FireDemonSiC

In the process of tuning my new engine. Wanted some opinions on this subject.

I have a set of Yellow Bosch design IIIs. The base pulse constant values in my tune are already set a little higher than recommended, the fuel pressure is at 55psi, the VE cells are close to 100 at 90-100kPa and the AFR is still around 14:1 at WOT. I COULD bump the BPC values a bit further but was more curious at a different approach: Maxing out my holley regulator. I believe the maximum range for it is in the neighborhood of 65-70psi.

The thing that pisses me off about the design IIIs is that NO ONE can answer for certain what flow they're rated at.

FIC claims 22lbs. Some sources say they were rated at 19lbs using Ford's pressure of 38. Punch the part number in Google and it says 19lbs at 3bar.

I called Bosch to try and dig up some info straight from the manufacturer and they said that information is "confidential to ford motor company".

FIC claims they flow test them 22lbs at 3bar. I'm honestly not sure who to believe here.

To eliminate any confusion and give myself some headroom, I'm thinking to just crank up the pressure. The design IIIs are supposedly very tolerant to higher pressures.

What are everyone's thoughts? Has anyone ran pressures that high on a TPI setup before? Motor in question is a 10.5:1 aluminum headed 334 (Yes you read that correctly it's a 305 stroker) with forged internals.

I figure if I kill the injectors and end up needing a new set I had that coming anyways. Might as well exhaust my options before spending the money.

southbay08

It's unfortunate but not all information on google and some websites is not accurate when it comes to flow rates on injectors. I understand your frustration because you don't know who or what to believe. Fuel injectors have different flow rates depending on the pressure that you run them at. Yes, at Ford pressure 39psi the yellow bosch lll's are rated at 19lb because that's what they flow at that pressure. At GM pressure 43.5psi they flow 22lb. If you continue to go up on the pressure the flow rate will increase as well. So if you plan on running them at 55psi they will flow about 24lb. You are correct..these injectors are tolerant of high pressures. You not going to "kill" them

FireDemonSiC

Not the injectors I ended up killing after all.

Got about 40 miles of good wideband tuning in yesterday and the fuel pump died as soon as I pulled up at home. At least it waited for an appropriate time lol.