Question about 50cc carb accellerator pump
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Question about 50cc carb accellerator pump
If I was to go to a 50cc pump would I put one on the primary and secondary or would I just buy 1 an put it on the secondary.
I don't think my pump shot is long or strong enough with the 30cc pumps on my 825 Race Demon for my new 427ci
I don't think my pump shot is long or strong enough with the 30cc pumps on my 825 Race Demon for my new 427ci
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From: Austin Texas
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my very old Holley double pumper, Orginally had a 50cc on the rear only,
it is a spreadbore carb.
Are you stumbling on acceleration ?
it is a spreadbore carb.
Are you stumbling on acceleration ?
Pro
Joined: Jun 2004
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From: Lantana TX
I would look to change the squirters and pump cams first. The Cams will change the ammount of fuel and the rate it is delivered, while the squirters change the ammount only.
The pump should be the last thing you change.
The pump should be the last thing you change.
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The demon is a hard to setup on your own animal. It really needs to be dialed in on a dyno with sniffers
I drilled out the primary squirters .004. It's been awhile so don't quote me on the exact size. But stock is something like .031 and I went to .035
Then just adjust you linkage so the slightest movement make it wet.
It is also wise to replace the rubber pump diaphragm every couple of years
I drilled out the primary squirters .004. It's been awhile so don't quote me on the exact size. But stock is something like .031 and I went to .035
Then just adjust you linkage so the slightest movement make it wet.
It is also wise to replace the rubber pump diaphragm every couple of years
Last edited by gkull; Sep 11, 2008 at 12:55 AM.
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I have a Quick Fuel 950, but I believe your Demon flows similar CFM. Don't be shy with the squirters, I installed #42's front and rear.
The secondaries with the large squirters should overcome the need for a 50cc rear pump.....you'll have to judge by driving. Good Luck
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Anyway not a big deal I new I would have to tune the carb for the bigger motor. Seems like the pump shot might not be long enough or something. Actually at this point it could be any one of many things, I only have about 150 miles on the motor. I just got some bigger squirters ( I know a smaller squirter will give a longer pump shot
) today and I am going to try a few other things before going to the 50cc pump
