new to belllytank

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EAN09
Posts: 5
Joined: Fri Jun 24, 2011 12:52 pm

new to belllytank

Post by EAN09 » Tue Jun 28, 2011 10:55 am

hi fellas, I'm a new guy interested in building a belly tank over the next year or so, and while I have built single seater motorkana specials, and
formula vee over the last 20 years, my question is there a spec on chassie dimensions that must be met. noting this belly tank wil probably
be a mid engined 1600 through a vw gearbox. and any other advise to add to my homework file would be appreciated. ean

momec3
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Location: Cedar Grove Qld

Re: new to belllytank

Post by momec3 » Tue Jun 28, 2011 11:19 am

G'Day
Welcome aboard. Good to see another tank being built. If you get it done in the next year I'll buy you the first beer at the Lake, good luck. :wink:
Someone smarter than me will post a link to our new rule book which you can download for free. Its the bible. The basic tube dimensions and cage designs are there but the rest is totally up to you. There will be plenty of help available here so ask any question that comes to you.

Chris
Chris

EAN09
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Joined: Fri Jun 24, 2011 12:52 pm

Re: new to belllytank

Post by EAN09 » Tue Jun 28, 2011 11:47 am

cheers chris, I'll look out for it

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gennyshovel
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Re: new to belllytank

Post by gennyshovel » Tue Jun 28, 2011 1:47 pm

Try this link Ean,,and good luck with your upcoming addiction :wink:
http://www.dlra.org.au/docs/2012dlra-rulebook.pdf
Tiny
Tiny DLRA# 484
Postiebike Racing , created & funded by TwoBob Engineering

Dr Goggles
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Joined: Tue Jul 05, 2005 11:23 pm
Location: Right behind you Chief !

Re: new to belllytank

Post by Dr Goggles » Fri Jul 01, 2011 9:01 am

Hi Ean
Work out a rev/diff ratio/wheel size equation and compute what sort of speeds you are looking at for what you believe are safe revs for your motor.

For a 1600 you'd hope to be over 160mph I would reckon....

Tyre choices are limited as you will be looking for tall narrow ones with a high speed rating, they aren't much in demand for anything other than what we are doing so it's Goodyear Landspeeds or nowt.That means unless you have a fat wallet you will have 28inch dia. tyres or less.

The ratios for the VW transaxles are a bit limited aren't they?

I'm not trying to discourage you but this game is a bit like a venn diagram...... you need to find the intersection of what you can afford, with what you want and hopefully the intersection will equal fast....it doesn't for everybody. I'm prepared to bet you an amount you can nominate that unless you have a morbidly obese wallet and some very skilled employees that you won't be done in a year and I mean that in the nicest possible way.This is expensive and although there are plenty of people who are willing to offer advice and opinions it won't necessarily make the job easier.....in fact what you will notice is that each time you learn more your expectations rise......as I see it they rise in direct proportion . When you start 150mph sounds fast enough.Once you've built the car 200 won't be enough, you may never get there but it will be a stone in your shoe....that you can't get out.

I urge you to spend a year designing the body to be as good an aero shape as possible, you won't regret it. :wink:
...few understand what I'm trying to do , but they vastly outnumber those who understand why..

EAN09
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Joined: Fri Jun 24, 2011 12:52 pm

Re: new to belllytank

Post by EAN09 » Mon Jul 04, 2011 1:08 pm

thanks Doc, the more I think, the more I think I better come out to the lake next year and re think my thinking (oh my head hurts) ean

Dr Goggles
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Re: new to belllytank

Post by Dr Goggles » Mon Jul 04, 2011 2:04 pm

For starters I don't want to sound condescending .I posted the following on landracing.com as advice to another Aussie starting a build. It still rings true to me.

I've got a couple of suggestions and they are by no means aimed at you personally.I'm going to put them down line by line because I'm not(for once ) up for an essay right now.

It has been said many times here , everything has been thought of , lots of it done, some of it worked.....so find as much LSR history as you can...the good the bad and the ugly, the bold and the beautiful,look at 'em and read what they did.Some very clever people have been at this game, there have also been some mad ones and some very rich fools, learn from their experiences.

If you're going to be true to what you wanted when you started you first have to finish.This can be horribly expensive, if you bite off too much you'll have a half finished thing that has sent you broke.

This game is a battle between power and drag, you need to convince traction to be your friend. Power you can get at the shop,most people have more than enough.Drag is something your design will dictate and your design is prey to thousands of different factors.Keep it simple , have a reason for everything you do, not a hunch.

The rules. There are very specific minimum requirements related to safety, learn them off by heart and begin your design there. They dictate the smallest possible area you can sit in.

Learn the basics of aerodynamics, it's not likely you'll ever get to a wind tunnel so apply the knowns, the unknowns are bad science .

There are a lot of records up for grabs in the DLRA, but you're not the only person building something........have a really good look at the Budfab motorcycle streamliner, something along those lines is conceivable, aiming for 300 is a serious step for a self confessed newbie.

Go for it brother. If it wasn't for a shipload of naivete we would never have finished our car but that said I feel like the blind bloke who just walked across the freeway, I survived but I dunno what I was thinking when I started


It is important to build what you want. The issue though is how informed you are, as I mentioned in the above post it seems the more you learn in this game the more you expect.....so, you're into VW's....I can see some problems with aircooling, landspeed and air cooling are uncomfortable bedfellows.The important thing though is do what you want to do because that will get you through the times when everybody thinks you've lost it and you're starting to think they're right.

