Daon151dh
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| posted on 4/6/07 at 02:55 PM |
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Chassis mods
Having just been presented with Ron Champions book at xmas, and currently finishing a mini resto. I have decided now is a good time to think about
the next project.
I want a hotrod 20's style pickup, having checked out the loco-blades on various websites the idea to combine this with my pickup idea was a no
brainer, power to weight ratio' are god.
I'd like to hear from anybody who has modified the basic Ron Champion chassis design.
My thoughts so far have been to make the driving position a bit more upright and move it forward. This makes room for the "load bed". The
space required to move the front bulkhaed forward I think could be provided by utilising a bike, or tuned quad bike powerplant.
Those are my thoughts, they revolve around the desire to keep the weight of the vehicle on or around the 600-750kg weight bracket. So, anybody who
has experience with building a locost with a bike engine and or modified the Ron Champion designed chassis I need to hear form you.
Regards
Neil
P.S. I've attached a quick sketch of what I'm talking about.
 
Rescued attachment pickup_sketch.jpg
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worX
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| posted on 4/6/07 at 03:23 PM |
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Hi there Neil,
looks like an interesting project you've got there!
I don't have any experience in modifying the book plans but you could check out the McSorley plans just for a bit of variation.
If you are going to build the car around 700Kilos, then it might be pushing it for an older blade engine (if thats what you were thinking of), but
there are plenty of other bike engines out there that will do fine!
all the best, and welcome to the forum!
Steve
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C10CoryM
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| posted on 4/6/07 at 04:07 PM |
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No input on the chassis w/o more details, but you may be able to use a front end front a "legends" race car if you build it small enough.
Little BECs with pre-war styling.
http://images.google.com/images?um=1&tab=wi&q=legends%20race%20car
Cheers.
"Our watchword evermore shall be: The Maple Leaf Forever!"
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speedyxjs
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| posted on 4/6/07 at 05:17 PM |
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Hi Neil,
There are plenty of bec (bike engined cars) on here to give you all the advice you need, and plenty of people have built Ron based cars with modified
chassis.
If i were you i would buy the new book (haynes roadster). It has plans for bec's. 
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Confused but excited.
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| posted on 4/6/07 at 05:18 PM |
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Finding 14" wide seats could be tricky.
Then you have the problem of getting your butt to fit the seat. 
Tell them about the bent treacle edges!
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locostv8
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| posted on 4/6/07 at 05:40 PM |
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I would think this would be a good project to create a middy using the entire eng/trans/suspension under/inside the bed.
http://wrangler.rutgers.edu/gallery2/v/7slotgrille/hssss/
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Daon151dh
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| posted on 4/6/07 at 09:03 PM |
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Thanks for the feedback, I was unaware of a new book ! That's a bonus. I terms of the bike engine, the 900cc blade would be a minimum spec.
Taking a build weight of 750kg the power to weight ratio is around 240bhp/ton.
Which is nice, however the 900 is less than 100lb/ft. I want something torquey, I had a discussion with a locoblade builder in Ulster called. My
thoughts then were to go down the quad bike route. But getting one at around 1000+cc isn't easy. Nor is tuning anything smaller.
Right now I'm thinking that the Suzuki 1300cc would be the best, it's torquey and disgustingly powerful.
I'll post more chassis at a later date once I check out the other stuff suggested, I've seen the Legends at knockhill before. By god
they're quick !!
Neil
P.S. Is it just me or is it normal to want a car with a power to weight ratio of around 300bhp/ton ?
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JoelP
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| posted on 4/6/07 at 09:21 PM |
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only a few thoughts on the subject. Blade engines ive heard of on rolling roads tend to produce around 120bhp, hence per tonne is only 150, not 240.
Once you add 2 people, you have one over worked engine.
If you can afford the gsxr1300 then all good, however, i cant stress enough how much becs need to be light to feel the benefit. 'Good'
becs are as low as 400kgs, 750 is ridiculous IMHO. You would be as well to use a cheap 200bhp car engine.
Imagine the comparison:
You spend 3k fitting a busa, have a 180bhp car that weights 750kgs.
Or you spend a few hundred on a 2 litre turbo or a v8, your choice. Weight would be around 850kgs.
180/0.75ton = 240
200/0.85ton = 235
Ie, nearly the same ratios for a fraction of the price, with an engine that is designed to move large weights.
Add 200kgs of human flesh:
180/0.95 = 190ish
200/1.05 = 198
suddenly the cec is faster.
