There are four lines that come from the stock tank on a TPI car. a feed, a return, a line to evap system, and another (short) one that goes to what appears to be a breather. the car im building will be used for racing purposes and therefore will not have the evap system, this line will be removed and sealed. does anyone know if the "breather" line provides adequate tank ventilation on it's own? does anyone know the exact purpose of this line?

thanks!

 

If the car is for racing only and no street driving why not put a fuel cell in it?

Sorry, can't help you with the four different type of line.

 

My car is a daily driver and I sealed off the EVAP line, no problem.

But you MUST retain the breather. When the fuel pump sucks out fuel, air must takes its place as it leaves. If you seal off the breather, you will collapse your fuel tank.

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If you live in Southeastern US, check us out!
South East Thirdgen


ASE Master Tech + L1
Savannah, GA

'87 Trans Am
S/D TPI retrofit including functional PassKey,
22# injectors,
Ported Plenum,
TB Coolant Bypass,
SSM SFC,
Boxed LCAs,
8mm Accel wires,
Flowmaster Exhaust,
16" GTA rims,
Corvette Servo,
KYB Shocks

'97 Bonneville SSE

 

very helpful guys, can't thank you enough

 

GMtech if there is a breather then how come I have a hissing every time I get gas? I know it is vacuum because I dont feel any wind coming out of the filler. No way in hell you are going to collapse the tank. I have run full tanks through, it will suck air in for 20 seconds or so and mine is OK. Maybe if you have a hot tank and drive into a lake it will collapse....... Like on Bill Nye he collapsed a 50 gallon drum.

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Granted, yours may have not collapsed, but I bet it started to, how the hell would you know that it didn't collapse some? It buried under a muffler, rear end, and heat sheilds. Not to mention, you would have to wait quite a while untill you heard the tank "pop" back to normal (yes it does happen). Not to mention even if YOURS don't do it, not eveybody drives an F-body, I was just making a generalized description of what the breather is for.


Further more, since you are so damn smart, why don't you tell me and all the other members just what that fourth line REALLY is for, even though it is attached to something that LOOKS like a breather, and ACTS like a breather, but maybe I am wrong.



------------------
If you live in Southeastern US, check us out!
South East Thirdgen


ASE Master Tech + L1
Savannah, GA

'87 Trans Am
S/D TPI retrofit including functional PassKey,
22# injectors,
Ported Plenum,
TB Coolant Bypass,
SSM SFC,
Boxed LCAs,
8mm Accel wires,
Flowmaster Exhaust,
16" GTA rims,
Corvette Servo,
KYB Shocks

'97 Bonneville SSE

 

ah yes, the 'ol potato in the tank-vent gag.

thanks again :P