FiTech Dual Quad

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Just ran a 492 inch big block Mopar on the dyno today with a CH28 intake and dual FiTech throttle bodies. It made 540 hp and 600 ft lbs of torque with a mild hyd roller cam. Pump gas cruiser engine that is going into an early B body car. Should be a very nice street ride with enough power to get it moving if the owner wants to put his foot into it.
 
I have the corvette filter/regulator, which is supposed to be 58 psi, fitech 40019 in tank pump, new tanksinc tank. Per fitech I left the regulators hooked to vacuum, even though there are no returns at the throttle bodies, and removed the regulator from the pump.

I didn't have a fuel pressure gauge initially so recently I mounted one on an inlet port on one of the throttle bodies.

It shows 40 psi when I prime it, idles at 24 psi, and shows 28 psi with some throttle, then back down to 24 when driving.

I just changed the filter to a wix, and put another gauge in the same location, no change in psi.

The placement of the gauge can't be an issue, right?

Gauge can't be indexed, but that shouldn't matter.

Is the psi supposed to be at 58 when primed, at idle, at full throttle, etc?

I have a feeling this has plagued me for a while, maybe since the beginning.

20181217_162929.jpg
 
If your gauge is accurate- and I'd verify that first, then the regulator is bad or the pump is. The vacuum line will typically drop the line pressure by 10 psi. I would dead head the pump to verify it's putting out the rated pressure. You can measure the pressure directly out of the pump-anywhere before the regulator, or block the return line out of the regulator. If the pump is supplying the proper pressure, then the problem is in the regulator. If the pressure is low, check for power AND ground AT THE PUMP. If the voltage is good the pump is bad. HTH, Steve
 
As far as I know the FiTech system is E85 ready and should adjust itself for it. Luckily none of the stations around where I live (Butler PA near Pittsburgh) carrty it. I realize the it's cheaper but you get less performance out of it as well.
you`ll also burn twice as much 1
 
I have the corvette filter/regulator, which is supposed to be 58 psi, fitech 40019 in tank pump, new tanksinc tank. Per fitech I left the regulators hooked to vacuum, even though there are no returns at the throttle bodies, and removed the regulator from the pump.

I didn't have a fuel pressure gauge initially so recently I mounted one on an inlet port on one of the throttle bodies.

It shows 40 psi when I prime it, idles at 24 psi, and shows 28 psi with some throttle, then back down to 24 when driving.

I just changed the filter to a wix, and put another gauge in the same location, no change in psi.

The placement of the gauge can't be an issue, right?

Gauge can't be indexed, but that shouldn't matter.

Is the psi supposed to be at 58 when primed, at idle, at full throttle, etc?

I have a feeling this has plagued me for a while, maybe since the beginning.

View attachment 1715263151
I don't have fi tech, but have an 8 injector 1200 cfm throttle body, fast 2.0.
I noticed u saying earlier that u wanted to have some exhaust leaks welded up. An exhaust leak WILL screw with ur fuel inj. , no matter what brand. I know a young guy here that has a 340 (probably a stroker) that has a 2-4 barrel fuel inj. on it, it runs n mid tens, and their still tuning it. his runs like a top !
 
Called FiTech today, the 1 year warranty is up tomorrow, they sent me an email with info to fill out so I can get this replaced. I had to send in proof of purchase.
I told them it's too cold to remove a gas tank right now, he assured me I have time, months, to get this done.
He said "we're the little guy too, just like you, and we will make this right."
Good to hear. Got an immediate confirm email right back, not auto generated.
I'll take the gauge off the throttle body and put it right on the pump outlet hose to make sure. I checked voltage when I installed, will do again. Ground is 10 gauge directly to a ground hub, then to battery, engine block, body.
Bad new parts can wreak havoc on one's mental state. I will definitely be testing the new pump prior to putting the tank back in.

It runs damn good when it's good, doubling the psi plus some should make a huge difference.
 
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