Finally got my tank built by my buddy who builds aluminum marine tanks.
Physically the tank is the size of the old tank's widest and highest points but since it has sharp edges instead of rounded ones, and the sides were made to the width of the pinch welds on the old tank, it is actually a bit bigger than stock. For length, we had to actually make it a few inches shorter than the old tank at the front due to the sheet aluminum he had in stock, 48" and ordering new would require waiting for it to show up which means time that I dont have. Really when you look at how much we cut off the front, that very small area only would have held another 3 or 4 cups of fluid which we more than made up for with the rest of the dimensions.
The bigger dimensions also meant the straps need reworking which I was prepared to do, I cut some strips of thick sheet metal that I was going to then rivet onto the old straps to lengthen them. What I didnt foresee was the fact that the width made it very hard to get between the tank and floor pan of the car. Lying on my back I just gave up on them temporarily but plan to get it up on a lift soon to work with it in a much more natural standing position.
So whats holding up the tank? Well that cross brace in the center of the tank, when installed properly actually protrudes up toward the tank and is flat across the bottom. Without the provision in the tank for that brace to bump up in the middle, I had to actually flip the brace around using the flat part across the tank. My brace was drilled very unevenly so I had to elongate some of the mounting holes to get it up. Also with the tank sitting a little lower at the bottom (due to the squared edges up top) I actually had to put a jack under the brace and squish everything up real tight just to get the bolts started into the floor pan. Dont worry though, I didnt dent anything, not even the tank, its very rigid for aluminum. So now with the brace holding the tank up tight, I gave it a really good wiggle to make sure it wasnt going to go anywhere when driving, solid as a rock.
Now for more pictures, the rear of the tank was a critical dimension. The new sender had to fit just right so it had to be perfect. Also what I forgot to take a picture of was the new sender hold down. We got rid of the ring and made a new one that simply screws down into the tank. You can see the 4 screw holes around the sender here.
We also raised the vent tube on the rear, when filling up the tank, when the level gets up to the vent tube is when the pump shuts off. Raising this will increase my capacity, as long as I dont fill the car and let it sit hot long enough for the fuel to expand too much.
I plan to get him to build another tank for me, this time we will learn from the lessons on this tank and make it more "stock fitting" than this. Unfortunately this means losing some of the capacity that we have with this tank but I want to get him to draw up a good blueprint so he can replicate the tank easily if anyone here wants to purchase one from him. If/when that happens I will offer these for sale, not for personal profit, just as a point of communication between PFF and him. Final cost and such will be totally up to him and I will just announce what he offers.
Thanks, yes we did add some baffles, similar to the stock tank baffles. Its really just some plates welded to the bottom of the tank that span the width but dont close off the sides just in front and rear of the sending unit. This keeps fuel from flowing too fast to the front or rear of the tank on braking or accel. The main difference from stock is that in the stock tank, where the fuel enters the tank from the filler neck is actually a long tube that dumps right into the baffle. Ours simply dumps right into the rear of the tank. Fuel can flow all the way front to back though, it is just slowed by the baffles.
The main reason for doing this in the first place was that when I had my duke in my car, it ran fine. Once I put the 3800 and required 255LPH fuel pump in, it was sucking much more fuel as well as the rust in the bottom of the tank. My swap never ran right originally because it would lean way out from rust clogging the pickup sock. I tried cleaning the tank 2 or 3 times and everytime the rust would just come back in piles. I even pulled the tank from my other car and it was the same way. I bought some of the liquid tank sealant that comes in 3 stages in cans, to clean out the tank and seal it up with a membrane. The only problem was they suggested not using it in tanks with plastic parts because it may not stick to the plastic (our baffles) and could end up clogging the pump just as easily. Finally this was my solution. Get rid of the old tank all together and make one that will never rust.
The weight is virtually the same, the aluminum one may even be a hair heavier because of the thickness, but nothing thats going to make any noticeable difference.
And the tank is made from the dimensions of the 87-88 tank.
Thats totally up to Tony, the guy who made the tank. This "one off" was a test just to see if we were close and it does work, but isn't perfect. Hopefully he will have the time coming up to make another one so we can play around with some of the dimensions.
And if you really want to know, I didnt pay anything for the tank. We scratch each others backs and I think its my turn to start scratchin.
Sound like a excellent tank. Let me know when it finished so I can buy a tank from Tony. Oh yeah, it is possible to make it a bit longer? Maybe squeezing another gallon?
