Holley 4165/6210 Question
Thread Starter
Melting Slicks
Joined: May 2007
Posts: 3,246
Likes: 4
From: Bay Area CA
Holley 4165/6210 Question
I've got a Holley 4165 that was giving me trouble. I looked at the Holley Docs, the put together shows a Power Valve in the Secondary metering bolck. The Carb i have doesn't have one, just metal, unmachined, closed. Is this correct, or a factory error?
Burning Brakes
Joined: Aug 2005
Posts: 1,164
Likes: 1
From: Europe, France
As far as I know, 4165 have a secondary metering plate, and not block. The difference is that you don't have jets on a plate and you have on a block. And none of them have a secondary power valve... I don't even have one on my 4150...
But I will have a look at my Holley books to be sure...
But I will have a look at my Holley books to be sure...
Last edited by 73StreetRace; Jul 28, 2009 at 05:53 AM.
Burning Brakes
Joined: Aug 2005
Posts: 1,164
Likes: 1
From: Europe, France
Oops ! My mistake ! I mixed up 4160 and 4165 data !
My manual says that there are two types of 4165 carburetors : Standard ( normal replacement ) and high performance ( emission-design / street performance ).
But the manual only shows one exploded view for 4165/4175 carbs.
And effectively, there are two metering blocks ( so, 4 main jets ), and two power valves on the picture.
The shown carb is a double pumper with choke.
Do you have this type of carb ? Holley inline catalog shows 3 types of 6210 : 6210-1, -2, -3 with different parts list.
Check the number stamped on your secondary metering block.
My manual says that there are two types of 4165 carburetors : Standard ( normal replacement ) and high performance ( emission-design / street performance ).
But the manual only shows one exploded view for 4165/4175 carbs.
And effectively, there are two metering blocks ( so, 4 main jets ), and two power valves on the picture.
The shown carb is a double pumper with choke.
Do you have this type of carb ? Holley inline catalog shows 3 types of 6210 : 6210-1, -2, -3 with different parts list.
Check the number stamped on your secondary metering block.
Last edited by 73StreetRace; Jul 28, 2009 at 08:40 AM.
Burning Brakes
Joined: Aug 2005
Posts: 1,164
Likes: 1
From: Europe, France
Holley catalog says :
4165 - R6210-3 - 650cfm
Primary Main Jets : 122-602
Secondary Main Jets : 122-83
Power valve(s) : 125-85 ( 8,5" Hg )
Primary Pump Nozzle Size : 0.025"
Secondary Pump Nozzle Size : 0,037"
Primary Metering Block : N/S ( Not Serviced )
Secondary Metering Block : N/S ( Not Serviced )
I would say N/GH : Not a Great Help.... 
4165 - R6210-3 - 650cfm
Primary Main Jets : 122-602
Secondary Main Jets : 122-83
Power valve(s) : 125-85 ( 8,5" Hg )
Primary Pump Nozzle Size : 0.025"
Secondary Pump Nozzle Size : 0,037"
Primary Metering Block : N/S ( Not Serviced )
Secondary Metering Block : N/S ( Not Serviced )
I would say N/GH : Not a Great Help....
Last edited by 73StreetRace; Jul 29, 2009 at 02:36 AM.
Thread Starter
Melting Slicks
Joined: May 2007
Posts: 3,246
Likes: 4
From: Bay Area CA
No worries, i called Holley earlier, the guy said no power valve. Figured. It's a good carb, but stalled on the gas being forced forward- hard braking, steep hills, fast U turns. Guy said it was probably the rear fuel level too high. Already put it back together w/new gaskets and power valve, plugged the rear fuel inlet,, will test it out tomorrow. C. 
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Burning Brakes
Joined: Aug 2005
Posts: 1,164
Likes: 1
From: Europe, France
Yes, this is what I found in another Holley repair book :
4165 Features :
"...Backfire protection for the power valve was added in 1992..."
They don't say "valves", so I suppose there should be only one...
But this doesn't explain why the exploded view shows two
4165 Features :
"...Backfire protection for the power valve was added in 1992..."
They don't say "valves", so I suppose there should be only one...
But this doesn't explain why the exploded view shows two
Burning Brakes
Joined: Aug 2005
Posts: 1,164
Likes: 1
From: Europe, France
No worries, i called Holley earlier, the guy said no power valve. Figured. It's a good carb, but stalled on the gas being forced forward- hard braking, steep hills, fast U turns. Guy said it was probably the rear fuel level too high. Already put it back together w/new gaskets and power valve, plugged the rear fuel inlet,, will test it out tomorrow. C.
