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ae86andkp61
ae86andkp61 Reader
12/4/14 7:15 p.m.

How about the lightweight setup from DP Cars as a cost-no-object option?

http://www.palatov.com/products/suspension.html

Ian F
Ian F MegaDork
12/5/14 8:54 a.m.

In reply to ae86andkp61:

That's actually not bad. Cheaper than the Formula car upright sold through Pegasus. Not saying it'll be cheap, but there are more expensive options.

mblommel
mblommel Reader
12/5/14 3:59 p.m.

You guys are quickly pricing this build out of my budget.

jmc14
jmc14 Reader
12/5/14 4:43 p.m.

I think that there may have to be a couple of options for the build. 1 for the guys that want to build it high end and the other for more modest budgets. (like mine) I'll work on that.

MrJoshua
MrJoshua PowerDork
12/5/14 6:08 p.m.

I've been thinking about ways to make the mechanical bits of this build as single donor as possible and cheap. How about Subaru motivation like the 818 but make the basic build naturally aspirated. There are bad head gasket Subarus all over craigslist so they are cheap. They have short motors and have a transmission that can be easily modified to be mid engined. All 4 hubs have provisions for drive axles so you can use the motor in the rear and still keep the front hubs for the front of the car. Low center of gravity for the motor. Just an idea.

Ian F
Ian F MegaDork
12/6/14 9:11 a.m.
mblommel wrote: You guys are quickly pricing this build out of my budget.

Not really... there are high-end options and cheaper options. The difference will be in the weight. There's also little that says you can't build the car with something cheap like Miata or Spitfire up-rights and then convert to more high-zoot uprights at a later date.

The issue with the Subie drive train might be width. While it's short and low, it's also wide. It may be difficult to design a chassis that would accommodate everything.

MrJoshua
MrJoshua PowerDork
12/6/14 9:28 a.m.

In reply to Ian F: IIRC the motor is ~30" wide. That may be a deal breaker . My vison for the suspension would use Subaru uprights with custom lower suspension arms (or shortened Subie arms) in the rear. The front would use Subaru front uprights and lower a-arms. The suspension design all around could stay with a strut setup or use custom upper a-arms. I love the idea of as single donor as possible. I also love the idea of a bike motor.

mblommel
mblommel Reader
12/6/14 10:40 a.m.
MrJoshua wrote: I've been thinking about ways to make the mechanical bits of this build as single donor as possible and cheap. How about Subaru motivation like the 818 but make the basic build naturally aspirated. There are bad head gasket Subarus all over craigslist so they are cheap. They have short motors and have a transmission that can be easily modified to be mid engined. All 4 hubs have provisions for drive axles so you can use the motor in the rear and still keep the front hubs for the front of the car. Low center of gravity for the motor. Just an idea.

The Subaru idea isn't bad, but aren't Subaru mechanicals pretty hefty? I guess the smaller 1.8L engine is pretty light. We have to remember this was a 1.0L car that weighed under 1500lbs. The 818 is a porker by comparison. I know high end formula car parts would be the best to keep the weight down, but how durable would they be for any possible street use? Personally I'd like to have a toy that's easy to use and not overly fragile. There are several good FWD transverse choices out there that I think would work well. Toyota 4AGE, 1ZZ, 2ZZ; Honda D series; Mazda B6; Suzkui G13B. All of these have 200,000 mile durability, reverse, 5 or 6 speeds and cheap. Additionally none of them have to have anything "converted" to work. Most have good motorsports support and easy to find parts (OK, not the Suzuki but I have always liked that little engine). Just my thoughts, lets keep the discussion going.

FWIW some seaching seems to indicate Portege, 323, and MX3 front hubs are all interchangeable with early MX5 rear hubs. So if MX5 uprights were used a MX3 transverse B6 might be pretty easily done mid engine.

Ian F
Ian F MegaDork
12/6/14 11:36 a.m.

