Building a drop tank racer

Hello! 
 I dabble with cars and motorcycles and I've been thinking of building a drop tank racer for awhile now. I have some leads on a few tanks that are in a swamp on an afb. I hope they're still there as it's been a few years since I've been out there. I was just wondering what y'all thought the legality on grabbing one would be. I'd figure finders keepers would work as they're really just trash out there but i don't really know. Also just wondering if anyone had built a modern one recently and how you went about it. It's definitely a long term project that will be many years in the making. Any help or guidance would be great.

Thanks!

If they're on an air force base I would assume they are considered government property.  If you did pick one up, what are the guards going to say when you exit the base?

Not sure what legal weight the opinion of the board holds, but I say if you git it you got it and do a build thread.

Followed a build on Metal Meet years ago where the guy build the belly tank and the racer. 

I'd assume they're AFB property as well. You can find them relatively easily, if you dig around. I've been a part of a few. Working on one off and on for a friend of mine. OHV converted flatty. Going to run it at Bonneville and maybe some standing mile stuff is the plan.

What in particular are you looking to do? I'd start with getting the rule book for whomever you want to run with, and read it a few times. And go from there.  Packaging is key in these things...

In reply to b_mick :

I assume you don't know how to shape metal?   I would think that the risk of getting caught far outweighs any value.       
      Unless you can find a safe/legal way to acquire them I'd rather build my own belly tank.    A few sheets of Aluminum and a little bit of time with rollers would get you 80% there.  The rest you can do be eye  or•••• build a Buck.  It's easy to do that.   Take some poster board and fold it in 1/2 then draw out the shape you'd like. Cut it out and when you unfold it  both sides will be exactly the same .  

 Make  a fiberglass mold.    That would be the least expensive, fastest way to go fast on the salt.   Buy some styrofoam  lay it out, shape it.   Cover it in a cost of bondo, smooth it out.  Coat the bondo with a release agent like PVA ( you get that from the same shop that will sell you fiberglass cloth, resin and Gel coat.)  use cloth not Matt or you can use carbon fiber but that will be more expensive. 

Thanks for the responses. Kinda figured that's what y'all would think on the legality on grabbing one however I have heard of people grabbing ones out of the gulf. Wouldn't those still be gov property? I digress. If y'all know somewhere to buy one that'd be great cause I can't find one for sale through the usual routes. I'm really wanting to build one with some more modern stuff than an old flathead. I have a nice 351c laying around that I thought of doing. Im going back and fourth on a land speed car or making it more road course oriented or maybe doing something wild and making for the strip. I'm just wondering what trans y'all would suggest as I'd like to go mid engine. I've also thought on putting the motor up front and sitting atop the tail end of the trans (definitely what I'd do if I built it for the strip. I know an old zf like the ones that came in the gt40s and panteras would be good for mid engine but I don't have the budget to drop 20k or more on a trans so anything else would be good. I know the packing is gonna be key so do y'all think what I want to do is possible? Please give me ideas! 

There was a guy in Minnesota selling surplus drop tanks on FB Marketplace just a couple of weeks ago, IIRC.  I searched but could only find this and this. NMNA.

Have you tried Ebay?

There are a bunch of engines that can be had for very cheap money,  ( a few hundred) that you can use without taking apart.  Make 6-800 horsepower.  With the aide of an EBay turbocharger and E85 fuel. 
    If you go to UTube and click on Nivlac57  you'll see plenty of videos on various engines.  He compares the common LS with the Atlas 

   There is another U tube channel that helps you discover various engines besides those two .  Small block Chevy, V6's Big Block Chevy etc.   does dyno runs right out of the junkyards 

      The hard part is about the only cheap transmission that will stand up to that sort of  use is the GM Turbo 400. 
     If you are going land speed racing a longer car with the engine behind you is better for the salt and then you could use  the TH400. 
      The trick to the salt is not to use the ordinary engine.  While they are well known, they are also well used and thus to go a little bit faster requires all the expensive stuff  just to start and then you have to discover  that hidden horsepower someplace.  That gets brutally expensive.  
     Oh,  you can show up and just run.  See how fast you can go on whatever you can afford.

  But there are classes where the record was set a long time ago.  Typically the smaller engine classes. Where a modern 4 valve engine would have a easy time of setting a record.  There the trick isn't a belly tank but something more rain drop shape and as small as possible 

In reply to frenchyd :

Uhm... that's not true. In F/GL for instance... the displacement is from 123-183.9 cubic inches. In UNBLOWN gas the record is 229.989mph. 

In fact, the shallowest records are either the flathead 4 cylinder in the 150's, or J and K. Which is up to 30.99 cubic inches for K and 31-45.99 cubic inches for J. And those records are 181.xxx and 184.xxx iirc. Everything else is all up in the 200's. And beyond.

