Fuel Pressure dropping while under boost
05-18-2017, 11:08 AM
#22
Probably just a mistake putting the regulator that high but at least it caused him to dump the crap pump and get something that works.
05-19-2017, 02:15 AM
#24
Advanced
Thread Starter
That picture was the first tune. We have set the fuel pressure at 55psi and still having the issue with the pump running lean after it been running a long time. Either way the Walbro 450 still hasn't gone lean after a long time running.
06-03-2017, 01:41 PM
#29
Melting Slicks
06-04-2017, 07:01 AM
#30
Melting Slicks
06-15-2017, 03:29 AM
#31
Drifting
well, i thought i would mention it. post #1 showed a pressure of 72 psi base and 85 psi max. i dont think that is anything extraordinary.
on the topic of "stupid high fp": when the fuel systems used to run 3 bars (or 2.5 bars) i would set up my cars to run at 4- 4.5 bars. the atomisation is better at these levels, keeping in mind that around 6 bars the injectors stopp working. so if you then run say 1.5 bars of boost you end up with 90 psi fp max. its not much different on a referenced ls1. and a pump upgrade yields around 65 psi at idle returnless anyway.
of course you need a pump supporting that and if you dont find one in the walbro catalog, dont despair, there are plenty of unexpensive pumps that will support 6-8 bars. i preferred to use bosch pumps for the ke-jetronic in audis. those systems ran 6 - 6.5 bars stock.
on the topic of "stupid high fp": when the fuel systems used to run 3 bars (or 2.5 bars) i would set up my cars to run at 4- 4.5 bars. the atomisation is better at these levels, keeping in mind that around 6 bars the injectors stopp working. so if you then run say 1.5 bars of boost you end up with 90 psi fp max. its not much different on a referenced ls1. and a pump upgrade yields around 65 psi at idle returnless anyway.
of course you need a pump supporting that and if you dont find one in the walbro catalog, dont despair, there are plenty of unexpensive pumps that will support 6-8 bars. i preferred to use bosch pumps for the ke-jetronic in audis. those systems ran 6 - 6.5 bars stock.
Last edited by romandian; 06-15-2017 at 03:31 AM.
06-15-2017, 03:32 AM
#32
Drifting
well, i thought i would mention it. post #1 showed a pressure of 72 psi base and 85 psi max. i dont think that is anything extraordinary.
on the topic of "stupid high fp": when the fuel systems used to run 3 bars (or 2.5 bars) i would set up my cars to run at 4- 4.5 bars. the atomisation is better at these levels, keeping in mind that around 6 bars the injectors stopp working. so if you then run say 1.5 bars of boost you end up with 90 psi fp max. its not much different on a referenced ls1. and a pump upgrade yields around 65 psi at idle returnless anyway.
of course you need a pump supporting that and if you dont find one in the walbro catalog, dont despair, there are plenty of unexpensive pumps that will support 6-8 bars. i preferred to use bosch pumps for the ke-jetronic in audis. those systems ran 6-6.5 bars stock.
on the topic of "stupid high fp": when the fuel systems used to run 3 bars (or 2.5 bars) i would set up my cars to run at 4- 4.5 bars. the atomisation is better at these levels, keeping in mind that around 6 bars the injectors stopp working. so if you then run say 1.5 bars of boost you end up with 90 psi fp max. its not much different on a referenced ls1. and a pump upgrade yields around 65 psi at idle returnless anyway.
of course you need a pump supporting that and if you dont find one in the walbro catalog, dont despair, there are plenty of unexpensive pumps that will support 6-8 bars. i preferred to use bosch pumps for the ke-jetronic in audis. those systems ran 6-6.5 bars stock.
Last edited by romandian; 06-15-2017 at 08:08 AM.
06-15-2017, 05:06 AM
#33
Melting Slicks
well, i thought i would mention it. post #1 showed a pressure of 72 psi base and 85 psi max. i dont think that is anything extraordinary.
on the topic of "stupid high fp": when the fuel systems used to run 3 bars (or 2.5 bars) i would set up my cars to run at 4- 4.5 bars. the atomisation is better at these levels, keeping in mind that around 6 bars the injectors stopp working. so if you then run say 1.5 bars of boost you end up with 90 psi fp max. its not much different on a referenced ls1. and a pump upgrade yields around 65 psi at idle returnless anyway.
of course you need a pump supporting that and if you dont find one in the walbro catalog, dont despair, there are plenty of unexpensive pumps that will support 6-8 bars. i preferred to use bosch pumps for the ke-jetronic in audis. those systems ran 6 - 6.5 bars stock.
on the topic of "stupid high fp": when the fuel systems used to run 3 bars (or 2.5 bars) i would set up my cars to run at 4- 4.5 bars. the atomisation is better at these levels, keeping in mind that around 6 bars the injectors stopp working. so if you then run say 1.5 bars of boost you end up with 90 psi fp max. its not much different on a referenced ls1. and a pump upgrade yields around 65 psi at idle returnless anyway.
of course you need a pump supporting that and if you dont find one in the walbro catalog, dont despair, there are plenty of unexpensive pumps that will support 6-8 bars. i preferred to use bosch pumps for the ke-jetronic in audis. those systems ran 6 - 6.5 bars stock.
If you were using the Bosch pumps, then that is a different matter, but you were not using those ? And you cannot compare an ancient jetronic system to modern fuel injectors. They're just vastly different.