Engine Rebuild - Part 2: Engine Mounting and Dissasembly

Now we are getting to the topics that I really wanted try to cover more in depth. Anyone can take an engine out of a car and take it apart, but getting it back together and getting to to run, THAT MY FRIENDS is a challenge.

I covered this in the engine removal post, but I rebuilt my engine because my crank bolt was loose and had chewed into the keyway a little bit. Mine was no where near as bad as other I have seen on the internet. I do believe it was bad enough that I was running 1-2 degrees retarded timing. I can't currently confirm this because I didn't think that was the problem at the time and I took it all apart and didn't want to put it back together to check it with a timing light. But I will say, while I am not the best driver in the world, I was being beaten by completely stock Miata's at autocross events by ~4 seconds depending on the course. So we will see if this helps liven up the motor a little bit and help with that.

If you have a worn out keyway, one option to fix it rather than take the whole engine apart and replace the crankshaft like me is to use Loctite 660 to repair it. There are plenty of walk-throughs out there that show you how to do this. Loctite 660 is specifically made to repair bad keyways in machines and people seem to have good luck with the fix if yours isn't too worn out. My engine was a good candidate for this fix, but now that I plan to turbo I was going to replace the piston rods anyways.

Lastly, before we get into it, if you want to rebuild an engine but are afraid of tackling a project like this, it really isn't that bad. If your car is a fun car and isn't needed for daily driving or anything like that, I highly recommend picking up a Grainger Manual (or similar) and learning something new. This book walks you through how to rebuild an engine and is a great resource for plenty of other maintenance things. On top of that, if it is a miata you have, there is no better car community out there willing to help people solve problems. You are all wonderful people and I thank everyone who has helped me get my car to where it is today!

Preparing the Engine for Work

You are going to want to clean the engine as best you can. As the parts come off you will be able to clean them better, but it is helpful to start with a clean engine. Use some engine de-greaser, a brush, and a hose to clean off what you can. Of course mind the electronics when you do this. If you didn't already do it in the car, while the engine and transmission are on the hoist, NOW is the time to drain the rest of the fluids and let it sit for a little. 

In usual Ray fashion, I didn't take any pictures of this process, but next you need to unbolt the transmission and put it somewhere. The thing ways ~60lbs, it is pretty easy to carry by yourself, but as always have a second hand or set it up on something in case you have problems. Next is the flywheel. This likes to spin while you try to get it off. Use either an impact gun, or a decent sized flat blade screw driver and put one of the transmission bolts back in for leverage to hold the thing. You should now have access to the back of the engine to mount it to the engine stand.

Engine Mounting

First thing is first, you need to get the engine somewhere that you can work on it. I had an engine stand and I welded up some fingers to use to attach it since the originals fingers were missing from the stand. If you want to make your own I used:

• 1" x 1" x .120" low carbon tube ( I got 3' and had just a little left over)
• .625" x .065" Tube (Got 1' of this)
• M12 x 1.5 x100mm bolts (This ended up being a little long 90mm would be better)
• M12 x 1.5 Nuts and Washers

I am going off memory about this as I don't have them right in front of me right now, but I believe I cut (4x) 6" sections of square tube. I drilled them to .625" so the tube would slide through. I then cut (4x) 2" sections of the round tube and slid them in and welded them. I then marked the hole locations for the plate that was on the engine stand and drilled them out. Then I bolted it all together as seen below. I may have made adjustments from what I have above, so double check your work as you go through this. 

Removing External Components

Next is to start removing everything still attached to the outside of the engine. Depending on what you took off with it still in the car this might vary. But I had to remove things like the intake manifold, fuel rail and injectors, EGR components, misc brackets. This part is easy to do and because of that it is easy to do it quickly and forget to label stuff! LABEL EVERYTHING AND TAKE PICTURES OF EVERYTHING. I was trying to be really conscious of this while I was removing stuff, but as I put it back together there have been plenty of mystery parts that have taken a fair bit of time to figure out where they go.

A smattering of the photos I took

Remove the Rest!

