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Venturi Jet Pump upgrade

Murray_Calavera
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Ben C34 Grand Master

Ben C34

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Posted

It can happen on some cars that the venturi is too small and means you can't set fuel pressure as low as you want when using a larger intake pump. If you are running a surge tank it wouldn't matter.

 

If you want to you can measure the pressure in the return line, but really if you don't think you have a problem, you don't have a problem!

Murray_Calavera Mentor

Murray_Calavera

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I had a problem the other day, ran out of fuel with half a tank remaining lol. When I filled the tank it took 28 litres so 100% not a gauge issue. 

Random googling of my issue lead me to reading about these upgraded venturis. 

I don't think this is related to my issue, I was just curious what peoples experience was with upgrading the venturi. I had never even heard of them before, then reading the Radium marketing, they make it sound like everyone with an upgraded pump would need one... but if that was the case, surely I would have heard people talking about them before lol. 

Back to my problem though, I'll throw a borescope in my fuel tank when I get some time and confirm that the pump and its sock are exactly where they should be before I start chasing rabbits down random holes. 

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joshuaho96 Veteran

joshuaho96

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Posted (edited)
On 4/18/2022 at 6:18 AM, Murray_Calavera said:

I had a problem the other day, ran out of fuel with half a tank remaining lol. When I filled the tank it took 28 litres so 100% not a gauge issue. 

Random googling of my issue lead me to reading about these upgraded venturis. 

I don't think this is related to my issue, I was just curious what peoples experience was with upgrading the venturi. I had never even heard of them before, then reading the Radium marketing, they make it sound like everyone with an upgraded pump would need one... but if that was the case, surely I would have heard people talking about them before lol. 

Back to my problem though, I'll throw a borescope in my fuel tank when I get some time and confirm that the pump and its sock are exactly where they should be before I start chasing rabbits down random holes. 

I haven't really heard of these venturis being replaced very often in most R33s. For a 450 lph pump it may be necessary but with the 276 lph drop-in pumps it's probably not. From what I see online people don't report issues like this on the R33: https://www.skylineowners.com/threads/help-identifying-this-part.317169/

Edited by joshuaho96

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