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This weekend, I got the Upper A arm brackets tacked in place on the chassis and started working on positioning the brackets for the front inboard coilovers. Spent a good 3-4 hours just tinkering around with peices of steel, the shocks, heims, and other parts I had laying around to see what would work and what wouldnt.

What I'm aiming for is to have a setup that will allow me to alter the rocker ratios if needed, so I had to have plenty of room around the rocker assembly. I also had to come up with a reasonable way to mount the rockers to the chassis without a lot of complicated tubing work, yet still allow for a very solid mount. I also had to to make sure I had enough room around the shocks to properly fit the steering rack in place and have enough room vertically to adjust out any bump steer. Its quite a task to make everything fit in what little space there is up front.

Finally!! ... An update!

Tonight, I went to work on the problem of the front shock mounts. I had to figure out where the shocks are going to sit up front, yet allow the needed space for the mounting and motion of the pushrod and bellcrank... AND allow enough room for the rack and pinion and other needed items.

Here's what I came up with, along with some newer photos of what the frontend looks like now. Also got some photos of the new Woodward rack that showed up on my doorstep last week:

The frontend as it sits after tonight's work:


Suspension is starting to take shape. You can see one of the rockers on the right side of the chassis:


Details of the suspension. I have all the brackets tack welded to the chassis now.


Final placement of the lower coilover mounts.


I custom fabricated these brackets with a little beer-box prototyping work and the plasma cutter. Took 1 hour from start to finish for the set. They are different front and rear due to the chassis width changing, so it was a bit of a challenge to get them right.


Looks like it should work. I have room to change the rocker dimensions should I need to alter the motion ratio.


Top down view:


Top down (front of chassis is up in the photo). Lots of room between the shocks!


With new steering rack mocked up in place:


It'll probably sit just a hair lower than this photo:


End of rack looks good for bumpsteer.. I'll be running the steering link off the bottom of the rack end to allow it to drop down. This will let me orient the rack a little higher to clear the nitrogen canisters on the shocks.


Its snug, but I think its entirely doable!


The new rack is a real work of art:


You can see how the unit is opened up to change the steering ratios:


Woodward Precision, indeed..

Nice! Those shocks look like they fit perfect there, but will you be able to reach the adjusters very easily once the car is together?

It'll be a challenge to get to the adjusters, but I'm pretty sure I can do it. It'll probably be easiest to get to them from underneath the car. Haven't thought about that very much yet. They will be accessible. I'm planning on making the bodywork on either side of the nose cone removable somehow to help with adjustments and pre-drive inspections. havent quite figured out how yet.

Looking good! That's some real tedious stuff but take your time. It will be worth it in the end.

The front suspension is done and it works!!!

Fabbed up the rocker mount brackets today and got the front suspension pretty much done.

Here are the brackets I made:



This side is actually sitting on its own after I got it all mocked up:


The rocker in place.. perfectly straight shot to the pushrod mount at the wheel.


Here you can see that at ride height (left), the shock is compressed about halfway, which is right where I wanted it.


A couple more views of the rocker assembly:



A shot of the whole frontend.


I have decided to change over to the 2003-2004 Yamaha R6 shocks in the front, which puts the nitrogen canister parallel to the shock body. I decided this after looking at the clearance between the pushrod and my tie rod with the rack and pinion set in place.. it looked way too tight of a fit. I figure that I can move the rack forward if I go with the later shocks, as the only thing in the way is the nitrogen canister, not to mention this will give me springs that are the same, left to right. The r6 shocks I have now have different springs on them for some reason.


Here is one of the 2003-2004 R6 shocks:

When moving the rack, you should think about moving it back, not forward, if possible (this provides Ackerman angle). We're moving our racks back an inch to provide some Ackerman, as we had our tie rods in line with the rack. Gives way better steering, particularly at low speeds. Easier on tires, too...

The rack will definitely be located rearward a couple inches. The reason I want to move it forwards a bit by changing shocks is that it may be TOO far rearwards at the moment. I'd like to sit it about 2"-2.5" back from the knuckle arm ends.

Yesterday, I got the new 2005 R6 shocks in place in the frontend and got the whole frontend supported by the suspension.

I did a spring rate test to check the rate at the wheels. Standing on the frontend, with my 200lb, it drops 1/2", which equates to a 200lb/in rate at each wheel. This seems about perfect!

I started work on finishing up the rear suspension and related parts. The rear differential mount that I'd previously done, I wasnt happy with, so I pulled it out and went to work redoing it using some polyurethane leaf spring bushings, which should be a little more suited to the shock loads that it'll see.

Also managed to get the fuel cell mounting brackets welded in place and drilled to mount the cell.

I'll take some photos and get them posted up today if possible. All in all a productive day.

Ok!! Pics!!

Found a cool sticker in the garage that begged to go on the fuel cell:


The new rear toe adjuster tubes came in today (I had to use the old ones to make the upper A arms for the front suspension):


Here you can see the fuel cell mount as well as a bit of one of the diff mount bushings (in front of the fuel cell). I'll get better pics of the diff mount when its done.


Here is how the front of the car is sitting. It is sitting on the suspension in this photo:


Its looking mean!


New 14" steel adjuster tubes for the pushrods. Right now I just have some scrap conduit working as the pushrods to roll it around the garage.


Shiny new 2005 Yamaha R6 shocks!


Here is the new and improved layout up front with the newer shocks. I really like how these turned out.

Looks real good.

Pics from this weekend's progress..

This weekend, I decided to tackle mounting the rear hubs to the custom uprights. I also acquired a set of new front and rear rotors for the car, so I can start working on the braking system.



In order to drill the holes to mount the hubs, I decided to sacrifice one of the rear hubs I had "for the cause". I used the plasma cutter to take a notch out of the wheel mating surface to allow me to drill out the threaded holes with my drill press. Once all 4 holes were drilled out to the appropriate size, I just placed the hub on each of the uprights and used the hub as a drill template for each of the holes. Worked great!


Here is the final result:


Both of the uprights, side by side:


Once the hub was bolted up, the rotors went on for a test fit!


The upright I made is a bit thinner than the original, so the original bolts protrude a little from the front side of the hub. Should work fine though.


Now, here is one reason why the 240sx rear brakes will work well for a Locost build... The brake caliper and parking brake are one assembly. The parking brake bracketry looks like it'll work really well with the Locost chassis and wont interfere with anything.


Another view of the brake caliper. You can get an idea of the bracket that needs to be made to secure the caliper to the upright.

Your build is looking fantastic, John, I'm really looking forward to seeing it out sometime ... hopefully mine will be ready about the same time and we can drag race 'em ...

-Steve

Hi Steve!

I think you'll probably beat me to the street. Though my chassis is close to being on its feet, I still have a lot of details to work out regarding the steering, braking, and other systems.

Bit by bit.. mine's taking shape, but I think I may still have a long ways to go before its drivable.

Having said that, let me know when yours gets close.. would like to be present for its maiden voyage.

Just scored this stainless steel turbo manifold on ebay.. seems to be a better one than most I've seen for the ka24de.. Its designed to take a standard SR20det t25 turbo.




Scored it for $100, which is cheaper than I can make one for.

Whether I go turbo or not, this manifold will let me get the exhaust out the side without interfering with the brake and clutch master cylinders.