My Locost Build

My Locost Thoughts / Start

Edit - to skip backlog, scroll down till you see the bold text.

I've been doing research into my next project and thought I would share some of the progress with those on here. For those who know my past, this will make sense to you. For those who don't, I got out of the Subaru game after realizing how impractical it is to try and get 400+whp out of a 2.5L (well, mine was 2.63L) forced induction four cylinder. My original plan was to dump the STi for a C5 Z06, but I've found a better solution to this. It will be much, much faster, much, much lighter, and probably even more impractical than the Subaru :rofl:

Enter the Lotus 7 kit car (images)

My plan is this: 400whp / wtq, 1500 lbs (will most likely get up to the 1800 range, see below), sub $10k.

Yes, sub $10k.

These are the plans I'm using. This is the McSorley +442E design, designed to be slightly larger than the 'Book' frame to help accommodate....

An LS1. With a T56 6-speed gearbox. Mated to a 2003/04 Ford Mustang Cobra IRS setup (independent rear suspension). I plan on taking the design above and modifying it slightly. I'm using 1.25" square tubing for the main rails, 1" and 3/4" for the supports (where called in the plans). I also plan on running a full race cage, not just a rear hoop. The only other deviation will be 2" round tubing for the tranny tunnel, as during the couple months of research I've found that this will save elbows and have nicer ergonomics.

I plan on purchasing the metal in the next couple months, starting a jig and going from there. Quick budget numbers are below:

LS1 / T56 with wiring harness - $3500 (confirmed)
Cobra IRS (31 spline, includes diffs, axles, hubs, spindles, brakes, ebrake, suspension, brackets, etc. the entire setup) - $1500 (confirmed)
All metal and sheetmetal (less roll cage - will be professionally built) - $1000
Megasquirt ECU, electronics (gauges, switches, relays, lights, dash, blinkers, horn, etc) - $1500
Interior (seats, 5 point harnesses, fuel cell) - $1000
Miscellaneous (nose cone, fenders, odds / ends) - $500
Wheels and Tires - $1000

I think the last item may push me north of my $10k goal, but I've overestimated a lot of these items, including the two confirmed. I narrowed down the drivetrain options and called some local suppliers and I think I can get away with the entire drivetrain for around $4k, definitely sub $5k. This will be a slow process, so don't expect rapid change / updates, as I'm still researching and waiting for my basement option to open up so I have a place to fabricate.

If anybody's interested, you can email me at drew at jdbpartners dot com and I can share my google docs spreadsheet with you.

Tons of information can also be found at www.locostusa.com/forums

If anybody has any experience on these, please share...I'll be approaching this fresh, having never tinkered with any of the setups listed above. Should be fun...

Journal Begins

And so it starts...
Total money spent: $139.91
Total time spent (hrs): 20.5

Well, we started up today, got all of the metal cut and all of the angles sketched out so we can go back and hit it with the chop saw, hopefully next weekend. We ordered way too much metal, enough so that we probably have enough to construct a third frame...woops.

Frame Design:


Metal as delivered:


Metal cut for one car. I was really surprised at how little metal there is holding this thing together. Keep in mind, too, that these frames can be build using only 3/4" tubing...I don't see how it would stay together.


Mine and Nicad's piled for storage till we can get back and angle the pieces:


1/14/12
Got the angles cut on the upper and lower main rails, grinded them down so they're ready for welding. Aligned everything up, looking more and more like a car (ish)




1/19/12
More cutting...more angling...more grinding...

1/24/12
Finished cutting / grinding. Mocked up the compound angles to make the front nose cone, measurements and everything are right on. Hard to tell, but the two 2x4's are propping up the bottom, the other portion is on the floor. This is offset top to bottom to allow a little more clearance on the bottom of the car to fit the steering rack and components


2/5/12
Welded the bottom of the frame together. Came out pretty well, unfortunately my build table wasn't completely flat and i had to transfer to the floor. Fortunately, I noticed in time and once I welded the cross supports in, there's only about a half an inch of flex in the back corner (see picture 1). When you flip the frame over, it's perfectly flat on the corners and there's a small bit of flex on one joint in the middle. I'm storing the remaining metal on a pallet on top of the frame on the flat floor to help (hopefully) flatten it out. Keep in mind everything's only tacked, so I can still go back and grind them off and fix them later if needed.


2/12/12
Welded the top half of the frame assembly together. Overlapped the two together - BAM!! Shit's within 1/8" all the way around. I mean, I know it should be as I measured, remeasured, remeasured, one tack, remeasured, etc. so the dimensions were as close to perfect as possible, but with the oversized tubing, the dimensions don't exactly match the plans. However, everything lines up perfectly, so I'll put the final welds on the top and bottom half this week and then weld the two pieces together. Any questions, bring em on.











