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holley fans pls. read

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bikerfox View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote bikerfox Quote  Post ReplyReply Direct Link To This Post Posted: Feb/02/2023 at 3:16pm
Originally posted by ccowx ccowx wrote:

When I ran a cross ram, I also had four corner idle, which will likely help your mixture, particularly at idle. 

chris--two idle mixture screws per carb, not four. it's a 4160 with secondary metering plate.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote ccowx Quote  Post ReplyReply Direct Link To This Post Posted: Feb/02/2023 at 4:20pm
You can do one mixture screw per barrel. Might help, since mixture is always an issue with a Cross ram. 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Sonic Silver Quote  Post ReplyReply Direct Link To This Post Posted: Feb/02/2023 at 5:50pm
Originally posted by bikerfox bikerfox wrote:

Originally posted by Sonic Silver Sonic Silver wrote:

At least, I assume that carburetor has 2 places to hook up vacuum advance. I know there is one right above the mixture screw on the passenger side, close to the front float bowl screw in plug. That should be ported vacuum.

as i said b4, vacuum advance is not hooked up.  i don't have one of these (below) hooked up.
also, the carbs have been balanced with a dvorak machine, which does the same thing
as a vacuum gauge.


I misunderstood when you said "these carbs use mechanical secondaries and there is no vacuum advance hooked up." Lots of carbs use mechanical secondaries and have ports for connecting vacuum advance. If you hadn't mentioned mechanical secondaries, I wouldn't have said anything. I thought you might have vacuum secondaries mixed up with vacuum advance. Sorry. Just trying to help.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Trader Quote  Post ReplyReply Direct Link To This Post Posted: Feb/02/2023 at 6:17pm
Vacuum secondary's would actually work well, but they have to be teed together and use the same vacuum source. Not going to get the same acceleration as mechanical though.
Mechanical secondary's work, but do tend to work better if your tendency is to floor it. Not so good at smooth transition with partially opening.
I'm assuming we dealing with a lead foot here:)
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Post Options Post Options   Thanks (0) Thanks(0)   Quote bikerfox Quote  Post ReplyReply Direct Link To This Post Posted: Feb/02/2023 at 10:28pm
Originally posted by Trader Trader wrote:

I'm assuming we dealing with a lead foot here:)
my foot's so heavy i think it's made of lead!!
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Post Options Post Options   Thanks (0) Thanks(0)   Quote bikerfox Quote  Post ReplyReply Direct Link To This Post Posted: Feb/02/2023 at 10:35pm
so, here's a twist in this issue:

take a look at roadventure's post.  i'm wondering if it will make a
diff. if i do what he did.  currently, i have a pcv in a baffle, located
in the valve cover.  a hose connects it with the back of the two carbs (using "t's").
i could do the same thing by plugging the ports exiting the back of the
carbs and running the pcv valve directly to the air cleaner housings
where they go up inside of the air cleaner elements.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote bikerfox Quote  Post ReplyReply Direct Link To This Post Posted: Feb/02/2023 at 10:37pm
Originally posted by Sonic Silver Sonic Silver wrote:


I misunderstood when you said "these carbs use mechanical secondaries and there is no vacuum advance hooked up." Lots of carbs use mechanical secondaries and have ports for connecting vacuum advance. If you hadn't mentioned mechanical secondaries, I wouldn't have said anything. I thought you might have vacuum secondaries mixed up with vacuum advance. Sorry. Just trying to help.

ss--hey, no harm no foul....i knew we were getting "lost in translation."
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Finis Quote  Post ReplyReply Direct Link To This Post Posted: Feb/16/2023 at 3:16pm
My experience wwith my crossram was revealing. I started with 1850s and always had idle issue. Was warned about idle issues with these. My vacuum at idle was 5 inches 1200 rpm. if it fell below 5 it woud kill. Tried cracking the secondaries, help some, drilled the blades but alway low idle vacuum. Finally ordered a new valley pan gasket and removed the intake. I measured the new pan seal surfaces and compared that to the removed one and discovered the seal surfaces along the top were not crushing. i placed the intake onto the motor and measured with feelers front to back both top and bottom, both sides. Not square and not parallel. next I used my carpenter square and could see the issues. I warned my machinist we would proceed slowly. After two trip the manifold sit evenly on the motor with .002 variacion. The end result was 8 inches of vacuum and 1000 rpm. Steady. I did finally go to Quickfuel 450 cfm vacumm secondarys. far more adjustability.


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Post Options Post Options   Thanks (0) Thanks(0)   Quote Finis Quote  Post ReplyReply Direct Link To This Post Posted: Feb/16/2023 at 3:25pm
Btw, my cam is 255, 266 duration with a 106 lobe separation. This coupled with alot of plenum, I'm happy with this idle.
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