In reply to mblommel:

It depends. The "add lightness" school of thought is if your overall package is light, then you don't need crazy-strong parts to withstand road stresses. But it will always be a bit of a balancing act and if you push the limits of lightness, then you have to be willing to accept some potential failures of pushing too far. Especially when a budget is added to the decision process.

Essentially, the downside to this is the old adage: "Light,Strong,Cheap - Pick Two."

jsquared
jsquared Reader
12/6/14 12:51 p.m.

I'm under the impression that the Subaru stuff isn't that heavy. I never weighed mine when apart but the naked longblock wasn't that bad. Even with accessories and intake manifold it maneuvered pretty well on the hoist.

If you're looking at a transverse package, I think the Honda K-series is hard to argue against from a bang-per-buck/availability/upgrade-ability point of view.

bpimm
bpimm New Reader
12/6/14 1:07 p.m.

In reply to jsquared: The K series is a good powerplant, my only concern is the height, it's a fairly tall engine and this car is onlt 36" from the ground to the top or the roll bar.

Once jmc14 has the mold in hand we'll know more about the available height for the powertrain.

jmc14
jmc14 Reader
12/6/14 2:38 p.m.

Great discussion. Thank you for all of the input.

I paid for the molds and shipping awhile ago but it's been a pain trying to get them packed and picked up by the freight company. I was just about to get on a plane and handle things myself when I received word yesterday from the freight company that they have them packed, are loaded, and are on the way to me. They are coming from CA and I'm in NY.

I want to build a Hyabusa powered car and I will do that. But, for a less expensive option what about using the entire suspension, hubs, brakes, engine, and gauge cluster from an NA/NB Miata? The track has to be narrowed by about 2 inches per side. I've done this before when I narrowed the suspension from a C5 Corvette to use in my Cobra tribute. To narrow the track I kept the control arms stock and simply moved the suspension mounting points in by 2 inches. I had a steering rack made with the inner tie rods narrowed to match. I would do the same thing and replace the Miata rack. I paid around $200 to have the rack made. (That was 10 years ago though)

I have built a few Miata based cars. Including building a space frame for the Miata cradles to bolt into. For the Stinger I wouldn't use the cradles. The suspension pick up points would be part of the frame. I have 2 complete spare drivetrains and suspensions. Including 1 that is supercharged. I wouldn't use the Miata shocks. For the space frame build I used small body aluminum coil overs with out a problem. This allows the upper shock mount to be low.

I think the Miata engine will bolt to the 1989-1996 Mazda Protege/323 FWD transmission. They were available with a 5 speed manual and LSD. A quick search on Ebay shows a good number of them available for cheap money. Can anyone confirm that the Miata engine will bolt in?

We all know that there is a ton of high performance parts for the Miata. Including tubular control arms. A builder could keep things inexpensive or upgrade as they wish.

I think the Miata engine mounted transverse will fit the body. I have seen the height of the Abarth listed from 36 to 39 inches. I believe that 36 is to the height of the body at the rear bulkhead. I think 39 is closer to the top of the roll bar. I'll find out shortly.

Having fun

Chet
Chet New Reader
12/6/14 5:13 p.m.

John,

I'd obviously concur with the Hayabusa as first choice. If you want an easy car power train solution I'd suggest you look at the current Ford Fiesta 1.6 powertrain. The engine was actually designed by Yamaha and is extremely lightweight and very compact. It also has the right kind of power and quick revving feel for a sports car. There are numerous performance parts available from the UK and you really don't need 200 HP in such a light car.

Caterhams use a version of this engine with great results.

bpimm
bpimm New Reader
12/6/14 6:20 p.m.

In reply to jmc14:

The Miata engine should bolt right up to the transverse tranny because that is where it came from, it was a transverse engine they mounted longitudinally.

Using the whole suspension from a donor makes a lot of sense, there is a ton of goodies for the Miata chassis but you would need to source the transverse drivetrain in excess of the car, If you used a FWD donor then you would need to source a front suspension from something else and modify the rear to get rid of the struts.