You can see how short the actual frame is

 

That looks like a really involved and fun project.
G/L

 

Who's welding? Nicad?

 

Nope, that would be me...well, everything but the roll cage. Getting some informal lessons from our manufacturing guys here at work, have an unlimited supply of scrap to learn with.

Need to learn how to do this shit anyway...probably shouldn't have tried starting with aluminum foil, lol

All of the welding will be 1.25" and 1" 16gauge square tubing. All of the body panels and what not are riveted in

 

Nice. I wanna learn to weld myself.

 

Whoa that looks like a cool project...GL

 

I am on the fence, but not necessarily to build or not.

I'll end up building a locost or a kit from RCR

this may be in my near future, hence my massive part out thread:



2100 lbs, LSx motor. think Zonda R levels of power/weight


in any event, I'll be building something. it's a good excuse to drink beer. the basement he is referring to is mine

drew: don't forget a good level and sturdy build table for tacking everything on.

 

I want a ride

 

it'll be cheap, i'm not using a metal table, going to stick with MDF. Read about all the pros and cons of each, not worth building a metal table.

plus, said basement has a sheet of mdf previously marked by my dog

 

too thin, but you can have it. don't want my speakers to smell like bitch

 

nah, i'll make it work...i thought it was 3/4"?

 

Loving both projects especially for their being very unique. Don't see either of those really ever around here.

 

steel tables don't spontaneously combust

 

I think it's a sheet of 1/4"

 

hrmm...i know 5x10 16gauge sheets are just over $40 at work, may need to invest in one of those...

 

http://www.thevintagecar.com/forums/showtopic.php?tid/5/post/new/#NEW

here's a nice rotisserie setup that won't break the bank. perfect for building a ladder frame, makes welding so much easier

 

Having built several gokarts from scratch including one with a race motoX engine/gearbox, at this scale, this would be a dream fabrication setup.

Sure would like to do one of these too. 7's are a long time favorite

 

What were you planning on using as a donor car? It's not necessary per se, but it makes life a heck of a lot simpler when you can pull your spindles, brakes, gauge cluster, chassis harness, etc out of one car to reuse as much as possible. If you can get your hands on a trashed MX-5, S13, or FC, it can save you a ton of trouble. The FC and S13 rear ends are nice in their ability to take abuse, both regularly putting up with modded LS1 power levels without a hiccup, not to mention a lot cheaper than the cobra IRS, and with better aftermarket support than the Cobra IRS. The only downside is that both oof those cars usually come in a 4.11-1 ratio rear. You could probably pick up a whole car for less than the Cobra rear, heck, when I'm done with my parts car S14, I may use it as a donor for my locost.

Love the locost though, and having driven a 442, they're a lot more comfortable than book frame cars. In for updates!

 

wasn't planning on using a donor, as I want a track ready beast I don't have to deal with. I was quoted $1300 for an 03/04 complete IRS assembly (31 spline) and sub-$1k for a 99-01 complete assembly (28 spline). This includes suspension, which I won't need so can possible sell off.

I looked for a donor, but there's no donor to fit my drivetrain needs...I'm essentially limited to 98-02 camaros and firebirds and C5 vettes (non-Z). Even with that, the wiring harnesses can be a pain in the ass, and there are tons of aftermarket harnesses to save me trouble (for the LSx motor). I'm going to use a nice race pedal box, aftermarket front brakes (big brake kit of some sort) and coilover suspension (not sure on rates yet, still reading into them...plus I don't know weights or geometries yet). The main things I'm lacking are steering rack and linkage, clutch and brake cylinders.

While my goal is to stay under $10k, that's just so I don't blow $30k on a "locost". Money's not really the key here. I'm more excited to learn to weld well, learn more about SBCs and dive deeper into suspension knowledge.

Oh, and I can't wait to see the looks on people's faces when I blast by them all the time (especially on track).

 

Theres no reason to buy the 03 and up irs assembly. The 99 irs will be plenty strong.

 

rereading your post, I know I don't want to do a miata based donor, but can the 240 and rx7 rears hold up to the heat / abuse of a full track day / weekend?

The hardest part about all of this is there's no good documentation on multiple builds showing the ups and downs of different decisions. A lot of my research is coming off Rob and Phil's V8 builds (former a 5.0 mustang, latter an LS1). They both used the 8.8" explorer rearends with two driver's side axles. However, both commented they needed to customize brackets and had to modify spindles / hubs.

