LocostUSA.com

Learning how to build Lotus Seven replicas...together!
It is currently March 29, 2024, 6:29 am

All times are UTC - 5 hours [ DST ]




Post new topic Reply to topic  [ 73 posts ]  Go to page 1, 2, 3, 4, 5  Next
Author Message
PostPosted: September 19, 2011, 11:15 pm 
Offline

Joined: February 22, 2011, 4:14 pm
Posts: 50
Let me start with a short introduction. I'm Scott, and I live in Dallas.

Years ago, I owned a BPU Supra Turbo. It was awesome, and had about 450hp an 500 lb/ft of torque. The costs of operation were similarly staggering. While gas mileage was surprisingly good, tire life was quite poor. I was lucky to get 10k out of a set of rear tires. That wasn't because I was doing burnouts all the time (or at all). The high power levels, and the asymmetric tread pattern meant that I was going through tires that cost $150 each (those were the cheaper ones) with disturbing regularity. I also had some issues with my automatic (stupid I know) transmissions.

To make a long story short, I couldn't afford to keep the car, and I've missed it ever since. I've wanted to get the same excitement out of a more affordable package. For a while, I dreamed about spec Miata racing. Then, I actually sat in one. I'm 6'4, and at the time I was about 315 lbs. There was just no way that was happening.

Some years back, I read about the Locost. I was intrigued. It met my demands for affordability, both in construction and operation, and it sounded like a blast. I was pretty worried that I wouldn't fit in one, and then I found the 442 sized chassis. Oh, and I lost 75 lbs. Between the two, I'm pretty confident that I will fit.

Let me emphasize that I don't have any grand illusions about my engineering or fabricating prowess, so I really do welcome comments and suggestions throughout the process.

So, after a couple years of off and on research, I think I have settled on a plan. I want a little more power than the 1.8 Miata block, so I settled on the 2.3 duratec. I want an IRS setup, because I want a great handling car. I think the best source will be buying a wrecked Ford Ranger, and using it's engine and transmission, and perhaps using Miata stuff for the rest? Perhaps I'm better off using a Miata donor (I've heard the engine and transmission mate pretty easily) and buying the duratec separately.

In any case, I've started by building my build table.

I'm going to shoot for a metal framed table with an MDF surface.
Image

These are the legs for my table.

Image

I've drilled and threaded a hole into each foot so that I can level the table. My garage floor certainly isn't flat, but I'm hoping my table will be.

Image


Top
 Profile  
Reply with quote  
PostPosted: September 19, 2011, 11:38 pm 
Offline
User avatar

Joined: March 19, 2011, 10:22 am
Posts: 2386
Location: Holden, Alberta, Canada
Welcome aboard. Went for a ride in a Locost 7 w/2.3L out of a Mustang II that had a mild cam in it. What's that saying?? Oh yeah, I couldn't wipe that "sh*teating grin" off my face for a couple of days.

_________________
Perry

'If man built it, man can fix it'
"No one ever told me I couldn't do it."
"If you can't build it safe, don't build it."

Perry's Locost Super Che7enette Build
Perry's TBird Based 5.0L Super 7 L.S.O
Perry's S10 Super 7 The 3rd
Perry's 4th Build The Topolino 500 (Little Mouse) Altered
Perry's 5th Build the Super Slant 6 Super 7
Perry's Final Build the 1929 Mercedes Gazelle


Top
 Profile  
Reply with quote  
PostPosted: September 19, 2011, 11:49 pm 
Offline
Toyotaphobe
User avatar

Joined: April 5, 2008, 2:25 am
Posts: 4829
Location: Fort Worth, Texas
What part of town are you in? I'm awfully close by. Well if you call FW close.

_________________
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: September 19, 2011, 11:51 pm 
Offline
The voice of reason
User avatar

Joined: January 10, 2008, 4:47 pm
Posts: 7652
Location: Massachusetts
With that engine your power to weight will be a bit better then your supra. Might need just a bit of motor work for that, but nothing major. Considering the car will be lighter and lower and have less traction it will feel a great deal more exiting! Plenty to look forward too.