Last edited by 73StreetRace; Jul 29, 2009 at 03:08 AM.
Thread Starter
Melting Slicks
Joined: May 2007
Posts: 3,246
Likes: 4
From: Bay Area CA
Yea, it only happened with the Holley though, the Rochester is fine, plus, SF bay area weather isn't exactly surfing weather either. 
Anyway,, thought I'd like to try the Holley, i mean the Q-Jet is a good carb,, but sometimes i think there's just too much going on with them. I like the Holley secondaries,, Mechanical, and no air plates,, Just get it and GO!!! 
Anyway,, thought I'd like to try the Holley, i mean the Q-Jet is a good carb,, but sometimes i think there's just too much going on with them. I like the Holley secondaries,, Mechanical, and no air plates,, Just get it and GO!!!
Melting Slicks
Joined: Jun 2003
Posts: 2,802
Likes: 241
From: Niles, MI
Thread Starter
Melting Slicks
Joined: May 2007
Posts: 3,246
Likes: 4
From: Bay Area CA
Melting Slicks
Joined: Jun 2003
Posts: 2,802
Likes: 241
From: Niles, MI
With the recommendations made, were you able to get the carb running well, what do you think of the 64 jets, and 4.5 power valve? I've got a 6.5 i might try instead of the 8.5. what cam are you running? Were you able to cure the stalling problem on hard braking with the hoses?
I just installed longer vent tubes; I didn't connect them with fuel line. The tubes are about an inch longer than stock; the tops are about a quarter inch under the air cleaner lid. It has cured the stalling issue.
Here's a link to a page that addresses the fuel slosh issue in detail. Offroad tricks for Holley 4 barrel carbs
Burning Brakes
Joined: Aug 2005
Posts: 1,164
Likes: 1
From: Europe, France
Thanks for this interesting link.
I knew that trick for offroad use but had never seen how to do it with pictures...
Just one thing : if you don't want to take a chance and ruin your carb, you can try the same trick but only push small lengths of rubber hose on the carb fuel vent tubes and on the U-shape copper tube ( just cut the legs shorter ).
No drilling, easy to do, easy to remove if you don't want to keep it.
I knew that trick for offroad use but had never seen how to do it with pictures...
Just one thing : if you don't want to take a chance and ruin your carb, you can try the same trick but only push small lengths of rubber hose on the carb fuel vent tubes and on the U-shape copper tube ( just cut the legs shorter ).
No drilling, easy to do, easy to remove if you don't want to keep it.
Last edited by 73StreetRace; Jul 29, 2009 at 09:17 AM.
Thread Starter
Melting Slicks
Joined: May 2007
Posts: 3,246
Likes: 4
From: Bay Area CA
Yes its running quite well. The larger jets and discharge nozzle did make it more responsive. I'm running a pretty mild cam (Comp Cams XE262) so I didn't change the power valve.
I just installed longer vent tubes; I didn't connect them with fuel line. The tubes are about an inch longer than stock; the tops are about a quarter inch under the air cleaner lid. It has cured the stalling issue.
Here's a link to a page that addresses the fuel slosh issue in detail. Offroad tricks for Holley 4 barrel carbs
I just installed longer vent tubes; I didn't connect them with fuel line. The tubes are about an inch longer than stock; the tops are about a quarter inch under the air cleaner lid. It has cured the stalling issue.
Here's a link to a page that addresses the fuel slosh issue in detail. Offroad tricks for Holley 4 barrel carbs
Also, did you replace both discharge nozzles or just the primary?
Last edited by RunningMan373; Jul 29, 2009 at 04:45 PM.
Melting Slicks
Joined: Jun 2003
Posts: 2,802
Likes: 241
From: Niles, MI
Did you make your own longer vent tubes, or buy them from Holley? The discharge nozzle is the small rectangular thing that sits between the venturis held down by the large phillips screw right? You have a source for these?
Also, did you replace both discharge nozzles or just the primary?
Also, did you replace both discharge nozzles or just the primary?
Got the discharge nozzle from either Jegs or Summit; I can't remember. The discharge nozzle is under the choke, circled in red in the pic below. I just replaced the primary nozzle.
