600+ and fuel setup

1slow370

well the heat is a factor but i suspect it's mainly due to the amperage a larger motor consumes, a 255 for instance can draw 2-3 times the amperage the stock pump does, that is why it should be rewired with its own relay and larger guage wiring, 15-18 amps constant is quite a lot of power, then start talking about running two of them and you are looking at over 25 more amps of constant draw the car now has to put up with and this isn't a sound system, we are talking all the time constant draw. My old suzuki swift had a 40amp alternator, it would barely be able to keep up with just those pumps.

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Nissan370

i have my 340lph pump wired to the battery with larger gauge wiring
so i get the return stage 0 kit that should be a good starting point.

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370z vsr motorsports single turbo/built motor 9.1cr 525rwhp/450rwtq @ 10.5psi (stock maf maxed out)

OldBoy

Hahaha, yeah reminds me my '90 Civic Cx base model with the 60 amps alternator, could barely run every electrical accessories at the same time.

I agree it would pull a lot of power from the alternator just to keep up, but really, thats the price to pay to pump more fuel into the engine, there's just no getting around it. Plus, most newer cars have very large alternators to keep up with all the powered accessories.

That being said, I think it would be interesting to use a twin pump setup for high HP engines. I'll elaborate a bit more on what I meant by 2-stage. Imagine having 2 pumps each hooked up on a separate relay. First one could be an OEM sized pump that's on all the time like a regular fuel pump. The second one on the other hand, would be a high output one and could be wired to a relay which would be energized by a fuel pressure sensor on the fuel rails similar to an oil pressure sensor but set for 50 PSI. So essentially, the second and bigger fuel pump would only come on if the pressure was dropping below 50 PSI. This way, when your just cruising around, your not drawing 25+amps all the time and moving massive amounts of fuel heating it up, you'd only pump it when its really needed. Add a little timer on the relay to keep the pump from cycling ON-OFF for nothing and you're good to go.