eclou

I found these Mopar 52# Siemens low-impedance injectors for sale. Less than $40 per. I have read that some others have used these. Whaddaya think?

http://shop.store.yahoo.com/chucker54/injectors.html

They are called the Super 60 +40%. Apparently they were used for the Shelby turbos.

adrial

They're rated as 52lbs/hour @ 55psi (3.8 bar). Aren't most injectors measured as Xlbs/hour @ 43psi (3 bar)?

eclou

Also found interesting intercooler cooling kit. Probably not enough for track usage, but .....

http://www.turboneonstore.com/turbo_fuel.htm

scroll to the bottom

NZ951

N20 kit which they suggest using C2O in???... you can get cheaper cry C2O kits...

cpt_koolbeenz

I have those exact injectors. Danno made me a custom chip for them - they work great...

Danno

"They're rated as 52lbs/hour @ 55psi (3.8 bar). Aren't most injectors measured as Xlbs/hour @ 43psi (3 bar)?"

"I have those exact injectors. Danno made me a custom chip for them - they work great..."

Yeah, those injectors (looks like Siemens) are actually 46 lb/hr @ 43.5psi (3.0 bar) once you scale them to standard specifications . On Chris's chips, I think I actually used 47 lb/hr, but gave him +2.3/4.6/6.9% enrichments with each click on the FQS switch. Should be good for about 270-280rwhp @ 80 %.

eclou

Cool! Custom tuning ala Danno. In my E36M3 madddd tuning days, custom software was made of unobtainium. Had to beg the man himself (Jim Conforti) to even answer an email question. No luck for the OBDII'ers. Now finally he is coming out with a universal programmable module for all OBD I and II.

seb928s

http://www.racetronix.com/Racetronix..._Sale-55s.html

I believe those are true 55# injectors. I heard some people using them. I would want to know if those are plug and play or do we need do something to make them work and not burn up the DME?

Sam Lin

Those need ballast resistors, roughly $10 from Newark Electronics. All info was posted in here a while ago, just search.

Sam

Matt H

Sam, et. al. - There has been debate at length about the resistors. I am 99% sure tha no one ever came up with a failure. That is to say that everyone says you need them except the upscale builders who say it doesnt matter (except under certain conditions and then the resistors wont help, you would need a heat sink and cooling fan). Does ANYONE know of a confirmed failure of the DME caused by running Low-Impedence injectors?
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NZ951

You mean confirmed failure running low impedence without ballasts?

Danno

It's not a black & white issue. If you have a street car that doesn't see much time above 5500rpm and full-throttle, you should be fine. However, if you use your injectors at high duty-cycles, like on the track, the heat will build up in the driver transistor:

David Salama - 1/26/03
Pelican Parts - marksportcts (might be referring to Salama)
Blitz951 - DME and relays getting hot (good tech in this one)


This isn't an all-or-nothing, yes/no kinda thing. You need to use numbers and determine actual current-draws and measure temperature rises in the DME. Then it'll all make sense. Time is also a factor here as well.

BTW - Beab is an EE who does this for a living...

here are some numbers of EFI boxes and their injector driver(s):

Link-1/2: minimum 1.25-ohms per driver, max-current = 10.4 amps
2-injectors parallel (2.5-ohms each) per driver, max-current draw = 13v / (2.5/2) = 10.4 amps
2-injectors parallel (14-ohms each) per driver, max-current draw = 13v / (14/2) = 1.9 amps
4-injectors parallel (14-ohms each) per driver, max-current draw = 13v / (14/4) = 3.7 amps


Electromotive TEC-3: mininum 1.22 ohms per driver, max-current = 10.7 amps
2-injectors parallel (2.5-ohms each) per driver, max-current draw = 13v / (2.5/2) = 10.4 amps
1-injector per driver, max-current draw = 13v /2.5= 5.2 amps

MoTeC: mininum 1.20 ohms per driver, max-current = 10.8 amps
2-injectors parallel (2.5-ohms each) per driver, max-current draw = 13v / (2.5/2) = 10.4 amps
1-injector per driver, max-current draw = 13v /2.5= 5.2 amps

Stock Bosche DME: minimum 1.0 ohms on single driver, max-current =13.0 amps
4-injectors stock parallel (5.5-ohms each), max-current draw = 13v / (5.5/4) = 9.5 amps
4-injectors low-imp. parallel (2.5-ohms/ea), max-current draw = 13v/ (2.5/4) = 20.8 amps

NZ951

Do injectoras have the impedence written on them? How can you find it out?

Matt H

Danno - thanks for that. I just wonder if 3 failures out of ALL the cars here running large injectors without resistors is a large enough sample (if you know what I mean). Still very interesting information. BTW - why doesnt anyone offer a heat seak and fan setup for it, it is after all just a PC board, could the cover be modified for that?
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NZ951

Good point Matt. I would prefer a solution like that, as long as it is relaible. Ambient temps would be a factor, and remember the computers are in a box without ventiliation. Cant have dust getting in there...