Another simple home built race car idea - Transfers FWD running gear in single seater        

Following on from Eric’s thread on Clubman’s/D-Mod ‘7’/Mallock thread here’s another type of project I’ve put way too much time into thinking about.  For those who didn’t like so many pics in that thread, tune out, you’ll hate this one.

First history.  In the ‘good old days’ of the 70’s and 80’s the path to F1 was FF1600 – FF2000 – F3 – then if you were food enough (Senna/Brundle etc.) straight to F1, if not then F2 later F3000 before F1.  The trouble was even by the mid 80’s FF1600 budgets were getting massive (relative to the time) and the top teams had highly suspect engines, team manager, mechanic and chief mechanic (now they would be called a Race Engineer).  Brand Hatch leisure, no surprise the owners of the Brands Hatch circuit as well as several others circuits (Snetterton, Cadwell and at least one other I don’t recall right now) was looking for a cheaper alternative to FF1600 cars for their race school and as a cheaper first step on the ladder.  Also as a side note, it was Brands hatch in the 60’s that invented FF1600 by putting street tires and a stock Escort ‘sport’ engine in an F3 car for their race school.

BHL worked with famed racecar manufacture Van Diemen to come up with a cheap, simple one-make formula for their school and a race series.  The concept was pure genius.  The car was basically patterned after the front half of a basic FF1600 with outboard suspension (no rockers or pushrods) with an Escort XR3 transverse engine and transmission behind the driver.  Again, the rear suspension was all outboard for cost and simplicity.  The engines were dry sumped for longevity on track, but other than that they were sealed units breathing though the standard downdraft carb with an angled spacer to keep it vertical as the engine and trans were rotated forward for a lower CofG and polar moment.  The layout was very similar to Alan Staniforths line of ‘Terrapin’ hillclimb cars as detailed in his original book ‘High Speed, low cost’ and also referred to many times in his classic ‘Race and Rally car Source book’.  Best of all they had circa 100hp and weighed less than 900lb’s (maybe lighter, I’m working from memory here) and they sold brand new, ready to race for £5995 incl vat  the equiv of about $8.5Kusd with the exchange rate of the time,  which was the price of a small new hatchback at the time.  Basically if you could afford a Ford Escort, you could afford a Formula First. 

Brands had a one make ‘winter series’ all at Brands hatch plus a one make National series around the country.  With the cheap buy in, low running costs (spec treaded race tires and under stressed running gear) they were massively popular for a few years.  Big grids with plenty of carnage, but it did launch several successful professional drivers including Ben Edwards, Oliver Gavin, Eugean O’Brian, Guy Smith etc.  Many BTCC drivers, a few LeMAns drivers and many F3, F3000 level drivers. 

One interesting facet was the simple bodywork on the early cars had an interesting aero issue.  The cars were faster in a straight line without the nose cone.  This was discovered accidently at first, but soon lean to noses being poorly attached then ‘accidently’ knocked off in first lap bumps.  Strange that.  The simple bodywork was attractive (to my eyes) but was later changed to a more streamlined less attractive (again to my eyes) version. 

The series started in 1987 and was popular through the early 90’s with the same cars.  It was still running when I left the UK and moved here in 94, but I think it died soon after that.  The cars were still tremendously popular (over 180 were built). Many were converted to sprints and hillclimbs with more power, wings or just as is.  Later many of the cars were sold to Norway were they were re-branded as ‘Formula Basic’ where they still run today.  Many UK race school used them until early this century (over 15 years) which shows just how right/strong/simple the original formula was.

Here are a few shots from back in the day, plus a vid if I can make it work.

The first race

<iframe width="560" height="315" src="https://www.youtube.com/embed/eVqELAPsz34" frameborder="0" allow="autoplay; encrypted-media" allowfullscreen></iframe>

Agghh, can anyone fix the vid link?

