Surge tank location

sebch · Post by **sebch** » Thu Feb 16, 2006 2:31 pm

Hi,

I'm back in my MS project earlier than I thought and after successfully squirting my Volvo 122 (MS board 2.2, code 3.00, MT 2.25), it's now time to think about making things perfect. This includes adding a surge tank to the setup, because the pump runs dry often as soon as the tank is half-empty...

Lately I thought of a very easy way I could set things up, knowing that all the mods must be quickly reversible for the safety inspection every other year (the State in Switzerland doesn't like you to mod your car that much): I would like to use the plastic coolant overflow tank of any modern car and place it in the engine bay after modding the cap so no fuel can get out, which would then imply that the FP and fuel filter would be in the engine bay as well, somewhere beneath the surge tank.

What do you think of that?
Does the engine bay get too hot?
Any experiences with plastic coolant tanks being fuel-resistant (or not...)?
Also, what are my options to find an in-tank pump I could place in the tank without modding it too much? I'd like to find an external pump (so I don't need to fiddle with the tank) that would just fill the surge tank without pressure but not get fried when it dries up when cornering? DOes it exist?

Many questions, folks!!

Looking forward to your answers! Thanks in advance! Seb

bcal · Post by **bcal** » Thu Feb 16, 2006 4:28 pm

I don't recommend using plastic, especially if it not designed for use with hydrocarbons..

Even if it were compatable with your fuel it may rupture in an accident, especially if the fuel has made it go brittle.

old-colt · Post by **old-colt** » Fri Feb 17, 2006 5:34 am

Hi Seb,
You do not need much capacity for this tank, most of the coolant reservoirs are larger than you need. Maybe one of the micro cars has a small enough tank.
I do recall one that was a slim cylinder that may be suitable. I do not recall if it was VW or Volvo or what.
I would highly recommend one with a threaded cap.
I would give allot of attention to how the car would crumple in a nasty crash to select where to mount it, I consider this in the front or rear.
Can you fit one of the VW pump/ reservoirs under the rear seat floorpan, kind of where they put it originally. This would provide you with a ready made unit that has plenty of capacity for your application and would be mounted is a safe place.

lamrith · Post by **lamrith** » Fri Feb 17, 2006 7:39 am

Check out my EFI conversions page. I was having allot of problems with my fuel system and starving with my EFI conversion, this set-up not only gavee me a surge tanks, but it also put a nice easy to replace filter in the system...

http://www.mgbconversions.com/techroom/ ... system.htm