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MAF and injector size for homebrew using hybrid turbos

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Old 03-01-2006, 03:18 PM
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Yep, it's easy to get it running and safe, very hard to get it perfectly smooth in every situation
Old 03-01-2006, 03:20 PM
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With what squirters? I'd do a 90 if you're going to run high boost.
Old 03-01-2006, 03:20 PM
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As good as stock as long as you keep your foot out of it.
Old 03-01-2006, 03:30 PM
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Well, RS4's at 5bar with a 90/ RS4 airbox top and accordion and a walbro fuel pump would be nice.
Old 03-01-2006, 03:30 PM
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Default @ the moment

568cc/min - 42lb Greentops w/5bar 63% larger than stock
90mm maf= 45*45*3.1416= 6361.74= 52% larger than stock


Any problems with 90mm @ idle and misfire?
Old 03-01-2006, 03:33 PM
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That'll work. That's the same setup that we put in Uli's car. He's at -11pri now, no codes.
Old 03-01-2006, 03:38 PM
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If you're going the 5bar route plan for a walbro.
Old 03-01-2006, 03:41 PM
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Default Re: That'll work. That's the same setup that we put in Uli's car. He's at -11pri now, no codes.

568cc/min - 42lb Greentops w/5bar 63% larger than stock

Using Fuel Injector Flow Calculator

Enter Original Fuel Pressure 43.5 (is this stock fuel pressure 43.5?)
Enter New Fuel Pressure 72
Enter Rating Of Fuel Injector (lb/hr) 42

New Flow Rate Of Fuel Injector 54 lb/hr
567 cc/min


Isn't this a bit crazy, to be pushing an injector that was rated @ 42lb @54lb ?

Edy
Old 03-01-2006, 03:42 PM
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4 sure,
Old 03-01-2006, 03:44 PM
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Default Nope, fine. Those injectors (and most Bosch squirters) are rated @ 5bar, but the delphi's are not.

It'll be hell on the stock fuel pump though: It has to flow more volume at a greater pressure.


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