I'm going to tuned port injection. I read that the 87 V6 was fuel injected and the gas tank is set up for it. Does anyone know if the fuel pump mounted in that gas tank has a large enough return line to handle tpi?

If you happen to need to purchase a new tank, give these guys a look - http://www.rockvalleyantiqueautoparts.com/products.htm

Rock Valley makes some very high quality tanks. I've seen their work quite a few times and it impresses me every time.

They can custom make anything, you just need to give them dimensions and a working sketch of what you want.

Good Luck :)

It can handle it. That's the tank I installed in my LT1 setup with a Walbro 255 intake pump. And it's not the pump but the tank sender that has the return line.

Ahh, the wonderful fuel tank swap for EFI/TPI...

-----First of all, yes, the 87 TBI V6 tank will work perfect. BUT, you'll need the sending unit for that tank as well, as that's where the fuel pump goes. I bought my tank (a Canadian-made reproduction) for less than $150.00 brand new. However, the sending unit, as ordered from GM, set me back almost $300.00!!! And that didn't even include the fuel pump! (I ended up using the one from the IROC after installing a new sock (filter) for it.)

-----Also, beware of the Canadian aftermarket tanks... My filler neck was only soldered onto the tank instead of welded. When I put it into place, I noticed the filler neck hit the frame while I was jacking it into place. Of course, within the first year, the solder joint cracked, and now it leaks gas when the tank's full. :mad:

-----Best of luck on that upcoming swap!

Poltergeist,
I just got my '87 efi tank as well as the Walbro 255 pump. Thanks for the help. My application is a '79 elky. Which sending unit should I get that will have a return line? Will it work with my gauges? Is the vent in the sending unit?

I used the V6 fuel injection sender. Has all of the connections for FI, GM part # 25092938. I got it from gmpartsdirect.com it's about $180.

It should work with your gauges and it does have the vent tube on it.

I used the V6 fuel injection sender. Has all of the connections for FI, GM part # 25092938. I got it from gmpartsdirect.com it's about $180.

It should work with your gauges and it does have the vent tube on it.


HMMMMM......... I just opened up the box this tank came in and all I see is one hole for the pump. Now I'm confused. Is the sender and pump bolted together as a unit somehow?

Hotrod,
-----Yes, there is only one "hole" in the tank where the whole "fuel sending unit assembly" goes. This "assembly" contains the fuel gauge float, and also has three lines going into or out of it. One will be connected to the in-tank pump, the second is a return line, and the third is for a vent tube, or on smog-controlled vehicles, the vent line goes all the way up to the black "carbon canister" in the engine compartment and uses engine vacuum to "recycle" the fuel fumes. Here's a picture from an '87 V6 Celebrity, which is simliar: http://discountgastanks.com/images/pic_sunit_340_240.jpg
----- I actually got rid of my carbon canister, since I don't have to pass a smog inspection, (and I needed the space to mount my air cleaner) so I used the existing vent line from the tank to the carbon canister as my new return line. I then used the third line as a vent tube, with a check valve installed to prevent spillage.
-----Hope that helps!

p.s... THIS (http://www.jagsthatrun.com/Pages/Chevrolet_TPI_TBI_V-8.html) site offers a great book with everything you'll need to do your swap. I highly recommend it!!!
-----I think you can also order that book from Summit as well.
:D

How does the saying go? A picture is worth a thousand words. Thanks guys. Without forums like this one it would be a whole lot harder to do this. :-D

Hey Neversatisfied, I'm going to use an '88 GTA as a donor for an '81 Elky, and have thought I'd use the sending unit assembly out of the trans am rather than spending any more $ on finding a baffled tank and sending unit from a V6 elky. Did you have to do anything to the sending unit of the camaro for it to fit in the stock tank? My friend installed TPI in his '86 Chevy truck in the stock tank (without baffles) and hasn't had any problems with it, so I'm not really concerned with the baffles.

If you want to use the old tank, try an external electric pump from your local NAPA store for about a $100 and run a new return line. I attached it to the tank by installing a new bulkhead type of fitting in a hole that I drilled in the port where all of the other lines come out of the tank. I first tried it without the cannister and was always smelling gas fumes from the tank. Also, if you dont vent the tank, it can build up alot of pressure, especially in the summer. The gas tank is not really a pressure vessel either. Use the cannister. I have heard that there is a high pressure pump that can be installed as a direct replacement for some of the units, but couldnt find one for mine that was reasonably priced.

If you happen to need to purchase a new tank, give these guys a look - http://www.rockvalleyantiqueautoparts.com/products.htm

I talked to Scott at Rock Valley last night. While they don't have a pattern for a 22 gal baffled version, they can reproduce the 17 gal. tank with baffles & all kinds of other cool stuff...for a mere $959 8O

You guessed it, I'm still shopping....

I've been running my TPI converted 350 since June with an external fuel pump and have had no problems what so ever. I added a 3/8 in return line to the stock sending unit and used the existing fuel pick up for the feed line I also retained the canister vent. The pump is mounted on top of the rear frame rail just at the rear of the tank, this provides some protection and also mounts the pump below the tank level. I try to keep the tank at least 1/4 full to prevent cavitations. When I completed the installation the temperature in Texas was over 105 degrees and since then I've run it at below -5 with no fumes or any other problems. The pump I used is and airtex equal to an ac -185 it comes with a lifetime guaranty and was purchased form auto zone for $97.00. I checked the fuel pressure and at idle it puts out a sustained 40 psi. with good increased response at all RPM above idle. There is a center baffle in the stock tank which does help prevent sloshing to some degree. The only time I hear the pump is when I first turn the key before the engine starts. I am very pleased with the results of this installation. It beats having to drop the tank should I ever have to change the pump down the road.
Harald K.

I agree Harold. I did the same and it sure simplifies the job. Used the same tank, sending unit and everything except for the pump and a return line. I too have had zero problems and recommend this if you want to save a few $$$$$$$

My first setup was an external pump. I hated the whine of that pump. It was horrible at idle. That was the biggest reason I just HAD to go to an internal in the tank pump.

I guess I'm just not bothered by it since I've never noticed any noise from my pump with the engine running. Maybe my exhaust is too load, or my hearing is to far gone, maybe I just play the radio to load. Actually there is a big difference in the various external pumps but properly insulated and mounted most of them are barely audible anymore. My wife has very good hearing and she can't hear it so life is good. Considering the hassle and expense that you go through installing an in tank pump I'm very please with my end result.
Harald K

Other than the factory charcoal cannister, what are good ways to terminate the vent tube? I'm also not clear on exactly what kind of "check valve" some of you are using for this application. I must be missing it in the JEG's and Summit catalogs.

Thanks as always.