LocostUSA.com

Learning how to build Lotus Seven replicas...together!
It is currently Wed Sep 17, 2014 7:32 am

All times are UTC - 5 hours [ DST ]




Post new topic Reply to topic  [ 42 posts ]  Go to page 1, 2, 3  Next
Author Message
PostPosted: Wed Jan 23, 2013 4:32 pm 
Offline
User avatar

Joined: Sat Jul 29, 2006 9:10 pm
Posts: 2345
Location: Oregon, usually
A spot to discuss high efficiency Locost variants. The rest of LocostUSA is pretty much dedicated to high performance Locosts so I'd say this topic belongs in Building Non-traditionally.

One purpose of this topic is to point green readers (Mother Earth News readers in particular) here as an introduction to the Locost world. By "green" I don't mean wet-behind-the-ears, I mean people whose interest in building their own sports car includes the ecological advantages (e.g. recycling existing car parts, using vehicles sized appropriately to their tasks, and of course, reducing fuel consumption).

I'm not sure where to draw the line in the sand for "high efficiency" but I'd say twice the efficiency of the average passenger car is a fair target.

_________________
Locost builder and adventurer, and owner/operator of http://www.kineticvehicles.com


Top
 Profile  
 
PostPosted: Wed Jan 23, 2013 5:40 pm 
Offline
We are Slotus!
User avatar

Joined: Tue Oct 06, 2009 9:29 am
Posts: 5046
Location: Tallahassee, FL (The Center of the Known Universe)
Got yer logo right here, Jack-
Attachment:
kermit-it-aint-easy-being-green.gif
kermit-it-aint-easy-being-green.gif [ 35.66 KiB | Viewed 3923 times ]
Good idea for a sub-forum, too. I don't think my Slotus qualifies, but I might sit in the corner and listen, iffen y'all don't mind...

_________________
JD, father of Quinn, Son of a... Build Log
Quinn the Slotus:Ford 302 Powered, Mallock-Inspired, Tube Frame, Hillclimb Special
"Gonzo and friends: Last night must have been quite a night. Camelot moments, mechanical marvels, Rustoleum launches, flying squirrels, fru-fru tea cuppers, V8 envy, Ensure catch cans -- and it wasn't even a full moon." -- SeattleTom


Top
 Profile  
 
PostPosted: Wed Jan 23, 2013 10:55 pm 
Offline
User avatar

Joined: Sat Apr 26, 2008 6:06 pm
Posts: 2180
Location: Under the weather. (Seattle)
It might be less of a line in the sand and more of a DMZ. Consider an 'unmodified' Duratec 2.0L powered Locost. When put into a Locost possibly weighing under 1500lbs, this 140hp+ engine would probably fall noticeably within the high performance realm. But in a 2650lb Ford Focus with manual transmission, it turns a very reasonable ~2525rpm @65mph and can break over 40mpg in real world highway driving. Now in addition to freer breathing from the intake, header, and exhaust, mate it to a Ranger transmission backed by a tall aluminum 8.8 differential so that it turns ~2185rpm @65mph, and drop a sleek Lalo/Max body to it. How much could this combination improve the fuel economy over the already pretty economical Focus? Sure some would say it's a bit of a stretch, but might the end result also be considered high efficiency in addition to high performance? Or is that still more than likely outside of your goals for the purposes of this particular discussion?

_________________
-Justin

Also follow my build on blogspot, tumblr, or instagram and twitter (GarageOdyssey)


Top
 Profile  
 
PostPosted: Wed Jan 23, 2013 11:21 pm 
Offline

Joined: Wed Mar 28, 2012 5:29 pm
Posts: 34
Location: East Lansing, MI
I am in the collecting parts stage. I am trying to get a sort of compromise. I want light weight, good economy, moderate performance, and very high fun!!!
I am physically on the small side, 5'10" ,170lbs. So fitting in an original series 1 is no problem for me. As well as I prefer the aesthetics better of the original Lotus 7, over any of the book frames.
So, what am I going to use?
I will use MGB front spindles and brakes. An MG rear axle. MGA 15" steel wheels with 155ish tyres. For the power train, I am using a Suzuki G10 3 cylinder engine connected to a Suzuki Samurai 5-speed transmission. I have some head work done (the engine, not me), a lumpy cam, a header, and probably 3 Mikuni carbs. Guestimates are about 70-80 hp in a car weighing less than 1000lbs. That puts it in the original Series 1 Super 7 with the Coventry Climax engine. This was fast for it's day, although not so much today, but I think will give me that light weight and high fun!
I own a steel Hot Rod '33 Ford coupe with a SBC, 9" etc. It's fast and fun. I want to build something different though, hence the parts list for my Locost/Lotus.
Being used to heavy SBC engines and the also heavy drivetrain, I was amazed at the fact I could lift the whole G10 engine on my own!! The trans I can tuck under my arm!
So, the performance won't be earth shattering, but more spirited. The gas mileage should be good, but not in Jacks Lalo #s. The fun factor should be off the gauge!
I am aiming for a fastish, economical car that's fun. My idea of Green, I suppose!
Cheers,
Stewart.


