Fuel Tanks and Internal Pumps...

[Firebirdjones]

I've done a LS 6.0 swap in my blazer a couple years ago. I'm tired of the external fuel pumps dying every 15-20k miles. I'm going internal now for longevity reasons (it's my daily driver) and it just left me stuck in the desert and 110 degree heat.


I've already been in contact with NMWP up in Oregon about their custom made 37 gallon tank as I like the idea of extra fuel capacity and I don't really want to fool with in tank electric pumps on this crappy plastic tank I have now.
I'm about ready to pull the trigger on this $700 tank but I'm waiting for them to get back with me to confirm it will accept an internal pump and if they have an internal pump setup in kit form. Add just says it comes with mounting hardware and a sending unit that works the stock gauge (0-90 ohms).

I need to have 58-65 psi for the LS engine to run properly, so the internal TBI pumps some of you guys are doing won't work for me. I also don't want to move the frame structure (which the larger 73 and later tanks would require) hence the reason this custom 37 gallon NMWP tank interests me (direct bolt in).


Whew,,,, Now with all that explained,,,what have any of you done for intank fuel pumps? Something capable of fuel pressure mentioned above...

Anyone that has dealt with NMWP chime in. I know there were a few as we have talked about this before. I'd like any details before I plunk down $700+ for a tank and fuel pump. Thanks.

[Firebirdjones]

Pulled the trigger on a 37 gallon NWMP tank with a built in fuel tray sump for an in tank fuel pump.

[BobbyK]

I heard their packaging sucks.

[Firebirdjones]

Packaging as in how they ship it??

As far as that goes, you have to request it be boxed up (which I did) otherwise it's shipped as a bare tank.

[BobbyK]

Yup, What you said.
Sucks you have PAY extra for that.

How it's shipped seems to be the only complaint with these guys.

[Firebirdjones]

Yeah I talked to them about that. It's made of 16 gauge steel so it's pretty robust. I wouldn't expect any damage per say, but it may get scratched or something. I asked that it be boxed anyway. We'll see when it shows up. If I have to spray it, it's not a big deal.

Pretty interesting though, I found that they build and sell about 30 of these a month for the little ford bronco's, that's their most popular tank. He only builds and sells a handfull of these for blazers so not as many.

I'll revive this when it shows up and snap some pics.

[mcmlxix]

You can check my K5 build, but I am paying my friend to weld a stainless tank for me that I may have cut on the waterjet(depending on price.) I ordered a vaporworx fuel ring that uses a factory 2005 Sierra/Silverado fuel sending unit with internal regulator. It also uses the factory O ring seal and camlock to secure it in place.

I was originally thinking about the tank you ordered, but like the idea of a LS 6.0L factory fuel pump. I also decided to relocate the filler so that was part of my descision as well...

[Firebirdjones]

Originally Posted by mcmlxix

You can check my K5 build, but I am paying my friend to weld a stainless tank for me that I may have cut on the waterjet(depending on price.) I ordered a vaporworx fuel ring that uses a factory 2005 Sierra/Silverado fuel sending unit with internal regulator. It also uses the factory O ring seal and camlock to secure it in place.

I was originally thinking about the tank you ordered, but like the idea of a LS 6.0L factory fuel pump. I also decided to relocate the filler so that was part of my descision as well...

Actually, I can run a factory 6.0 LS fuel pump in this NWMP tank if I wish, (I paid the extra $100 for a factory style pump sump with a tray) but I'm going to be pushing more HP in my 6.0 in the form of a maggie, so I needed something more than that. The Walbro 340 I'm using is actually a direct replacement pump that works for the 5.7-6.0 applications.

I can't relocate the filler simply because keeping the outward stock appearance of the truck is more important to me.

All the other tank makers wanted dimensions to go by for building a gas tank (they offer them for trucks but not blazers) and I just didn't want to go down that road because if it didn't fit,,,,it was on me and I'd be stuck with it.
Since NWMP has been building these blazer tanks since 1975 I figured he had it pretty well nailed down That alone is worth extra money to me. So I could be sure it would fit the first time without any fuss. I also liked the 37 gallon capacity simply because we also use our blazer as the family vehicle for long road trips. At 22 mpg highway I could technically go 814 miles on a tank if I ran it dry

[BobbyK]

I also liked the 37 gallon capacity simply because we also use our blazer as the family vehicle for long road trips. At 22 mpg highway I could technically go 814 miles on a tank if I ran it dry

WOW...great range!
But that's about $150 fill up at $4 bucks/gallon.
It's all relative I guess.

Make sure you post pic's of the swap.

[Firebirdjones]

Originally Posted by BobbyK

WOW...great range!
But that's about $150 fill up at $4 bucks/gallon.
It's all relative I guess.

Make sure you post pic's of the swap.