With all the external components off you should have a basic looking engine with an oil pan, block, cylinder head, and valve cover, plus or minus a couple of things. Start by removing the valve cover. The Grainger manual recommends starting in the middle and spiraling outwards to loosen AND tighten the bolts. While I can see this for tightening them, I am not sold on it for loosening. But DO IT ANYWAYS, it surely won't hurt. 

With this off you will be able to see the bolts holding the cylinder head on. Do the same process as the valve cover. Start in the middle and spiral out to loosen these and take the cylinder head off.

You should be left with something like I have shown above. I will not be covering how to adjust the valve lash and stuff for the cylinder head as I had someone do the work for me. It was ~$275 to get the valve seats re-cut, the valves ground, seals replaced, lash adjusted (with the stupid shim type system), gaskets replaced, head checked for flatness and re-milled, and likely a couple other small things I am forgetting. If you want to do it yourself, great! But I recommend letting someone who has done a ton of them do it for a reasonable price unless you have the proper tools.

Now we turn the engine over to get the oil pan off. Remove all of the bolts around the pan. Using a small screwdriver or sheet rock knife, break the seal of the pan to the block. HERE IS WHERE THINGS CAN BE TRICKY! Mine was so covered in sealant I couldn't see where it was, but there is an oil baffle that gets sandwiched between the oil pan and the block. When you break the oil pan free, if the baffle is still stuck to it, you won't be able to get the oil pan off. It will seem loose but something 'springy' will be keeping it held on. If this happens DO NOT PULL ON THE OIL PAN! YOU HEAR ME! You will need to take you knife and cut along the sealing surface of the pan to try and cut/pry the baffle off of the oil pan.

This is the baffle and the block still together. The oil pan sits on top of the baffle and sandwiches it between it and the block

The baffle is bolted to the oil intake tube, which is why you don't want to pull on it too hard. If you do, you risk bending that tube which you will then need to replace. 

Remove the Crank, Pistons, and Oil Pump

BEFORE YOU DO ANYTHING, take 4 paper towels and label them Cyl #1, Cyl #2, Cyl #3, and Cyl #4. If you plan on re-using any of the internals, you need to keep track of where they all go, If you are replacing everything, then this part is good to still do in case something goes wrong and you end up needing something. With the engine still flipped over, you now have access to the crankshaft and main bearings. Rotate the crank shaft to some point where you can access all the rod end caps.

Take a punch and punch the bottom of the end caps with a dot(s) for what the cylinder number is. 1 dot for cylinder 1, 4 dots for cylinder 4. With this done you can now loosen and remove the end caps, putting them and their bearings on the respective paper towel. CAREFULLY push the pistons down to a point where they are out of the way as you will likely not be able to get them out at this time.

Loosen and remove the crankshaft main bearing caps. These should all be labeled and with an arrow that points to the front of the engine. Double check and remark if you are uncertain about the markings on some. Make sure to get the thrust washers off of the fourth main cap. With these removed, the crankshaft is now loose and can be carefully lifted out of the engine. Make sure not to scratch the journals on the piston rods or anything else. 

With the crank out, you can now push the pistons the rest of the way out. There is likely carbon build up on the top side of the cylinders. This may need to be cleaned off with some carb cleaner and elbow grease before the pistons will slide out. Remove the oil sprayers that are on the bottom of the cylinders and keep them with the correct cylinder. Mine had no copper washers, but it seems like the pre-NB 1.8L engines had them.

If you have not already, remove the oil pump.

Using your punch, mark the piston rods and the bottom side of the pistons in the same fashion as the bearing caps for the cylinders that they correspond to.

You should now be left with an empty cylinder block ready for work! The coming post after this one will be about putting it all back together. MERRY CHRISTMAS TO ANYONE READING THIS TODAY!

Engine Rebuild - Part 1: Removal

Alright everyone, the time has come! I am yanking all the is beautiful and right in the world out of this car. With a little patience, a book for guidance, and a second hand from my dad; we got the engine and transmission out of the car in about a weekends worth of work. I have been using the Grainger manual for the removal and rebuild of the engine. Overall it has been a great help and I have only found a couple points where it was lacking on information which were easily solved by the internet.

