2gen fuel tank

[Olav]

Hi!

Think I have posted this before but didn't get any feedback :-)

The fueltank from a Opel Manta will fit well bhind the backseat of 2gen f-body. If relocating it to this place can we put the muflfers where the tank used to be. It's easier to gravity feed the EFI fuel pump. We will have to use a motorcycle or a similar fuel cap to fill the fuel tank. BUT will this mowing of the wieght forward and higher be very bad for the weight distrubution of the car?

Thanks
Olav

[Olav]

??

Olav

[barno68]

You are not moving the weight too far forward, so sould not be an issue. I don't like have the tank inside the car due to the potential for gas vapors in the cab of the vehicle, but it should work. Also, you can cut a fill lid out of a Eclipse or the like and weld the new panel to the rear quarter, would look really nice.

[Olav]

Thanks!

My plan is to use a filler from a Honda CBR 600rr. But my biggest consern is the weight distrubution. The tank I tried is from a Opel Manta and is made for this location, gas vapors is not a problem if i connect the tank like it done in the Opel. But as I wrote, i'm worried regarding the weight...

Olav

[70bird]

You are not moving the weight too far forward, so sould not be an issue. I don't like have the tank inside the car due to the potential for gas vapors in the cab of the vehicle, but it should work. Also, you can cut a fill lid out of a Eclipse or the like and weld the new panel to the rear quarter, would look really nice.

+1
JMO, but you should weld in a firewall between trunk and pass. compartment for safety sake with tank in trunk. I know without firewall it will not pass tech at NHRA or IHRA events.

[Olav]

Welding a firewall will probably strenghten the car anyway so thats a good idea for safty also. It's not done in the opel but this is a easy job and will not add much weight. Anyone have the "Brain" to do some calculations regarding weight transfer. Have posted this at NastyZ28 also. some say the moving of weight wil bee a big issue....

Olav

[70bird]

Moving a "full tank" 12-16" higher and at least the same distance forward has to have a neg. impact on weight distribution. Mainly raising your COG. I don't have the "brain" to quantify how much or prove it, but I think common sense tells me it will be a negative in that regard.

With that said, I have to wonder what the application will be. EFI?, Carb? How will you use the car? DD? Track only? Both?

Why not stay with a stock style tank and sump it, or install pump in tank? Would keep COG low, and you would actualy have a trunk albeit a small one. I had to ask myself these same questions with my 2nd gen, and came to the conclusion that it would be more street than track, and went with a Rick's tank with A-1000. Not that you NEED to spend that kind of money as you could build a similar arrangement with a stock tank. JMHO

[Olav]

I will mostly use my car for DD and some track. I have a 355 with EFI convension going on. As I wrote it will be easier to graviity feed the fuel pump and i can mount the mufflers were the stock tank sits.I wil still have some space left in the trunk. I have started modifying the stock tank but when I tried the Opel tank it fit very well. Maybe I will continue to modify my stock tank.

Olav

[Skip Fix]

Once in a buddies early 60s Chevy truck I saw the gas tank behind the seat. Kind of scarey with fuel that close. The 2004-2006 GTOs have a gas tank behind the rear seat in the trunk. Since there are rear speakers even it might not be NHRA legal.

[Analog-kid]

. The 2004-2006 GTOs have a gas tank behind the rear seat in the trunk. Since there are rear speakers even it might not be NHRA legal.

The GTO has a cage around the tank and a firewall. The Monaro had it underneath the trunk but it had to be relocated to meet U.S. crash safety standards when imported as the GTO. Seems to defy common sense but it is probaly more difficult to rupture the tank in a rear impact. As far as the change in weight distribution I wouldn't think the differece would be very drastic in a street car, But I could be wrong. Track car maybe a problem as weight transfer is more critical. The big issue for a street car would be how to do it safely.And whether the extra engineering and fabrication is worth the gains. Modifiying the stock tank would be easier.