Yes, longer is very doable. I took some measurements of the opening I had with the tank removed before I went and started on the project. Even the stock tank doesnt quite fill up the front of the opening. That is really the only place to expand the tank without modifying anything else. It would just about come to a point at the front because of the angle up there, but I would think another gallon could be had without much trouble.
We need to set up someone or some company to start repoppin gas tanks... Thats the one thing I have noticed no one is making for out cars and it causes problems quite often... No one, and I mean no one seems to be making repo tanks for our cars...
Well I am not announcing anything official yet of Tony building these tanks, but if his business allows him the time to make a good fitting tank soon, with some test fitting and input by me, he has said that he would be willing and able to make these with ease. Being a custom tank builder, he rarely gets to make a duplicate tank (same size and shape) so once the dimensions are figured out and he can make a cut sheet for the aluminum parts and a build sheet with any information like tube placement and such, it would be easy for him to keep duplicating it because the thinking is done all he has to do is follow his notes. I honestly have no idea how much he would want to charge. I dont know how much the aluminum costs him, and I dont know how much time he has or will have into making these regularly. I do know the cost of aluminum fluctuates so it may be a set price until materials go up but he is and always has been a reasonable guy.
I met him years ago when he became a vendor that I use to buy a particular hurricane shutter type from, he put in the effort to become a manufacturer of Hurst products accordion shutters with Miami/Dade rating and offered them to me for a reasonable price. Since then we have become good friends, doing favors for each other which works out to both our advantages. He has always been honest on price and works with me when I am in a desperate situation. In other words, his business and personal ethics are top notch as is his craftsmanship. He has been making aluminum tanks for years and knows what he is doing. We pressure tested the tank when I went to pick it up, all the welds he did and not a single leak anywhere.
How do you handle the potential for galvanic corrosion due to the electrochemically dissimilar metals in contact (aluminum tank contacting steel used in the car body, supports, and fasteners)? If you don't have the tank well grounded (i.e. insulated from the chassis) you run the chance of static buildup in the tank with a resultant spark, perhaps during fueling. If you do have the tank grounded, you have dissimilar metals in contact and something (the aluminum) will suffer, especially in the presence of impressed voltage which may occur from sensors, ground resistance, etc. Since aluminum tanks are uses in lots of vehicles, there must be a solution to the possible corrosion. How is it done?
How do you handle the potential for galvanic corrosion due to the electrochemically dissimilar metals in contact (aluminum tank contacting steel used in the car body, supports, and fasteners)? If you don't have the tank well grounded (i.e. insulated from the chassis) you run the chance of static buildup in the tank with a resultant spark, perhaps during fueling. If you do have the tank grounded, you have dissimilar metals in contact and something (the aluminum) will suffer, especially in the presence of impressed voltage which may occur from sensors, ground resistance, etc. Since aluminum tanks are uses in lots of vehicles, there must be a solution to the possible corrosion. How is it done?
Paul McKibben Norcross, GA
Cathodic protection system?
Rubber - Nylon - Poly bushings?
or you could have it powder coated?
However I think it will be fine as is
[This message has been edited by Pappy (edited 03-17-2011).]
Any kind of larger tank would be an improvement. I am not getting very much range before having to refuel. Personally I would want the most fuel capacity possible even if is non-stock fitting design. I can deal with new mounting straps and hardware if need be. I'll be watching this thread for the final product. There was someone building a kitcar that designed a tank that was longer, his design had two additional saddle tanks but the center tank looks promising. The plans are posted there too.
How do you handle the potential for galvanic corrosion due to the electrochemically dissimilar metals in contact (aluminum tank contacting steel used in the car body, supports, and fasteners)? If you don't have the tank well grounded (i.e. insulated from the chassis) you run the chance of static buildup in the tank with a resultant spark, perhaps during fueling. If you do have the tank grounded, you have dissimilar metals in contact and something (the aluminum) will suffer, especially in the presence of impressed voltage which may occur from sensors, ground resistance, etc. Since aluminum tanks are uses in lots of vehicles, there must be a solution to the possible corrosion. How is it done?
These are good points Paul. Someone on here will know some answers. In my dealings with aircraft, I have found that most steel straps are wrapped with some sort of insulation material similar to sound deadening tar paper type stuff. As far as grounding, I would suggest a copper strap somewhere. The copper seems to have less corrosion issues with aluminum. (maybe because most aluminum is not pure and uses copper as it's alloy such as 2024T3? not sure...) The fuel pump and sender have their own ground which should be inside the tank running out into the body harness. I would think one would want to alodine, prime and paint the tank also.
