70 Gs Baffled Gas Tank Or Something ?

[Dave Hanlon]

I put a mallory electric fuel pump with return style regulator in my gs and it seems to suck air with under a 1/2 tank around corners and under acceleration . do they make a baffled tank that will fit my gs? or is there a trick or mod i can do to the tank or sending unit ?
Thanks DAVE H.

[Jim Weise]

All 71 and 2 tanks are baffeled. 70 is not.

This was due to the change in the emissions system after 70.

JW

[RACEBUICKS]

Actually if you find a 70 GS or skylark from California it will have the baffled gas tank. My wifes 70 GS Stage1 came from CA and all of the emissions junk and the tank were on the car. I also know if you race the car enough it will make the baffles fall loose inside the tank.......... yep it happened!!!! I have her tank still to be fixed someday if I want to put her car back to absolute original, but at least you can get a 70 tank. The fill neck is slightly different on a 71-2 tank so if you find those tanks you can have you neck taken from the 70 and put it on the baffled tank.

How about it CA guys have any 70 skylarks out there with emissions ??

[Dave Hanlon]

THANKS JIM AND MIKE .Looks like i will be changing the tank to a 71 /72 . Just have to swap the neck fron my extra 70 tank. thanks again Dave H.

[Jim Weise]

Actually..

It depends on the plant/ build date of the car.. as this was a running production change in '70... I did a '70 GSX, with the original gas tank in near perfect condition, that did not have a baffel. No doubt that it was the original tank, as it had the Final Body Production order stuck to it.

It also did have the CA emissions.. lines, carbon canister, the whole nine yards.. documentation also called it out.

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.. but I was talking about a new tank...


Considering how important a tank is for both operation and appearance of a vehicle, the $200-225 spent for a new tank is a wise investment. We put them in the "hot rod"cars here all the time, if they don't have one already. Complete with neck.. for that price.

So you would want to order a 71-72 tank... and the neck will work just fine.. just takes a little "adjustment"..

JW

[tlivingd]

is there any way to tell the diffrence between a 70 and 71-72 tank from the outside? I'm looking for a baffled one.

[gd2227]

Dave, I have a spare 71 tank from a GS. Just come down and pick it up. Sorry- no 4 speed :laugh:

Mr. Floor :Dou:

[copperheadgs1]

Dave, you will have to change the filler neck if you use the 71 tank. Also are you using the MAllory 110 or 140 and where did you mount it?

[nekkidhillbilly]

if you need a cheap alt use a 91-96 caprice tank they are baffked and bolt up

[kenbuick]

Jim,

Do the 71-72 repro gas tanks have baffles?

Thanks,

Ken

[Truzi]

if you need a cheap alt use a 91-96 caprice tank they are baffked and bolt up
Cool - I was thinking about finding something cheaper to replace my tank. Though I was sort of hoping for something with a bit more capacity that would fit.

[tlivingd]

if you need a cheap alt use a 91-96 caprice tank they are baffked and bolt up

where the heck do you find a 91-96 EFI tank? I've found 86-92 ones for non EFI online new. but can't find the later ones. Also I cant find a used one around my area because they punch holes in all of the tanks around here to drain them. -nate

[nekkidhillbilly]

ive saw some on ebay for a lt1 but the cars were tbi efi in the mid 80s 86 i think so they should be baffled i think the capicty on those are 24 gallons not sure roadmasters and caddis work too

[nekkidhillbilly]

http://www.1aauto.com/1A/GasTanks/Chevrolet/Caprice/GM411B/36130

this is a efi tank for the 86-90s it should be baffled

[87GN@Tahoe]

those caprice tanks, are they for internal, or external electric fuel pumps?

[nekkidhillbilly]

internal im pretty sure

[tlivingd]

if you need a cheap alt use a 91-96 caprice tank they are baffked and bolt up

I hear the roadmaster has the same tank as the caprice. Can anyone verify this?

[tlivingd]

I just recieved a 93 roadmaster/caprice tank. overall shape looks like it will fit thus far. (though the sending unit portion is raised) it's an internal pump and baffeling.
oh yea. it's Polypropoline <sp? or something simmilar. Really thick though. that will look weird looking at the car from behind.

[Mr Big]

Hummm...I wonder if that 94-96 Caprice internal fuel pump would keep up with a hot 464? Something that goes low 11's high 10's? :Brow: :3gears:

[tlivingd]

Hummm...I wonder if that 94-96 Caprice internal fuel pump would keep up with a hot 464? Something that goes low 11's high 10's? :Brow: :3gears:

the stock pump wont. but one of these may
http://www.autoperformanceengineering.com/html/fppumps.html

stock are 190 L/hr the ones on the site are 255 l/hr

[Truzi]

Do we have confirmation on the Caprice tank? Also, if it were just used to replace the tank, does the sending unit and in-tank electric pump cause issues? In other words, how much work is involved.

While we're at it, are there any newer tanks that'll bolt up yet have a greater capacity?

[tlivingd]

Do we have confirmation on the Caprice tank? Also, if it were just used to replace the tank, does the sending unit and in-tank electric pump cause issues? In other words, how much work is involved.

While we're at it, are there any newer tanks that'll bolt up yet have a greater capacity?

not yet. it will be a little while till I fully confirm fit. the sending unit should work (all GM use the same resistor rating) their maybe a clearance issue however with the height of the sending unit in relation to the existing 70 tank. the intank pump may cause an issue though... if you put the screen.sock on the bottom and extended the tube to pump level you should be ok. and let the mechanical pump do the rest, as long as it can pull up thru the screen/sock.