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Rick MacLaren · Guest

I'm going to put in bigger injectors into my car next week, and/or clean out the ones I've got.

Which ones are a straight swap into the 931? is there one that exists that is a straight swap? And if so, will I need a fuel rail?

Peter_in_AU · Joined: 29 Jul 2001 Posts: 2743 Location: Sydney, Australia

fuel rail? Have you converted to EFI?

Rick MacLaren · Guest

Not yet. That's part of the project though. Here's what I'd like to make, though I probably can't do as good a job!

See Alex's site: http://www.alexroy.net/FuelRail.html

A 928 fuel distribution, 8:1, unit would be a nice.

I like working with metals and if it's already been done, well, why revinvent the wheel? I think the guy should make 'em and sell 'em, personally. :smile:

[ This Message was edited by: Rick MacLaren on 2002-10-13 03:01 ]

Peter_in_AU · Joined: 29 Jul 2001 Posts: 2743 Location: Sydney, Australia

I have been told that the fuel rail from a Dodge 2.2 Turbo has the right injector offsets. I can't confirm it myself. There's a pic of one about half way down this page http://www.lucasviking.com/shelby/articles/mtsissu4/mtsissu4.htm

Alternatively you could make your own. Have a look at http://www.sdsefi.com/techrail.htm for some info.

Here's a link on injector flows http://www.autospeed.com/A_0102/P_1/article.html if you're going to build a rail then get at least one injector first so you get the injector to fuel rail mount correct.

[ This Message was edited by: Peter_in_AU on 2002-10-13 08:57 ]

Rick MacLaren · Guest

I checked those out Peter. They're very informative! I can use that information.

A lot of this is just pure learning - there's no 'right' setup.

I'd like if the Dodge ones put out more than our own and required no modification. I'll be checking into it.

"if you're going to build a rail then get at least one injector first so you get the injector to fuel rail mount correct." Agreed.

[ This Message was edited by: Rick MacLaren on 2002-10-13 14:38 ]

John H · Guest

I wouldn't bother changing the injectors - either put new ones in or have the old ones checked for flow rates and spread etc.
The injectors and fuel unit will flow enough gas for up to at least 260hp, so unless you are going to runover 1.1/1.2 bar boost no need to incur additional expense for nothing.

Dave Ewing sent me a 2.2 Dodge fuel rail and it is the same spacing as the 931. to use this you really need to go over to EFI and Dave is using injectors out of a Mercedes 450 suitable turned down to fit the Porsche pocket.

Rick MacLaren · Guest

I had no idea they put out that much!

924RACR · Posted: Tue Oct 15, 2002 10:27 pm Post subject:

Shouldn't be that hard to check with the turbo Dodge boys and finger out what injectors they're using for high-boost applications... plenty of those types here in Motown... the only thing is thos guys are all a little nutty, like a few days past the end of a prescription and no time to get to the doctor (shrink), know what I mean?

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Peter_in_AU · Joined: 29 Jul 2001 Posts: 2743 Location: Sydney, Australia

shit! those injectors are HUGE!

Found them at http://www.mopartsracing.com/parts/fuel.html under "super 60 + 40% injectors" about 2/3 down the page. They rate them at 55lbs/hour which is right off the flow scale at http://www.autospeed.com/A_0102/P_1/article.html

The 951 injectors are rated at 29lbs/hour.

Rick MacLaren · Guest

So the choice really is: Does a person want to go beyond 260 HP, and if so, it necessarily means injectors, EFI and a brain box.

924 turbo · Guest

There's always the option of supplemental fuel controllers as well. Look at the Haltech F5, or the HKS AIC. They add one or two (or more) EFI injectors and control them based on RPM and vacuum/boost. You'd have to make something custom to hold them, though.

Rick MacLaren · Guest

Do the IMPEDENCE match on these 55 lb ones with ours on the 931? Researching now, but if anyone has info on this it'd help...

924 turbo · Guest

Rick MacLaren · Guest

Jon, you said "Impedance is an electrical measurement." I'm writing that down now so I can remember it. I'll even repeat it silently to myself at work for a while.

No shit. Did you wake up this morning and just blurt that out before you ate your Wheetabix?

Man! Here I was, dumb as a stroke patient, thinking "impedence...man, I don't know that that is...so I think I'll just toss that into a conversation somewhere."

What's your point Jon? Can you clarify? Or are you having a Touretts moment?

lol

[ This Message was edited by: Rick MacLaren on 2002-10-16 02:08 ]

924 turbo · Guest

I liked what you wrote before better, Rick. The part about the walking into telephone poles, etc. You know, the offensive stuff.

The 931 uses mechanical fuel injection. There is no electronic metering of the fuel at the fuel injector itself. Thus, the 931 fuel injectors have no electronic circuits. And thus, no impedence.

Getting the picture now?