This is the one I have. It says it covers to 1999, but it doesn't really cover the modifications to the NB 1.8L. It uses the 1.8 out of the NA. Which not much is different but there were some little differences along the way. Grainger Manual

Drain all the fluids and remove the radiator. Supposedly you can get it out with the radiator in, but I wouldn't risk it.

Label Label Label...oh yeah and Label

I think the book does a good job of covering how to get the engine out so I am not really going to cover it. I will say that if you do have an NB and use that manual pay attention to stuff because things are not all the same. Such as the NB has the cam sensor in the front of the engine, not the rear; or the fact that the oil sprayers under the pistons don't have copper washers on the NB but do on the NA. MY ONE RECOMMENDATION IS (this isn't how the book does it), to remove the transmission, unbolt it from the Power Plant Frame (PPF). Leave the PPF attached to the car. There are other engine write ups that cover this and I highly recommend it. It was surprisingly very easy.

Make sure you get a hoist with a long enough boom to not hit the bumper

LABEL EVERYTHING AND YOU CAN'T TAKE TOO MANY PHOTOS! Since I have not put mine back in, I can't say how good a job I did. But I know it will not be good enough because there are always questions, like "why the hell would I label this that!?"

I don't want to put them all in here, but I have been compiling a mass photo collection of the rebuild. I have been trying to document little things that aren't obvious, or simply just trying to get pictures of things I had questions about that no one seemed to have good images of. So if you are looking for a picture of how a bracket goes or something, you may browse through. I have a bunch of different picture that will hopefully help someone.

My photo dump can be found here: http://imgur.com/a/I6Q7W

I am thinking my next entry will be disassembly. 

Sizing the turbo

Sizing a turbo can seem like a daunting task if you have no clue where to start. I didn't when I started looking, but a little research can go a long ways. This first thing you need to do is familiarize yourself with how to read a turbo compressor map. The Garrett website has some really good documents about turbo charging and what all that junk on a compressor map means.
I recommend starting there as I will be using most of the information on this page:
Garrett Turbo Tech Information

"Okay, I skimmed through this and didn't really pay close attention to it all cause words are hard." Boy random person I couldn't agree more! But I highly recommend you take your time and read it to fully understand everything. I am not necessarily going to hold your hand through this as I think it is extremely beneficial to have to put forth effort to understand something. If you do, you will remember it for much longer.

"Alright, for reals, now what?" Now we have to do math. "OH MY GOD READING AND MATH, WHAT IS THIS? SOMEWHERE WITH A GOOD EDUCATIONAL SYSTEM?" Lucky for you guys I have a spread sheet that I am willing to share that will do pretty much all of the math. I encourage you to double check my math as I am not perfect.

https://turbobygarrett.com/turbobygarrett/compressor_maps (all rights reserved by Garrett for this image, it is not mine)

So on that compressor map we have the x-axis and y-axis which are mass flow and pressure ratio respectively. We are going to generate some points based on the engine to help figure out where on the compressor map our turbo will run for various RPM and boost values.

Really the only thing we need to calculate is air flow through the engine at given boost values and RPM as it is dependent on both. This is actually very easily done using the engine parameters that can be looked up in the owners manual and PV=nRT. This is the ideal gas law if you are unfamiliar, but the one we use is actually just a little different. What we are going to use is PV=mRT where m is the static mass of air in a cylinder and that is what we are solving for. The variables are as follows:

P: Boost pressure in absolute, units of kPa
V: Volume of a cylinder (this should include clearance volume), units of m^3
R: Gas constant = 0.287 kJ/kg*K
T: Gas temperature post intercooler (or post turbine if no intercooler used), units of Kelvin

Determine an appropriate value for the temperature and boost pressure(again absolute). This gives you a mass of air in a cylinder. Breaking down RPM into RPSec we can determine the lb/min of air through the engine. Now using that same boost pressure, calculate the pressure ratio. This is PR = Boost/Ambient. I hate typing out equations on these things, so I will reference you to the excel document for all of them.

