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spuggy spuggy is offline
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Join Date: Jul 2003
Location: Glorious Pac NW
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Quote:
Originally posted by iamchappy
Henry at Supertec said all I would need is one 44 to do the job


Cool, that's pretty much what I had believed from the spec sheet, but good to get it confirmed!

Quote:
but having the extra pump laying around I thought maybe I could put it to good use if 2 works better than one.
What is the purpose of using two?
Most inline pumps will make a considerably higher flow rate if supplied by another pump, rather than simply gravity fed. It can also maintain that flow rate at a higher pressure.

The effect of operating at a higher pressure (like in a CIS system) is to effectively decrease the maximum flow rate of the pump. Also, the harder you work the pump, the more current it draws.

Using two pumps allows bigger flow rates at higher pressure.

Despite some conservative specifications for the 044, (Bosch quote it as 200LP/H on the Motorsport reference sheet, about 35LP/H more than they quote the stock pump), Jay Racing had some flow charts that compared it to the Walpro "255" pump and showed it flowing much, much more fuel. Like 60+% more fuel, especially at the high end.

They seem to have just re-organized their web site, and that chart isn't there anymore, but there's still some useful info here.
http://www.jayracing.com/index.php?main_page=product_info&cPath=2_5&products_id=1

There's some good Bosch cross-reference information and specs in these links:

http://apps.bosch.com.au/motorsport/downloads/fuelpumps.pdf
http://apps.bosch.com.au/products/saa/efi_crossref.pdf
http://apps.bosch.com.au/products/saa/efi_techserviceparts.pdf

There's even vehicle-by-vehicle application sheets here, just the thing for digging around breaker's yards:

http://apps.bosch.com.au/products/saa/efi_vehicleapplications.pdf

If you were going to use two pumps, I'd be inclined to put the 044 last, or use two 044's. But you should remember that I have no expertise here, and this is just my gut feeling...

Excess capacity only means the pumps aren't worked as hard, and the fuel is pumped around faster - thus kept cooler. It's all good.

Cheers,

Andy
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'77 S with '78 930 power and a few other things.
Old 03-19-2007, 03:09 AM
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