Re: Electric fuel pump
Posted: Tue Jan 05, 2021 10:51 am
I had problems with the engine misfiring at the end of long straights when at full throttle and maximum revs and maximum power for a significant period. Dyno work and use of a similar pressure gauge attachment showed it was due to the Facet low pressure cylindrical pump and standard fuel line failing to delivery the volume at enough pressure to match the well developed engines consumption after its most recent changes a few years ago when I went from Avgas to unleaded pump fuel due to a regulation change for my class. Probably not a problem on a less developed engine but another data point if you're pushing the top end of twin cam power
Based on my Dyno guys recommendation ( he really knows his Weber's). He demonstrated the change during the dyno runs by hooking up his fuel supply trolley using his recommended set up to replace mine as he comes across this issue often. Based on this I installed a new larger fuel line and a Carter 4389 fuel pump with 6 psi output and a Malpassi "petrol king" regulator to control the pressure at the Carbs to the 2.5 to 3 PSI target at all flows. Probably overkill but all the problems went away once this was done
Carter P 4389 pump - long link but you can find it on Amazon
https://www.amazon.com.au/Carter-P4389- ... XAMW3Y79Y9
Malpassi petrol king regulator - again a long link but you will find on Ebay
https://www.ebay.com.au/i/402556886567? ... 2abd7b8a46
photos of my installation below
cheers
Rohan
Based on my Dyno guys recommendation ( he really knows his Weber's). He demonstrated the change during the dyno runs by hooking up his fuel supply trolley using his recommended set up to replace mine as he comes across this issue often. Based on this I installed a new larger fuel line and a Carter 4389 fuel pump with 6 psi output and a Malpassi "petrol king" regulator to control the pressure at the Carbs to the 2.5 to 3 PSI target at all flows. Probably overkill but all the problems went away once this was done
Carter P 4389 pump - long link but you can find it on Amazon
https://www.amazon.com.au/Carter-P4389- ... XAMW3Y79Y9
Malpassi petrol king regulator - again a long link but you will find on Ebay
https://www.ebay.com.au/i/402556886567? ... 2abd7b8a46
photos of my installation below
cheers
Rohan