IMHO I would start with a good suspension (Miata) set up for a coilovers or an inboard spring/damper setup and buy the trans separate. I think that is a better recipe for success that trying to adapt a strut type upright to dual wishbone duty.

The stock brakes on the Miata should be adequate as the car will be 1000Lbs lighter and there are many upgrades available if you choose. My 1.6 Miata with stock brakes/EBC yellowstuff pads can handle 20 minute track sessions and the rotors only turn a nice shade of blue ~600* and I use them hard the whole time. I can't out accelerate anyone so I have to out brake them to keep up.

I too will be using the Hayabusa with the Powertec/Quaife quick change with reverse as I already have it. I would love to add the Geartronics shifter setup but that is a big chunk of cash just for that. Mine uses a Pingle electric shifter now and up-shifts are 95% reliable but down shifts are less than reliable because the electric solenoid doesn't have the power to pull it out of gear while off throttle engine braking so the down shifts have to be timed to when you are just starting to roll the power back on. The Pingle is a bike shifter so it has a 1 sec delay on down shifts to keep form locking the rear bike tire on multiple down shifts which is a real pain if you need to drop 2 gears as you roll on the power.

bpimm
bpimm New Reader
12/6/14 6:25 p.m.
Chet wrote: John, I'd suggest you look at the current Ford Fiesta 1.6 powertrain. The engine was actually designed by Yamaha and is extremely lightweight and very compact. It also has the right kind of power and quick revving feel for a sports car. There are numerous performance parts available from the UK and you really don't need 200 HP in such a light car. Caterhams use a version of this engine with great results.

I have been looking into this as a transplant for one of my X 1/9's. Ford motorsports is going to be releasing this engine as a crate engine soon, I'm assuming they will release a standalone ECU with it like they did with the 2.0 version which is already available. I would only be looking at the ECU and picking up a low mileage engine/trans out of a wreck to go with it. Either the 1.6 of the 2.0 would make a great package for this little guy if they will fit under the engine cover.

bpimm
bpimm New Reader
12/6/14 6:31 p.m.

Here is a little teaser of what the Busa can sound like. link

mblommel
mblommel Reader
12/6/14 7:11 p.m.
jmc14 wrote: The track has to be narrowed by about 2 inches per side. I've done this before when I narrowed the suspension from a C5 Corvette to use in my Cobra tribute. To narrow the track I kept the control arms stock and simply moved the suspension mounting points in by 2 inches.

If you keep the same pickup points and control arms but shift them inwards toward the centerline of the car wouldn't this raise the roll center?

After the discussion today I'm now cruising craigslist for a roller 1.6 Miata with no engine or tranny and a good running MX3 with a 1.6 and a 5spd.

jmc14
jmc14 Reader
12/6/14 7:22 p.m.

Thanks for the suggestion Chet. I really like the idea of the Fiesta 1.6. First of all it's a current engine/transmission. That means that great low mileage parts will be available for the forseeable future. I did a quick look on Ebay and the engines and trans are very reasonably priced. I also see that Quaife has an LSD for the transmission.

I have looked at using the Subaru engine/trans. But, I think that it's to wide and long to fit.

It looks like I will have to jig for a few different engine/trans combo. I know that every builder will have their own idea for the build.

Thank you bpimm for your thoughts on the build. And, thank you for the awesome link.

jmc14
jmc14 Reader
12/6/14 8:11 p.m.

Mike, when I wanted to build a space frame for the Miata parts I started searching Craigs list for a Miata. The first one that I found was a 1990. It had 89,000 miles on it. I bought it for $1200. It ended up being such a good running car that I didn't tear it apart. I've driven it trouble free for 3years now.

The second one I got for free. It was completely trashed but running. I drove it onto my trailer. I pulled that one apart for my build.

The 3rd one I paid $2000 for it. Its supercharged with lightened flywheel, aftermarket clutch, aftermarket header, boost control, and a Torsen diff. It runs great. I have it sitting in my shop.

