yea.... more heat... more draw. but i think one small pump mounted outside of the basket could get fuel from the basket and feed just the jets. something that doesn't draw a lot of current and flows high volume. it will not have any head pressure so it should run effortlessly.

 

Not sure how well the regulator would survive sitting in fuel.. never tried it.

should have made the basket bigger.. slap a 3rd low pressure pump in there just to handle the siphon pumps maybe. This is the direction I am tempted to say is the best. dedicate the 2 pumps to fueling the motor. or maybe tap a small fitting into the side of the bottom of the basket.. let the dedicated siphon jet pump draw from there?

I know I saw an add for a siphon pump designed for race apps. But still, no way getting around using fuel to not fuel the engine... no matter how good it is.

 

Looks like we all posted at the same time.

I am thinking of slapping a low pressure "inline" pump in there. Tap a feed line for it into the bottom of the basket, run a line from that to a filter, then filter to pump, other end of pump feeds Y block for siphon pumps.. problem solved.

 

I think originally SRM had shown a 3 pump setup for the 997TT? This could have worked using 1 as a jet only pump. I think SRM now offers a 2 pump setup with 700 LPH pumps? This would be enough pump for 1200 HP on E85 if the correct restrictor size is determined.

 

The 2 crazy pumps solution isn't ready yet...

 

With how deep the fuel tank sumps are...why bother with all that just to have jet pumps grab from the sumps to fill the basket? Has anyone seen how small the actual orifice is on the jet pump itself? Pretty small IMO to fill the basket for two huge 450lph pumps. Seems crazy to me, but what do I know.

 

still lots of slushing around going on in there on acceleration and can aerate the fuel system. also you always have to run two pumps vs right now we run 1 and stage the 2nd one when needed.

 

One pump is on all the time right? im thinking about going with more restriction for now, but doing the 3rd pump method when I pull the motor and upgrade lines/rails

What is the status of yours mark?

 

There is no "primary pump". When you have over I believe 16 gallons, pump 2 is primary, and below 16 gallons in the tank pump 1 is primary. This is why I ran both jet pumps off of pump 1, when pump 2 is the primary they fuel level is well above the top of the surge tank anyway. This also leaves pump 2 at 100% efficiency when it's needed under full throttle. (It's more likely to have less than 16 gallons in the tank).

 

AH. I had ASSumed that the car ran on one pump until a certain mass flow rate (or etc) and then the second pump came on to supply the needed fuel volume

 

Looks like team Garth/Mark/UC solved it with some time on the dyno today with the right size restrictor.

Waiting for my updated parts.

 

Prodigymb -

Valid points. Those sumps are pretty significant though. With a 1/4 tank fuel (remember the float sits up on top of the saddle itself to read fuel level) I don't think there would be any issue. One way to validate though and that's to test it. I'll actually be staging my pumps with this method. I'll monitor fuel pressure logs to see what affect this method has on fuel pressure and if there are any issues doing it this way. Fingers crossed.

Jordon - Awesome man!!! When you say restrictor what are you referring to in the jet pump? What does it look like?

 

.064 nitrous jet

 

what he said ^^^^

 

Will using a nitrous jet as a restrictor make my car faster? I don't want the floor boards to shake off.