307c tank

[Bubuseventy8]

How many of you guys that did end up using the GN tank have done the mod to the tank that Phillip did? I have the 307c tank and am using the racetronix uniting. I have seen alot of guys not do the mod. Was wondering who on here has experience with this. Thanks - Collin

 

[45CHI]

You can use either one of Spectre 306c or 307c, then I got a Spectre 87 Grand National sending unit, and TRE(brand) high pressure fuel pump. I lost all the picks of the tank and fittings I used, phone got ran over. AND I DID ADD THE TUBE FROM TANK TO FILLER TUBE( had it done at local radiator shop). Good turn out for me. You can try it with the tube and let me know how it turn out.

 

[Bubuseventy8]

I've got the 307c and the racetronix sending unit with pump. But I've only seen 2-3 people that had to do the mod to the tank. I was just hoping to see if this was an issue with the factory sending unit or the tank. I have seen the guy on ls1tech that modified his sender and doesn't have the blowback issue. I have also seen some guys not have the issue at all. just wanted more info before I go get the tank modified. -Collin

 

[79loserbluebu]

Modify the tank. I've got a replacement tank and the same Racetronix sender and didn't modify it. When I get my car moved to my new garage I'm pulling the tank and doing it

 

[Bubuseventy8]

so you've had the blowback issue. Guess its time to cut some holes.

 

[87SS-ZZ3]

I just got my Dorman 307c tank and a new GN stock sender. Can anybody explain exactly why the tank NEEDS to be modified? I know the problem with fuel backup in the filler but I mean why is it happening? If the tank is not designed correctly I see the need to modify. It sounds more likely that the tank is not vented properly thru the sender asm. The sender vent should be routed to the charcoal canister which I'm sure is long gone in most rides. It may be a problem later but I'm not gonna modify mine. I am keeping the canister purge feature in the LT1 swap tho.

 

[79loserbluebu]

It is the design of the tanks. The charcoal cannister is just a large tank to dissipate the vapors, not to help vent the tank. My vent is wide open as is most people's.