Now by changing the RPM value and recalculating the mass air flow for a fixed pressure we can plot something that looks like this:

Then we re-do it all for another fixed pressure:

What does this all mean? We want our operating points to be to the right of the surge line and to the left of the choke lines. The closer we are too the pool in the middle, the better the efficiency we get. So as you probably noticed, at redline and 12psi of boost I am to the right of the choke line. This is bad and I do not plan on operating the engine in that area. Even the 10psi and 8psi graphs are right on the edge. Luckily these are ideal calculations and I actually have losses working in my favor to keep me from running over the choke line. This turbo will work for this engine but it does not have much over head. So if I planned on going any higher than 12psi of boost, I would be seriously considering a larger turbo.

Here is another example I did for my dad's land speed racing bikes. They are 125cc honda engines that are turbo charged. Only problem is that no one makes a turbo small enough for them to make any real boost. He just got a new Garrett turbo (the smallest one they make) which says it is rated down to 100cc engines. I find this to be false. You can see on the chart below that we aren't anywhere near close to being to the right of the surge lines, even at 12psi of boost. This is a good example of a turbo that is sized poorly.

You now know the gist of how to size a turbo properly for a given engine size and desired boost pressure. It should be noted that Garrett says that a rough estimate can be made of 10HP for every lb/min of air flowing through the engine. This will give you an idea of what the engine will make at the crank.

Here is a link to download my excel sheet to help calculate all this. There are comments on most of it explaining how to use it. It also has a sheet in there to calculate injector size and fuel pump size once you figure out what your max air mass flow rate is.

Turbo Sizing Calculations

Did someone say TUUUUUURRRRRRBBBBBOOOOOOOOOOOOOO????

Well I have disappointing news. The keyway on the crank is toast(ish). When I bought the car the crank pulley bolt was loose. I tightened it up and continued driving it for the past two years. But my guess is the damage was already done. It was noticed at the last track day that my pulley is wobbling again pretty good. I tried to tighten the crank bolt only to find out it is still tight. So I ended up taking it a part and this is what I have:

The lower timing belt cover has been chewed up from all the wobbling

Broken key, this is supposed to be uniform and square along the whole length

My engine is a total oil and rusty mess

Damaged rank pulley piece (not sure what to call it). The keyway on the crankshaft itself which is the hard one to replace looks exactly like this too.

So there are plenty of people out there who have had the same problem and they fix it using Loctite 660 which was developed for the exact purpose of repairing worn out keyways. The only problem is, when people do this they basically glue everything together with the loctite, which I planned on rebuilding the engine this winter. I didn't want to glue it all together only to take it apart again. Sooooo, for the first time in my time of owning this car, it got trailered (back to my parents for winter). After all the abuse of autocross and track days of which I was sure it was going to break, it is my taking stuff apart that causes me to trailer the car.

Along with finding this out, I have been doing some thinking. It is going to take a lot of money to get this car road race ready. Then it is going to continue taking a lot of money. So rather than continually spending large wads of cash I don't have, I will spend one large wad of cash and see how much of it I can make my dad's money ;).

Oh you want to know what that wad of cash is going to? DIDN'T YOU READ THE DAMN TITLE! TUUUUURRRRRBBBOOOOOOO!!!!

I will still autocross the car, but in a new class. But most importantly, my HP goal for the car when I am done is in the 250whp department. This should be around the same wheel horsepower as my civic, motorcycle, and miata pre-turbo combined. As of writing this I have a pretty good grasp on the things that need to be done, so I will continue making posts with all my information for someone else to learn from my (hopefully) success.

Now I know what most of you are thinking because you follow my blog extremely closely and want all my latest information, "What about all that suspension stuff you were going to do and show us the magic numbers of testing". Well I still have intentions to do everything I said, this is obviously going to push everything back though. I might see about getting new suspension on the car while the engine is out, we will see. For now the future looks bright, broke, and boosted (don't be stealing my quotes now people).

I leave you with turbo gloriousness:TUUURRBBBOOOO

Racing Seat Bracket

8/23/16
I have since removed this bracket and gone to the PCI Sparco Seat Bracket for concerns of not passing tech inspection with my bracket. Info for it can be found here.


