Another belly tanker, QLD

See cars and bikes being built for the salt

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Rob
Posts: 1095
Joined: Wed Jul 06, 2005 5:30 pm
Location: Richmond, NSW. DLRA #888

Post by Rob »

It must be the thing to do, my sales were to be boats but they are still with us (for now). :wink:

Cheers,
Rob
I owe, I owe, so off to work I go.
sammj
Posts: 22
Joined: Wed Jun 09, 2010 10:30 am
Location: Darling Downs QLD

Post by sammj »

Got My DLRA membership and rule book today! Reading has begun. Still waiting on the SCTA book.

Have sorced a appropriate Kombi box and I am continuing to consider using a 12a Rotary for power as it's double the horse power and has a much higher max RPM. Also much more room for improvement through porting the motor etc. Plus I have a 12a lying around and a conversion kit (adaptor palte, flywheel etc) here already i can use.
Any one running rotaries on the salt at the moment??
Dr Goggles
Posts: 1315
Joined: Tue Jul 05, 2005 11:23 pm
Location: Right behind you Chief !

Scrotary

Post by Dr Goggles »

sammj wrote: Any one running rotaries on the salt at the moment??
Dave Partridge has an RX7 that goes ....you two can pit next to each other , there's plenty of space on the lake :wink: :lol: :lol: At least if you're running a rotary no-one will be hanging around to pester you , they'll be too scared that you might start it....

Na ,great choice I reckon, smaller size means better aero, more power is always usefull but more importantly than anything else is the revs. They want to tripleyour apparent capacity though so you'll be running in E Class, so don't expect anyfavours from those guys with that Commodore powered tank that runs in E class.
...few understand what I'm trying to do , but they vastly outnumber those who understand why..
sammj
Posts: 22
Joined: Wed Jun 09, 2010 10:30 am
Location: Darling Downs QLD

Post by sammj »

Triple!!!??
Thats a bit unfair :)
Who wrote that one, must of been a V8 person worried they would be left behind :lol: (ducking for cover)

The rotors hav two firing cycles per revolution not three. Even the QLD dept of transport only doubles the value i.e 12a regoed as 2.4lt.

I'm a bit sick as I do like a good brappin.
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BONES
Posts: 371
Joined: Wed Mar 15, 2006 4:28 pm
Location: Killara Sydney

another belly tanker

Post by BONES »

Hey Doc
don't talk too lould--- I have a mate with a norton rotary and I may be able to talk him into letting me use it.I was pitted next to you this year :lol:
cheers Bones
sammj
Posts: 22
Joined: Wed Jun 09, 2010 10:30 am
Location: Darling Downs QLD

Post by sammj »

I have been reading the rule book and mucking around with a speed calculator.
With 195/65 r15s .82 final gear and 3.875r&p at 8000 rpm it works out at 180mph
Does that seem feasible, obviously doesn't consider wind resistance, horsepower, wheel slip etc
Rob
Posts: 1095
Joined: Wed Jul 06, 2005 5:30 pm
Location: Richmond, NSW. DLRA #888

Post by Rob »

According to the net, that tyre has a diameter iof 635mm.

My math says 301.2km/h or 188.2mph allowing zero losses.

You should do better with 1:1 top gear and a final drive ratio change for similar overall gearing but more available rear wheel HP through not driving an overdrive gear set.

Cheers,
Rob
I owe, I owe, so off to work I go.
sammj
Posts: 22
Joined: Wed Jun 09, 2010 10:30 am
Location: Darling Downs QLD

Post by sammj »

Thanks Rob
I am limited by the ratios available for the VW box and I'm trying to figure the best combination of R&P and gears. All VW old school boxes have an overdrive 4th. Is driving an overdrive going to suck HP or are they generally weaker?
There are some aftermarket R&Ps for them but I don't want to get into that just yet.
Rob
Posts: 1095
Joined: Wed Jul 06, 2005 5:30 pm
Location: Richmond, NSW. DLRA #888

Post by Rob »

Driving a gearset rather than driving a 1:1 top gear is going to cost you hp. I can't comment on the amount as I don't know.