That 351 would slot into C. That record for unblown gas is 276.xxx by Ed Shadle. 

With Bonneville even if the car has ZERO chance of setting the record, it must be built to safety specs for the class record. Their playground, their rules. 

Going to fuel classes and blown classes, things get much faster. Especially blown fuel. There's no such thing as a shallow lakester record. 

What's the record for a 3 cylinder 2 stroke ......or even a e85 3 cylinder , 

might be something you could do well in ......

In reply to californiamilleghia :

It's all displacement based. So you can't just say a 3 cylinder. You have to go by cubic inch. 

There is also a few companies that make glass drop tanks. About a thousand bucks and done. And easier to modify if you can't shape sheet metal. 

http://classglassperformance.com/P-38%20Belly.html

But again, it all depends on what you want to do. Building for Bonneville also requires planning for the class as different classes have different wheel base requirements and such. That one up there was stretched to 111", to meet such requirements if it ever runs with a larger displacement engine. 

Also, if you are looking for a Pantera type transaxle I assume you want independent rear suspension.  Not that it can't be done, but it introduces a whole new ball of worms fitting that all into a tanker shell. They're narrow. Narrower than people realise.  The other thing to think about too is for road racing you might be limiting yourself severely, having an open wheeled setup like that. There's a lot of sanctioning bodies that don't mess with open wheel stuff on days when running sedans and the like on open track days.  Also, they aren't like a formula car...where there is enough to have their own classes to run. And even then guys sometimes rebody those to be fully faired in and no longer an open wheeled setup. Just more stuff to think about. 

Not trying to discourage you, but more telling you to kinda nail down what you are wanting out of it, first. 

And as a for instance if you built a 3 cylinder out of the ford Fiesta st... that's a 1.5L 3 cyl. So its  would put you into either H or G depending on exact cubic inches. H is from 62-92.99 and G is from 93-122.99. Again, depending on how many cubes..and im too lazy to look it up... but running it turbocharged in a lakester body is either gas class which is a 230 odd record in H and a 248 record in G. In blown gas. E85, methanol, etc. Bumps you to a fuel class.  So this was assuming pump gas, turbo 3 cylinder out of a Fiesta. Pretty steep. The trick is getting the stuff to hold together for 5 miles. And a return run. 

I'm not necessarily trying to build a full race or Bonneville legal ride, really more of a proof of concept on my first go round to go have some fun at my local tracks. I have a little experience with sheet metal but I'm honestly not confident enough to bend the tank from scratch and be happy with it so I'm definitely going to need to find a used tank. So we think a zf or equivalent would most likely be too wide. If I didn't go the transaxle route what could my other options be. I've heard of people shortening the torque tube from a vette and going that route for other styles of cars but I doubt that'd fit. I will say that I'm 100% going v8 (likely sbf as that's what I can build easily and cheaply). On the topic of going front engine how do y'all with more experience think that'd be. I thought maybe doing that and a narrowed solid axle for the back. Also what do y'all use for the front end. I dont currently have a tank in front of me so I'm just spitballing ideas. I'm going to start working a little cad once I find a tank and can get the dimensions. With the cad, has anyone made a model of one? 

Ask. Simply ask. Get in touch with someone of authority...and ask. They might be happy to see it gone. The worst they say is no.

Doug Elcomb races one..  Not a modern one though but this one races in vintage in Ontario asn apparently much further afield based on this article.

https://www.theglobeandmail.com/globe-drive/reviews/classics/racer-built-from-jet-fighters-fuel-tank/article1376150/ 

In reply to b_mick :

Again. It *all* depends. A setup for running bonneville is *completely* different than one for drag racing would be and that is completely different than one for road racing would be.  They have nothing in common except for all having 4 wheels. 

The lakesters for LSR tend to run a minimal amount of travel, if any, out back and a very minimal amount up front - typically with a ford straight axle. Usually lots of caster. Usually pretty stiffly sprung. Out back it's common for either a rigid rear or a sprung rear using rubber pucks as a spring and shocks only.  As all suspended wheels need shocks, by the rule book. 

This is why it's important to come up with a plan. It's all going to be one off. You'll have to make a frame that fits inside the shell and build off that. These tanks are literally just a skin. Also why I suggested the fibreglass one... there is a TON of work that needs to be done once you have a real one...removing the internal ribs and baffles. Coming up with and fabricating a mounting flange, stiffening the body, etc.  Repairing the rot (trust me, they all have rot, even the alloy ones have years worth of corrosion that needs to be fixed...and those usually are a steep pile of cash). Possibly stretching the body to meet wheel base requirements, for whatever you are building. And on and on. 

You can find dimensions of drop tanks on the net from aircraft restoration websites. Then model it yourself in CAD. P-38, p-51, F-104, F-86, etc are all commonly used. And all different dimensions AND shapes. So, again. It all depends on what your goals are and what you are doing.