So why the interest?  Well as I say, they always appealed to me as a great simple concept similar to the old Staniforth Terrapins.  Also with the small size, short wheelbase and low polar moment of inertia, I see them as ideal for tight autocross and hillclimbs with slower tighter corners than road racing.  I think the compactness may help offset the lower CG of a longer (lower) traditional FF or similar.  Plus I think they could be built cheaply and easily from off many off the shelf parts.

Here are some more pics of the later body work both in the UK and once in Norway.

Here's is a nicely restored one with good detail shots.  This really shows the genius of the concept too me.

That's it for now. I'll post my daydreams and thinking for something similar for a home brew version later.,but I've got to go for now.

I've had similar thoughts and wonders - especially using a VAG B5 FWD chassis 1.8T as a donor, although I agree pretty much any transverse FWD combo would work as well. 

Funny you should mention a FF1600. A fellow in my autocross region recently bought one to run in C-Mod. 

As to why nobody has done it?  Well... I suppose whatever combination chosen would need to somehow fill a void not already occupied by F-Vee and F-Ford, either of which can be had for fairly cheap if you look. Or even F500 or F600.  The unfortunate reality is the drivetrain is not really the main expense when building an open wheel car.  In the case of F500, it's really cheap.  Not much more in F600.  It's the chassis and everything else that cost money, regardless of what's moving it.

There's nothing really preventing anyone from building such a thing and running it in A-Mod for autocross. 

I'll read through later, but just adding I love your pic dumps - haters gunna hate, but please don't stop. I'm assuming you've referenced "High Speed - Low Cost" ? I think he used a mini front end in the rear. It's my dream to poke together a single seater with a FWD based engine/trans in the rear. My crack brain plan involves squared off  "sections" so they can be bolted together and act as crumple zones, but also can be modular - not sure the feasibility in regards to chassis stiffness, but I'll still probably give it a try :)

Buy the MidLana book, use the FWD drivetrain of choice, gather your Miata suspension bits and modify the build to put your butt in the middle.

several years ago I learned that you could adapt a VW/AUDI 90 degree FWD transaxle to a ford 302 and it could take about 300-350ish hp.  First gear may be useless though...  (meh, skip it)

This has led to many an evil formula car thought...  

Uprights, brakes, steering rack and shocks/springs.   Those are the problematic things that often end up costing a lot.  Find solutions in production car (or cheap reliable and available aftermarket) and you might be somewhat on to something. 

Ian F said:

I agree pretty much any transverse FWD combo would work as well. 

Maybe even better than 1.8t the n/a'ers from civic or corolla..  Not familiar with the cool stuff pictured above, but all the production and DIY road cars with a modern FWD drivetrain behind the driver seem to perform well.

In reply to Apexcarver :

Lambo/GT40 Replica folks use BMW V12's or Ford/LSx V8's with Audi 016/01E transaxles.  The ones used on the 924/944/968 have some different gearing that might work better with some mixing/matching.  The actually handle the power quite well as long as you don't do drag launches and spit the final drive pinion out of it.  One guy built a replica for rental use and put a limiter in the hydraulic line for the clutch to slow the uptake and reduce the drag launch antics.  Works a treat.

Of course with a little less effort with adapters, you could adapt an Audi V8 to the Audi gearboxes and have a slightly more sportscar friendly mill (slightly better redline and less low end torque to break things)

I like your thinking though.

Apexcarver said:

Uprights, brakes, steering rack and shocks/springs.   Those are the problematic things that often end up costing a lot.  Find solutions in production car (or cheap reliable and available aftermarket) and you might be somewhat on to something. 

Look at the Midlana build for ideas.  He uses NA Miata parts and they are pretty sturdy while being fairly inexpensive and lightweight with custom control arms.  Shocks and suspension joints, etc. are all generic circle track/off-road pieces.  Some of the Locost builders use motorcycle shocks with bellcranks, etc.  Not ideal, but there are several solutions.