Top
 Profile  
 
PostPosted: Thu Jan 24, 2013 1:09 am 
Offline
User avatar

Joined: Fri Dec 17, 2010 1:24 pm
Posts: 367
Location: Gainesville, Mo.
OK guys, how about this combination. A modified Haynes frame with Miata chassis parts, powered by a VW diesel mated to the afore mentioned Samurai 5-speed. Without the super-sipper Kubota engine, it won't have MAX's stratospheric mileage numbers, but the Rabbit powerplant should produce more than enough git-up-and-go to have a lot of fun. Now, you wrap this lightweight package in a slick, Lalo type body, and you should be able to register MPG numbers high enough to appeal to the tree hugger in all of us. Jack mentioned drawing a line in the sand at twice the efficiency of the average passenger car. Well, in an average passenger car, anything North of 30 MPG is pretty good. I see no reason that the Locost that I've described couldn't deliver 60 MPG or better, especially if we follow some of the lessons that Jack has taught us through MAX!

_________________
Mike - Read my story at http://twinlakesseven.blogspot.com/


Top
 Profile  
 
PostPosted: Thu Jan 24, 2013 7:24 am 
Offline

Joined: Wed Mar 28, 2012 5:29 pm
Posts: 34
Location: East Lansing, MI
For the "line in the sand", what are we using for the average MPG? I like to have goal to aim for, so what MPG would we consider good, and therefore, green.
Cheers,
Stewart.


Top
 Profile  
 
PostPosted: Thu Jan 24, 2013 9:27 am 
Offline

Joined: Tue Jun 15, 2010 8:29 am
Posts: 348
Location: Duxbury, MA USA
Since it will definitely have far less interior space and frontal area than a Toyota Pious (sic), I am suggesting that we should be looking at a minimum of 65 MPG.

_________________
Parts left out cost nothing and cause no problems!!


Top
 Profile  
 
PostPosted: Thu Jan 24, 2013 9:36 am 
Offline

Joined: Tue Jan 31, 2012 12:49 pm
Posts: 1022
Location: Raleigh-Durham NC
Jack --

How about a Euro-style "grill" badge (like we see on Mercedes for high mileage?) for locosts that get 50 mph? 75 mph? and of course, 100 mpg? Not sure how you'd certify those figures, but... at least it's a thought?


Top
 Profile  
 
PostPosted: Thu Jan 24, 2013 9:38 am 
Offline

Joined: Tue Jan 31, 2012 12:49 pm
Posts: 1022
Location: Raleigh-Durham NC
I recall that hydrostatic drive was bandied about years ago as a possible high mileage solution. Used by tractors world-wide, the basic premise is that a motor runs (more or less) at a constant speed and load as it pressurizes hydraulic fluid, which then would drive the motor.

At least that would be one helluva build. Bonus points if you have PTO shafts sticking out of the car I suppose, as well as a 3-point hitch?


Top
 Profile  
 
PostPosted: Thu Jan 24, 2013 10:08 am 
Offline

Joined: Tue Dec 20, 2011 10:19 pm
Posts: 135
I think a high efficiency sub-forum is an excellent idea!

There are many components to fuel efficiency, and I think most have been touched on in this thread. Having a light weight vehicle with a small engine turning slowly to minimize fuel usage are certainly 2 of the keys to fuel efficiency.

But aerodynamic drag is a big deal too, and needs to be emphasized. A body like Lalo is certainly the right direction. In my mind, Lalo's open cockpit is a potential source of drag, but compared to a 7 with all that stuff hanging out in the breeze, it's a streamliner.

I wonder what improvements could be made to Lalo to make it even more slippery?

I'm also curious as to how the Duratec / Ranger / 8.8 combo in a 7, would do mpg-wise compared to a stock Focus. I'd bet it'd be really close. Focus might even win compared to a 7 at typical highway speeds.

Hydrostatic drive is an interesting concept, but the all of the applications I've seen don't do all that well on an efficiency basis compared to a normal mechanical drive.

JustDreamin


Top
 Profile  
 
PostPosted: Thu Jan 24, 2013 10:12 am 
Offline

Joined: Tue Oct 19, 2010 11:57 am
Posts: 284
Location: Waterloo, WI
There's a forum called Hydraulic Innovations that does a lot of interesting things with hydraulic drives including some diesel motorcycles and a 2F1R trike (which seems to be stalled). http://www.hydraulicinnovations.com/for ... .php?t=452

_________________
-Keith


Top
 Profile  
 
PostPosted: Thu Jan 24, 2013 2:03 pm 
Offline

Joined: Mon Oct 19, 2009 9:36 pm
Posts: 1532
Location: meadview arizona
let me say now that my duratec 2.3 is thirsty, i don't get better than 40mpg on highway and i have a 3.3 rear end in the car, it will hit the 90mph speed limiter befor it hits 3000 rpm, the wind wall is noticeable.

the next thing is rubber band power as developed by DAF in holland in the sixties and used by volvo in europe in their small cars, keeps the engine at a moderate speed and vairies the drive belts through conical pullies.

