Flow test - are these really 60# injectors?

[TheFleshRocket]

I picked up some used Deatchworks 60 lb injectors. They came in a Deatchworks box but without the flow sheet. I called Deatchworks and they have numbers etched into the bodies which the tech said meant they were Deatchworks sourced injectors, but couldn’t confirm their rating aside from the box indicating that they were 60 lb injectors.

So I hooked them up to my injector tester with a stock 39 lb injector for comparison. I figured since the 60 lb is 50% higher rated than the 39 lb, it should flow 50% more. But the results show that it’s more like a 12-15% difference. In the pic below, the two outer injectors are 60 lb; the two inners are 39. The 60s hit 100ml and the 39s hit upper 80s.

Do these results make sense, or is something amiss?

 

[01yellercobra]

According to that FoMoCo PN right there you have 47lb/hr injectors. Which would coincide with your findings on the flow numbers.

 

[TheFleshRocket]

Ahh, okay.. yeah the B556V part number does come back as 47# injectors. Thanks for pointing that out.

I figured maybe Deatchwerks was just modifying stock Ford injectors so I went poking around on their website and found the flow characteristics for their 39# and 60# injectors under "Tuning Data - General Characterization Summaries".

39# - Matched set of 8 injectors 39lb/hr
60# - Matched set of 6 injectors 60 lb/hr

Sure enough, at 2.0ms pulse width, the 39# is rated at 0.0080 cc per shot, whereas the 60# is rated at 0.0123 cc per shot, approximately 50% more. So if these really were 60# injectors, when they've flowed 100ml on my test bench, the 39# units should have flowed approximately 66ml. That's definitely not even close to what's happening.

 

[MalcolmV8]

Also take note of the pressure at which the injectors are rated and convert accordingly. If brand A rated their 39 lb injectors using 39 PSI and brand B rated their 60 lb injectors at 43 PSI or 50 PSI etc. then you need to do the math to make sure you're comparing apples to apples. Perhaps you already looked into that.

Thanks
Malcolm

 

[MG0h3]

Also take note of the pressure at which the injectors are rated and convert accordingly. If brand A rated their 39 lb injectors using 39 PSI and brand B rated their 60 lb injectors at 43 PSI or 50 PSI etc. then you need to do the math to make sure you're comparing apples to apples. Perhaps you already looked into that.

Thanks
Malcolm

He’s alive!


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[MalcolmV8]

He’s alive!


Sent from my iPhone using the svtperformance.com mobile app

Lol