.
Hmmmm.
Decisions, decisions...
On one hand, keep everything the way it currently is, but continue tuning it 'till I get it right.
Or, the other hand, spend around $200 for adjust-a-jet kits, x-tra gaskets, and new dual feed fuel line.
Either way, I probably won't be able to REALLY tune her 'till I get my O2 sensor and gauge installed.
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From: Waterloo ontario Canada
Re: Holley Adjust-a-Jet kits, do they work?? ('75 383 ElkGrove)
How about just replacing the float bowls with the quick change jet plugs. You still have to drain the gas from the float bowls but there are 2 brass plugs in the float bowl and a special jet removal tool that allows you to remove and replace jets without taking the float bowls off and destroying the gaskets. After a little practice it becomes easy for a quick jet change and everything fits like stock.
You can see one of the jet plugs on the end of the carb in this pictures. It is near the fuel inlet line.
You can see one of the jet plugs on the end of the carb in this pictures. It is near the fuel inlet line.
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Re: Holley Adjust-a-Jet kits, do they work?? (norvalwilhelm)
I've seen those quick change kits in Jeg's and such...
I don't trust myself with gasoline over a hot engine.
I would still pull the carb, etc, so there's not much differance except the four bolts that hold the bowls and meter block in place.
Another thing is that I've experienced the jet up/ down with no change in performance problem. I'vd seen those close tolerance holley jets, but the kits are way more ex$pen$ive than the standard jets.
On Friday, I received my new summit brand adjustable fuel line (the one with the in-line filter and gauge) and it looks like this would do the trick to feed a carb with two of the adjust-a-jet kits installed. I needed a new fuel line, gauge and filter anyway, so I bought this one just in case I decide to get 2 of these kits.
Soon, I will try to contact holley, and try to get some spec's on the thickness of the extra blocks. That way I can take my extra air cleaner base, and try to pound out enough to clear the whole setup. If I can't get the base to work, I'll throw it, and the idea of the adjust-a-jets, in the trash.
BTW the summit fuel line is waaay better in terms of strength and versitility. Not to mention the fuel filtering. I've gone through 3 of those $14 chromed copper and/or brass fuel lines in the 5 years I've had my 'vette.
I don't trust myself with gasoline over a hot engine.
I would still pull the carb, etc, so there's not much differance except the four bolts that hold the bowls and meter block in place.
Another thing is that I've experienced the jet up/ down with no change in performance problem. I'vd seen those close tolerance holley jets, but the kits are way more ex$pen$ive than the standard jets.
On Friday, I received my new summit brand adjustable fuel line (the one with the in-line filter and gauge) and it looks like this would do the trick to feed a carb with two of the adjust-a-jet kits installed. I needed a new fuel line, gauge and filter anyway, so I bought this one just in case I decide to get 2 of these kits.
Soon, I will try to contact holley, and try to get some spec's on the thickness of the extra blocks. That way I can take my extra air cleaner base, and try to pound out enough to clear the whole setup. If I can't get the base to work, I'll throw it, and the idea of the adjust-a-jets, in the trash.
BTW the summit fuel line is waaay better in terms of strength and versitility. Not to mention the fuel filtering. I've gone through 3 of those $14 chromed copper and/or brass fuel lines in the 5 years I've had my 'vette.
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Re: Holley Adjust-a-Jet kits, do they work?? ('75 383 ElkGrove)
... just spoke to Holley tech line.
They told me that there's been a couple differant designs used with these kits.
The older plates are .575" thick.
The plates they currently sell are 1/2" thick.
Meanwhile, I took a ball peen hammer to an extra air cleaner base, and made me some extra room.
I'm almost sure that I've made enough clearance, but I wont know 100% 'till I receive my kits.-- Yeah, I decided to buy them anyway.
I haven't got the car started yet, but when I do, and install the kits, I'll keep you guys informed to tell you if it was worth the $$.
They told me that there's been a couple differant designs used with these kits.
The older plates are .575" thick.
The plates they currently sell are 1/2" thick.
Meanwhile, I took a ball peen hammer to an extra air cleaner base, and made me some extra room.
I'm almost sure that I've made enough clearance, but I wont know 100% 'till I receive my kits.-- Yeah, I decided to buy them anyway.
I haven't got the car started yet, but when I do, and install the kits, I'll keep you guys informed to tell you if it was worth the $$.