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Intercooled SC3800 II/III mated to a Getrag. 19's with 13" Brakes on all 4 corners. 5 years Avionics & 15 years Car Electronics.
Sorry if this has been covered before here, but what's the stock Tank made out of? Just plain mild Steel? It rusts inside and out, so I'm guessing that's what it is right?
Any kind of larger tank would be an improvement. I am not getting very much range before having to refuel. Personally I would want the most fuel capacity possible even if is non-stock fitting design. I can deal with new mounting straps and hardware if need be. I'll be watching this thread for the final product. There was someone building a kitcar that designed a tank that was longer, his design had two additional saddle tanks but the center tank looks promising. The plans are posted there too.
I researched that link long and hard before making this tank. We did use his blueprints as an idea of some of the room we had, but didnt copy them in any way. He made his tank longer and actually had to remove all the bits at the rear of the tank including some of the structure and is no longer using the stock sending unit/pump. My plan was to fit the width and height of the tank to the extremes, as the builder there did too without compromising anything on the car itself.
If the demand is there, when I get the tank back out in a month or so I will fill it and see what kind of capacity I have with this design and if its big enough, we could offer this design as well with some information on modifying the brackets.
For the metal dissimilarities, I hadn't thought that far ahead yet. I will probably end up wrapping the tank with a thin foam insulation material and running a ground strap to it. Anyone have some advanced knowledge on this topic want to chime in and give some advice? I certainly dont want to offer a product without knowing stuff like this. I do know the fuel pump is grounded through the wire harness back into the car itself but the level sender is grounded right to the tank.
And I would guess the stock tank is just steel. The car it came out of was rust free EVERYWHERE (I just had it down to bare frame for a panel off paint job) but the inside of the tank was like piles of rust. Outside looked fine, but I assume its because the car sat for a while.
I was working on a friend's '67 Pontiac GTO last fall when I noticed his tank was made entirely of fiberglass. I was surprised since I didn't think fibreglass resin would be chemically resistant to fuel, but then maybe it has a special coating on the inside. Regardless, aside from possibly needing a sheet metal rock-guard can anyone see what the problem would be in having our tanks made of fiberglass? The advantages of cost, and ease of fabrication are obvious.
You could probably use a DIY truck bed liner This would also add an extra layer of protection
Durabak Dupli-Color Bed Armor Grip-Guard Grizzly Grip Herculiner
I was thinking the same thing, but not DIY... The DIY stuff is a pita and requires many coats to build-up a reasonable thickness. Not to mention it is not as durable as the high-pressure professional spray on liners... I have Rhino in my truck, it is there "extreme" high-pressure product. It is basically like an almost hard plastic...
I was working on a friend's '67 Pontiac GTO last fall when I noticed his tank was made entirely of fiberglass. I was surprised since I didn't think fibreglass resin would be chemically resistant to fuel, but then maybe it has a special coating on the inside. Regardless, aside from possibly needing a sheet metal rock-guard can anyone see what the problem would be in having our tanks made of fiberglass? The advantages of cost, and ease of fabrication are obvious.
Not too sure how a fiberglass tank would react in a crash... I wouldn't trust one not to crack...
Looks like a good opportunity for a side line business for Tony. Quality Fiero gas are most difficult to find. Since Fiero people are notoriously cheap, keeping the cost to <$300 would be a great deal.
I was working on a friend's '67 Pontiac GTO last fall when I noticed his tank was made entirely of fiberglass. I was surprised since I didn't think fibreglass resin would be chemically resistant to fuel, but then maybe it has a special coating on the inside. Regardless, aside from possibly needing a sheet metal rock-guard can anyone see what the problem would be in having our tanks made of fiberglass? The advantages of cost, and ease of fabrication are obvious.
I have seen fiberglass melt when in contact with fuel... There has to be some sort of coating on the inside... Prolonged contact of fibergalss and fuel would deff cause a..... minor catastrophic failure...
Yes I have a LineX spray in liner in my truck and I like it very much, but not everyone has access to spray in liners. I was merely offering an option, no need to slam on DIY'ers
I am not endorsing a Fiero fiberglass tank but a long time ago...
I'm getting in the way back machine here, but as I remember it - Ossa motorcycles had fiberglass tank, fenders and side plates. They even came with a fiberglass repair kit. So if you ran into a tree or something and cracked your tank or fender you could fix it on the spot.