You could also use existing formula car parts for Swift, Van Diemens, etc. they aren't terribly expensive in the grand scheme of things.

There is a Focus ST that is totaled for almost reasonable money near me, I have been having these same thoughts.

Adrian- so is the point to come up with a new formula car that would be fast enough to be a career builder AND be cheap like the original F-Ford or F-V?

The cars you posted are pretty clearly not *that* hard to build.  

Or are you suggesting that there be a "spec" engine series where home builders can build their cars (with some specific parts for safety, of course)?

Or a single car you can build and compete with?

Lot's to reply too.

I should start with the motivation and whys.  I grew up going to club level races, hillclimbs and sprints in the UK.  I spent hours looking at home built or modified single seaters and sports protos.  There is absolutely no rational reason to build your own car from scratch.  I'm sure 11 times out of 10 you'd be better off buying an existing car such as a Formula Ford, Formula Vee, Spec Racers, old stock car whatever.  But as long as I can remember I've wanted to build my own car.   Let’s start with the background.  I’ve wanted a 7 since I started attended British kit cars shows in the early 80’s with my dad.  I lusted after Dutton’s, then the pre lit Westfield’s.  Then in the mid 80’s I got an early edition of Staniforth’s of the ‘Race and Rally car source book’  The one with the case history of the 79-81 split chassis Gould Terrapin for those familiar with the book, and was smitten with the idea of building a single seater.  As time progressed while still in the UK the financial reality just wasn’t there for either a 7 or a race car.  I did run an old Davrian mkVI kit car for several years as my  only car and daily driver.  That was fun when your eyes were the level of a Triumph Spitfires door handle!  In 94 I moved to the US, I thought for 6-12 months, but somehow nearly 20 years later I’m still here I’m a Citizen, married with kids and not going back!  On an early trip ‘home’ I visited Westfield, Dax, Ginetta, OMS and Jedi who made small 500cc race cars.  I was all set to order a Westfield when I decided to stay in the US permanently and bought a Mustang instead.  Since then I had a series of fun cars for the road, autocross and even a  season of road racing that would make heating your house by burning $100 bills in the fire place look like a good economy.  I got Ron Chapman’s book when it first came out and daydreamed on and off about a 7 again.  Then I got married, had kids and sold the toys, temporarily of course……NOT.  Now  years later I’ve had a few aborted project cars (Formula SAE, 323 GTX, Saab 900 Turbo) and I now have both the Vovlo C30 and 99 Boxster as daily drivers.  I still long for/dream about/lust after etc.  'building' a 'real' race car.  

I decided long ago that a 7 isn’t for me anymore.  Long gone are the days where driving the Davrian as an only car made total sense to me.  These days ride, comfort, NVH and oh, yes, not becoming a pancake are far more important than the thrill of a tiny open car, especially in Michigan where some of the pot holes could swallow a ‘7’ whole never to be seen again.  So If I’m going to build something it’s going to be a pure ‘race’ car.  By race car I really mean a fun autocross car and track day vehicle that could be used in time trials or even hillclimbs (I started off doing sprints and hillclimbs in the UK before I moved here).  Fun and safety is more important than combativeness.  Having seen the lengths people go to in terms of  time, effort and $$’s to win a bragging rights for missing some cones, I’m really not interested in seriously competing again.  Back when I autocrossed every weekend I was a solid top 10% on PAX at a local level, but solid bottom 5% at a national level.  That was when a set of Koni’s, a front stay bar and two sets of BFG R1’s (costing less than $300 a set) was national level prep in stock class autocross.  Truth be told with lots of practice I’m solid midfield fodder at best, so why kill myself trying to have ‘the best’ car out there.  Instead enjoy the journey.

Now I'll be honest.  I'm unlikely to actually do this, but without mental masturbation and daydreaming, where would forums like GRM be!

