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Guinness is good stuff. So good, in fact, that I named my dog after the beer.

Some update photos from today:

Here's the front of the car with both lower A arms done done DONE!


Low and mean looking!


Here are the lower rear A arms finished with the clevis plate welded in place:


Lower arms with the toe adjusters:


Here's the rear suspension DONE, minus pushrod & shock...




Here is how the rear shocks will sit:


Rear shocks sitting in place with some additional triangulation tacked in place on the differential cage:




Some detail photos of the front pushrod brackets. I got them about as close as possible to the balljoint. I think this should work well:




The alignment of the rear upper A arm pushrod bracket and the shock structure:


Measuring for the pushrod adjuster tube:

Woohoo!!! The rear suspension is actually supporting the car now!

I'll post up some photos tonight, but as it sits, both rear coilovers are in and I can bounce the back of the car by standing on it.

One question I have for those that have finished their suspensions.. how much does the car drop when you get in it? The back of mine drops about an inch or so when I stand on the back of the car. I'm t hinking its still a little soft. I built plenty of adjustment into the mechanism, so I can tinker with it until I'm happy with the results. It looks like it should work well though once I get it all sorted out.

depends how much you weigh, but if you're say 200 lbs, that means you've got an effective spring rate of 100lbs/in

Ok, that makes sense. These Ninja monoshocks must have a much much softer spring rate than I anticipated. I was basing all this off a 600-700 lb/in rate.

No big deal though. The way I've designed the rear suspension, to change the rate, all I have to do is insert a taller pivot tower between the A arm and the shock. The initial towers had 5 positions of adjustability, each an inch apart. I started on the lowest and worked my way up to the top position, which gives me about 2:1 ratio from the wheel to the shock, but its still too soft, meaning that these shocks must have around a 200-300 lb/in rate! I have enough room to go up a little more, or drive the mechanism via one of the lower adjustment holes, giving me closer to a 1:1 rate, but a much shorter pushrod.

I'm gonna sit down with the calipers tonight and see if I can calculate out the spring rate for these things and do a little math to see how I need to adjust the suspension.

Here are some pics of the rear suspension:

Wow! That really looks good. I hope you have room for a gas tank. My Locost is real tight. It maybe compresses a 1/4" when I get in. It rides hard. Russ

Yep.. I've designed with a fuel cell in mind that will fit behind the diff cage structure. Here is the cell I'll be using:



This cell measures 9" wide, so it gives me 1/4" of room between the diff cage and the rearmost vertical chassis members of the car.

I'm hoping I can work out the too soft suspension issue by redoing my linkages using a small rocker up higher than the current one. I'll also set it up so that I can exert up to a 1:2 ratio of pushrod movement to shock movement. Right now, I have a 1:1 pushrod to shock motion, which translates to about 2:1 wheel to shock motion ratio with the measurements in the photos above, and its still too soft. I think optimum will be around a 1.5:1 motion ratio.

Last night, I modified the OEM 240sx front struts and turned them into upper balljoints for my front suspension. Turned out very nice and looks like they will work very well with the front suspension. They will use high misalignment rod ends mounted in double shear as the upper joint.

Now, I've got measurements to order my upper A arm parts for the frontend. I'll post some photos up tonight, as I didnt have time to take any yesterday.

fan you are fast! Build is looking great!

do have rack and pinion steering on the 510? I know someone who just bought one and wants to convert. Thanks.

Nah just have the stock box and whatnot on it. I've heard of lots of people doing a rack and pinion conversion though. All you have to do is find a rack the right width and fab up some brackets to put it in.

Thanks. He's not much a of fabricator - I think he's hoping for a bolt in kit of sorts.

Some new photos from this weekend:

Got a big box with nosecone and aluminum fenders.. . starting to really look like a car now!

Here are the fenders and nosecone mocked up in place


Gives you an idea of how the frontend will look:


Got the framework for the scuttle/dash assembly welded in place. This will be removable for instrument maintenace & replacement.



A view of the rear fenders and some of the diagonal bracing I put in:


Rear suspension.. still working on getting the geometry correct for the rear shocks. Getting close:


Rear view of the car:


Hand bent these peices to complement the arch of the rear fenders:


Also hand bent these corner peices. Not bad considering I just used a hammer and a peice of tubing to bend it around:



Better view of the diagonal bracing. The backend of the car is starting to look like a birdcage with all the tubing:


This car is WIIIDE.. 68" width edge to edge on the rear fenders:



The nosecone needs a lot of work to fit. I may have to do some work on it to allow for the taller engine.


Yummy:


Here are the upper balljoint brackets I fabbed up for the fronted. Still debating on whether or not to redo them. After I got it together, I realized that the kingpin inclination is around 15 degrees. If that causes handling issues, I'll redo it to move the heim mount upwards and outwards a bit:


A view of the dash peices. They look pretty uniform. Took a lot of minor adjustments before I was happy with how they looked.


The Seven and the 510:

Is that a modified 240SX front upright?

I was going to mention the inclination issue... all you have to replace those tabs with ones carefully angled to center the ball joint's travel. Even then it's going to be close. Move your suspension through its full range and check!

_________________
Midlana book: Build this mid-engine Locost!, http://midlana.com/stuff/book/
Kimini book: Designing mid-engine cars using FWD drivetrains
Both available from https://www.lulu.com/

it is a stock 240sx knuckle, turned around backwards. The tie rod will be mounted on top of the arm to negate the built-in ackerman.

The rear uprights are fabricated from scratch.

The heim for the upper balljoint was just sitting in that position when i took the photo. They are 65 degree units which would require the A arms to be at a 32.5 degree angle up or down from center in order to bottom out. That is well outside of the motion limits of my shocks, etc, so it isnt an issue. When I relocate the heim mount, I'll align it with the expected position of the A arm at ride height, as I did with this first attempt.

I have a pretty good idea of how to fix the inclination issue. It really wont be that big of a deal. I'm going to leave it as-is for now and deal with it at a later date.