Can an '87 fuel tank be used in an '85 with out the added expansion tank?

Thanks,
Nick

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Nick D.
'88 Fiero GT 5-spd
'03 Jetta GLS TDI 5-spd

I asked my Mechanic this question, and he said he's never seen a car with one,so according to him yes you can (leave it out).

[This message has been edited by James Bond 007 (edited 07-27-2011).]

The expansion tank is needed to make up for the space lost inside the tank for expansion. Part of the increased capacity of the 87-88 tank was the relocation of the expansion area to an external tank.

[This message has been edited by Xanth (edited 07-28-2011).]

the expansion tank is required to keep EVAP can from being poison by liquid fuel.
When you fill a 87-88 main tank, expansion tank saves gas from exiting vent tube...
Goes from cold underground tank to warm/hot car tank, gas will expand. engine return line doesn't help... Returning hot fuel will make tank even hotter. driving/parking on hot pavement just bakes fuel tank.
main tank temp can, usually will, be above ambient (air) temp.

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Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)

The Ogre's Fiero Cave (It's also at the top and bottom of every forum page...)

GM does durability testing to the extreme and it also must protect the car from people intentionally overfilling the fuel tank... not that fiero owners would ever do something to get an extra gallon or two of gas into the tank.

From another thread...

quote Originally posted by fieroguru: Fuel expands/contracts with changes in temperature and it is important to ensure there is enough room in the tank for it to expand or it could push fuel into the evap canister. Gasoline expands at a rate of 0.00069 per degree F. So a 100 degree change in temperature with a 12 gallon tank will require .828 gallons of additional space. Expecting a 100 degree change is probably extreme, but it provides a sence of scale. Since my car is an 88, it has an external expansion tank on the upper passenger frame rail (I never measured it, but it might be .5 gallon). The top of the fuel fill vent tube is about 3" from the top of the tank. This creates an air pocket about 3" x 7" x 20" which is room for about 1.8 gallons of fuel (1 gallon more than needed for a 100 degree change - and assuming there was no secondary expansion tank).

So what I'm hearing is that its not a good idea to replace the '85 tank with an '87 tank?

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Nick D.
'88 Fiero GT 5-spd
'03 Jetta GLS TDI 5-spd

Not without the expansion tank.

Thanks

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Nick D.
'88 Fiero GT 5-spd
'03 Jetta GLS TDI 5-spd

anyone know what year fiero fuel tank I have installed, the person I baught it from said it was from an 87 fiero and it has no expansion tank????Its definatley an 87 or 88 larger tank.

Both the 87 and the 88 should have an expansion tank, unfortunately its a bit of a bear to get to.