Next up my thoughts on how/what

Oh, and to those talking about transaxles and V8's or other high horsepower engine combos.  Big engines need more expensive consumables and are bigger and heavier.  A single seater or Clubmans car should weigh less than 900lb's with zero effort and could easily be less than 800.  Even 200 hp would be scary fast at that weight even with my fat arse in the middle.  The thought of possibly slinging a 400+hp sub 1,000lb monster up a tree lined hillclimb course is terrifying.  Also magic spinning snails of witchcraft and voodoo have a great ability to turn a 100-150-200hp 4 cyl into a 200-300-400hp fire spitting dragon with ease.  So for me.  I'd concentrate on a 100-150hp transverse 4 cyl and sub 850 lb's.

So what would I build if I did start on something?  Two options:

The first and even less likely would be a Clubman’s / Mallock style car as discussed in the other thread using a 1.6L Miata engine and box, RX7 GSL-SE LSD rear axle with 4 link and a panhard rod.  1.6L Miata front uprights etc.

The second, and marginally more likely that I’ll expand on in my next ramble (yes there’s more of this diatribe coming) is a single seater in the style of the Formula Firsts shown above or Staniforth's original Terrapin (more imaging whoring on those next) using a transverse engine and FWD gearbox.  The primary candidates are a Focus with a 2.0L Zetec,  an older Escort GT with a 1.8L, An Escort ZX2 with a Zetec, but the Mazda gearbox or possibly a late 80’s Ford Laser/Mercury Tracer with a B6.  Actually the perfect donor strikes me as either an AW11 MR2 or a Mk 3 MRSpider.  I would then plan on using the whole engine, gearbox and driveshaft’s with either the original FWD uprights/hubs, or in the case of the Mazda based offerings I think I could use Miata rear uprights as I ASSUME the driveshaft’s would have the same splines and fit the Miata units.  The biggest issue with the Focus is I don’t believe that 13” wheels will fit over the stock brakes so that would be more work.

The thing is where to start with a possible design.  I’ve got a huge amount of ideas in my head that I’ll outline briefly (yes this is brefly I promise you).  First to sort them out and second, every decision needs to be made for a reason and be defensible, not ‘just because’.  So, if anyone is looking at this and cares enough please chime in and comment.  I’ll start with my assumptions and provide my thoughts and justifications for them.  I’m looking for feedback so please, please, if anything I suggest looks wrong, sounds wrong or is wrong, let me know. 

OK, thoughts and justifications of the layout:

1. Simplicity.  To make this even manageable it needs to be as simple as possible.  That means it’s also cheap and has a possibility of being finished, if ever started, before I retire!
2. To keep it simple that means the use as many standard unmodified components as possible.  Hence the use of the standard driveshaft’s (which will dictate track width), uprights etc.  Yes I could reduce unsprung mass by fabbing uprights etc, but that’s a no no to my simplicity, time or cost rules.
3. Ditto the suspension.  I would use outboard springs and shocks.  Yes aero, unsprung mass and rising rate would be better/easier with push rod suspension, but that is a whole magnitude increase in complexity.  Outboard springs and shocks need one attachment on the lower wishbone and one on the chassis side.  Two brackets and you’re done.  Pushrods need an attachment on the wishbone, a pivot on the chassis, a chassis mount for the shock plus the actual bellcrank itself which involves several pieces of material, three bearings etc.  This massively increases fab time and cost.  There is one possible get out clause to this that I’ll come to later.
4. Why transverse not longitudinal?  Simplicity and cost.  FWD drivetrains are common and cheap.  Both the B6/BP and Zetec family of engine have been produced in massive numbers and are cheap and plentiful as well as having a significant aftermarket for cheap parts, and massive enthusiast followings for knowledge.  All are iron blocked and relatively heavy which is a down side.  The Focus/Zetec has the possibility to upgrade as a unit to the all alloy Duratech which is lighter, but not yet as cheap/plentiful in FWD form.  The newer 1.6L Duratec Ti-VCT from the Fiesta is too new to be cheap.  The newer engines also have far greater electronic issues to overcome.  The intention would be to use the full injection and ECU from the donor car (obviously with a thrifted cut down loom).  Also LSD’s are cheap (relatively) for the MTX 75 gearbox on the Focus, there are LSD’s available for the Mazda box, but I’m not as familiar with them.  An LSD could be a simle later addition.

