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We've been hard at it the last couple of weeks starting another Grassroots Challenge car in Portland and I'm pretty excited about our progress, so thought I'd share. I'm excited because today the engine found its new home and we have confirmed that the powertrain and tires will indeed fit, now it's just a matter of lots and lots of fab work to make it permanent.
Here's the plan:
The body - This is definitely my favorite part of the project, a 1972 Honda N600. I first saw one of these at a Honda dealership in Idaho many years ago and knew that I'd have one eventually. I bought this one in November 2009 with intentions of making a project car out of it...took me a while to decide what to do with it. It was sold to me as a "fixer" car for $1500...it hadn't been running for a while and supposedly needed a starter and a carb rebuild. The body was also half-primered and missing a few trim and interior pieces. It was a runner in short order and a hoot to drive around, but the stock 600cc engine just wasn't cutting it. My buddy Aaron and I kicked around lots of ideas and eventually he talked me into building another $20XX challenger.
For those who don't know much about the N600, it's basically Honda's version of an old Mini. It was the first Honda that was officially imported to the US. Here's a picture of the car shortly after I got it, parked next to a Smart at work for a reference of size.
The donor - I love to keep it in the family, so I had to use a Honda powertrain. A motorcycle engine was the initial plan for the awesome power:weight ratio, but the budget:power ratio wasn't so great. Instead, we decided an early B or D series equipped car would make for a proper donor, and as many parts would be reused as possible. I eventually bought an '89 Civic STD that was not only a runner, but had some decent aftermarket parts on it and had a D16 swapped into it. The clutch was on its last legs, the car wouldn't pass emissions, the interior was soaking wet due to some nasty water leak, and the seller wanted to unload it quick. I bought the donor for $660 and drove it to Aaron's house. The car is now naked of its useful bits and looks something like this:
The plan - Number one priority is to keep the car looking close to stock on the outside. No box flares and no crazy body work. Number two priority is to keep it under the $2011 budget, for obvious reasons. Number three priority is to keep the weight as low as possible on the budget, we're targeting 1500 pounds complete. The Civic engine is going in back, of course, and we plan to try and stretch our fabrication skills a bit with this project. Aaron and I are doing the majority of the work, but of course a project like this is easy to sucker friends into helping with! I like Honda engineering, generally speaking, but there's not much left to do to a Civic that hasn't already been done so they're just too vanilla for my tastes. Hopefully this will be something new to the Honda world and definitely something new to the GRM world.
Obviously, there isn't another West Coast challenge, but it seemed appropriate to call it that since there aren't many of us left coasters building challenge cars. This one will end up in Florida this year, if all goes to plan.
Reference links (I'll probably add to this as I go):
April 4 - Rapid prototyping the tubes
April 8 - Making room for the front tires
April 17 - Dry ice tarboard removal
April 19 - Relocating pedals and starting sheetmetal
April 27 - Starting the roll hoop
May 1 - Welding in the dash bar and rear cradle plate
May 24 - Starting the engine cradle
June 26 - Done with the rear tubing!
July 17 - The rubber meets the road
August 24 - Copying Kirkey
August 28 - Structure welded in
September 6 - It's ALIVE!
September 14 - First peek at paint
September 22 - Finally, assembed!!!
October 9 - Challenge wrap up
January 13, 2012 - Pictures from the event
June 17, 2012 - Rising Sun roof
Having done some measurements, it was immediately obvious that there wouldn't be room for a heck of a lot of rubber between the body and the powertrain. The donor car had some 205 wide tires on 15x6.5 wheels and there wasn't a chance that was going to fit. The 15s also looked HUGE on the little car. I got some 13x5" steelies locally and they seemed much more appropriate at first glance. After some digging, I decided to track down some Civic VX wheels. 13x5 with a 45mm offset and only 9 pounds a piece was perfect for our application. I got some for $125 from a local craigslist ad. There isn't much for tire choices on narrower 13" wheels, but I'm hoping to track down some used up Hoosier R6s which are still available in a 185/60R13. Meanwhile, we have up some 185/70s mounted up to the VX wheels for mock up.
The next thing to figure out was how to get some suspension bits to hold tires. After doing some rough mock ups, it just wasn't looking pretty trying to fit the Civic front suspension into the back of the N600. It also looked like it'd be a heck of a lot of work to modify the Civic rear suspension for a drive hub. I tracked down some Civic AWD rear control arms and they had some promise. After cutting away the forward section of the control arm, we were finally starting to see progress. The forward section will get re-built later. The AWD hub has the same splines as the FWD axles and it is all stamped steel, so that made it an easy sell to use the AWD parts and modify as necessary.
Fast forward through lots of car teardown, metal cutting, and today we got to finally see some real progress:
It's a tight squeeze, but it is starting to look like we've got a shot at making this concept a reality.
Yet again, I'm thoroughly impressed by the the fabrication savvy and engineering ingenuity within the GRM community. Good luck, and keep us updated!
I like where this is going
When I mocked up the Northstar in the back of mine the wheels had to reside outside the entire car.
It's funny how big those tiny little civic wheels look in there. Should be a really cool challenger.
