Steps in the Right Direction - Build Thread for my two Lightnings

In my case, it's a small fuel tank with an independent fuel pump that's supplied by the in-tank pump. It's basically a big step up on the inline fuel pump. It allows for an upgraded fuel system by only upgrading the "front" section of the system instead of having to plumb the whole thing, deal with a sumped tank and its issues, etc. It provides a reservoir for the stronger pump to draw from when fuel demand is high.

I have a 2.5L tank with a 250lph pump in it. That tank ties in downstream of the OEM filter and the return from it ties into the OEM return lines at the connection adjacent to the filter. The in-tank pumps circulate fuel through the surge tank and then back to the OEM tanks, and since they're operating at a lot lower pressure than stock, their output is a bit higher than the OEM ~100 lph. I have AN6 lines between the surge tank and the fuel rails, and the surge pump circulates the fuel from the surge tank through the rails.

Installing the regulator eliminated the pulsation in the OEM portion of the system. I could only get it down to ~23 psi and then ran out of adjustment. I ordered a cheap regulator off Amazon to replace the Aeromotive. Supposedly it's a 0-160 psi regulator, but I won't believe that until I see less than 20 psi on the gauge.
 
I'll post pics once I have everything sorted out and I'm totally happy.

So, in a bit of "don't try this at home," I did something yesterday that isn't hugely advised, but has worked so far.

When the system was building pressure against the shuttle valve, the surge tank pump was really quiet. Once I put the regulator in the supply to the surge tank, the pulsation in the supply to the surge tank stopped, but the pump (a Deatschwerks 250) got much louder, to the point of being annoying.

Since it was just a matter of rearranging a few fittings, I moved the regulator to the tank return, which cured both the pulsation and the noise. However, I don't really think the surge tank was made to be continually pressurized at 20 psi, so it's currently a bit of a risk. I'm hoping the new regulator will let me run that down to about 10 psi, but I won't know where the shuttle valve functions until I can turn the pressure down a bit.

No leaks so far, though!
 
lightngsvt said:
Apologies if this is a dumb questions, but what is a surge tank?
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It’s kind of like a mini storage tank with fuel pump(s). The OEM pump feeds the surge tank. It eliminates running out of fuel on 3/4-WOT. The surge tank because the surge tank uses a high volume pump(s). Google it and it will make more sense.
 
A few pictures. Don't judge the underside of my 300K mile daily driver. It ain't the red truck!

The shuttle valves need about 10 psi to function. The regulator isn't permanently mounted yet, and once I'm sold that it's all working the way I want, I'll remove the gauge. Also still need to cover the wires.

Also, the angle makes it appear that the surge tank is angled downwards in the front. The outer, rearmost edge (meaning the one farthest inside the rail) is lowest, and I have a pickup for the pump that faces into that corner.

filter and return.jpg
regulator.jpg
surgetank.jpg
 
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FMOS Racing said:
A few pictures. Don't judge the underside of my 300K mile daily driver. It ain't the red truck!

The shuttle valves need about 10 psi to function. The regulator isn't permanently mounted yet, and once I'm sold that it's all working the way I want, I'll remove the gauge. Also still need to cover the wires.

Also, the angle makes it appear that the surge tank is angled downwards in the front. The outer, rearmost edge (meaning the one farthest inside the rail) is lowest, and I have a pickup for the pump that faces into that corner.

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That's very cool
 
How well the surge tank has worked has made me decide to add one to the red truck to cure the stall on abrupt stop problem it occasionally has. I was looking at things like the Holley tank mat, fuel pump speed controllers, new tank with different sump, etc, but this seems like a very simple and effective fix.

I'm going to use a little carb system fuel pump to circulate from the tank to the surge. The rest of the fuel system won't change.

Trying to decide on tank size for an 800 hp 10 second full throttle run. My napkin math says 2.2 liters.

Sent from my motorola edge plus 5G UW (2022) using Tapatalk
 
Yep, you're correct. I was backwards a step in my conversion. A little safety margin built in, 0.85 liters. So I'll be using a 2.5 liter surge tank just like the one on the white truck. Plus, both the supply and return for the OEM tank will be submerged under acceleration, so the main pumps will provide their own makeup when they're outrunning the transfer pump.
 
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My chatGPT chat came up with 22.3 gallons so I must have missed something! But I did learn fuel is 20% lighter than water.
 
Rule of thumb is half of power in lbs of gas per hour. So:
800 hp = 400 lb/hr = 6.6667 lb/min = 0.1111 lb/sec
0.1111 lb/sec * 12 seconds (20% "safety" margin) = 1.3332 lb
1.3332 lb / 6 lb/gal = 0.2222 gal
0.2222 gal = 0.8403 liters

(Starting off with a rule of thumb and then doing this to 4 decimal places is pretty funny, but hey, why not)
 
Teaser

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Hey I think I have the calipers on my shelf if that is a JFAB kit. 2005-2010 mustang calipers. I have almost a complete 2010 gt on the shelf. Lol
 
A bad day and a good day...

I've been focusing on the rear end work (axle replacement, tubes welded, disc brakes, new lug studs, etc) to get the red truck back in action. I'd borrowed the distributor out of it when I did the cam swap on the white truck, and Saturday morning, I swapped the reman'ed base I'd bought into the white truck. Straightforward. I dropped it in close to on time, started the truck, it ran fine, and shut it down so I could setup to dial-in the timing. It made a little bit of a weird sound when it came to a stop, but the timing wasn't spot on, so I didn't think much of it.

It wouldn't restart. I lifted the cap on the distributor and bumped the motor and the rotor didn't turn. Well $%#@#$ the stupid roll pin must've sheared. Pulled the distributor and there was a little bit of damage on one section of the gear, but the roll pin was fine. I was baffled. But, oh well, I'll put the red truck distributor back in it.

I pulled the #1 plug to get the motor to TDC and there was almost no air movement in and out of the cylinder. The engine turned over but acted like it wasn't building compression. I shined a light into the distributor hole and bumped the motor... The cam didn't turn. Oh no...

So, I pulled the front cover, and this is what I found:
IMG_20230930_121505000.jpg
Cam is seized in the block. I have no idea how that happened. So, now I have to chart a path forward. I'd been intending to swap the motor out of the red truck into the white one, and getting a real motor for the red truck, but I thought I'd do that on my own schedule. I guess not.

Drove the red truck for the first time this year... Wow, how in the world did that happen??
IMG_20231001_131854996_HDR.jpg
I forget how much I love that thing.

Stay tuned.
 
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glenbartley said:
Hey I think I have the calipers on my shelf if that is a JFAB kit. 2005-2010 mustang calipers. I have almost a complete 2010 gt on the shelf. Lol
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It's the JFAB kit. It wasn't as straightforward as I thought it would be when I started on the swap, and the e-brake turned into a major pain, but it's installed and working. I hated having to "modify" my factory e-brake hardware, but it's done.
 
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