LocostUSA.com

Learning how to build Lotus Seven replicas...together!
It is currently April 28, 2024, 12:21 am

All times are UTC - 5 hours [ DST ]




Post new topic Reply to topic  [ 38 posts ]  Go to page 1, 2, 3  Next
Author Message
PostPosted: May 22, 2009, 5:38 pm 
Offline

Joined: August 12, 2007, 9:05 am
Posts: 112
Hello all, I am ready to build another trike (earlier ones can be found at tshtrikes.com )

so, here is what I want to build, 2 seat, side by side, very light electric / diesel hybrid.

the "guts" of the car would be carried in a 8" high "box" of 1" square with a roll hoop and dash hoop of 1 1/4 steel

Jack at one point suggested equal length arms, and I would entertain that, the "mission" for the trike will be mostly about super high mpg, but the electric motor I have chosen will certainly allow high speed (115 pounds of torque) so I would need to get it right as far as geometry.

oh by the way, I would happy to pay for some help with this, Pook, will you REALLY fab for food? :-)


Top
 Profile  
Reply with quote  
PostPosted: May 22, 2009, 11:15 pm 
Offline
User avatar

Joined: November 12, 2008, 6:29 am
Posts: 3567
Why not use a VW Beetle front end? Available in aluminium and in various disguises.


Top
 Profile  
Reply with quote  
PostPosted: May 24, 2009, 8:03 am 
Offline
Automotive Encyclopedia
User avatar

Joined: December 22, 2006, 2:05 pm
Posts: 8045
No need to reinvent the wheel.

Use an old 80s VW Rabbit Diesel for the fwd suspension, steering, brakes, etc.

Struts are not a downside when under hard cornering the inside wheel is going to come up anyway. Strut systems are lighter weight too.

Use tandem seating for a longer wheelbase (better handling, better aero, and less porposing).

Mount your electric motor behind the passenger with the swingarm pivot on the same axis as the motors rotor or the transmissions output shaft (if so equipped). There will be some drag from the electric motor if there is no clutch. I'd consider a centrifugal on the motor rotor.

Place the batteries on each side of the driver starting just behind the front wheels.

Use the electrics for acceleration and the diesel for cruising speed.

No headers. More power equals more BTU and fuel burned.

Since it would be expensive to have custom gears made and you will have excess power with the stock rabbit gearing, use larger diameter wheels/tires to decrease power/rpm. Keep the tires as narrow as possible. Wider tires hurt mpg.

I think you will find that going with just a diesel rabbit and no electric power will be better overall. Diesels have no throttle plate so fuel burned when stopped or moving slowly is minimal. The electrics will add a lot of cost, weight, and complexity.

_________________
Miata UBJ: ES-2074R('70s maz pickup)
Ford IFS viewtopic.php?f=5&t=13225&p=134742
Simple Spring select viewtopic.php?f=5&t=11815
LxWxHt
360LA 442E: 134.5x46x15
Lotus7:115x39x7.25
Tiger Avon:114x40x13.3-12.6
Champion/Book:114x42x11
Gibbs/Haynes:122x42x14
VoDou:113x44x14
McSorley 442:122x46x14
Collins 241:127x46x12


Top
 Profile  
Reply with quote  
PostPosted: May 24, 2009, 10:58 am 
Offline

Joined: August 12, 2007, 9:05 am
Posts: 112
Weird thing is I happen to have a diesel rabbit engine and suspension laying around. (as well as a geo metro xfi motor and trans)

I do want to build the hybrid though, the idea of an "electric hotrod" that also happens to get 200 mpg is intriguing. (I come to that figure by calculating the 10hp diesels claimed fuel consumption of 3 hours to the gallon and factoring the 80 to 100 miles the electric drive train will bring and applying a lot of hoping) I can almost guarantee that in practice the diesel will burn more then claimed, but on a "tank" for a normal car,say 400 miles, I beleive it would be an impressive number.

I am also drawn to a low slung car, I just cant seem to make the terms "front wheel drive" and "truly low slung" work together in the hand that wields the design pen, plus the overall weight with that vw diesel will be really high, I beleive the motor / trans alone is like 450.

Ok, quick unrelated story... I fly untralights (those "flying lawnchairs") and in that sport, we refer to anything heavier then a piper cub as a "heavy" like most pilots refer to 747's lol.

The motor and batteries, expensive I know. so were on the same page, here are the costs / weights.. ac-31 drive motor and inverter 3900, 90ah of lithium polymer batteries (about 80 to 100mi of range) for a 96v system about $3300 plus wires should be about 300 pounds for everything. the diesel motor will add about 100 lbs

with all that low end torque, over 100 ft pounds, as long as the car is light, under 850 empty, it should be impressive off the line.

