My Miata/MX5 project

[jmc14]

Hello. I am an avid car guy and love the 50's Sport racers. I have been fortunate over the past 13 years to be able to build a nice kit car and some cars of my own design. Up until now I have used Corvette suspension and drivetrains.

A few years ago I purchased a Miata(MX5). I fell in love with it. Simple, Fun, and inexpensive. I decided that my next project would use Miata parts.

I was going to simply unbolt the suspension cradles and transfer them, along with the stock drivetrain, into a space frame that I would build. I purchased a body with this intent but it didn't work out.
I then tried to strip the body off of the Miata and design a 50's inspired body that would simple go over the Miata tub.

I kept running into a problem. The Miata's engine is mounted fairly far forward and it's tall. The fuel tank hangs in front of the rear suspension which pushes the seating position forward. I like the long, low bonnets and the short, rear seating position of the old cars. It's difficult to get the look i want by leaving the Miata mechanicals in their stock location. In addition I have long legs so added foot room would be great.

Recently I was able to purchase a 1958 Devin inspired body. I love the Swoopy look. I decided to build my project using this body as a starting point.

Here is what I am doing and my goals.
-1500lbs target weight.
-54% rear weight. (This is what I found that I like)

I have almost completed building my space frame. It has a 93 inch wheelbase. The Miata cradles bolt in. But, I moved the engine rearward by 12 inches from the stock location. The engine is still tall and I have to have a bulge to cover it. But, it helps with weight distribution and I can have the bonnet taper more quickly to the front.

The frame wraps around the occupants. It is 20 inches to the top of it. The doors will be functional. But, only the top half will open. The seam line will line up with the bottom of the full tilting bonnet. I like total access to the mechanicals. Unlike some cars, my bonnet will have a rear bulkhead. This will keep the shape true. I have done this with other cars with great success.

I am using a Porsche 356 Speedster windshield. It's the perfect fit. I think that it looks good. And, it's legal in the USA.

Here is a picture of the work in progress. Lots to do. More mods to come. Having fun, John

[JG]

Great work going on, congrats. I hope you keep the thread going with lots of updates and pictures, love this sort of creativity.

John

[jmc14]

I'm not sure about the center engine bulge. So, today I took it off and mocked up what it might look like with a different bonnet design. Any opinions on which direction would look best?

Tomorrow I clean the shop!

[JG]

I prefer the cleaner lines of the bulgeless bonnet, more retro 50's.

[jmc14]

Thank you for the comments John. I agree, I like the bonnet with out the bulge.

Here is a picture of my frame in progress. This is a test "mule" for concept and fit. It is not the final one and it doesn't have all of the bracing or end caps, ect. Also, I'm not a welder. Once I have the frame where I want it a friend of mine that builds race car chassis builds the final version for me.

Having fun.

[jmc14]

Here is a quick photoshop with the wheel arches rounded and a Jag inspired bonnet bulge. I like it. Now off to the shop, which needs a good cleaning!

[ra5ax]

Hi mate,

Im right in the middle of a similar project where are you based, Have you looked at the suspension supports yet? Its the one area Im very wary off..

Over the past 10 months I have learnt that the TVR Cerberal chassis almost suits the Mx5 perfectly have a look at this link it helped me look into the areas for strength and handling.

few images of my build in process on in my threads if your interested

Like the body by the way prefer the unscooped though

Andy

[jmc14]

Here are a few pictures of the almost completed frame. It combines the elements of a backbone frame with a space frame. i like sitting inside the frame. At ride height it is 24 inches to the top of the side rails. Making progress.

[ra5ax]

looks pretty similar mate atleast thats given me a bit more confidence.

one query whats your engine height floor to top of engine i think mines sitting a little high.

Still a lot of strenghening to go into mine but at least were on the same line of thinking.

[Kit Car Splined Hubs]

This car needs wire wheels to really set it off. Ever thiought of having them?

[jmc14]

Yes, I've looked at wire wheels. I agree that they would look great. The problem with them is that they are very heavy. The Miata suspension is very sensitive to wheel weights. For best performance it's important to use a light wheel. If looks are the priority they would be a great way to go.