Using a 87-91 Tank and Pump for my Suburban

[5150]

Just checking to make sure, but I'm about to purchase a 91 suburban tank and going to use it under my 72 Suburban and the in tank fuel pump for my 5.3.

Any concerns on this setup?

[72gmcshorty]

just make sure you get the correct pump...

[5150]

Is there a wrong one? Will the factory one not suffice?

[clinebarger]

The stock 87-91 pump WILL NOT work, I run a 95 Impala SS pump in my 90 model Suburban tank that is in my 85 Suburban, Be sure to use 5/16" fuel injection hose between the pump & sender......The TBI hose WILL explode cause a massive fuel leak in the tank.

[Mr. 250r]

Don't alot of people run the walbro 255?

[5150]

Any other recommendations for fuel pump? Definitely plan on using the 91 tank, in other applications other then the 95 Impala? What do the specs need to be for the flow rate and the PSI to work in the 5.3?

[AJII]

TBI is about 15psi...LS motors need about 50.

[ls1nova71]

Ls engines run at 58 psi. I've used TPI pumps in the past but they only are supposed to put out 45 psi or so, probably about what the Lt1 pump from the Impala runs.
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[clinebarger]

The LT1 pump works great, It can make up to 100psi when "dead headed".
It's also fine up to 450 HP, I dont know the flow rate.

LT1's & 5.3's have very simular HP/TQ numbers.

[5150]

clinebarger, after I updated this post, I saw where you recommended an ACDelco one on ebay. I just bought that one.

[ls1nova71]

Originally Posted by clinebarger

The LT1 pump works great, It can make up to 100psi when "dead headed".
It's also fine up to 450 HP, I dont know the flow rate.

LT1's & 5.3's have very simular HP/TQ numbers.

I wasn't saying it wouldn't work, just stating about what pressure they're supposed to run at. My two cars with TPI pumps are both running true LS1's that put out over 300 hp stock. The pumps work fine, but people say you shouldn't use them. They are both AC Delco pumps. One car has over 120k on it and the other has 66k, so by my calculations they work great.
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[clinebarger]

Originally Posted by ls1nova71

I wasn't saying it wouldn't work, just stating about what pressure they're supposed to run at. My two cars with TPI pumps are both running true LS1's that put out over 300 hp stock. The pumps work fine, but people say you shouldn't use them. They are both AC Delco pumps. One car has over 120k on it and the other has 66k, so by my calculations they work great.
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I wasnt singling you out bud....Just commenting. I know you know what your talking about.

Ive heard to same thing about these pumps, Which is completely unfounded.
The Gen 1 Vortec CPSFI engines are regulated at 60-66psi & use a identical pump as the TPI/LT1 pump. Ive also cut open several LS1, LS-truck, LT1 & TPI pumps ALL identical number of vanes, Rotor height also the same.
The Walbro 255 pump is also the same Except has a 3/8" outlet vs. a 5/16" outlet on factory pumps.

The low pressure TBI pumps have fewer vanes & max out at about 55psi (dead headed)

[5150]

Okay, one last question. I got my pump in today and when I cracked open my "91" gas tank, there was no pump in the tank.

My question is will an "actual" 87-91 pump fuel assembly fit in the tank and work properly?

[ls1nova71]

The '87-'91 sender will fit the tank if the tank has the big sender, roughly 4" in diameter, but if it's not an actual '87-up tank it probably won't have the baffeling to keep the fuel around the pump when the tank gets low.

[5150]

I'll have to measure the sending unit outlet. It's one of real big tanks, but I'm not sure what year they had those big tanks.
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[5150]

Ok, I found something out about the tank. It was given to me by another board member. He told me that it came out of an 88 suburban, but it was a diesel.
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[clinebarger]

Originally Posted by 5150

Ok, I found something out about the tank. It was given to me by another board member. He told me that it came out of an 88 suburban, but it was a diesel.
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The tank may still be baffled? I dont see why GM would make 2 different tanks, But make sure first....A 40 gallon tank NEEDs baffling for a in tank pump.

[5150]

Stupid question alert, how can I tell if it's baffled?
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[clinebarger]

The tank will have "divider" walls running top to bottem within the tank.
Not just a hollow tank.

[5150]

It is not baffled, sucks, I had been planning on using that tank.

What about the 88-98 burb tanks? I'm not sure what shape they are in.

[clinebarger]

Square body Suburbans ran from '73 to '91 The next body style "GMT-400" Suburban ran from '92 to '00, For a 67-72 Suburban....I would use a 87-95 G-series van tank.

[5150]

Found a 93 at the pullapart. Are you certain the 93 tank will fit? I know the straps are different, but I can figure something out.
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[clinebarger]

Originally Posted by 5150

Found a 93 at the pullapart. Are you certain the 93 tank will fit? I know the straps are different, but I can figure something out.
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A '93 G-series Van tank? Its been a while, May have to trim the frame rails a little, Van tanks also come in different sizes, So measure first.

[ls1nova71]

Every pull-a-part around here punches a hole in the tank to drain them. You're lucky yours doesn't, makes finding a tank that will fit alot easier.

[5150]

Oh no, they do here to. I can get it repaired though.
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