 

call me mook - need to talk about cage options.

or, don't flake on friday night

 

Ill give you a ring tomorrow

 

They're awesome to drive. Take into account that a traditional "big brake" kit isn't really required with these super light cars. Larger rotors are of course always good for fighting brake fade, but you don't want so much braking power that you're constantly locking them up. What front spindles were you going to use? Ford options are good since you're planning on going without a donor. They've been using 5x114.3 for years, and have a huge selection of good factory brakes. Any SN95 Cobra brakes should be large enough to keep fade from being an issue, without too much lockup risk and heavy pedal from no booster, all while keeping costs down over a willwood/brembo/etc brake kit.

If you want a really good read on suspension knowledge, I recommend Engineer To Win.

http://www.themotorbookstore.com/entowiunraca.html

The book will leave you with more knowledge on metalurgy than you ever thought you'd know, and have an appreciation of how important it is in building a track car, not to mention a great explanation on the dynamics of suspension. A lot of good formulas in there that helped with a few of the builds I've assisted on.

SBC's are beautiful in their simplicity, all of your major gains with them are in your heads and cam. Your target power levels could be done on a "cam only" setup relatively easily. Can't wait to see your progress on this!

 

The 240 rears can with an high capacity aftermarket diff cover, they can handle being drifted all day long without failing. Though truth be told, a TT Z32 rear end is a fair bit larger, with a better selection of gear ratios, and tougher. It might be a better option if you take the mindset of overbuilding for reliability. The 240's use the R200 differential, N/A Z's and non GT-R Skylines did as well, whereas TT Z's and GT-R's used the R230, also available in Q45's. The nice thing about nissan is that their rear subframes and multilink setups lend themselves to hybrid and custom chassis easily, which can take a lot of the rear end suspension engineering headaches away for you. I should be doing some work on one of the 240's this weekend (wed-fri for me) and I can snap some pics of the rear suspension arms if you'd like, to see if it's something you might want to do for your car.

 

I'm still tossing it around, but I can't see it being worth it than paying <$1000 for the entire setup. Even if it's say, $500, is the savings worth the headaches of having to find all the additional pieces AND making them all work with each other?

Thanks for the posts, I was really hoping to get somebody with some knowledge on this subject around here

 

A 240 subframe would be the way to go.. strong, cheap and easy to find. You could get a whole setup for like $300 including lsd..
check out the 240atlanta.com classifieds.

 

bump it...

metal ordered today. I'll be cutting / tacking everything here at work over the next month or two and one of our shop guys offered to do all the final welds for me. Gonna be a lengthy project, but have to start some where...

 

this vs 914. should make it into a competition so I have more motivation to keep it/build it up

 

my build timeline is 2-3 years, lol

though, Nicad had me order double the metal, I'm thinking he may help push us along as well.

 

Well the current plan is nearly stock 914 with minimal costs, depending on how much I enjoy it.. I'll figure out if it's destined for race car or sale

 

I need to decide if I'm asking for a welder for christmas or a stock 914 engine. May start a thread of my own.


http://www.homedepot.com/webapp/wcs...productId=100670934&langId=-1&catalogId=10053
^^ Ask Justin what he thinks

 

yeah. double on the frame metal parts.

wire welders are fine as LONG as it isn't flux core. use some shielding gas and weld like a man

projects like this work better in pairs, IMO. I figure I can spare the play money to build something cool - plus drew probably needs the help

 

truth.

plus, buying used parts in double quantities offers discounts as well

 

Corvette Transaxle?

 

On my "Pro vs Con" list for building the porsche up.

 

Home Depot is fine for light switch cover plates and such but the last place to buy a welder. Buy a Miller/Hobart, even used they are by far the best. I have a vintage 1988 Miller Cricket and can still get parts for it. Can't do that with a Lincoln or anything less.

 

dom 1.5 xtr with e85 would put you over 400whp in an sti pretty easily. add a few more bucks and you can ditch the e85.. >.>

 

What the hell you talking about?

 

lol... I'm guessing he was replying to a question I asked in my journal.

I'm following this one as well and excited to see what you all come up with. I have some friends who build custom frames for articulated rock crawlers and it was always cool to watch the process from start to finish. Looking forward to some pics!

 

this

 

But aren't heavily modified Subaru's very unreliable? Anything over 380hp seems to always have issues or have to get a built block in a short mileage timeframe....right?

 

http://www.hobartwelders.com/products/wirefeed/handler140/
practically the same, yet $150 more. Really that worth it? Everything I've read is that the Blue/Red debate doesn't even matter for something on the lower end of the scale.

 

I would just like to jump in now and voice my prediction that this will never be completed. It will get to maybe the halfway point, though I doubt it will even get that far, before 07Ltd#767 and Nicad get bored with it and move on to a different project, never to return to this again.

 

Yea, but that price point makes it weld like the devil.

It's all marketing dude.

 

challenge accepted

 

Really excited to see what comes of these builds. Are they both going to be similar or both taking different directions?

 

drew wants to go small block chevy. I'm undecided. thinking turbocharged bike motor...