Is the Answer a $100 supercharger?

Please let me introduce myself. I'm Jack Heideman from Holland, Michigan. I go to Hope College for Mechanical Engineering, I'm on the Formula SAE team, and like to work on cars in my free time.

Now to introduce my car. I bought this 1992 Miata two years ago as a winter beater. It is really rusty and almost everything that could have gone wrong with this car did, but I learned a lot fixing it and have had a lot of fun autocrossing it the past two years. Since I bought it, I've replaced the engine, gearbox, swapped in a viscous limited slip, added Konis, RE71Rs, and a big front sway bar. I'm obviously upside down in this thing, but I'm having so much fun it's worth it. I can always pull the good stuff off if I find a better shell.

My dad (Carl Heideman) has built a supercharged MGB and TR6 that he's written about in GRM and CMS. They always impressed me and I would like to have my own supercharged car. I looked for some used Jackson Racing kits but they are all a little out of my college budget. I learned a little bit about fabrication when I was younger so I figured I could build my own kit for my Answer.

I watched craigslist for a couple months and found a Mercedes M45 for $200. After about a month of the blower on craigslist I offered the guy $100 and he took it. Here it is:

When I brought it home I was pleasantly surprised by how clean everything was. After more inspection it seemed like the blower was just rebuilt and never run. Here's a picture of the clean rotors:

I mocked the M45 up in the engine bay of the Miata using some wood blocks and a 2.5" tube to simulate the outlet. It looked possible to make fit under the hood.

As far as the ECU goes, I recently installed a Megasquirt PNP to learn a little about tuning an engine. I'll just have to retune the car once the blower is on. I would like to see around 6-7psi to start with. I haven't figured out how i'm going to deal with changing the pulleys to get my desired boost yet.

My next step is to start making mounts and CAD up an intake base--stay tuned.

Really liking the start of this, my dad and I have been wondering if we should turbo or supercharge our Miata, kinda exactly like you are, keep up the good work.

This makes me happy.

Carry on.

We have royalty amongst us!

Been of fan of Eclectic probably since before you were born. I have no doubt that this will turn out quite well.

In reply to Jack Heideman:

I have a Jackson Racing kit on my Miata. The supercharger is an MP62 and sits right where you mocked up yours. Outlet side is up, and about 30 degrees from horizontal. The inlet is kind of convoluted to get to fit in the space between that board and your strut bracket, but it can be done with some appropriately sized tubing, metal or plastic plumbing. Although , I suspect you're probably pretty handy at fabricating whatever you need.

Subscribed for future updates!

after you finish this project I have a cheap thunderbird supercharger that was destined to go on an S52, you might as well tackle that for your e30 next

This is relevant to my interest

that's really cool

Heideman anything .....I'm in

Fun project!

M45 on a 1.6 is an old recipe, so you shouldn't have to reinvent the wheel too much. Just don't try to push it much past 6 psi. You'll hit the limits of the blower at that point, so while you might increase the boost further you'll get such a drop in efficiency that it'll all go to hell. Also, make sure you have an air temp sensor that can handle over 200F.

Thanks for the encouragement everyone!

Keith, I never thought of looking into the IAT sensor range. I'm using a GM open element sensor. Thanks for the advice!

DeadSkunk, I have been looking at a lot of pictures of the Jackson Racing kits. Unfortunately I don't believe I'll be able to replicate their castings out of sheet metal so the packaging might be a little tougher. Hopefully I can figure it out.

I'm not going to lie. I have been VERY tempted to supercharge my little 924 now that it has a bunch of room under the hood. Going to have to follow this because budget boost builds that are well done fascinate me. There's a local guy (not sure if he's on here) who ripped the drivetrain out of a CRV, cut things to pieces, and converted his little honda into 4wd, on top of a budget supercharged/turbocharged build. It is one very interesting project, and a fast one.

So stuff like this gets my attention. Keep us boosted! I mean posted!

Are you planning on intercooling it?

At 6 psi, I wouldn't. Adding an air/air intercooler increases the throttled volume and introduces a bunch of driveability problems. Air/water in the manifold is a lot more effective but more complex/expensive.

I'm not planning an intercooler at first. I was thinking about an intercooler later down the road, but thanks to Keith's input maybe a different route is better.

If you keep your goals reasonable, this will be a good setup. If you start chasing power, you're going to end up banging your head against the wall fairly shortly. For 160 rwhp, it's pretty happy. I had one years ago.

If you don't think 160 rwhp is going to be enough, it might be a good idea to determine that now and maybe build in a different direction.

It's fun to see a DIY SC build. They're a different set of challenges than a turbo.

I would honestly be happy with 140 at the rear wheels. This is more just a fun project for me to learn a little about superchargers, tuning, and make my 1.6 a little more fun. I bought the old GRM Turbo Miata project car last fall and I don't need this car to be anywhere as fast as that one.

Neat! I look forward to seeing how this works out, especially the custom inlet. I put an m45 on my '99 a month ago but that was amateur hour - it was the kit meant for a Miata, with literal step by step instructions. Yours is way more interesting :D

Here's an update:

I started working on the inlet/outlet for the blower. If I were to do this as my dad taught me, we would have made a template out of cardboard and then cut it out of steel with a cutoff wheel. However, I thought I would take advantage of my school's resources. I measured the gasket from the blower intake and drew it up in Solidworks. I printed the drawing, cut it out, and test fitted it. After a few tries it fit well on the supercharger.

After the paper copy fit well, I used the school's 3D printer to get a better model.

Here it is on the blower:

I'm hoping to use the Engineering Department's two axis plasma cutter to cut the final one out of steel.

The great thing about a supercharger is that the power is ALWAYS there.

Neat project. Looks like you're off to a great start. May I suggest you build the manifold and charge pipe out of aluminum instead of steel? It'll be much lighter, plus you don't have to paint it. Enjoy this time of your life. Some of my best memories involve being in engineering school, being involved in designing and build our SAE car and learning how to TIG weld, all at the same time.

mbruneaux wrote: The great thing about a supercharger is that the power is ALWAYS there.

...as long as you're spinning it fast enough but not too fast

So you're saying we need a roots type supercharger driven off a moped CVT geared in reverse?

Keith Tanner wrote:

mbruneaux wrote: The great thing about a supercharger is that the power is ALWAYS there.

...as long as you're spinning it fast enough but not too fast

I always wondered how a centrifugal supercharger would work out on a 1.8 miata. Seems like a better march due to rpm ranges involved, but i always see rpots style. Has to be a good reason why.

This is awesome. When I was in college I was messing around with a '77 Suburban and attempting to assemble several boxes of parts into something resembling a '71 BMW 2002.

You kids these days. Sometimes yinz give me such hope for the future. sheds a tear