Your table may not be very strong or stiff, so you might need some bracing under those tubes. People put the engine and transmission etc. on the table sometimes while their working things out, so you will want it pretty strong. You don't have to, just saying. For that reason, if you brace the legs down low for shelves or whatever, make it able to let an engine crane slide under the lower braces or whatever.

Some folks use the ranger transmission from the 2.3 or 4.0. Getting a Miata does get you a good IRS, and suspension upright, steering rack etc....

Oh and Welcome! :cheers:

_________________
Marcus Barrow - Car9 an open design community supported sports car for home builders!
SketchUp collection for LocostUSA: "Dream it, Build it, Drive it!"
Car9 Roadster information - models, drawings, resources etc.


Top
 Profile  
Reply with quote  
PostPosted: September 20, 2011, 12:25 am 
Offline

Joined: February 22, 2011, 4:14 pm
Posts: 50
I'm in SW Dallas near Grand Prairie and Duncanville, so Ft. Worth isn't too far a drive for me.

My table isn't completed yet. I'm planning on putting a horizontal cross tube at the mid point, and then tying that in to the legs with diagonal braces. Do you think I need to add diagonals from the midpoint of my not yet installed center bar to the corner diagonals too?


Top
 Profile  
Reply with quote  
PostPosted: September 20, 2011, 7:10 am 
Offline
We are Slotus!
User avatar

Joined: October 6, 2009, 9:29 am
Posts: 7651
Location: Tallahassee, FL (The Center of the Known Universe)
Howdy Scott and welcome to the group!

Your plan for using Miata bits and a Ford 2.3 powertrain sounds realistic, I'm pretty sure somebody in here has done that kind of thing. If they haven't you still can! There's lots to read in the builder's forum, and even a non-engineer (like me!) can gather enough knowledge to build a solid chassis and put together the mechanical systems that make up a Locost. The main thing is to enjoy yourself...

Feel free to ask questions, there's a lotta information stored inside various heads around these parts.

Take care-
JD Kemp

_________________
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  
Reply with quote  
PostPosted: September 20, 2011, 8:28 am 
Offline

Joined: July 6, 2008, 11:15 am
Posts: 1047
Location: Cave Creek, AZ
Scott,

Welcome.

Your work table wont be strong enough in the middle with those 1" square tubes, they are not "tall" enough for the long distances between the vertical legs. You will need to put in strengthening ribs from leg to leg, either out of MDF glued and screwed to the bottom side of your top plate or with 20 gauge or thicker metal studs with the top plate screwed to them.

Diagonal braces in two planes will keep the whole thing from "scissoring" when you lean on it, but a shear plate made out of MDF on the back side will do the same. As stated earlier, put in a lower shelf to store misc stuff on under the top surface but make the supports for the shelf high enough off the ground so that you can get a "cherry picker" style of engine lift under it.

Tom

_________________
Sometimes, I'm as confused as a baby in a topless bar.

My short term memory is absolutely horrible and so is my short term memory.

https://www.youtube.com/watch?v=sG16m2e4O6I


Top
 Profile  
Reply with quote  
PostPosted: September 20, 2011, 9:05 am 
Offline

Joined: July 26, 2010, 10:37 am
Posts: 752
Location: Tennessee
Welcome. One bit of advise. Get the engine and transmission before completing the frame, otherwise, you will probably have to redo some of it.


Top
 Profile  
Reply with quote  
PostPosted: September 20, 2011, 8:09 pm 
Offline

Joined: February 28, 2009, 11:09 pm
Posts: 1307
Location: Connersville, Indiana
To clarify. The only Mazda trans that will bolt to the Ford Duratec are the ones for the 2.0 and the one used in the 2.3 Duratec equipped pickup. The 2.3 Ranger from 2002 up is the only Ford transmission that will bolt up. It may be possible to stuff the gearset from a 4.0 box into the 2.3 casting. The castings appear to be the same, but I don't know. The lure of the 4.0 gears is a closer ratio transmission.

Bill


Top
 Profile  
Reply with quote  
PostPosted: September 20, 2011, 9:03 pm 
Offline
Toyotaphobe
User avatar

Joined: April 5, 2008, 2:25 am
Posts: 4829
Location: Fort Worth, Texas
I travel to the GP, Mansfield area just about every week for business so one day after work we'll have to get together.