When you first started talking about a N600 build I hoped you might be building a car powered by a highlander hybrid rear diff/motor.
Looks awesome, building a mid engined econobox is definitely on the bucket list. Thumbs up from a fellow Oregonian.
I like it!
This is a wicked cool project Bryce!
Fantastic project, and I'm certainly not one to bet against Bryce, but it's going to be awful narrow. Will it stay on four wheels?
Good idea getting a car small enough to mail to florida.
This is Awesomer than a bunch of stuff.
I can't wait to see the build! $2011 or $2012?
kreb wrote: Will it stay on four wheels?
It managed to stay on four wheels for the last 30 years, I'm hoping to continue that trend.
miatame wrote: $2011 or $2012?
$2011, for sure. I built the hybrid AWD Fiero in 90 days. This time I've given us over double the calendar time. Not saying it will be easy, but it will be less hard.
Nashco wrote:miatame wrote: $2011 or $2012?
$2011, for sure. I built the hybrid AWD Fiero in 90 days.
jeff, we're doing something wrong.
You're not the only one!
Very cool! Look forward to seeing it in Gainesville
Where did you find an N600 anyway? I've been looking for one for a while now.
killerkane wrote: Where did you find an N600 anyway? I've been looking for one for a while now.
Same place I find almost everything I buy....craigslist, of course! There are currently two of them on Portland craigslist, both cheaper than this one. They're relatively common out west if you're actually looking for them, you just don't see them on the road.
I was kind of hoping to see the word Powertrains.
One prius cell in the front will finish a 30 second autocross, wouldn't it?
alfadriver wrote: I was kind of hoping to see the word Powertrains.
Meh, I've done that one already. This time I'm going to try adding lightness instead of adding electrons, very different focus.
Edited to add:
alfadriver wrote: One prius cell in the front will finish a 30 second autocross, wouldn't it?
No, not by a long shot. Even with three Prius packs, the batteries can't keep up with my motor for more than 10 seconds. To really get full power from the motor for a full drag pass and a full autocross, about 5 Prius packs would be required. That's 400+ pounds of batteries! Now, if I could get my hands on some lithium, I could cut that weight significantly...but can't get it in the $20XX budget just yet.
a friend of mine had one for a little while. I dont remember much except that the stock shifter comes out through the dash...it was very obvious this was a car built with motorcycle parts bin engineering...it was friggin cool
LIKE LIKE LIKE!!!!
Time for an update. The Civic donor shell is now gone. We've also been acquiring more parts. This week's scores include some used up eBay turbo parts ($20), Walbro fuel pump ($10), used AGX dampers ($60), spare 4 speed trans ($15), used clutch ($10), crank pulley without damper (free), and cam pulley (free). No idea what will end up on the build, but it's been pretty easy to start accumulating Civic parts compared to most projects I build. Still haven't pulled the trigger on any tires, but we need to commit to some pretty soon.
We spent some more time figuring out suspension clearance and link types and we're getting pretty close to a workable solution. I'll spare the gory details until we actually make it work; it doesn't LOOK like much progress, but we spent several hours working out the kinks.
Tonight was spent doing some rapid prototyping. Ok, it was really just using PVC and duct tape, but it really helped to create a clear visual for us instead of continuing to wave our hands around and pretend like it was going to magically work itself out.
We started by making a main roll hoop. The intention is to make this part of an SCCA compliant cage, that way if this car is ever intended to be SCCA Solo legal in a mod class, the hard part is done. We used 1.5" diameter tubing, not sure if we'll end up using 1.25" or 1.5" diameter DOM, we're hoping to use 1.25" with the target of staying under 1500 pounds. With the size of this car, every bit of space and weight counts, so the reduce radius on smaller diameter tubing will go a long way.
It's tough to tell in these views, but the engine has been tilted towards the front to improve the clearance for upper suspension links on the back side of the engine. The turbo setup looked like it was made to hang way out front of the engine, but we reclocked things and we're confident we can make the turbo live tucked up into the engine. It might take some fooling around with the manifold/turbo flanges to get the turbo just a tiny bit further away from the engine, but you get the jist. The turbo doesn't look to be in great shape, and the manifold needs some repairs, but for the price they're great starter points. The attentive observers will notice some crank pulleys in the background of this shot as well, we're fooling around with different pulleys to see if we can keep the stock alternator in the stock location. The crank pulley is right up in the suspension area, so we're having to pull out a few stops to make room. More on that soon.
Here are a couple shots showing where we intend the forward links to go. As you can see, not much room to work with between the rubber and the powertrain. That PVC is about 1" outer diameter.
We still have a few question marks on how we want to do the cradle/cage tubes, particularly under/near the oil pan and the upper links, but putting tubes in space helped to hash out some details and get comfortable that we'll be able to pull things off. Pretty soon we'll need to make a main hoop so that we can start working from there with real tubes in space. We'll probably use a combination of 1" and 3/4" ERW for the structure, it's supposed to be slightly stronger than PVC. Not sure what we'll be MIGing and TIGing, but either way the welding is also expected to be stronger than duct tape.
It is impressive that you are managing to fit a full size Honda engine and a suspension in there. That thing should be a riot (and pretty competent race car as well)
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