So, next let’s try and define and defend some hard points and thinking behind them.

1. Rear track.  This is the defining dimension as by my rules it will be dictated by the FWD donor vehicle.  Using the Focus that would be 58.8”, using the Escort GT or ZX2 that would be 56.5”.
2. Wheel base.  This is defined by intended use, rules and the track wheel base ratio.  The only rules I’d have to worry about is B mod, which has a minimum of 80”.  Considering I need to fit into this thing and potentially drive it on tracks as well that’s way too short.  My gut feel was 90-92” which is about 6-8” short than a Formula Ford, but they are longitudinal mount not transverse.  Then I apply the standard rule of thumb of a track wheel base ration of 1:1.6 and lo it would come out as 90.4” for the Escort and 94” for the Focus.   So gut feel is right in line with physics.  I love it when a plan comes together.  The exact wheel base would be refined based on packaging and how reclined the driver would be.  My tendency would to be towards slightly shorter if a compromise is needed not longer.
3. Roll center height.  Now I don’t see this as being supercritical in its actual height above ground.  I think with the layout and style of the car the C of G is going to be very low.  The only negative impact on C of G is going to be the transverse engine trans combo which will be relatively high and possibly worse give a steep C of G axis, up towards the rear.  Obviously I don’t want it too high for jacking reasons and I don’t want it below ground as that would lead to the need for very stiff springs.  I’m thinking 0-2” in the front with the rear at  3-4”  This is something I would definitely want input on if I went ahead.  I’m also concerned about the roll axis inclination.  With the high rear C of G, do I need a higher rear roll center and steeper R.A.I?
4. For the front geometry I would go about it as follows. 
   1. Start with Miata, or whatever front upright I end up using.  Locate where the lower ball joint would be located with the intended tires (I’ll come to those next) and track (See above).  Then locate the inner wishbone  as dictated by the chassis width (probably 20” plus the bracket) but at the same height as the outer.  That gives me a plane Xmm long, parallel to the ground.
   2. Draw a line from the contact patch, through the desired roll center height (Start with 1” above ground then work from there as needed) to intersect with the LCA plane.
   3. The upper wishbone outer is located in the same way as the lower, the inner would be located by drawing a line from there to intersect where the LCA and roll center line intersect.
   4. Start with a UCA around 80% the length of the lower and see where the camber curve comes out. 
   5. Stick it all into one of the online geometry programs and see where it comes out as a starting point.
   6. Adjust as necessary J
   7. I would like to have very long swing arm lengths to help reduce roll center migration and to minimize scrub of the tires and they go through jounce and rebound.  The scrub is important considering the the surface of many autocross lots and hillclimbs will lead to a lot of bumps.  Minimum upset would be important to me.
5. For the rear I would follow basically the same process once I’d finished the front.  Starting with whatever the final RC height came out at the front I’d start around 1-2” higher (Would I need a great roll center inclination, especially given the high rear CofG with the transvers engine?) I would also aim for a greater camber gain in the rear as there is no camber gain due to steering.  Both upper and lower wishbones would have to be shorter due to engine packaging.  This will also lead to greater roll center migration.  Would that be an issue?
6. Bump and rebound.  I’m thinking for now, with my target 2-3” ground clearance I’d aim for 1” droop and 2” rebound.  That would allow for increasing ride height if needed.
7. Wheel frequencies, not sure right but leaning towards 2.0-2.5Hz as a starting point.  This would dictate initial spring rate and starting point for (hopefully cheap off the shelf) shock selection. 
8. Shocks, I’d want to keep cheap and off the shelf.  I know motorcycle shocks seem popular with many Locost and other builders, and they might work depending on what the wheel frequencies calculated out as with them.   The issue I see is most M/C shocks only seem to have 1.5 – 1.75” travel which doesn’t sound enough to me.  This is where I said I might cheat on my no inboard suspension.  Some of them seem to come with a rocker already built, so it becomes much easier.  The ratio seems to be around 1.9 – 2.0, so the 1.5” stroke suddenly becomes 3” which is what I was looking for.  The next question becomes, are these things in the ball park or at least close to the spring rate I need.  I think I’ve changed my view on this and would rather stick to the simple, outboard spring/shock units.