I'm used to it, my 79 pickup has dual 20's

I'll get some good pics up of the tank and the swap.

[mcmlxix]

Do you already have the Walbro and can you post details on it? Pics. P/N. Are you upgrading a factory pump assembly?

[fxdxharley]

Originally Posted by Firebirdjones

At 22 mpg highway I could technically go 814 miles on a tank if I ran it dry

???? how in the world are you getting 22 mpg out of a 6.0L? i have a 2000 2500 with the 6.0 and it only gets 14.

[mcmlxix]

Originally Posted by fxdxharley

???? how in the world are you getting 22 mpg out of a 6.0L? i have a 2000 2500 with the 6.0 and it only gets 14.

He only drives down hill ....

[Firebirdjones]

Originally Posted by fxdxharley

???? how in the world are you getting 22 mpg out of a 6.0L? i have a 2000 2500 with the 6.0 and it only gets 14.

Custom tune by me was alot of it Getting rid of the MAF and going SD tune, custom air intake and a nice dual exhaust system with a cross over all helps.

My father has an 02 6.0 3/4 ton and he gets about 14 mpg too (stock tune, just a catback and intake), just what you are reporting. I can tell you the factory tunes in these things really stink. They leave a ton on the table.

It also helps that the blazer only weighs 4700 lbs. I run a mild 3.73 gear with 33" tires but they are only 10.5 wide and a very mild BFG all terrain tread. With this tall of tire it's not really overly geared with 3.73, and the 4l60 I use with a 3.06 first gear helps it get moving easily. It's not rasied up at all (stock lift). I also run dual electric fans (got rid of the clutch fan setup). Alot of other little things. All of this was chosen on purpose to extract MPG out of it. It's my daily driver so making it economical makes driving it easier to swallow.

[Firebirdjones]

Originally Posted by mcmlxix

Do you already have the Walbro and can you post details on it? Pics. P/N. Are you upgrading a factory pump assembly?

I ordered the pump (not here yet). It's a walbro 340 kit that drops into the factory fuel pump sumps.

Many places sell them for camaro's, mustangs, trucks, and even foreign stuff.

Most people go with the 255 version as that's enough to support about 600 hp.

I am upgrading the pump itself to give me a cushion on the HP limit, the sump for the tank is custom made (of course) to fit the 37 gallon tank because it's 15" deep. But the sump mimics the factory designs with baffles and trays and will mount a factory pump if you wish.
The upgraded walbro pump I'm using is the same physical size as a factory pump.

Does that help at all?

[themb2g]

I bought my tank from NWMP last year and couldn't be happier. The tank was the most well done product i bought on my build. it fit perfectly and looks great. I bought it to have a larger capacity as i thought it was dumb to have to fill up every 150 miles with the 20 gallon and 350.

I've done most of the same mods as firebird and cant wait to see if i get the same results. I was hoping for 16, but if i get 22 i will crap myself in joy.

[themb2g]

you can see the tank in some of the pics on my build thread too

[themb2g]

another thought too is that the tank holds 37 gallons, around 300 pounds when full. gas mileage may dip a bit as well as the back end when its full. i'm still waiting to see how much the blazer squats on a full tank.

[Firebirdjones]

Yeah I expect it will squat a bit when you fill it up. That's about 220 lbs. of fuel

Actually it's only about another 100 lbs. of fuel vs filling up the 20 gallon tank.

I worked a long while on the tune to find that gas mileage. They are all capable if setup right and tuned properly. The problem for most people is finding a tuner that is willing to spend the time on it, with an eddie current dyno that can run steady light loads for part throttle tuning....then there is the cost of paying a tuner to do something like that,,,because it takes hours.

The sweet part with this EFI is being able to play with different fuel cells in various load conditions and commanding exactly the AFR you want, when you want PE, etc...

The stock truck tunes are lame (worse than the cars), with nearly zero timing in most cells, even under full load you'll find maybe 16 degrees total The throttle tuning section has alot to be found, seem there is alot of delay built in that can be tuned out, things that affect engine braking, and then the best part is playing with DFCO which cuts your fuel off when decellerating. Playing with these tables making it more aggressive usually finds 1-2 mpg. I won't bore anyone with details as you can literally spend days tuning and logging.

Neat build thmb2g, nearly identical to mine. I've heard the same thing from other people that you reported about your tank. Can't wait for it to get here (LITERALLY) as my wifes car is having issues, with my blazer down I'm having to resort to driving other vehicles that I don't want to really drive everyday. I'm anxiously waiting.....pics will follow.

[Firebirdjones]

NWMP Fuel tank and intank pump is all done, filled it up tonight.

Went pretty slick, not bad to install at all.

I'll start a new thread with pics of the install, and a few things I changed.

Maybe tomorrow,,,I'm beat and going to bed