Fuelie with twins?

[AceX]

I'm just in the information gathering stage of my swap to a big shiny LSX motor and I'm trying to figure out if you can run the stock twin-tank set-up.

I'm just trying to figure out a way to make the switch system work and keep fuel pressure up high enough.

Do any of you guys know what I can do to keep the twin tanks, or at the very least both fill points?

I had though about swapping to a suburban or Blazer tank then doing custom filler necks, but I want your guys' input. Maybe we can get some ideas flowing.

[mike nutt]

acex,
what year is your truck? i 've got an '86 with dual tanks also and it's going to have an ls1 or and lt1-4. if it's an '87 it would be easy.

[Wild83C10]

I can think of two options. Two individual in-tank pumps. Or you can gravity feed an aftermarket electric pump, which means you would have to install sumps in each tank.

[Cherub]

For a stock operation you need a new switch and a switching valve, along with two sending units and intank pumps. Whatever you use it needs to be rated to atleast 50 psi. There is a link on here for a biofuel switching valve that may work. Hope that helps. I just took the easy route and droped a tank and stuck with one lol.

[AceX]

My truck is an '85 with carb.

So do you guys think that simply swapping pumps and sending units will do the trick? Just keep the power for the pumps on a switch?

What about a frame mounted pump?

[crawdadfox]

Street & Performance has the set up you need for your "twins"....not cheap but top of the line stuff!

[Wild83C10]

Most electric pumps are pushers so they either need to be in the tank or gravity fed. You can put a frame mounted pump on as long as the pump sits below the tank and you put in a sump.
Probably the easiest solution would be to install in-tank pumps.

[Z POPPY]

I put a 1989 Tune Port 350 cid 5.7l IROC in a 1985 c10 silverado. I bought the 1985 new but the 305 5.0l was shot out by 86,000 miles. Here in Cali there are strict smog requirements. Smog legal swap with Cali BAR sticker. Smog test as a 1989 car. The 1985 had the c-3 computer cali system. It took me 2 months of studing wiring diagrams and 120 hours to do the swap and completed, more than just wires. I retained the stock factory tanks (No internal baffels, only on 87 and up models) built my own reservoir tank. No fuel starvation on corners but needs 2 fuel pumps to work. Here are some diagrams of what I did years ago on the fuel system. Drove it for 11 years. Gave the truck to my son, still on road. Here is some pics for you and everyone. But if you do it I want pics for my scrapbook of engine swaps.

[gchemist]

Install in tank pumps.
http://www.hotrodlane.cc/77chevytruck/77chevyp2.htm

[N2TRUX]

I thought you were talking about these kind of fuelie twins...

[JohnC]

That's sweet!

[thirdstreettito]

It'll work, easy! Think about it, diesels are fuel injected, most of the 82-92 6.2 diesels have 2 tanks, mine does. No skipping or anything. Plus I can drive FOREVER without have to fill up either one!

[AceX]

There's alot involved to make it like factory, but I can get all the GM parts from S&P. That's right, all factory, NOS parts. God Bless America.

I'm also going to be using hardlines where possible, and where I can't, braided lines with chrome fittings from Earl's. Expensive, yes, but this will be done right the first time.

Also talked to some people about the project today. Looks like a long road ahead of me, but some people may help out to make it easier on me.

When this swap is over, it will probably be the most factory looking and functioning swap around. Wish me luck.

[Captkaos]

Simple, For 2 tanks just get a fuel sending unit for an 87-93 pickup (not 100% sure on the end year) and run a corvette pump in it...

[Pyrotechnic]

Choose one tank as the main tank then put the appropriate pump in there. Put a TBI pump in the aux tank and use that to pump fuel to the main tank when necessary. Eliminates the switch valve all together. DirtyLarry did this for his Vortec 8.1 swap.