I want a 20+ gallon gas tank for EFI conversion. Options?

[TURNA]

Already have one--a 4L80E. My first two full tanks of fuel have only produced 11.75 mpg and then 12.35 mpg, and this is with 3.08 gears. I'm considering upgrading to 3.73 gears, and that probably won't help my economy any.

The FI will help a little but OD is the big fuel saver. Are you sure your control is working properly?

The 1999 Chevy Express 3500 only got 14 city 18 hwy so you are not that far off.

I know the Express is a big box but I am sure Chevy padded those MPG numbers just a little bit.

It's a big block they weren't built to save gas!!!!!

 

[565bbchevy]

Here you go, this should hold enough fuel for those long trips and the price comes out to just under $43 per gallon to hold it.
https://www.summitracing.com/parts/pyr-pe160-a/overview/

 

[pontiacgp]

I guess he will have to build up that BBC more to pull the extra weight.

that comes from my circle track days, an extra gallon can make or break a race but even in my vehicles I don't like to carry around alot of extra fuel unless I'm headed out on a long journey...

 

[454GrandPrix]

I guess he will have to build up that BBC more to pull the extra weight.

The FI will help a little but OD is the big fuel saver. Are you sure your control is working properly?

Yep. The converter locks up and everything.

Here you go, this should hold enough fuel for those long trips and the price comes out to just under $43 per gallon to hold it.

Wow--60 gallons? Sign me up!!!

I don't like to carry around alot of extra fuel unless I'm headed out on a long journey...

Perhaps, but nothing breaks up a road trip like having to stop every 200 miles because you're out of gas.

 

[pontiacgp]

Perhaps, but nothing breaks up a road trip like having to stop every 200 miles because you're out of gas.

but with all the trouble and expense for an extra 5 gallons that will only give you an extra 50 miles maybe after you put in the 3.73. Have you got any friends in the Air Force who could borrow one of these when you head out for a non stop trip.....😀

 

[ldr]

You will like the FItech. We are using spectra gas tanks, throwing their pump in the corner and putting a Aeromotive 340 in its place.

 

[64nailhead]

I truly don't see the need for the in tank pump. An inline pump/filter system is 10 times easier to install, cheaper, and easier to maintain - IMO 🙂. I practice what I preach about this to the point that we have two inline pumps - one inside of each frame rail lol.

Regarding your fuel economy, what are your motor specs - compression, cam specs, current fuel system, ignition, and exhaust. An EFI system utilizing an O2 sensor for fuel feedback should help your economy. If your cruise tune is not too close, then you might find a good increase due to the conversion alone. 11-12 mpg is poor if your 454 is in the 450hp range unless it's built with no concern for fuel economy.

Getting the tire size and gearing to run at a speed that keeps your motor in it's happy place has to be addressed as well.

 

[454GrandPrix]

Regarding your fuel economy, what are your motor specs - compression, cam specs, current fuel system, ignition, and exhaust. An EFI system utilizing an O2 sensor for fuel feedback should help your economy. If your cruise tune is not too close, then you might find a good increase due to the conversion alone. 11-12 mpg is poor if your 454 is in the 450hp range unless it's built with no concern for fuel economy.

Getting the tire size and gearing to run at a speed that keeps your motor in it's happy place has to be addressed as well.

Since you asked:

454 +.030" with 9.2:1 compression ratio
stock iron Vortec 454 heads
Chevrolet ZZ502 roller camshaft (224/234 @ .050, .527/.544 lift, 110^ lobe separation)
Edelbrock Performer RPM AirGap intake
Edelbrock 750 cfm carb (either 1407 or 1410 model)
electric "clicker" inline fuel pump mounted next to tank (since my block has no provision for a mechanical pump)
Summit brand HEI distributor, vacuum advance (which will *not* be controlled by the FiTech once it gets installed)
full-length headers (1 7/8" primaries, 3" collectors) bolted to a complete Pypes 3" system with x-pipe and RacePro mufflers
stock 4L80E transmission
tires are 26.1" tall (235/60-15)
3.08 rear axle ratio

Right off the bat, I'll admit this engine spins at lower RPM while crusing than I anticipated. For example, 70 MPH is only 2050 RPM with the converter locked. Even around town, my 50 MPH commute to work is only 1500 RPM. I'm thinking this cam wants a little more RPM for its desired sweet spot. This realization, combined with the fact that my slight rake apparently gives me room to eventually upgrade to a taller tire, is why I am planning to upgrade to 3.73 gears later this summer. Having said that, I will very likely install the EFI before I re-gear.

What are your thoughts?

 

[Bar50]

Each gear step is roughly 250 RPM in High or at 1-1 ratio. Does it still feel like its on the cam or loping at the 1500 RPM?

 

[drogg1]

Doing the math, those RPM numbers are spot on. That 3.08 rear gear really helps keep the RPM down paired with the OD transmission.