evan9381 Posted January 5, 2005 Report Share Posted January 5, 2005 i recently picked up some mustang cobra injectors for a turbo project...they are rated at 42 lb/hr, which i figured up to be around 440cc...what i need to find out is at what fuel pressure do these run the 42 lb/hr? Quote Link to comment Share on other sites More sharing options...
Mensan Posted January 5, 2005 Report Share Posted January 5, 2005 Most cobra injectors are 24s. What year cobra was it? Quote Link to comment Share on other sites More sharing options...
recklessOP Posted January 6, 2005 Report Share Posted January 6, 2005 i don't think any cobra (03 included) came with injectors that big. aren't the lightning injectors 42 lb/hr..? Quote Link to comment Share on other sites More sharing options...
evan9381 Posted January 6, 2005 Author Report Share Posted January 6, 2005 the ebay auction said "mustang cobra injectors...42 lb/hr" maybe its an upgrade from stock injectors? i just need to know at what pressure they flow that rate...ill try to find the box, but i know they came in a "ford racing" box Quote Link to comment Share on other sites More sharing options...
evan9381 Posted January 6, 2005 Author Report Share Posted January 6, 2005 http://i10.ebayimg.com/02/i/02/c5/8d/bb_1_b.JPG description : This sale is for a brand new set of 8 Ford Racing 42lb/hr fuel injectors. They can be used in Ford engines as well as other applications including GM. I will pay the freight in U.S. Quote Link to comment Share on other sites More sharing options...
Guest doggunracing Posted January 6, 2005 Report Share Posted January 6, 2005 Most injectors are rated at 3 bar (43.5 psi), which should be your base fuel pressure. Quote Link to comment Share on other sites More sharing options...
stolen 5.0 Posted January 6, 2005 Report Share Posted January 6, 2005 41-42 psi is about what the mustang runs stock in fuel pressure Quote Link to comment Share on other sites More sharing options...
Nitrousbird Posted January 6, 2005 Report Share Posted January 6, 2005 Ford rates their injectors on a different pressure than the standard 43.5psi, which is why an SVO injector actually flows more than it is rated for (so when programming a non-Ford, you can't just put in 30# for a 30# SVO injector, it's something like 32.3 IIRC). BTW, those aren't considered "Cobra" injectors, just SVO injectors. Quote Link to comment Share on other sites More sharing options...
rl Posted January 6, 2005 Report Share Posted January 6, 2005 Ford rates at 39.5psi, because industry standards just arent good enough. Quote Link to comment Share on other sites More sharing options...
Mensan Posted January 6, 2005 Report Share Posted January 6, 2005 Those are indeed 42s. That is the same injector I run on my car, and 42 is the pressure at which they are rated. Quote Link to comment Share on other sites More sharing options...
evan9381 Posted January 6, 2005 Author Report Share Posted January 6, 2005 hmm...anyone know where i can get these tested? i need a balpark figure, so i can tell the company what CC to set up the ECU for...as it is, they set it up for 400cc, but if i need it for 500cc (give or take) it would make finer tuning w/ the safc a little bit easier Quote Link to comment Share on other sites More sharing options...
Trouble Maker Posted January 6, 2005 Report Share Posted January 6, 2005 Just send them somewhere to get them cleaned and flow balanced. The company will (should) give you a sheet detailing what each injector flowed at before and after. It's probably not a bad thing to do either, especially if they are used. CC/HR=10.5*lb/hr So if they are indeed 42 lb/hr injectors, they are 440cc injectors. But if you are assuming 43.5psi, a 42lb injector rated at 39.5psi would a 44.1lb injector at 43.5psi, which would be 463cc at 43.5psi. You can make an injector flow whatever you want it to as long as it will withstand the pressure (and flow well at that pressure) and your fuel pump will flow what you need it to at that pressure. Here is a website with some good calculators. The fuel pressure, and flow conversion are the ones pertinent to this conversation. I'm interested in what you are putting these on (is it the Hyundai?), care to indulge? Edited back for 43.5psi. [ 07. January 2005, 08:42 AM: Message edited by: Neo ] Quote Link to comment Share on other sites More sharing options...
rl Posted January 6, 2005 Report Share Posted January 6, 2005 Originally posted by Mensan: and 42 is the pressure at which they are rated. No, they are rated at 39.5psi. Ford rates all of their injectors at 39.5psi, not 42. The rest of the industry (for the most part) uses 42.5psi. They are a 42# injector @ 39.5psi pressure drop. EDIT: The new narrow injectors might be rated at 42.5psi, however ford still uses a 39.5psi pressure drop in their system. [ 06. January 2005, 04:16 PM: Message edited by: rl ] Quote Link to comment Share on other sites More sharing options...
evan9381 Posted January 6, 2005 Author Report Share Posted January 6, 2005 ok...so since my cars fuel pressure is @ 50psi, these are gonna flow at over 500cc...damn...this car is gonna be a hell of a sleeper Quote Link to comment Share on other sites More sharing options...
Guest doggunracing Posted January 6, 2005 Report Share Posted January 6, 2005 Originally posted by rl: The rest of the industry (for the most part) uses 42.5psi.It's 43.5 psi, 3 bar. 14.5 * 3 = 43.5. Quote Link to comment Share on other sites More sharing options...
Mensan Posted January 6, 2005 Report Share Posted January 6, 2005 Originally posted by rl: No, they are rated at 39.5psi. Ford rates all of their injectors at 39.5psi, not 42. The rest of the industry (for the most part) uses 42.5psi. They are a 42# injector @ 39.5psi pressure drop. EDIT: The new narrow injectors might be rated at 42.5psi, however ford still uses a 39.5psi pressure drop in their system. You would know better than I would. I concede. Quote Link to comment Share on other sites More sharing options...
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