[This message has been edited by Pappy (edited 03-17-2011).]
Joe, you got the design document on that? A CAD file would be superb if you had it handy.
Sorry no design documents as of yet. There is a file for the tank in the lambolounge link above. We used this file for rough measurements to see how far we could go in each direction. The only drawback is that tank requires modifying the frame of the car and making certain things work.
I doubt there will ever be a CAD file for this tank, Tony can draw up a sheet that he will use for cut sizes and he just welds them together. It is something he does for a living, not just a machine shop that will crank out these pieces for assembly. Each tank (if he goes forth with making them for purchase) will be hand made by him and should only take him a day or two to produce once he has a build plan.
How do you handle the potential for galvanic corrosion due to the electrochemically dissimilar metals in contact (aluminum tank contacting steel used in the car body, supports, and fasteners)? If you don't have the tank well grounded (i.e. insulated from the chassis) you run the chance of static buildup in the tank with a resultant spark, perhaps during fueling. If you do have the tank grounded, you have dissimilar metals in contact and something (the aluminum) will suffer, especially in the presence of impressed voltage which may occur from sensors, ground resistance, etc. Since aluminum tanks are uses in lots of vehicles, there must be a solution to the possible corrosion. How is it done?
Paul McKibben Norcross, GA
SS Ground straps and some penetrox should do the trick.
If you could make these with a bigger opening so people could run a larger or dual-fuel pumps, I think it would be interesting for the big-power people out there. Especially if you want to run E85.
------------------ '88 GT- 3800 Turbo 11.367@121.03mph FOR SALE GM Tuners
Not too sure of the fatige properties of aluminum are; if your buddy had a bending brake, he could cut his welding time in half and possible make a better tank w/ fewer welded seems...
Yeah, Tony has a very large brake, but very little of the tank *could* just be bent instead of pieces. He has tons of experience builiding tanks much bigger than this and I assume if he could have done it that way he would have, he more than knows what he is doing.
I called him up tonight to let him know the response this thread has gotten and that he needs to put a fire under getting things together to make these for sale. He is going to come up with a price once he figures out just how much labor would go into one of these tanks once he has a build sheet made. Immediately he could reproduce the tank I have it people want one with the capacity mine has, but requires some creativity to hold it up. When we both have time I have another Fiero with the tank removed so he can build one that is smaller in some dimensions and I can test fit it and modify until things fit right.
One thing to note though, this tank will be made in raw aluminum only, if you choose to coat it however you want, it will be up to you. We can make a tank that will fit as close to factory as possible but keep in mind it is a custom piece and not a direct drop in replacement. No matter how close we get to factory size the straps will need to be lengthened because of the provisions in the stock tank wont transfer to the new one.
As far as the hole for the sending unit, making a bigger hole would be no problem. We can also modify the placement of the fill tube and vent tube on the tank. My vent tube is as high as it could possibly go, a good 3 inches higher than stock. However, fuel expansion requires a place for fuel to go and if the tank is stark full and expands, it may cause problems so its up to you to tell us how high you think it should be.
Another thing to consider; aluminum may expand/contract more then a steel tank; making the position of the overflow that much more important...
The way I see it, if you used a brake to bend the aluminum (if aluminum can be bent to a 90 deg angle) to shape; it could be made out of two pieces. The bottom and sides could be bent into a U shape. The top and front/back could be bent into another U... Thus eliminating about 66% of his welding... Once you know the shape of the flat template, bend lines & angles, I would have to imagin it could be made in less then half the time. Also using alot less welding consumables...
also, why not have him make some aluminum mounting straps? either built-in to the tank or a seperate bolt-on piece?
Just tossing ideas out there. I think this could be very valuable for the fiero... Just gotta get it priced right for us cheap asses
Fibreglass works fine for fuel tanks. Epoxy is perhaps best, most composite homebuilt aircraft out there have integral tanks. Polyester and vinylester will also work, however. again, an inside coating of epoxy is preferred, but not required. Chris Craft used to install glass tanks from the late sixties on, they are still doing fine. I have some straight polyester tanks that I personally built 25 years ago still doing OK.
for baffling in the fuel tank in my friends race car we put wiffle balls, filled it to the top. stoped the fuel from sloshing back and forth. just a though. nice alum. tank. fuel cells have foam.
Very nice. Looks great and sounds like an improvement over the stock Fiero tank.