I would start with asking yourself what your honest plan is for the car..and what your fabrication level is. As everything on these needs to be done from scratch. Can't buy anything out of a catalog or bolt stuff up from another model. 

If you want to road race..check with who you plan to run with and see if they would even let you on track with an open wheel drop tank before you do anything.   Drag racing is build to the NHRA book. Land speed. Build to their book. 

In reply to Appleseed :

I think that's the way to go however I know that they do not keep track of them whatsoever and treat them as trash. I used to go back there and hunt and you'd just be walking around and find a couple sittin. I figure it's better safe than in military prison so yeah 

Here's a P38. Dimensions are pretty accurate... but again there's a bunch of other tanks out there. 

In reply to GaryC83 :

Thanks for the insight! The more I think the more I'm leaning to do a land speed car for the first one just due to the simplicity. For those cars do you know the typical trans and diff selection that people go for. I guess with super limited travel in the rear you can get away with just going with a super short driveshaft or do you think I could do a transaxle. Just wondering if a transaxle has been used in one before and how it fit. My dad had a pantera for many years and I grew up seeing it in the garage before he auctioned it so I've always wanted to build a car with a sbf and zf transaxle 

In reply to b_mick :

It all depends on what class and how serious you are about the record and what driveline you are running. There are lakesters out there running Audi / VW engines & trans. Das Bullet comes to mind, iirc. Theyre up in the 200's I want to say.  There is also a ton of guys running high dollar quick change rear ends with air shifted liberty transmissions - up to 7 speeds. Also guys running stuff as simple as a th350 or th400 and a sbc and whatever rear end they had laying around.  It...just. depends. Budget. How serious you are about chasing the record. And on and on.

Just rememeber, get a rule book and build to the class. Different classes have different wheel base requirements, safety, etc and it's based on the record in that class. Not wether or not you are capable of actually setting it.  Even if your setup is only capable of doing 175, if the record is at 275, it will need to meet the safety requirements for that, as that is the class it runs in. 

Buy a book from the SCTA. 2023 isn't out yet i dont think, but will be shortly.  Then figure out what you want to do based on classes and work from there.  Trying to build a car and then find a class for it to fit in... is the goofy way to do it.  It'll be displacement base. Then a lakester. Then either blown or unblown, and either gas or fuel.  

I'm not trying to talk you out of anything, by far, just trying to get you to have realistic expectations going into it. Read up. Go over to the landspeed forums. Read the lakester build threads over there. Ask questions. Just be specific and don't ask a ton of super general nonspecific ones. Just get a plan, start laying it out and ask as you come across things. You'll get along nuch better over there that way. Everybody is super helpful, but won't do the legwork for you. If that makes sense. 

Edit. Now with link. 

https://www.landracing.com/

if you want to join the 200 mph club maybe it faster and cheaper to buy a finished car that has run 180-190mph and go from there , 

I know thats probably not the plan , but it gets you out on the Salt quicker......

PS ; There were a lot of fiberglass cars in the 1950s-60s that did 200 plus with Big Hemis and a blower......

Also, remember that WWII drop tanks are 80 years old, and were always meant to be discarded. They command a premium.

There are all different size drop tanks, depending on what they were used for. Obviously any tank will have to be big enough to accommodate the driver, engine, and frame and roll cage.  That has to be figured out first, before you know if you can run a V8 or have to resort to a Briggs and Stratton.  

b_mick said:

In reply to GaryC83 :

Thanks for the insight! The more I think the more I'm leaning to do a land speed car for the first one just due to the simplicity. For those cars do you know the typical trans and diff selection that people go for. I guess with super limited travel in the rear you can get away with just going with a super short driveshaft or do you think I could do a transaxle. Just wondering if a transaxle has been used in one before and how it fit. My dad had a pantera for many years and I grew up seeing it in the garage before he auctioned it so I've always wanted to build a car with a sbf and zf transaxle 

You can bolt the transmission right to the  rear end if you want.  No drive shaft required.  There are even parts available to do that.   The Turbo 400 transmission in Jaguars has a flange output  that will bolt up to a Dana  44 rear end.  
  While a Ford 9 inch is stronger.  Strength isn't the end all be all on salt due to the limited traction.  
  Plus the input on a Ford 9 inch is lower.    Depending on the tires used the oil pan could be dangerously close to the salt ( or actually in the salt)  Besides there are 2:88  limited slip  ratios available  for a Dana 44 

      Certain Audi Transaxle's can be adapted  to achieve the same goal as a ZF transaxles. It requires running them upside down.  But has been done.  Plus they are wonderfully stout and cheap.  
  More than a few cars run no suspension at all. It's rough on the driver and requires a complete nut and bolt check after every run.   But the salt is carefully graded flat.