I am not an engineer ( I hire them) but from what I understand you are correct about raising the roll center when the pick up points are moved inboard. I said that the Miata track has to be narrowed by 2 inches per side. I think that I overstated that amount. The Miata is 65.7 inches wide. The SP 1000 is 64 inches wide. The Miata track is wider by 4 inches but I'll bet the actual tread width is close. A lot of the difference is in the wheel offsets. I think that the narrowing that will be required will be negligible and will not greatly effect the roll center. Plus if we run shorter tires we can get the difference back. :)

The frame that I build will be set at 4 inches of ground clearance. Because the frame wraps around you the seating position and weight is really low. This will help the handling as well.

singleslammer
singleslammer SuperDork
12/6/14 8:17 p.m.

If you run suspension from a Miata, I already have a parts car! Are you thinking that would be the starting point for all the cars or just the low end car? This car NEEDS a high revving bike engine and that is totally the build I want to do. If I did car power, I think that the Fiesta option is a better starting place than a Miata engine. Much newer and easier to find a nice healthy example. However this is going to require a few different major donors instead of just a Miata and a Protege transmission. Anyone have any ideas for axles for either engine (bike with dune buggy diff or Car motor)?

bpimm
bpimm New Reader
12/6/14 9:19 p.m.

Watch here for the 1.6 ecoboost to be available, as far as I know no one has cracked the stock ecu yet so you have to maintain all the anti theft C**P and whatever they tie into the ecu these days to get it to run. Once there is a standalone ecu available things will be much simpler. I was told when I talked to ford racing that the 1.6 will be released in 2-4 months and that was about a month ago.

The 2.0 may be a good option as well and it's available now. I have a dimensioned drawing of it I'll email if anyone is interested. Just need someone with a Focus ST to get some measurements with the tranny.

Brian

Ian F
Ian F MegaDork
12/7/14 7:23 a.m.

I suppose one thing about the build of this car is it will depend a great deal on what the builder wants out of it. Personally, my goal is essentially a B-Mod car that can be driven on the street and be moderately competitive (locally). As such, making the car as light as possible will be a build criteria and I don't expect it to be cheap. I really have this crazy idea of either rigging up a removable rear tire rack or a hitch to tow a small trailer to haul race tires to the site. And being a Mod car, they would be pure race tires, not anything DOT rated.

I hope this works out... might keep me from spending a crap-ton of money on the new Mustang GT350...

MrJoshua
MrJoshua PowerDork
12/7/14 7:40 a.m.

Wow, with the total overall width you will probably be able to use miata stuff with no issue. That would be great from a cost and simplicity standpoint. Something that might make shock selection easier on a Miata front suspension would be a custom upper a-Arm that allows the spring to pass through instead of sit above. That should allow a more normal shock length/travel and low front upper shock mounts.

jmc14
jmc14 Reader
12/7/14 8:37 a.m.

I'm using a small body aluminum coil over with the stock front upper A-arm on one of my cars with out a problem. The spring does fit inside the stock upper A-arm. This shock is used a lot in Dwarf, legend, and Midget racing cars. But, a custom upper A-frame would allow a larger selection of shocks. Maybe there is already a company that makes it.

I like the fact that there are tubular replacement A-arms for the Miata, upgraded hubs, spindles, brakes, bushings, and more readily available.

My thought is to use the Miata suspension pick up points on all of the frames.

mblommel
mblommel Reader
12/7/14 8:51 a.m.

Sounds very cool John. It's shaping up to be buildable as a mid engined version of "the answer" that is 1000lb lighter with a body that's 1000X better looking. I'm wondering if a mix-n-match of various 323, Protege, ZX2, etc. axles might produce an off the shelf solution to use the miata hubs in the narrow track width. If not a call to raxles would fix it.

The newer engines are tempting, but sorting out all the wiring issues seems like too much of a hassle. OBD-0 wiring is pretty simple. The engines from the early to mid 90's are great because you get the reliability of fuel injection and distributorless ignition without all the hassles of new car stuff.

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