EFI tank discussion

[Bent77]

Between Gen Motors installed unit and conversions, we have a lot of conversation on here about tanks, sending units, et al
I am encouraging pictures especially so that folks doing swaps can get a better idea on some things

 

[Bent77]

In addition to square body tech and information, I want to discuss a conversation that @fastazz81 and I are having at the moment, and maybe some of the GM installed stuff on LS/LT platforms may enlighten us

We are both building/using Tank Inc conversion on our "Other Rides" for 58psi supplied EFI tanks to run the ProFlo4
System comes with the baffled tank and a Walbro GSS340 in-tank pump (spec's 255LPH)
However the fittings just off the pump transition to .230" before the 90* fitting that accepts a 1/4"NPT thread for the line fitting

Seems to us that this size is inadequate to support 500+hp

 

[Bent77]

 

[Babaganoosh]

Do you think that small amount of restricted size will make a difference? I suppose this is why most swap out the stock style senders for aftermarket.

 

[Bent77]

Do you think that small amount of restricted size will make a difference?

Small amount??

The sleeve on the pump outlet is .375" inside

 

[Babaganoosh]

Small amount??

The sleeve on the pump outlet is .375" inside

Well I meant length wise.

 

[Bent77]

Well I meant length wise.

That's open for some debate, but it is an obstacle to flow and pressure that the pump could only recover by having reserve capacity and pressure

 

[fastazz81]

My biggest question after looking at it is the 90 , wonder exactly how much that itself is a restriction.

 

[Bent77]

My biggest question after looking at it is the 90 , wonder exactly how much that itself is a restriction.

it opens up, but the next fitting steps it back down to .250"

 

[Bent77]

LS/LT style don't have this restriction, right?

@fastazz81 do the mopar pumps have a restriction on the stock setup?

 

[fastazz81]

I’d have to find one to look at , the diesels I work on have a lift pump in tank but they have a lot lower operating pressure to the injection pump but more flow , I know the line and I. D. Of the sending unit is bigger.

 

[Fastereddie]

I don’t have any documentation on hand but I’ve never seen any version of 3/8” or -6an setup have any issue feeding up to 450hp.

 

[Bent77]

I don’t have any documentation on hand but I’ve never seen any version of 3/8” or -6an setup have any issue feeding up to 450hp.

PTFE lines are only .310" internally

Both Steve and I are looking to be north of 500

 

[Babaganoosh]

I have a stock 87 tbi tank and sender, with my pump I have been told it’s capable of 600+

 

[Fastereddie]

PTFE lines are only .310" internally

Both Steve and I are looking to be north of 500

I’m running ptfe on my 383 in the k5 and Marc and Deon’s gen5’s . Matt also runs the -6an ptfe on the 650 hp lt4s. No signs of starvation but they do run almost 72 psi.

 

[Fastereddie]

My duramax runs -8an from tank to air dog lift pump then the factory line from there. Appears to be about 1/2” plastic line. But those run very low pressure like 12psi.

 

[cheavyk10]

Wouldn't the 255LPH pump also factor in here? I would say a 350LPH pump would be better suited for north of 500 HP.

 

[fastazz81]

My duramax runs -8an from tank to air dog lift pump then the factory line from there. Appears to be about 1/2” plastic line. But those run very low pressure like 12psi.

Ya that’s about what I’d expect, Cummins have15-18 psi to the injection pump in stock set up.

 

[Fastereddie]

Wouldn't the 255LPH pump also factor in here? I would say a 350LPH pump would be better suited for north of 500 HP?

Just depends if you’re running out of fuel or not. Pressure is what your system requires at all times. Volume just depends if your injectors can use it all at 95-100% pw.
If your pump doesn’t have enough volume, your pressure will drop at wot

 

[Bent77]

Wouldn't the 255LPH pump also factor in here? I would say a 350LPH pump would be better suited for north of 500 HP.

In theory that should be able to feed 630 HP (EFI), but alas that is part of the discussion



Heres one way of looking at it:

With a fixed regulator, it its not at pressure, you know it
If you have and adjustable regulator, you just keep cranking until you get pressure
The conditions that control why it isn't up to task are the same, but squeezing it off makes it look good on the gauge

then factory in what Eddie said

Just depends if you’re running out of fuel or not. Pressure is what your system requires at all times. Volume just depends if your injectors can use it all at 95-100% pw.
If your pump doesn’t have enough volume, your pressure will drop at wot

If the pump keeps up at WOT without pressure loss, it doesn't mean the pump isn't tasked out
the yang to that yin is that a larger pump may make pressure but it could be masking other issues that are not 100%

Thus having an imbalance or shortage somewhere may in-fact cause a premature pump failure