Cheapracer, I hear ya on the v-dub beam, I am one of those guys that said "hey, its 70 year old tech, how good can it be" then after a conversation with Chuck Beck last year, he excused himself and went in his 550 spyder recreation and trounced an "evo" on the road course at Carlisle.

And Ive been looking hard at the weight of the vw beam with disc brakes (110 lbs including steering box and tie rods but not wheels and tires) not too bad and its like 95% tweaked right out of the box)

So vw beam (in aluminum) it is.

I can carry the batteries low in 2 "rows" 1 just ahead of the beam and one under legs just past the steering tie rods

Ok Tandem seating, lots of mixed feelings there, my first attempt (at tshtrikes.com under "diesel hybrid" ) had tandem seating, and it got long, and heavy, plus there is the problem of my principal investor (wife) wanting to have a conversation with me when driving :-)

I have a sneaking suspicion that side by side will do better in the plans / roller marketplace as well if this thing does what I want it to do.

Using the electrics primarily for acceleration, and diesel for cruising, I totally agree :-)

The measurements I am coming up with early in the process are 85" wheelbase, overall width at outsides of front tires 55", width at shoulders of cabin 44" overall height of main body 38" height at rear "wing" (roll hoop, that houses a wing that also doubles as a brake light / directional / liscence plate mount) 45" Overall length 120"

If only I was a 3d modeling kind of guy, I would post a drawing, but alas, my design is limited to paper and pencil, Id love to post a drawing.


Top
 Profile  
Reply with quote  
PostPosted: May 24, 2009, 1:27 pm 
Offline
Automotive Encyclopedia
User avatar

Joined: December 22, 2006, 2:05 pm
Posts: 8045
Keep it 14 CFR 103 legal. You never know when the Feds will come knocking. A ballistic parachute is worth every ounce of weight. IMHO, every plane should have one.

Tandem allows the driver to hear every word the passenger says but the passenger doesn't hear the driver, so it may work out depending on who drives. :lol:

The windscreen would start at the top center of the wheel arc. The hood forward of the screen matches the screen angle then forms another arc (think "Minority Report" Lexus with a little more front overhang). The driver sits about a foot further back than normal and practically on the floor, like with a seven.

You can build with an engine that has barely enough power to maintain cruise but how will you charge the system if it is used to maintain on hills, pass, and accel and still have adequate performance? The Insight guys have been toying with different programs based on a specific range or power level. They've noted large performance decreases when it came time to recharge. Thats fine if you have arrived though; just plug in for a few hours.


VW built a side-by-side fwd trike concept called the scooter in 1986. Looks pretty good to me.


You do not have the required permissions to view the files attached to this post.

_________________
Miata UBJ: ES-2074R('70s maz pickup)
Ford IFS viewtopic.php?f=5&t=13225&p=134742
Simple Spring select viewtopic.php?f=5&t=11815
LxWxHt
360LA 442E: 134.5x46x15
Lotus7:115x39x7.25
Tiger Avon:114x40x13.3-12.6
Champion/Book:114x42x11
Gibbs/Haynes:122x42x14
VoDou:113x44x14
McSorley 442:122x46x14
Collins 241:127x46x12


Top
 Profile  
Reply with quote  
PostPosted: May 25, 2009, 12:12 pm 
Offline
User avatar

Joined: November 12, 2008, 6:29 am
Posts: 3567
todayican wrote:
Cheapracer, I hear ya on the v-dub beam, I am one of those guys that said "hey, its 70 year old tech, how good can it be" then after a conversation with Chuck Beck last year, he excused himself and went in his 550 spyder recreation and trounced an "evo" on the road course at Carlisle.

And Ive been looking hard at the weight of the vw beam with disc brakes (110 lbs including steering box and tie rods but not wheels and tires) not too bad and its like 95% tweaked right out of the box)

So vw beam (in Aluminium) it is.

.


You can cut weight I think, a cut down rack rather than a steering box should help a bit. Is the ball joint or king pin lighter? Oh I just saw "disc brakes", meaning ball joints?


Top
 Profile  
Reply with quote  
PostPosted: May 26, 2009, 4:02 pm 
Offline

Joined: March 26, 2008, 5:05 pm
Posts: 45
Location: SoCal
todayican wrote:
Ok Tandem seating, lots of mixed feelings there, my first attempt (at tshtrikes.com under "diesel hybrid" ) had tandem seating, and it got long, and heavy, plus there is the problem of my principal investor (wife) wanting to have a conversation with me when driving :-)

I have a sneaking suspicion that side by side will do better in the plans / roller marketplace as well if this thing does what I want it to do.

