 Fuel pressure twin carbs |
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| JFG |
 Jun 15 2016, 02:41 PM
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#1
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Senior Member  Group: Members Posts: 686 Joined: 7-April 16 From: Wales Member No.: 19,869 Region Association: None  |
I have a 1.7engine and will be running twin Weber 40idf's.
My car was originally a 2.0i but came minus engine and ancillaries. The only thing I have is the original 3 port pump. I haven't tested it yet but I won't be running a return so can't use the pumpin this instance. What kind of pressure should I be running the carbs at? Research and past experience (albeit not with 40's) would suggest something in the range of 2.5 to 3.5 psi. Anyone with this set up have any input/advice on pump and flow pressure? |
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| brant |
Jun 15 2016, 02:51 PM
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#2
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914 Wizard Group: Members Posts: 12,167 Joined: 30-December 02 From: Colorado Member No.: 47 Region Association: Rocky Mountains 
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Your experienced numbers are still good.
But I always recommend a return on carbs also |
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| 74ravenna |
Jun 16 2016, 03:30 AM
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#3
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Member Group: Members Posts: 479 Joined: 19-October 14 From: nh Member No.: 18,032 Region Association: North East States
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QUOTE(brant @ Jun 15 2016, 04:51 PM)  Your experienced numbers are still good. But I always recommend a return on carbs also I just installed the fuel pump for carbs that i purchased from CFR but i hadn't planned on running a return. Why are you in favor of doing so? Thanks Steve |
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| SirAndy |
Jun 16 2016, 11:09 AM
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#4
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Resident German Group: Admin Posts: 42,469 Joined: 21-January 03 From: Oakland, Kalifornia Member No.: 179 Region Association: Northern California |
QUOTE(74ravenna @ Jun 16 2016, 02:30 AM) I just installed the fuel pump for carbs that i purchased from CFR but i hadn't planned on running a return. Why are you in favor of doing so? Keeps the fuel cooler and helps prevent vapor lock from boiling fuel in the lines and float bowls. (IMG:style_emoticons/default/smile.gif) |
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| 914Mike |
 Jun 17 2016, 09:52 PM
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#5
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Member Group: Members Posts: 330 Joined: 27-January 03 From: San Jose, CA Member No.: 198 |
QUOTE(SirAndy @ Jun 16 2016, 09:09 AM) QUOTE(74ravenna @ Jun 16 2016, 02:30 AM) I just installed the fuel pump for carbs that i purchased from CFR but i hadn't planned on running a return. Why are you in favor of doing so? Keeps the fuel cooler and helps prevent vapor lock from boiling fuel in the lines and float bowls. (IMG:style_emoticons/default/smile.gif) I had to add two spacers under the manifolds to keep the fuel from boiling in my 2056 with baby Webers. I seem to remember a pressure regulator with a return, but could be wrong about that. Any thoughts on leaving the FI pump under the tank when trying out some carbs? I want to just add the facet pump in the stock location, maybe run a switch to the FI pump to use for priming the system. I'm just not sure if I can pull fuel through the FI pump when it's not running, or if irt would hurt the pump. |
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| SirAndy |
Jun 17 2016, 09:59 PM
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#6
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Resident German Group: Admin Posts: 42,469 Joined: 21-January 03 From: Oakland, Kalifornia Member No.: 179 Region Association: Northern California |
QUOTE(914Mike @ Jun 17 2016, 08:52 PM) Any thoughts on leaving the FI pump under the tank when trying out some carbs? I want to just add the facet pump in the stock location, maybe run a switch to the FI pump to use for priming the system. Plenty of thoughts on both and them thoughts are not positive ... (IMG:style_emoticons/default/biggrin.gif) - Don't use the FI pump for carbs! It's a high pressure pump and trying to use it is asking for all sorts of trouble, most notably a burnt out 914! - Don't use a facet pump! They're noisy and most importantly, they're crap. Use a rotary pump instead. Get one that puts out the correct pressure for your carbs so you don't need to run a pressure regulator. And yes, the FI spacers under carb manifolds helps with keeping the carbs cooler, which is always a good thing. (IMG:style_emoticons/default/smile.gif) |
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Posts in this topic
JFG Fuel pressure twin carbs Jun 15 2016, 02:41 PM
rhodyguy Find a low pressure, self regulated, 2 port pump a... Jun 15 2016, 02:50 PM
SirAndy But I always recommend a return on carbs also
:a... Jun 15 2016, 02:55 PM brant
Plenty of thoughts on both and them thoughts are ... Jun 17 2016, 10:15 PM
914Mike
Any thoughts on leaving the FI pump under the tan... Jun 20 2016, 09:07 AM SirAndy I used this one on my 2056:
http://www.cbperforman... Jun 15 2016, 02:54 PM North Coast Jim
I used this one on my 2056:
http://www.cbperforma... Jun 15 2016, 03:01 PM SirAndy Do you have pics of your installation. I am going ... Jun 15 2016, 03:22 PM MarkV I used the factory wires but the previous owner cu... Jun 15 2016, 03:31 PM JFG I've ordered one of the above mentioned pumps ... Jun 16 2016, 02:15 AM Tbrown4x4
I've ordered one of the above mentioned pumps... Jun 16 2016, 07:25 AM Elliot Cannon I've been using this setup for 13 years now. ... Jun 17 2016, 11:06 PM rhodyguy With the facet and regulator you should still add ... Jun 20 2016, 10:05 AM |
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