Cascade Crew

Al Hasse · Posted: Tue Jul 19, 2011 7:12 pm Post subject: Injector flow calculation

Since getting information from this builder and his third party vendors, I decided to take my injectors out to have them flow tested. they are a pair of 5235206*ACR as stamped on the top of the injector body, which by my best guess are 61 lb/hr.

When I picked them up today, I looked at the data sheet to find they were tested at 20psi and had a flow rate of 104 (I assume that is lb/hr). For tuning, since I don't have the AFPR yet, nor a pump to support that pressure, how do I find out what the flow is at 13psi?

chevymad · Posted: Tue Jul 19, 2011 7:35 pm Post subject:

Do they have any other data points so you can extrapolate a curve?

Al Hasse · Posted: Tue Jul 19, 2011 7:50 pm Post subject:

Not much of a data sheet. Just flow rates before and after cleaning and pressure setting for testing.

I did find one of RBob's formulas and a couple of other online flow calculators which seem to agree with each other. Seems that if indeed I am at 104 lb/hr @ 20psi, then at 13psi, the new flow rate might be 84 lb/hr.

http://www.csgnetwork.com/fiflowcalc.html

The engine builder said his TBI and carb guy rates the TBI at 700 cfm.

Also, plugging 84 lb/hr @ 13psi into the EBL utility program, those numbers support about 317 HP which is about what Paul Anderson (builder) said the motor could make. I'm still skeptical.

Al Hasse · Posted: Thu Jul 21, 2011 3:52 pm Post subject:

Well, that 104 number is cc per cycle, but I couldn't get how long the cycle was from the machine shop guy on the phone. I'll just go with the stock 5.7L 61lb/hr size and go from there. I can always get larger injectors later, assuming they'll fit the injector pod.

blue89 · Posted: Sun Jul 31, 2011 11:11 am Post subject:

Why would they measure it in cc/cycle? Shouldn't it be cc/min? That would mean you would only have less than 10 lb/hr, which doesn't make sense at all. What did they do? I'd be a little miffed if I payed a company to do this service and they couldn't tell me what units they were measuring.

Al Hasse · Posted: Sun Jul 31, 2011 11:47 am Post subject:

I wasn't really satisfied to hear what the numbers meant and that there wasn't a way for me to convert them to a value I could use.

For now, I'm going with the standard 5.7L 61lb/hr @ 13 psi, the motor idles well with that and will rev smoothly and easily up to 3000 and this will have to do until I get a new fuel pump and adjustable regulator. I've also found a place where I can get the injector pod assembly with a pair of 454 80lb/hr injectors already installed for about $130.