9. Caster and KPI, I’d be open to suggestions, but would probably go with the stock Miata value.
10. Now wheels and tires are obviously key to defining the location of the spindle.  My initial thoughts were to use either FF1600 or FF2000 autocross sizes as B and C Mod is a popular classes and cast offs should be cheap.  Checking on the Hoosier site shows that FF1600 fronts are 21” diameter and FF2000 fronts are 20.8” diameter, that’s only 0.1” difference in radius  so no problem switching between the two.  FF1600 rears are 22.6” diameter and FF2000 rears are 22.4” so again no issue in swapping.  I then thought that I could possible use cheaper R comp DOT tires as well so again I went looking.  In 13” R comps there’s a 205/60 at 22.8” and a 225/45 at 20.9.  That’s awkward as the narrower tire is the larger diameter, not what I need.  Then looking in 15” there’s 205/50 at 22.8” and a 225/45 at 22.9”  That could work depending on my front ride height and camber curve.  It’s just a though.
11. Initially wheels would be cheap steel (Diamond, Aero or similar) 13x6 fronts and rear for FF1600 tires or 13x8 for FF2000 rears.  Yes they are heavy, but several D Mod ‘7’s seem to use them to good effect.  Ditto if I went for the 15” DOT R comps.
12. Steering rack, that’s something that I think my life would be easier by getting a single seater or small buggy  rack.  I’d use that so I could set the tie rod length to be proportional to the difference between the upper and lower wishbones and set the height for zero bump steer.  This is one issue I see with the Miata uprights, I’d love to have the steering arm at the same height as the upper wishbone so a)bump steer would be easy to calculate and b) the steering column would be above my toes making pedal access (heel and toeing) easier.
13. The chassis from the roll hoop forward is relatively easy.  Its job is to locate the suspension pick-ups, steering gear, my fat arse etc then tie it together with maximum triangulation and minimum number of tubes.  From here back it’s a little trickier.  The engine/trans is going to be wide for a single seater so the main chassis ‘rails’ will have to kick out.  I’d plan on having the rear roll bar stays spreading out and locating near the rear shock pick up points.  I imagine I’d need a removable cross member across this point to facilitate engine removal.  I’d probably plan on a diagonal across the rear as well, also removable.  I’m concerned that the top of the engine bay would still be too open and flexible.  I can picture all this, I guess I need to make some sketches.
14. Reading the GCR (9.4.5) it appears that the front and rear hoops plus side brace between the two can be 1.0 x 0.080” seamless, It might be easier to use 1.375 x .08”.  It looks like the hoops have to extend to the ground, although I’m unsure if they sit on the chassis rails or go all the way to the floor level.
15. For the floor, bulkhead at the roll hoop plane, the front of the chassis and the plane of the pedals/master cylinder I was thinking of welded or brazed in 18swg steel shear panels rather than alloy paneling and triangulation.  The reason for this is twofold. 
    1. You need something there anyway, but if you go for alloy paneling you still need to triangulate those areas, with a steel shear panel you do away with those tubes so I doubt it would end up much if any heavier. 
    2. Steel on the bottom give greater protection to the soft squidgy bit inside and increased abrasion resistance compared to alloy.  The sides would be traditional riveted on alloy paneling. 
16. As the heavy engine is going to be offset to the right, I’d place the battery and radiator on the left to counter that.  This would be a balancing act and I’d imagine final placement would be decided once partly built so I can check weight and F/R Vs. L/R balance.  I’d want them as far back as possible to help the cross weights, but as far forward as possible to prevent a too rearward C of G.  Advice?
17. For the fuel tank I’m imagining a small fuel cell right behind the driver in front of the engine.  When I say a fuel cell I’m talking a small (5 gal?) circle track cell not an FIA cell due to cost.
18. I’ve got some mental thoughts on upper bodywork, but that’s not important for now. Other than I imagine a plan shape somewhat like an old Brabham BT52 due to the wide engine and rear placement of the radiator etc.  I was wondering about a full width/length under tray though to help the aero, this would be alloy not steel like the floor, supported by guy wires from the upper chassis rail to prevent it collapsing.
19. Aero.  Initially nothing, later the possibility for front and rear wings.  This will affect wheel frequencies and rate so has to be born in mind, especially with my concerns over M/C shocks.

