moliver

Redline:

Slightly off topic, but have you felt any ill effects of removing the spare tire well? I would like to remove mine to better position a trans cooler, but have heard the rear end gets light at speed without something to occupie the volume.

tinman944

Hey John,
For some reason I am not getting any photo's today.
I am going trough the same deal of building a fuel cell for my 944.
I have also thought of the two tank idea.
Did you install foam into your tank?
Not sure if you know this.
The foam does two things. one slows down the sloshing inside the tank. second it slows down the fuel if the tank every bursts.
one down fall is the foam takes up a good amount of volume.if I remember right it is like 10 percent.(That number may be wrong.)
I was going to built a tank inside of a tank.
put a low volume pump inside the tank then a higher volume Bosch pump out side near stock location and plumb to the motor via filters.

RedlineMan

Speed?



It's an NA. Very Funny!

I don't think there would be a problem. If anything, the tire well probably increase drag and turbulance. The Turbo valance helps with that. At first, I simply sliced off the bottom portion of the well and made a simple cover plate. Then eventually my whole floor dissappeared one day. My car does not go fast enough to notice any difference.

Lemming

Have you thought about a 3L

RedlineMan

Yes Bob, we've heard the rumors about this car.

Mine does have the foam. The cost/benefit seemed to suggest using it. I agree with Kurt that the internal pump is a good idea. However, I can't quite get past the notion that Murphy would immediately put a slug in my foot if I did it. I can just see the pump crapping out at the track. Pulling apart a fuel cell is not a fun job.

I freely admit to being lazy and wanting this done and working, which meant leaving what was there already alone. If it does indeed work in solving the cavitation problems, I may very well reposition a lot of it.

Keep us posted. I'd be interested to see what you come up with.

RedlineMan

Umm...

I prefer personal speed.

See you at VIR again?

tinman944

Rumors of my car!!!!!!!! I hope none of the folks I have let in my garage are leaking info to the public.

RedlineMan

Wouldn't want it to be a reality... or even get finished!

tinman944

getting it finished is the problem....just when I think I have time to put into it another customer fills its spot.....

Matt Romanowski

Bob has a Jeep. That's the only one I've ever seen.

tinman944

Thanks Matt.....Lets keep it that way

Matt Romanowski

John,

Why didn't you use a duckbill like the circle track guys? We've used those and got the tank down to under a gallon.

In the FC, we run down to under a gallon. A friend had a FSCCA car go underweight becuase he had run under a gallon.

Matt

RedlineMan

Hey;

It already has a trap door surge tank in there now. Hinged doors that let fuel in but not out, and the hose pulls out of this box. The hinges face the passenger side. Didn't work. If an enclosed box doesn't work, I'm not sure how an open pickup would. Who knows?

kurt M

I am working on a system that has a ring shaped trap door in the floor of a cylindrical surge tank. The tank will slide through the fill opening and be set to the side to ease filling. Not influenced by G force or direction and the flap valve lifts up and fills the tank when the surge tank fuel level is lower than the main tank in the event of a surge tank pump failure or rather than a second pump. There are fuel safe materials that are almost as light as the fuel itself.
Another thing I plan to do is have any fuel return from the motor go to the surge tank, not to the main tank. Why put back fuel you just successfully picked up? Keep it in play until it is gone. This would be unneeded when the tanks are full but at the end of the main tank when the surge pump is hitting high % of air and for more and more time the motor return fuel will help keep the surge tank filled as the surge pump only has to replace consumed fuel. This does not require an added or moved return port, just add tubing to return fitting inside the tank and over to the surge. I am thinking that a well built main tank with foam and a surge tank that works with return fuel going back to the surge might not need the second pump at all.

Keep in mind that as it is now, your system, during any non pickup time by the surge pump has the motor fuel pump working against the surge pump. The unused fuel, first picked up by the surge pump then by the motor pump is being returned to the main tank and not the surge tank. Moving the motor return line from the main tank to the surge tank you now have will increase the last drop capacity of your system at no cost. There will be little to no change in back pressure as the surge and motor returns share a common T fitting now, just change where they share. Put the T on the surge and let overflow back to the main vie the existing surge to main return that is in place.

Open pickups are not bad at all if you use foam and set the pickup in the right place. There are a lot of folks that prove this right and do so every day. you might have a poorly working internal flapper box or setup.

tinman944

Kurt.
your Idea sounds good...It is the way that the early tanks where designed.
One thing to think about. put your return line as far away from the pick up as you can.
one the fuel is coming back warmer than what is in the tank , second there is a chance that there is a slight amount of air in the fuel that is returning.