I want to build a reverse trike with tandem seating. I like the symmetry. My wife would like side by side seating so we could share the experience more. Since I'm likely to be in it alone much more than with her, I'm planning on tandem, but I do agree that side by side is probably more marketable.


Top
 Profile  
Reply with quote  
PostPosted: May 26, 2009, 10:46 pm 
Offline

Joined: August 12, 2007, 9:05 am
Posts: 112
Ok, now I am all spun around design wise again.
I saw this site http://www.peterdmotorsports.com/index.html

These cars run the same weight as I am looking to do, great looking aluminum spindle, brakes etc for what I want to do. the entire arms, rack spindles hubs brakes etc is 56lb

I would need the arms to be a little shorter and the rails a little wider though.

Being that I am hopeless at suspension design, could anyone take a stab at a design.

Here is what I can say about the design so far.

I want the forward part of the frame to be 28" wide front and back , top and bottom (outside) / 8" high (outside) throughout and 34" long

(I want the entire inside of the "box" to house the batteries for the electric drive)

I can have the hubs from the site above made with the steering arms at the top front and ideally place the rack on top of the "box"

Any input? I would be eternally grateful.
Tom


Top
 Profile  
Reply with quote  
PostPosted: May 26, 2009, 10:52 pm 
Offline
Toyotaphobe
User avatar

Joined: April 5, 2008, 2:25 am
Posts: 4829
Location: Fort Worth, Texas
Adjustable Clamps holding the upper suspension pieces on, how interesting.

_________________
mobilito ergo sum
I drive therefore I am

I can explain it to you,
but I can't understand it for you.


Top
 Profile  
Reply with quote  
PostPosted: May 26, 2009, 10:53 pm 
Offline

Joined: August 12, 2007, 9:05 am
Posts: 112
By the way Miatav8,MstrASE,A&P,F, Cool on the UL knowledge, and Excellent catch on the VW scooter! (I thought I had ferreted out all the reverse trikes) lol


Top
 Profile  
Reply with quote  
PostPosted: May 27, 2009, 1:27 am 
Offline
User avatar

Joined: November 12, 2008, 6:29 am
Posts: 3567
carguy123 wrote:
Adjustable Clamps holding the upper suspension pieces on, how interesting.


Makes for adjustable camber gains and caster gains which you need to change during changing conditions through the day/night at a speedway track.


Top
 Profile  
Reply with quote  
PostPosted: May 27, 2009, 11:16 am 
Offline
Toyotaphobe
User avatar

Joined: April 5, 2008, 2:25 am
Posts: 4829
Location: Fort Worth, Texas
And I guess since it only has to hold for 1-2 races it doesn't matter long run whether it works loose or not.

_________________
mobilito ergo sum
I drive therefore I am

I can explain it to you,
but I can't understand it for you.


Top
 Profile  
Reply with quote  
PostPosted: May 27, 2009, 1:06 pm 
Offline
Automotive Encyclopedia
User avatar

Joined: December 22, 2006, 2:05 pm
Posts: 8045
If you don't want to design your own suspension and it is going to be rwd, why not use the vw beam? It may only be 56 lbs but it will cost a lot more than 56 pounds.

I think I've posted those scooter pics before but not recently.

The original disk brake vw spindles have balljoints.

The adjustable mounts are typical and everybody checks every not and bolt before a race right? :wink:

_________________
Miata UBJ: ES-2074R('70s maz pickup)
Ford IFS viewtopic.php?f=5&t=13225&p=134742
Simple Spring select viewtopic.php?f=5&t=11815
LxWxHt
360LA 442E: 134.5x46x15
Lotus7:115x39x7.25
Tiger Avon:114x40x13.3-12.6
Champion/Book:114x42x11
Gibbs/Haynes:122x42x14
VoDou:113x44x14
McSorley 442:122x46x14
Collins 241:127x46x12


Top
 Profile  
Reply with quote  
PostPosted: May 27, 2009, 1:32 pm 
Offline

Joined: August 12, 2007, 9:05 am
Posts: 112
Actually miatav8 the costs are really similar.

Ive been talking to some people about the costs of a vw beam with new or remanufactured parts, it approaches 1k for everything.

about the same for the components from the company previously mentioned, and were talking a hundred pounds less.

Im going to keep up the search for now for an accomplice on this front end design.


Top
 Profile  
Reply with quote  
PostPosted: May 27, 2009, 1:41 pm 
Offline
User avatar

Joined: November 12, 2008, 6:29 am
Posts: 3567
I suggest you also scour this website....

http://store.600racing.com/site/index.cfm


Top
 Profile  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 38 posts ]  Go to page 1, 2, 3  Next

All times are UTC - 5 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 6 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

Jump to:  
POWERED_BY