Thoughts?  Have I lost the plot or do people think this is any kind of good idea?

That’s about where I am right now.  Please provide feedback, I have a thick skin.

Slow day at work? 

I haven't read through the full plan, but you've checked and are aware of circle track parts? They're cheapppp in the US, especially east coast, and so far as I'm aware most are fine for making things go left and right. Shocks, brakes, and steering can be pulled off. 

Picture
Unprotected master cylinders on this one make me a bit nervous (especially for brakes!).

Feeling a bit of deja-vu here.  FWIW, we've kinda had this discussion:

abarath-sp-1000-tribute-build

Personally, I think your weight target is more than a bit optimistic.  The SP1000 referenced above using a MC engine/trans is still looking at around 1000 lbs or so using somewhat pricey race car parts to keep the weight down wherever possible.  The J15 Fury is around 1200 lbs and I've seen that car - there's nothing to it. And the Fury isn't built to any real standard with regards to racing safety.  If you want to possibly run the car in TT or HC events, you'll need to keep the applicable rules in mind during the design related to tubing diameter and thickness.

In reply to Adrian_Thompson :

Re: #16- are you making a Clubman car or a mid engined transaxle car?  Most of the notes seemed like the cars pictured in this thread, but #16 with the engine on the right makes me ask.   Or do you expect that your donor will be that biased to one side?

In terms of the front suspension, while it totally makes sense to use a Miata upright (rear works too, I bet)- the actual arms would have to me more like what Keith wrote up in his Miata based Locost book.  And if you don't want to make them- the arms are available from circle track suppliers for good prices.  Shocks, too.  

Tom_Spangler said:

Slow day at work? 

To be fair most of what I wrote I had written a couple of years ago so it was more copy, edit and past.  Nut yes, I wasn't rushed off my feet.

accordionfolder said:

Picture
Unprotected master cylinders on this one make me a bit nervous (especially for brakes!).

That may have been the case for those cars, but not necessarily how I would do it.  Also, these cars hit each other A LOT in the day, at times purposely to knock off the nose cone (see higher straight line speed mentioned up thread) and there was never an issue.

Ian F said:

Feeling a bit of deja-vu here.  FWIW, we've kinda had this discussion:

abarath-sp-1000-tribute-build

Personally, I think your weight target is more than a bit optimistic.  The SP1000 referenced above using a MC engine/trans is still looking at around 1000 lbs or so using somewhat pricey race car parts to keep the weight down wherever possible.  The J15 Fury is around 1200 lbs and I've seen that car - there's nothing to it. And the Fury isn't built to any real standard with regards to racing safety.  If you want to possibly run the car in TT or HC events, you'll need to keep the applicable rules in mind during the design related to tubing diameter and thickness.

I'll go and read it later, I just looked and unfortunately all pictures were wiped out by the  great phtosuckit massacre.