View Single Post
Old 03-02-2009   #6 (permalink)
RallyBob
Project 1450 supporter...
 
RallyBob's Avatar
 
Join Date: Mar 2002
Location: Pleasant Valley, CT
Posts: 7,449
Real Name: Bob Legere
RallyBob has a spectacular aura aboutRallyBob has a spectacular aura about
Garage
Originally Posted by markandson View Post
Ahh....something else I apparently don't know enough about. I assumed it was a simple system with a pump and an accumulator and a pressure switch to just keep the accumulator at the specified pressure thereby eliminating the need for a return line. I guess it must be more complicated than that.
A bunch of newer cars have returnless systems that are done by the OEM's simply for cost/simplicity. The ECU controls the pump essentially, but there is a cap as to the limitations of these systems. For aftermarket performance upgrades, most folks scrap the returnless system and plumb a 'normal' return-style system.

Example: 350Z Nissans use a returnless system, when turbocharging them the fuel system is often the limiting factor. Plus a return-style system runs cooler...unused fuel in the feed line goes back to the tank, mixes with the remaining fuel, and comes back 'cooled off'.
__________________
My Flickr photos.
Jan. 3, 1984 - Jan. 3, 2009, that's 25 years of this damn Opelitis!
C.R.L. 9/22/69 - 12/8/99, J.M.L. 3/3/43 - 6/15/04
RallyBob is offline   Reply With Quote Top home