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Peteff
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| posted on 5/6/07 at 09:03 AM |
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This is the book you really wanted then. If you want a hot rod, build one on the traditional lines or stick with the Mini.
Sticking all that suerstucture on a Locost type chassis is a non starter for aerodynamics, already bad enough. You'll need torque to drag it
along not rev the blocks off it all the time.
yours, Pete
I went into the RSPCA office the other day. It was so small you could hardly swing a cat in there.
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Daon151dh
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| posted on 5/6/07 at 10:48 AM |
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JoelP, a few words by way of reply.
Testing power output on a rolling road gives you a different reading from the flywheel. 900 blades are good for 160 at the flywheel. If the
application of the engine in a "bec" is showing only 120bhp at the wheels I'd be thinking something' right wrong. 25% power
loss through the transmission is excessive to say the least. Unless the engine is pumped of course.
Still and all, a car weighing in under a ton with 120bhp at the wheels is still going to be mighty quick my friend.
750kg is my maximum weight, and even at that, around 160ish at the flywheel will provide near enough 240 per ton. a 1999 model hayabusa chucks out
175 and I can get one of them for a lot less than 3k.
I can get a low mileage 900cc blade for £700 from a local scrappie, mildly twatted yes, but engine' still good.
Peteff, there's not actually a lot of superstructure being added to the basic design. The back end may look substantial but believe me an
aluminium tub with some decorative wooden framing will weigh next to bugger all. And the Studebaker-esque screen I'd say is likely to be a bit
more aerodynamic than the standard flat screen.
Cheers for the input guys, that book could be interesting from a styling point of view. But I think my bank manager would have kittens over me
driving something that does 12mpg, and tuning the bike engines is a bit cheaper and whole lot easier to do by yourself, so I'll stick to the
"bec" idea.
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Peteff
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| posted on 5/6/07 at 11:32 AM |
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But I think my bank manager would have kittens over me driving something that does 12mpg,
What do you think a Hayabusa or Blade engine is going to do in what you are proposing? I think you are in for a rude awakening 
[Edited on 5/6/07 by Peteff]
yours, Pete
I went into the RSPCA office the other day. It was so small you could hardly swing a cat in there.
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Daon151dh
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| posted on 5/6/07 at 11:55 AM |
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Peteff, check the figures these guys are quoting.....
http://www.locostbuilders.co.uk/viewthread.php?tid=68017&page=3
Now, are you honestly trying to say that even the 1300 Suzi engine is going to drink like a 2ltr turbo ford ? or a 4ltr rover v8 ?
Come on pal, be realistic.
[Edited on 5/6/07 by Daon151dh]
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Peteff
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| posted on 5/6/07 at 04:18 PM |
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Right pal.
We'll see when you've built it eh? If you think you are going to be in the twenties all the time you are sadly deluded unless you drive
like a trilby. I'll be happy to see it on the road but I'm having difficulty getting my head round the concept
[Edited on 5/6/07 by Peteff]
yours, Pete
I went into the RSPCA office the other day. It was so small you could hardly swing a cat in there.
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JoelP
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| posted on 5/6/07 at 05:47 PM |
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quote:
Originally posted by Daon151dh
Testing power output on a rolling road gives you a different reading from the flywheel. 900 blades are good for 160 at the flywheel. If the
application of the engine in a "bec" is showing only 120bhp at the wheels I'd be thinking something' right wrong. 25% power
loss through the transmission is excessive to say the least. Unless the engine is pumped of course.
rolling roads measure wheel bhp and estimate crank output. Of course you know this, but then you imply i dont so i thought id state the obvious 
I dont know which pub you were stood in when you heard that blades produce 160bhp, maybe the latest ones do (they are 1 litre now anyway) but the ones
up to ten years old are a hell of a lot less - bike transmission losses are around 8%, and might see 125 at the rear wheel. As a comparison, a 2003 r1
is only 154bhp at the crank new., and the 954 blade is 149 at the crank. Though i have no figures, im fairly sure that average car transmission losses
are around 20% anyway.
quote:
Still and all, a car weighing in under a ton with 120bhp at the wheels is still going to be mighty quick my friend.
Thats a matter of opinion, it might start off feeling healthy but to me, a BEC is a car that should drop most other vehicles on the road, certainly
all common cars and a selection of exotica too. My bec was about 120bhp and probably 475kgs empty (after id stripped everything spare out), and that
did prove fun - I hope this lives up to your expectations.
