I posted on another forum trying to get dyno numbers on anyone who had a cam like mine. Naturally it leads to other discussions but someone with close to the identical set up as mine said he was running a fuel pressure regulator. I think he said he has an aftermarket fuel pump. I have two fuel pumps. One is a backup aftermarket that I can manually switch on if the main pump fails. The pump that is working all the time is an SU with solid state guts instead of points.
Is there any reason to have a fuel pressure regulator on this setup? I updated my link with all the dyno info to include AFR numbers and it shows fuel pressure I believe.
http://www.hipnoticinc.com/dyno/
Any reason to have a fuel pressure reg with an SU pump?
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max71
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Steve Simmons
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Re: Any reason to have a fuel pressure reg with an SU pump?
Not on your car, no. You shouldn't have any fuel pressure requirements outside the normal specifications. So long as the stock SU pump is there then you should be good to go. Pressure should be between 2-4 PSI. Factory spec is 2.7 PSI for low pressure and 3.8 PSI for high pressure. HS4 carbs typically use the 2.7 version IIRC.max71 wrote:Is there any reason to have a fuel pressure regulator on this setup?
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malcolmr18zoy
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Re: Any reason to have a fuel pressure reg with an SU pump?
You should probably check the pressure rating of the back up pump, and, if it's higher than 3.5 psi, change it for one within specs. If you run a pump with a higher pressure rating, you will probably over fuel due to flooding. The stock float valves are good up to about 4psi, I'm not sure about the grose jets.
Malcolm
Malcolm
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max71
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Re: Any reason to have a fuel pressure reg with an SU pump?
Thanks Malcolm. Its would suck if my emergency back up pump created another emergency when I used it.
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Jimmy
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Re: Any reason to have a fuel pressure reg with an SU pump?
Well, there's your problem!!
Replace those newfangled electronic guts with old fashioned points and all your problems will be solved, including your friends' and familys', especially if you send this to 20 people within one hour.
Points would NEVER create too much pressure in your fuel system, which could lead to running out of fuel at over 4,500 rpm, right?
Or is that 5,000 rpm?
Replace those newfangled electronic guts with old fashioned points and all your problems will be solved, including your friends' and familys', especially if you send this to 20 people within one hour.
Points would NEVER create too much pressure in your fuel system, which could lead to running out of fuel at over 4,500 rpm, right?
Or is that 5,000 rpm?
In baseball, running into someone is apparently a "collision".
But doing the same thing in a car somehow makes it an "accident".
But doing the same thing in a car somehow makes it an "accident".
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max71
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Re: Any reason to have a fuel pressure reg with an SU pump?
Jimmy I never know how to respond to your threads. Keep dry.