It worked for us.
...few understand what I'm trying to do , but they vastly outnumber those who understand why..

momec3
Posts: 763
Joined: Tue Mar 01, 2011 10:36 pm
Location: Cedar Grove Qld

Re: new to belllytank

Post by momec3 » Mon Jul 04, 2011 5:59 pm

Well said Doc
Could'nt agree more.
VW guys are a special breed, could give you bragging rights as the fastest VW motors but there are lots of more efficiant
1600cc engines out there.

My 2 bob
Chris
Chris

EAN09
Posts: 5
Joined: Fri Jun 24, 2011 12:52 pm

Re: new to belllytank

Post by EAN09 » Tue Jul 05, 2011 11:21 am

I dont plan on vedub motor, thinking ford 1600 through vw gearbox via adaptor plate, ala formula ford is my preferd idea to keep motor, gearbox and diff
in neat compact space and give more length room for me. ean

Dr Goggles
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Joined: Tue Jul 05, 2005 11:23 pm
Location: Right behind you Chief !

Re: new to belllytank

Post by Dr Goggles » Tue Jul 05, 2011 11:49 am

EAN09 wrote:I dont plan on vedub motor, thinking ford 1600 through vw gearbox via adaptor plate, ala formula ford is my preferd idea to keep motor, gearbox and diff
in neat compact space and give more length room for me. ean
Have you thought about the little Toyotas or a bike motor? With a bike motor you've got everything in a neat package and you get access to a wide range of gearing with chain drive that is difficult and expensive for diffs....
...few understand what I'm trying to do , but they vastly outnumber those who understand why..

EAN09
Posts: 5
Joined: Fri Jun 24, 2011 12:52 pm

Re: new to belllytank

Post by EAN09 » Tue Jul 05, 2011 12:23 pm

bike motor? thats an idea I could warm to, how small can you class a belly tank?

Dr Goggles
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Joined: Tue Jul 05, 2005 11:23 pm
Location: Right behind you Chief !

Re: new to belllytank

Post by Dr Goggles » Tue Jul 05, 2011 1:24 pm

EAN09 wrote:bike motor? thats an idea I could warm to, how small can you class a belly tank?
There's one running in the club with a 500 smoker in it(IIRC)....you could do worse than a CBR600, any of the 1litre superbike motors, or a Hyabusa will put you in 200 territory.

Trust me , there are a LOT of reasons why taking the bike motor path will save you grief and money. Performance wise they are ten times better bang for your buck. Running transverse gives you a lot more room, chain drive makes for cheap dial in gearing. You don't need to fab a scatter shield or a complicated gear shift...... They have BIG redlines....what they don't have is big torque, but they've got six speed boxes......

What you need to think about is whether you want to have a crack at 200 or whether you're going to fight in the welterweight classes(under 1 litre) where you can get away with cheaper tyres, lighter roll cage, less fire system etc, don't quote me on that.

Get two rule books, one for the house and one for the can. When you can comfortably quote from memory any relevant rulesfor lakester class you are ready to start building, if you are building and you need to come back here asking questions about rules you haven't read enough......the only reason I say that is you will find "sweet spots" in the rules that better suit what you are trying to do.

One word of etiquette, unless you start with a genuine bellytank or a fibreglass one you will be building a lakester, not a bellytank. A bellytank is a lakester,only some lakesters are bellytanks.........

Get thee out to the shed.
...few understand what I'm trying to do , but they vastly outnumber those who understand why..

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RGV
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Location: Adelaide Hills

Re: new to belllytank

Post by RGV » Tue Jul 05, 2011 7:56 pm

Hi Ean, ya dont need big HP to go fast, 125 cc 186 mph. :shock: http://www.youtube.com/watch?v=Vz_r_3yqqR4

Its a GP Honda RS125 i think so no ordinary motor, and a bike so has a advantage of only 2 wheels but goes to show what can be done with good aeros.

Good luck and have fun.

Last Minute Racing
DLRA #928

2010 MPS/G 250 118 MPH
2011 Washed Out
2012 Washed Out
2013 MPS/G 250 131 MPH (RECORD)
2014 MPS/G 250 140 MPH (RECORD)
2015 MPS/F 250 DNF
2016 MPS/F 250 114 MPH (RECORD)
2017 MPS/F 250 DNF

momec3
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Re: new to belllytank

Post by momec3 » Tue Jul 05, 2011 8:23 pm

If I were to live long enough to complete all my other projects a bike motor streamliner would be on the list. Horsepower per cube per dollar spent the bikes win every time.
Personally I think building a real belly tank is like building a ship in a bottle, should be attempted only if you are (or should be) commited. :lol:
Chris
Chris

Dr Goggles
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Re: new to belllytank

Post by Dr Goggles » Wed Jul 06, 2011 8:44 am

momec3 wrote:If I were to live long enough to complete all my other projects a bike motor streamliner would be on the list. Horsepower per cube per dollar spent the bikes win every time.
Personally I think building a real belly tank is like building a ship in a bottle, should be attempted only if you are (or should be) commited. :lol:
Chris
Can't say I have any reasonable basis to disagree with that. :wink:
...few understand what I'm trying to do , but they vastly outnumber those who understand why..

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