MBHR

Hi all, I am currently running a 2014 E63 S-AMG and getting a custom tune for both 93 and race gas with a handheld unit to switch between both. I had a question about having only 5-gallons of race gas in the tank... With that little amount of fuel in the tank, will it starve the system when I floor it assuming the car is forcing the fuel towards the back of the tank in all or will this be a total non issue. I apologize up front if this seems to be a ridiculous question. Any input on this would be helpful and and greatly appreciated; thanks in advance!!!

PeterUbers

I think the answer is no because there is a high and low pressure fuel pump that compensates for this issue

MBHR

Thanks for your response!!

TECHNICIAN

Yes it can in some instances. Without data logging its hard to say what the limit is. I'd do 10 gallons to be safe probably. Having low and high pressure pumps has no bearing on it. If you starve the low pressure pump the high pressure pump is also starved, which causes misfires and/or a lean condition

MBHR

Thanks so much for your response. Lord knows I do not want to have any issues so I will definitely take your advice and run with 10-gallons to mitigate any potential issues. Many thanks for getting to my post/thread here!

chiromikey

5 gallons is more than enough to prevent any fuel starvation issues. I have enough runs in with less fuel than that to say so definitively.