_________________
drag racers lament

oh to go down to the strip again where the blacktop meets the sky
all i ask is a small block and some fuel to make her fly
with slicks a smokin pushrods pokin next round i'll get a bye

she's up on song the shift was strong in the finals to boot
it's back to the pits and take it to bits and don't forget the shute
the final round was good and sound so come on give me the loot


Top
 Profile  
 
PostPosted: Thu Jan 24, 2013 3:32 pm 
Offline

Joined: Tue Dec 20, 2011 10:19 pm
Posts: 135
A CVT (continously variable transmission) as John mentioned, is certainly a viable player.

They do have a couple of downsides. Power capability does have a limit. The rubber / kevlar belt will only take so much power before it either breaks or wears at a rate that isn't acceptable. Mechanical efficiency is also lower than your typical gear type transmission, but still should be higher than hydraulic (pump / hose / valve / motor losses) or electric drive (genset / controller / motor losses and potentially battery weight / losses).

Snowmobiles and many ATV's use that kind of hardware. I think they're still shifting the pulleys mechanically (weights, springs, etc). Having external control (computer / some type of electric actuator) of the shifting profile would be an excellent thing for performance (what the current applications usually require) and economy (something ATV's and snowmobiles don't really consider).

JustDreamin


Top
 Profile  
 
PostPosted: Fri Jan 25, 2013 9:43 am 
Offline
Automotive Encyclopedia
User avatar

Joined: Fri Dec 22, 2006 2:05 pm
Posts: 4710
The renault alpine M series and a210 raced and placed at Le Mans, using engines derived from a 43hp, 956cc inline 4. With a 1.3L version, they placed 9th and subsequent, behind the front running GT40 7.0L in 1966. Curb weight is less than 1500 lbs. The a110 was a successful rally car with similar power and weight, but without the full aero body.

Good aero allows decent performance with an engine that would otherwise be inadequate, so a traditional body can have similar mpg, but with greatly reduced performance.

With a body and curb weight like this, a stock metro 3 cylinder or festiva 1.3L 4 cylinder should accelerate to 60 in around 14 seconds in normal driving and be capable of very high speeds, depending on gearing.

I've found in normal driving, typical non-commerical traffic takes about 20 seconds to reach 60 mph.

Rear aero has a bigger piece of the drag pie than anything else.

These also had rear skirts (note the sharp edge of the fender) and note the radius of rear edge of the front fender opening. Compare this opening to VW 1L car (tandem seat, rear engined diesel) and you will see they are very similar. If it must be open without a skirt/cover, it should be radiused.


Attachments:
a210 side.jpg
a210 side.jpg [ 53.16 KiB | Viewed 3714 times ]
a210.jpg
a210.jpg [ 57.91 KiB | Viewed 3714 times ]
65 alpine lemans 1.jpg
65 alpine lemans 1.jpg [ 125.7 KiB | Viewed 3714 times ]
65 alpine lemans.jpg
65 alpine lemans.jpg [ 66.69 KiB | Viewed 3714 times ]

_________________
My reverse commuter trike build log: viewtopic.php?t=11384
Fitting glass and weatherstripping: viewtopic.php?f=23&t=6451
Growing various fruit trees, berry bushes, and wine grapes in zone 7b.
Top
 Profile  
 
PostPosted: Fri Jan 25, 2013 11:01 am 
Offline

Joined: Tue Jan 31, 2012 12:49 pm
Posts: 1022
Location: Raleigh-Durham NC
Miatav8,MstrASE,A&P,F wrote:
Good aero allows decent performance with an engine that would otherwise be inadequate, so a traditional body can have similar mpg, but with greatly reduced performance.


Yeah, at Indy, the Indycar people are running about 300hp less than on the street circuit I hear. And probably nearly half of what they ran back in the day -- I hear that 1000 hp wasn't uncommon for Pole Day, even in the Offy days. That is due to the steady progression of wind tunnel advances, along with a desire to keep speeds to a level that doesn't make insurance companies nervous.

And that also explains why this thread is important to people who are after performance -- Jack's quest to get 100 mph has lead to the Lola bodies, which will add a bunch of top end potential to our cars. Performance and efficiency are definitely related -- perhaps feuding, but related.


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 42 posts ]  Go to page 1, 2, 3  Next

All times are UTC - 5 hours [ DST ]


Who is online

Users browsing this forum: Exabot [Bot] and 3 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
POWERED_BY