Introducing Midix: the scratch built mid-engine sports car

[Miatav8,MstrASE,A&P,F]

Interesting link. I guess those are priced individually but probably better quality than the ebay kits with the junk upper seat and very high rate.

You could go back to your original UCA adapter and coilover but offset to reduce the amount of UCA offset needed outboard of the chassis.

I’m not sure the oem rear brake system cable routing is enough of an issue to create the toe link issue. Have you considered swapping only the rear calipers from side to side to change the cable direction? That appears to solve all the problems.

Also, oem cable tend to be too long in a locost so the wrong direction can be beneficial. They should also cross to the opposite side to increase the radius of the cable bend before being tee'd to the main link/cable from the ratchet mechanism.

[mainlandboy]

Have you considered swapping only the rear calipers from side to side to change the cable direction? That appears to solve all the problems.

Also, oem cable tend to be too long in a locost so the wrong direction can be beneficial. They should also cross to the opposite side to increase the radius of the cable bend before being tee'd to the main link/cable from the ratchet mechanism.

If I swap the rear calipers from side to side without swapping the knuckles, the calipers will still be mounted towards the front of the car, which will still have the caliper connection for the parking brake facing the rear of the car.

In a Locost, the seats are right in front of the rear axle, so having the parking brake cables cross over to the opposite side and attach to the calipers from the rear/wrong direction can be a good way to use up the length of the long factory cable. In my mid-engine car with the seats pushed forward to fit the drivetrain between the seats and the rear axle, I suspect that the factory cable won't be long enough to do this, which is why I was going to swap the knuckles side to side (to allow mounting the calipers to the rear), but keep the factory rear calipers on the sides they are made for. Without the parts in hand and laid out in the correct location though, it's hard to say which method will work best.

Decisions, decisions!

[mainlandboy]

For the sake of simplicity, I decided to ditch the idea of converting the MacPherson strut suspension to double wishbone in the rear, and simply replace the factory strut assembly with an aftermarket adjustable coilover. The aftermarket coilover will allow for adjustment of ride height, spring pre-load, damping, and camber.

[mainlandboy]

Another small update: I created a CAD model of a 3rd generation Miata muffler and added it to the chassis assembly. The Honda R18 engine has the catalytic converter bolted to the front of the head, with the outlet pointing down. The exhaust will wrap underneath the engine and enter the muffler, which has the intake in the middle of the canister, and the outlets on the ends of the canister.

[mainlandboy]

Got a bit more CAD modeling done. Added the following:
- Steering shafts and U-joints to connect the steering wheel to the steering rack
- Brake and clutch pedals and master cylinders/reservoirs
- Front bumper (likely needed to pass safety inspection)
- "Frunk" paneled front trunk storage area

[Kinetic Research]

Your design is progressing nicely, the devil sure is in the details. How would you feel about putting some form of crossbracing in the main roof hoop? Will add a lot of roof integrity.
Cheers
Marcus.

[Impulse33]

Super excited to stumble across your build! I happen to have a 9th gen civic that I haven't been using much due to working from home.

The site looks fantastic as well!

If I were to try to follow in your footsteps, would you recommend that I pick up the midlana book?

[mainlandboy]

Your design is progressing nicely, the devil sure is in the details. How would you feel about putting some form of crossbracing in the main roof hoop? Will add a lot of roof integrity.
Cheers
Marcus.

Thanks Marcus! Putting some cross bracing diagonally through the main hoop would certainly help with the rigidity, but I'd prefer to keep the opening formed by the main hoop visibly unobstructed. I would be less opposed to add some cross bracing in the opening in the roof though.

[mainlandboy]

Super excited to stumble across your build! I happen to have a 9th gen civic that I haven't been using much due to working from home.

The site looks fantastic as well!

If I were to try to follow in your footsteps, would you recommend that I pick up the midlana book?

Thank you very much for your compliments! The cost of the Midlana book is quite high, but the amount of content/detail in it makes it a very good value for someone who wants to recreate a Midlana of their own. If you plan on building a mid-engine car from scratch, I would say that it is still worth getting the Midlana book, even if you plan on deviating from the Midlana design as I have. The overall frame and suspension design are the main deviations of my Midix from the Midlana, so those are the details that are different from the Midlana book.

Eventually I will get around to creating/sharing dimensioned drawings of my Midix frame once I have physical parts in-hand to verify fitments, but that will likely be a few years out as I don't have the time/space to start this project yet.

[mainlandboy]

I updated the website to describe how to lock the Civic steering rack in the center position, allowing the factory tie rod ends to connect to the Civic knuckles to control the rear toe alignment. Here is a link to the page:

https://midixsportscar.wordpress.com/re ... nd-brakes/

It's not the most elegant solution, but it is a simple and cheap solution.

[Miatav8,MstrASE,A&P,F]

Another option is to weld the heads together of a 75mm bolt that fits the outer tie rod and a 3 inch bolt that will fit a common female rod end and jamb nut. Mount the rod end. If the rod end and bolt are left hand thread, the adjustment will not require disconnecting the rod end from the chassis.

If the rules say you can't weld, tap each end of thick walled dom as needed for studs outboard and male rod ends inboard.

[mainlandboy]

Thank you for your feedback! What I like about your solution is that it gets rid of the bulky steering rack that is just adding unnecessary weight.

Another solution would be to replace the Honda steering rack with a lighter "dummy" rack which is simply used as mounting points for the inner and outer tie rod ends. This is what is done on the DF Goblin kit car:

[mainlandboy]

Small update: I moved the radiator from in front of the frame front tubes to behind the frame front tubes. This allows access to check and fill the radiator from under the hood without having to remove the nose cone. I had to move the front frame tubes forward slightly to make room to fit the radiator between the frame front tubes and the steering rack. Pushing the front frame tubes forward also meant redesigning the front bumper to sweep backwards on the sides so that the tubes in front of the tires are not too far forward.

I also moved the radiator fan to the back of the radiator, as I've read that a "puller" radiator fan is more efficient than a "pusher".

[mainlandboy]

Created some updated renders of my CAD model.

[mainlandboy]

I bought a 3D printer a few months ago and decided to make a 1:10 scale model of my Midix design.