In my Soarer auto (as an example on strength), the auto overdrive becomes suspect at around 400 flywheel hp. Right now I can't afford the time nor the added cost to convert to manual and customise a diff to fit so I will run the auto, suffer the penalty of both auto and overdrive then change to manual the following year.

If you're budget building try to future proof things as far as planned updates go. It'll save you time and money in the long run. Remember too that you can vary final drive ratios using tyre choices but changing heights may affect your overall setup.

Don't stop asking questions. :D

Cheers,
Rob
I owe, I owe, so off to work I go.
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ROSS BROWN
Posts: 477
Joined: Thu Feb 18, 2010 6:43 pm
Location: COORPAROO BRISBANE

Whats happnen ?

Post by ROSS BROWN »

SAMMY J
Hows those drawings going ?

Cheers Ross
IT IS ALL A RACE AGAINST TIME.
TIME WAITS FOR NO ONE.

HOW FAST CAN YOU GO ?

S/UF 925
sammj
Posts: 22
Joined: Wed Jun 09, 2010 10:30 am
Location: Darling Downs QLD

Post by sammj »

No drawings so far :(
Checked out a few software programs but I think it will take longer to master them than build the car :roll: I wanted to use software so i could post some pics and get feed back but ill have to do it the old fashioned way. Build it, take a photo, post it, then hope i didn't do it the hard way.
I'm still waiting on the SCTA book which i want to cross reference first.

I have it all worked out in my head though if that counts.
sammj
Posts: 22
Joined: Wed Jun 09, 2010 10:30 am
Location: Darling Downs QLD

Post by sammj »

[img][img]http://i768.photobucket.com/albums/xx32 ... custom.jpg[/img][/img]

Here's another one I really like, old school.
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ROSS BROWN
Posts: 477
Joined: Thu Feb 18, 2010 6:43 pm
Location: COORPAROO BRISBANE

Option 2

Post by ROSS BROWN »

SAMMY J
Was given autocad 2000 a while ago , it took me 4 hours just to draw a wheel that was nothing more than Fred Flinstone could have drawn. :evil:
Gave it away to the next person that utterd the words autocad, and they did the same thing :D and I,d assumed that story just kept going. :?

DID it the old way, Sketches were drawn for the things that had turn or move up and down . and the main chassis was drawn & scaled onto a building plan size peice of paper.
Have since learnt to take photos of the different parts load them into "PAINT" and then start drawing frame work and bits around them.
Have got quite at it.
It will be an interesting build ,whatever you decide,looking forward to updates . 8)

Ross
IT IS ALL A RACE AGAINST TIME.
TIME WAITS FOR NO ONE.

HOW FAST CAN YOU GO ?

S/UF 925
sammj
Posts: 22
Joined: Wed Jun 09, 2010 10:30 am
Location: Darling Downs QLD

Post by sammj »

Does anyone know Ken Rhodes #108 user name on here or is there any info on his 4 cylinder belly tank?
Dr Goggles
Posts: 1315
Joined: Tue Jul 05, 2005 11:23 pm
Location: Right behind you Chief !

YEAH

Post by Dr Goggles »

That's a nice tank, if you want to build them "Ol Skool" Gow jobs you don't have to do any designing...bit like building a 32 roadster....choose a color, choose the wheels and hey presto you're ready to move onto something difficult like Lego.....

I'm just taking the piss. They're a pretty well established thing , T frame, flathead, old Ford diff........ My favorite ever tanks are that format but I don't feel inclined to fall over myself to build one.

The main gig with the CAD or whatever you choose to use is to plan the stance before you set anything in stone......find the relationship between the axles, what trackwidth and wheelbase....the biggest determinator we found was the roll cage, what you can fit in, that's legal...........even if you just use photos of the parts you intend to use and 'shop them together it'll be better than winging it.

Build a mock-up of the driving position, get as accurate an idea as possible of the length of the drive train......
...few understand what I'm trying to do , but they vastly outnumber those who understand why..
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