What is required? 3rd gen sending unit? What is the weight savings?

 

I want to know the same I just took out my metal tank today would love to use a plastic one.

 

Through research I have read in the past I "second hand" have been told they are identical and bolt right in and hookup just like the stock metal tank does to the stock sending unit assembly.

Also have been told that every 4th gen plastic tank is baffled also. There was no unbaffled options so all of them are good.

 

I want to know if you buy the thirdgen sending unit and put in it or do you have to use the 4thgen just I heard some of the connections were different.

 

I've heard this as well.
I've heard there is 18lb difference between the two.
I've heard the plastic tanks store an extra gallon or gallon and a half.
I've heard the 3rd gen sending unit can be used, or drill a hole in the 4th gen one. The charcoal canister is on top of these, so some modification may be necessary in terms of fuel/vacuum lines.

I like the idea of the baffles and the thought of it being plastic instead of metal and possibly rusting (though galvanized) etc. 18 lbs weight savings isn't A LOT, but hey, its 18lbs.

 

Hmm the charcoal canister is on top insteresting i wonder if i could get rid of the stock one then. I wonder if anyone has pictures.

 

18 lbs and a bit safer too. I'd love to see details on this swap.

 

from what i've heard the tank will bolt up in place but the connections are different, also the plastic tanks don't have the baffles that most people think of.. what it is is that the pump has basicly a cup on top that holds some fuel and will pull the fuel from there when the pickup runs dry

i have a plastic tank from an ls1 camaro sitting on my floor, so just name the pics you want and i'll get em for ya

 

pic of all the crap on top of this thing...

 

plastic is the same weight as steel......

 

I have trouble believing that the LS1 tank is 18 lbs lighter, i Just removed my tank and it hardly weighs anything. Maybe 20-25 lbs, if that. So what does a plastic tank weigh......5-6lbs?

 

I agree with 12secformula. I pulled the tank of my 91 and it was ridiculously light compared to what I was expecting. Is 18lbs really enough to raise the back of our cars? I wouldn't think it possible to notice any difference at all, although I could be wrong.

 

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Empty theres only a 3 lb diff, just weighed em.

 

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Pass the crack pipe.

 

Pass it this way, I want some of what he's got!!! J/K man

 

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Someones scale was REALLY REALLY REALLY broken.

Better have your Arm-Scale recalibrated.

 

Sorry, make that 1.5 lbs difference, got a 3rd gen tank that was completely empty, the last one had a tiny tiny bit of fuel in it.











I suppose you could argue that the fuel sending unit is Negative 12 pounds, yup thats what it is, space age anti gravity sending unit.

 

Now heres where i have to question you again, you post that it just plugs right up etc.

The fuel sending unit here in the one i have is roughly 40 ohms empty and 240 full, about what you'll find online if you do a little research. The stock sender on a thirdgen is 0 Empty and 90 Full.

So when that LS1 tank is empty your gauge should read about half full, and about 1/4 tank or so, you'll have a magical full tank.

Care to explain how you got around this one and actually be of some help ?

P.S. this wont be for me, i've already got my own route around this issue, this would be for those with stock gauges like yourself.

 

Hell if its a lb difference im not even changing it.

 

My thoughts exactly, I was curious about the plastic tank also......then I researched alittle and found very little difference in weight, and more work than it was worth. Then I pulled out the stocker to put a new pump in it, and much to my surprise, it was quite light. I'll keep it!

 

I'm glad this is resolved! I can get the racetronix fuel pump kit for my baffled 91 tank much cheaper than the 99-02 kit from them.
My tank is in really good shape anyways.

Now if I could only find the truth about the 90-92 TBI vs. TPI vs. 1LE sending units.

 

Whats this fuel pump kit your getting drain have any info im redoing my whole car buying all new parts and i need a nice fuel pump for the 383 and i need a new sending unit.

 

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The facts are straight, do the research, the sender is 240-40, the bs in here is so deep from you we all need waders, you want to argue with me on the weight and I've even posted pictures of them on the scale, im sorry i guess my scale is completely haywire.

Apparently you have a magical sender i suppose. Yes i'll be right over so you can show me the exact same two tanks i have here, and posted pictures of, and on a scale.

 

You sure that hand isn't smacking the wrong part of your body? I"m thinking it needs to move down about 12"

-- Joe

 

the fact i dont have stock gauges


its funny how people dont think on this site

 

Says the one claiming a 20 pound fuel tank weighs 8 lbs.....

 

I didn't know anyone made a fuel gauge that'll read a 40-240 ohm sender yet?

spdfrk1990 - here ya go!
http://www.racetronix.com/product/RX..._Pump_Kit.html

 

Are you getting the 307 or 340 Im not sure which 1 I should get I might get a SC later on would I need the 340.

 

The 307 kit. Thunder Racing has them also, but I doubt there cheaper than direct. Sometimes he has them on ebay also. I doubt you'd need one for over 60 psi. LS1's run at high pressures like that but if your injectors are sized right for your blower application your pressure should be lower. These may even have the plug and play wiring connections to add a kenne bell or msd boost-a-pump kit. I know that used to be an option. At that point though your fuel lines are gonna be the bottle neck, not the pump. I talked to the owner of racetronix for a good while one time and he is VERY knowledgeable. Rest assured that it is a good product.

 

You can use either one actually. You're regulator can adjust your fuel pressure down to whatever your car prefers. My buddy (89irocn2o) uses the high pressure walbro pump on his car and it's worked fine for years.
I'd email racetronix and tell him what you have and what your plans are and see what he recommends. Also ask him if those include the series 2 harness. That has the provisions for the pump booster. I can see that being necessary if you would add a descent blower!

 

ahh wha?? No!

You need to step 1:1 with boost. Most people tune at 50psi with vac disconnected. At 10psi boost, that should raise to 60psi with the 1:1 regulator. 15psi 65, and so on.

If its a boosted car, and you get anything less than a high pressure version walbro, then you just wasted your money.

The only thing you want to be LOW is your injector pulse widths, and thats about injector sizing.
-- Joe

 

Thanks for clearing that up Joe. I'm yet to use a blower, so I wasn't aware of that, but I did advise him to check with racetronix first to be sure.

 

Can someone who has one of these tanks sitting around please verify that it is indeed baffled? I've read conflicting comments.

 

No the 99-02 plastic tanks are not baffled. The tank isn't designed to work that way. The sending unit is designed so that the pump is constantly submerged in fuel. If you want a baffled tank, just get any from a 90-92 f-body. If it's the original tank...it's baffled. G92 cars from 88-89 supposedly had them...but I'd verify it first.

 

this is the "baffle" in the LS1 tanks, fuel pump sits inside and the cup stays full of fuel. when you go around a turn and fuel is no longer covering the pick up, the pump pulls fuel from the cup.


get it now?

 

What's the resolution for the stock fuel gauge and the 4th gen sending unit?

 

I'm wanting to know this as well... can we use the stock fuel gauge w/the 4th gen tank?