Fuel Tanks
 

I answered a Post on Pro-Touring and thought I would add it here also...

Back in 1993 I had my first experiences with a ’69 Camaro and add on EFI fuel pumps. I bolted the pump to the frame rail added a return port to the tank and started to drive the car. As I was walking back to my house after the car quit for the 2nd time I had time to reflect on where I had gone wrong. The stock ’69 Camaro fuel pick up sock was falling apart and sending crap from in to my pump causing it to fail.

I added a pre-filter and solved that problem. I left for One Lap of America and the engine would fuel starve at anything lower than half a tank on road courses. I also blew the high pressure fuel line off the fuel pump at Michigan International Raceway and had a large fire that year. (Kyle Tucker was driving at the time and had to bail out of the car) The fuel pump I was using only had barb fittings on it. The high cornering loads at MIS caused the line to pull part way off. But not enough to kill the engine.

•Lesson 1 Stock fuel pick ups won’t work
•Lesson 2 Don’t use barb fittings

On the Red Witch I used an ATL fuel cell with a remote mounted fuel pump. It worked fine just a pain to fill at the gas station with the foam in it. It also required cutting the trunk out of the car. It would pull down to about a ¼ tank before fuel starvation.

•Lesson 3 Fuel Cells work

When I was building the Trasher I added a “Fuel Bucket” to the inside of the stock tank. The ATL (http://www.atlinc.com/catalogs.html) (Page 20 – 21) fuel bucket had 3 check balls in it and the fuel pick up. I added a sump to the rear of the tank and put the fuel bucket in it. To get access to the inside of the tank I cut an access hole in the top of the tank. I closed out the hole in the tank with an ATL tank plate and back up ring. ATL no longer sells these due to a law suit. It also always seemed to seep a little fuel after you filled the fuel tank. I think this was due to the lack of a proper vent and pressure would build up in the tank and push fuel past the gaskets.

That system worked OK. I could use the fuel down to ¼ tank on a race track. I didn’t like the idea of cutting and welding the stock tank. I lined the inside of the tank after I modified them to keep them from rusting. It was all a pain. I used something similar to this on the Mule. Both of these set up uses external Bosch fuel pumps.

I had Ricks build me a stainless steel tank for Camaro X with the check balls and a fuel bucket in the tank and a Walbro pump in the tank. It worked OK and would pull fuel down to ¼ tank on track. On this tank Rick’s still had not sorted out the vent and it would push fuel out of the tank when full. I added a vent to the filler neck that tied into the Rick’s vent and seem to reduce the problem.

•Lesson 4 Fuel Buckets work fair

When I did Jack Ass I had had years of experience with low fuel handling problems at work.

A little background. People suggested using two fuel pumps and a surge tank. This will work on a race car but will not work in production. Fuel pumps need fuel to lubricate them. Transfer pumps will work for a while dry but not very long. If you plan to use electric fuel pump to feed a surge tank then some day you will burn up your transfer pumps.

What we came up with is a fuel pump setup that sits in its own buck the fills the bucket with “jet” pumps. Jet pump are siphon pumps that use some of the fuel flow to run through an orifice to create a pressure drop to pump fuel. Many factory fuel pumps have jet pumps. Many new cars have split fuel tanks and need one jet pump to keep the bucket full and one to pull fuel from the other half of the tank. Corvettes have two tanks connected by a transfer tube and Cadillac CTS’s have saddle tanks and a transfer tube. I had Hector at Rick’s build me a split tank for a ’69 Camaro with the ring in it to allow a stock CTS-V fuel pump module. The fuel pump module sits on one half and a ½” tube runs to the other side of the tank to pick up fuel.

During the Motorstate Challenge Charley and I forgot to put fuel in JA after the road race Saturday night due to doing a photo shoot. We went to the Autocross the next day. Again we forgot to add fuel. I did my 3 runs then Charley got into the car and made two runs. Waiting to make the third run he noticed the fuel gauge "E". Charley made 1 more run on the autocross course with no fuel stumble before we could get more fuel. So the set up we have will pull the tank to empty in a heavy lateral environment.

•Lesson 5 Stock stuff works!

I went through 5 tanks from Rick’s before I got something that I feel works. I would like to thank Hector for all his help building me one off tanks. I consider this all development. There later tanks also have the vent system working much better now.

A quick note on fuel pumps. If you run a big pump for a long time at low consumption like on Hot Rod Power Tour they over heat. (ask Charley or Jody) I like stock style intake pumps with FSCMs to step down the voltage at cruise to help to not heat up the fuel.

Now the down side – none of this is cheap. Just my 2 cents…

Mark :lateral:

great info Mark, and thanks for posting.

Jody

Great Info Mark
 

Could you post up a simple sketch of how you did the CTS-V deal? If it is proprietary to you or Rick's I understand. I am in the middle of working out our fuel tank at the moment. It will feed an EFI Wegner LS415. I have been doing research and then you post this here. Great timing. Anymore detail would be greatly appreciated. Thanks very much!

Thanks for sharing your knowledge Mark. I always try to do the same. :thumbsup:

Jody,

I remember reading that you thought the fuel heating problem you had on PT with the yellow Chevelle was due to running the fuel thru the hot engine compartment.

I set mine up with the regulator at the rear bypassing immediately to the tank. I have a Walbro 255 in a Rick's tank. I hope I don't run into any pump overheating problems as I plan to drive out to Columbus next summer (about 7 hours for me.)

Thoughts? Mark, Jody, Bueller, anyone?

the fuel returning from the front mounted regulator was smoking hot due to a variety of reasons I'd guess; much bigger pump than required (A1000 Aeromotive), no pump controller to slow it down, fuel rails and engine compartment heating the rails, lines, and regulator, chrome plated intake and rails, etc. If you bypass at the rear it's not likely that the fuel will get warmed much at all. Mine is that way, and after driving 150 miles to Hot August Nights last year the stainless tank wasn't even warm.

Jody

I too would love to see a sketch of your solution Mark and Thanks for the info !

Jim

I asked first! :P How's that German Vette coming?

Okay -- Now I'm really confused!

I thought the whole purpose of having a bypass regulator was that the fuel was returning to the tank "continuously" -- keeping the pump running fuel - thus cooling it - and the large tank (in my case - 25 gallons) helping to act like a heat sink and cool the fuel.

I'm running the Aeromotive 1000 - externally - with an Aeromotive by-pass regulator.... I do not run a pump controller... it's just run by the Accel Gen 7... Fuel pump lead to a relay...

Are you saying that my fuel is getting "smoking hot" by the time it returns to the tank - and that I could have an overheating fuel pump??

where is the regulator?