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87 Baffled Tank in 77 Body Questions

ZombieK5

ZombieK5

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I am divided between getting a Holly Sniper EFI fuel tank system which includes a new 25 gallon tank or getting an Dorman (or similar manufacturer) new 31 gallon tank with a Walbro pump.

Has anyone put an 87 or later year style baffled tank in an earlier body like a 1977. I know the 77 has the round filler hole, I'm worried about tank FITMENT in factory provided locations?
 
No problem at all. I put a oem 31 gallon efi tank from a 87 in a 77 K5. Bolts right up. Only issue is the filler hose diameter is different but no biggie.
 
I did the same tank conversion in my 79 and went with the MSD Atomic because of emission inspections and roller tests. This summer will be the first time through to see if it passes.
 
My opinions on holley are known around here so = nope

Dorman quality is NOT what it use to be anymore . But sadly thats a lot of what we get just reboxed house brands but dorman junk .

Go spectra premium brand on the parts if possible . Then tbi sender minus pump and use a acdelco ep381 pump for 96 c3500 5.7 vortec and your done .
 
AFAIK, there is no aftermarket tank that has baffles like the factory TBI tanks did. The large factory plastic baffles do a better job of holding fuel against the pump when the tank is low. Unfortunately, they also break after a while and can cause problems. I'm not even sure those are available anymore. I have a Spectra TBI tank and it just has a little pan in the middle with small holes at the bottom. When the tank is low (like 1/8 tank), steep inclines or acceleration around a corner can make it starve. Not really a big deal and I've been living with it for years, just have to be mindful to have a little gas when heading off road. So if that Holley tank has better baffling, that's somewhat of an advantage. Maybe somebody has pictures?
 
Blue85 said:
AFAIK, there is no aftermarket tank that has baffles like the factory TBI tanks did. The large factory plastic baffles do a better job of holding fuel against the pump when the tank is low. Unfortunately, they also break after a while and can cause problems. I'm not even sure those are available anymore. I have a Spectra TBI tank and it just has a little pan in the middle with small holes at the bottom. When the tank is low (like 1/8 tank), steep inclines or acceleration around a corner can make it starve. Not really a big deal and I've been living with it for years, just have to be mindful to have a little gas when heading off road. So if that Holley tank has better baffling, that's somewhat of an advantage. Maybe somebody has pictures?
Click to expand...
I WANT to go with the Holley tank but they don't offer a 31 gallon, only 25. I rarely let my cars go below 1/4 tank. If the Spectra works above 1/8th a tank w no issues than I'm fine with it.

BTW, does Spectra seal the inside of the tank? Is the outside painted or coated?

Any horror stories out there?
 
Un sealed both in / out . Been running them for years up here in the heavy rust belt .

Wipe off the slime and scuff with red scotch bright pad and under coat it .
 
Blue85 said:
AFAIK, there is no aftermarket tank that has baffles like the factory TBI tanks did. The large factory plastic baffles do a better job of holding fuel against the pump when the tank is low. Unfortunately, they also break after a while and can cause problems. I'm not even sure those are available anymore. I have a Spectra TBI tank and it just has a little pan in the middle with small holes at the bottom. When the tank is low (like 1/8 tank), steep inclines or acceleration around a corner can make it starve. Not really a big deal and I've been living with it for years, just have to be mindful to have a little gas when heading off road. So if that Holley tank has better baffling, that's somewhat of an advantage. Maybe somebody has pictures?
Click to expand...
that sounds like the tank in my 88. always had issues down near the bottom of the tank. If i made a right hand turn hard i would run out of gas until the truck leveled out.

i assume its origional - one day out on the trail, the truck stopped GOING

 
I had some winching, and a long tow to the highway.
later found out that the tray broke off the bottom of the tank, and broke the fuel pump off of the sending unit assembly. Before opening it up, I was very confused- i could hear the fuel pump running and priming (i thought it was priming). It was just dangling by its wires and spinning in circles.

I cut up the plastic tray with tin snips or something, and pulled it out of the top of the tank in pieces. - no other baffling that i remember seeing. just a nylon tray that had been bonded in the middle of the tank floor

I would much rather have a well designed sump in the bottom of the tank, but that's not a project I want to undertake right now.

Note to self: don't go 4 wheeling with less than a 1/3 of a tank if I can avoid it.
 
These hyrdamats are supposed to fix all those problems, with no need for a baffled tank, although I have no personal experience with one.

Holley 16-105 15" x 3" HydraMat®, Rectangle

The amazing HydraMat® is Holley's patent pending design that solves the problems associated with traditional fuel pick-ups in stock fuel tanks as well as racing fuel cells. During hard cornering, acceleration, stopping, inclines, and low fuel conditions fuel runs away from the fuel pick up which...
www.holley.com www.holley.com
 
cheavyk10 said:
These hyrdamats are supposed to fix all those problems, with no need for a baffled tank, although I have no personal experience with one.

Holley 16-105 15" x 3" HydraMat®, Rectangle

The amazing HydraMat® is Holley's patent pending design that solves the problems associated with traditional fuel pick-ups in stock fuel tanks as well as racing fuel cells. During hard cornering, acceleration, stopping, inclines, and low fuel conditions fuel runs away from the fuel pick up which...
www.holley.com www.holley.com
Click to expand...
Unless they've changed them, the problem was they didn't just mate up with the fuel pumps like the sock filters do...if you could just stick it to the bottom of the pump, those would be awesome. Would make a whole lot of GM vehicle EFI swaps easy.
 
dyeager535 said:
Unless they've changed them, the problem was they didn't just mate up with the fuel pumps like the sock filters do...if you could just stick it to the bottom of the pump, those would be awesome. Would make a whole lot of GM vehicle EFI swaps easy.
Click to expand...
never seen those. i am untrusting of putting diapers in the ethanol.

interesting though. i keep thinking it would be easy to design a pick up tub for all 4 corners of a tank with some kind of gravity valve shutting off flow to the high sides... but who has time for that
 
The GM design is excellent, except they used plastic. Had they used sheet metal instead, tacked in before the tank halves were put together, there would be no improving the design.

I'm sure the terrible aftermarket designs are because it would take a lot of welding (read, more $$) to make a similar design sump, that didn't leak fuel.

Honestly, hydramat would be great, IF it mated up to a standard sending unit. They've been out long enough now that if they were not ethanol resistant we'd here of massive failures I imagine.
 
scouthead said:
I like that. do you have to shop vac all the gasoline out of the tank before welding it on, or just go for it??
Click to expand...
What kind of shop vac do you have that's rated for flammable materials? Welding in an old gas tank takes tons of planning and preparation - not something you'd do on the vehicle - so getting the liquid out is no problem. The issue is that there's fumes in there nearly forever unless you take more drastic measures.
 
When I am pulling old gas station tanks {2k to 4k gals generally} we put about 100 lbs of dry ice in them.
Supposed to displace the fumes and reduce the oxygen inside the tank.
 
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