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gottabedone
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| posted on 5/6/07 at 06:27 PM |
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With a weight of 750kg we start to get into the HP against Torque arguement. With 120ish hp at the wheels, 750 kg plus two people, your bike engine
is always in the higher rev range in order to shift the weight. This is before you ask it to accelerate. Your fuel consumption will be more for the
same reason.
If you could shave 100+ kg off the weight - well you are into a different ball game!!
good luck - I'm not going to slate you for having a go but some of these guys really do know what they are talking about.
regards
Steve
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Daon151dh
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| posted on 6/6/07 at 11:20 AM |
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gottabedone, my error I suppose... the 2003 model 900cc blades I've looked at in scrappies are actually only 151bhp... still rather tasty mind
you. And I bet I could easily find another 10% without trying to hard.
In all honesty I can't see my weight getting to be 750kg, most of the build weights I've seen so far have hovered around 500kg. And
I'm not adding too much extra bodywork
As for fuel economy I would expect to see at worst a 25% decrease in economy. Now I just went and had a look at the economy figures for the blade
1000, suzi 1000 and the bmw 1200'. The suzi is the thirstiest at 39mpg average... then it's the blade at 41mpg. Both are chucking out over
160bhp. The best bit is the BMW which has 163bhp and an average mileage of 48mpg.
An economical locost based hotrod that just happens to be right quick is not infeasible. I tell you one other thing that could be a hoot, a replica
of something a Bugatti type 35 or one of the pre war alfa's !!
Check this out...
 
Rescued attachment pb12.jpg
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Daon151dh
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| posted on 6/6/07 at 11:21 AM |
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Bet you could build that at around 450-500kg or less
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JoelP
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| posted on 6/6/07 at 03:25 PM |
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if you built the hotrod pickup with lightweight as a priority, rather than ruggedness, you could achieve a quite low target. If the rear bed is for
looks only then simple corrugated ally sheet would suffice. The box frame itself would add little weight.
If this were my project id pick r1 or zx10, and aim for a weight of 550kgs, allowing maybe 50kgs of that for any extra bodywork, and 50kgs max in the
frame.
I'd also be tempted to pick a shorter diff than normal to spare clutch wear at the lights - maybe a 3.89 live axle?
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gottabedone
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| posted on 6/6/07 at 03:47 PM |
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Still sounds cool, a sort of retro Chevy Stepside.
[img] http://www.locostbuilders.co.uk/photos.php?action=showphoto&photo=stepside.jpg[/img]
You wouldn't have much weight in the rear with the back being mostly for show
regards
Steve
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gottabedone
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| posted on 6/6/07 at 03:52 PM |
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Blx! bloody images mad:- it's in my foty's archive
Steve
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Daon151dh
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| posted on 11/6/07 at 07:35 PM |
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Guys,
The back end will be purely for show, I reckon there will be just enough room for the spare wheel, jack etc and a small storage space. And the fuel
tank over the axle, just behind the cab bulkhead.
In terms of construction of the back, I was thinking that a box made of marine ply with a skin of thin ally sheet. The load bed will not be open
either. As somebody was thinking it is just for show, so there will be a lid made of ply with an ally skin.
The thoughts behind the front screen come from various Chevy, Studebaker et al vehicles. Also, thinking exotic here, the Bugatti Atlantique.
Some smart cookie had a batman moment earlier in this topic.... he suggested a mid engine.
There's a mob down south who do a kit for mini'. essentially it's a frame for a blade or suzi engine. This frame also holds all
the suspension pickups and a quaife diff that has a solenoid operated reverse mechanism.
This could be an option, this is their website... it's fecking demented !!!!
http://www.zcars.org.uk/mini/index.htm
£5200 for the full kit, I'll need to see if I could just get the frame, suspension and brakes.
Food for thought.
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physician
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| posted on 18/6/07 at 04:10 PM |
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that is quit an interesting edsign you got here. look great tome
red wheels and white walls would set it up great.
if i can introduced my 2 cents, since you'll have a smaller that the already tight passenger compartment, i think that a mid engine would be
better, since it will give you some width you'll probably need.
a bike engine can be fit in the rear or maybe a subaru engine if the shaft output is close to the the front of the engine, would have to check this (
i can get you the measuement, since my friend have an sti in his garage)
the later idea i have may not be the ceapest, but it is great, an harley vtein in the front with a flipped vw beetle in the rear ( or a porsche 914)
it even gives you the reverse gear. and take verry little space in the front.
you can search for twin tech to see what drive train i mean
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physician
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| posted on 18/6/07 at 04:14 PM |
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here is there site
http://www.twintechcars.com/
sure, it can be costly, and notso fast.. but certainly diferent
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