_________________
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: September 20, 2011, 11:28 pm 
Offline

Joined: February 22, 2011, 4:14 pm
Posts: 50
Here is my progress for today. Have no fear, there are more braces still to come.

Image


Top
 Profile  
Reply with quote  
PostPosted: September 28, 2011, 11:17 pm 
Offline

Joined: February 22, 2011, 4:14 pm
Posts: 50
More diagonal braces welded in.

Image


Top
 Profile  
Reply with quote  
PostPosted: September 29, 2011, 12:37 am 
Offline
User avatar

Joined: March 19, 2011, 10:22 am
Posts: 2386
Location: Holden, Alberta, Canada
Put some cross tubes where the lower part of the brace meets the uprights. Then you can slide in a piece of ply or mdf for a storage shelf, you won't regret it. My table is made of wood and I put upper cross pieces in every 12" then MDF on top of that. Like horizenjob says, you'll be putting weight on that table fitting the engine, trans, diff, rims, tires, blah, blah, blah, it all adds up.

_________________
Perry

'If man built it, man can fix it'
"No one ever told me I couldn't do it."
"If you can't build it safe, don't build it."

Perry's Locost Super Che7enette Build
Perry's TBird Based 5.0L Super 7 L.S.O
Perry's S10 Super 7 The 3rd
Perry's 4th Build The Topolino 500 (Little Mouse) Altered
Perry's 5th Build the Super Slant 6 Super 7
Perry's Final Build the 1929 Mercedes Gazelle


Top
 Profile  
Reply with quote  
PostPosted: September 29, 2011, 11:00 pm 
Offline

Joined: June 24, 2007, 6:04 pm
Posts: 1521
I agree, I think the table needs to be able to distribute the force of the cars weight evenly through several locations to ground.
There are too many unsupported points that will cause flex as weight is added to the table.
In my example below the weight is distributed to the four corners which are then in turn supported by the angled 1x1 inch tube.
This table easily supported my cars weight with engine and suspension in place and a minimum of tubing.
Basically cheap and simple.

Al

Image

Image

Image

_________________
Super Seven 3.4


Top
 Profile  
Reply with quote  
PostPosted: October 5, 2011, 10:35 am 
Offline
User avatar

Joined: October 24, 2008, 2:13 pm
Posts: 5326
Location: Carlsbad, California, USA
raceral wrote:
I agree, I think the table needs to be able to distribute the force of the cars weight evenly through several locations to ground.
There are too many unsupported points that will cause flex as weight is added to the table.
In my example below the weight is distributed to the four corners which are then in turn supported by the angled 1x1 inch tube.
This table easily supported my cars weight with engine and suspension in place and a minimum of tubing.
Basically cheap and simple.

Al



Another nice job, Al.

I don't mean to hijack this thread, but my next task is coming up with a build table design and making it, so this build table conversation is of keen interest to me. Besides keeping the table from flexing, I've been a little obsessed about two other issues:

1) How to make sure the plywood or MDF is truly flat for layout;

2) If I should bother to make sure the plywood/MDF top perfectly level, so I can use my electronic, Harbor Freight angle gauge to get indications of angles of members as I build the chassis.

If the table is on casters (a very nice idea) then #2 is out because my garage floor slopes about 2 degrees by design and it won't stay level once I move it. I'm not sure keeping it level is all that important, but it would be convenient. Being able to move the table could be very helpful.

Helping with #1 would be keeping the top rail of the table, the thing the plywood sets on, really flat and square. How did you ensure your table's top rail was really flat and square when you built it, Al? Or, did you just trust that the RHS tubing was "straight enough?"

Cheers,

Lonnie

_________________
Damn! That front slip angle is way too large and the Ackerman is just a muddle.

Build Log: viewtopic.php?f=35&t=5886


Top
 Profile  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 73 posts ]  Go to page 1, 2, 3, 4, 5  Next

All times are UTC - 5 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 33 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:  
cron
POWERED_BY