A couple weekends ago I went to an SCCA winter autocross event. Doing so I found out two things: A) I need some practice, B) My head with a helmet sits above the roll bar, which you know, defeats the purpose of it. So I spent the whole time in a sort of scrunched position as to not break the rules. After this uncomfortable experience I decided the next piece going into my car are a racing seat and a harness. 

For whatever reason I have always wanted a car with a racing seat and harness. It just makes me feel cool, even though I am sure it makes me look like a tard. Especially when it takes me a couple of minutes to get the harness on and tightened down. But boy do I feel cool. I put in a Sparco Sprint V seat with a G-Force 6 point harness. The seat fits well inside the car. The shoulder support barely sits against the door when it is closed, and the is mostly because my bracket came out a little skewed. 

For those of you taller people out there looking to race a Miata, especially if you put in a hard dog roll bar like mine, you will need a seat change of some sort and you will likely have to ditch the seat rails and go to a fixed mount. I am 6' 0" and as I said, with the OE seat all the way back and reclined, my helmet lies a good bit above the roll bar. A lot of the aftermarket seats come with simple bolt in options that can use the stock rails or supplied rails. The consensus on this seams to be though is it generally raises people up a 0.5". So I was set on getting a seat and making a fixed bracket system for it.

The first part of this was installing the hard dog harness bar. They make a bolt in harness bar for ~$150 for the shoulder straps. When you take the seat belt tower bolts off there are a bunch of spacers on it. The largest space is the same width and the harness bar mount. So remove that spacer then bolt it on. The only problem I have is that it locks up the rotation of the seat belt. This can be fixed by adding some washers to the assembly. 

The part I am most proud of for this seat is the bracket system that my dad and I came up with for it. I planned on re-using the factory seat mounts and the issue with that is if you want the seat right on the floor and all the way back you can't get to the rear bolts to tighten the seat down. So we took a piece of 1/4" steel and bent it to match the rear mounts. This then provides an opening underneath it which I intended to make a tab to slide under it to hold the seat in place. PRESTO,  you know have a seat the only needs the front two bolts to get it in and out. The rest of the bracket was made out of 3/16" thick by 1.25" wide steel plate. The tab that slides in to lock the rear was just a large piece of angle iron that we had sitting around.

When we were messing with placement of the seat we noticed it was getting caught on some bump that was in the back underneath the carpet. So we pulled up the carpet to find out that it was the plug for the narrow band O2. The seat was snagging on it and would go back or down anymore because of it. So I ended up taking it out of its mounting hole and just taping it to the trans tunnel to get me the extra space I needed. Worked like a charm. Just be careful not to yank the wires if you do this. 

Then came the seat bracket. I have a bunch of pictures of it, and next time it is out of the car I am going to take measurements and made a CAD drawing of it for people to use if they want to make something similar. 

The seat mount holes are at an angle and there is a hump behind them. We did some forming using a vice and a big ass pipe to get the pice to go over the hump and lay flat. To get the front cross piece angle I tacked it on each side and put it in the car and hammered it down to fit, then finish welded it.

So the bracket sets in the car and you slide it back to get the angle iron beneath the rear piece. The two hunks of round steel on the back were scrap we had and I welded the on the set the rear height of the seat. There is still some slop in the seat, you can rotate it some before the tab and the rear piece hit. To fix this I am going to take a thick piece of rubber and put a taper on it and glue it to the rear piece to make an interference fit so the seat doesn't move at all. If you go with something like mine, make sure to gusset the angle iron so it doesn't just bend and break at the weld.

I painted the bracket red and slapped it in. The seat is sturdy as can be and is really painless to get in and out of the car. I am really happy with how it turned out. Getting in and out of the car is more difficult now though. At some point I will take a picture of the bracket by itself and add it. 

Pro Car Innovations - Sparco Sprint V Seat Bracket

I somewhat recently purchased the passenger and driver side Sparco seat brackets from FRSport for the miata. I never felt like the bracket that I made was good enough to pass a real safety inspection as the seat could rotate just a little before the rear 'latch' hit the cross piece. So rather than design and make a new one, I went the lazy route on this. The PCI brackets looked well made and most importantly looked like it would get my seat low while still using the factory mounting locations. The only thing that you have to do for these brackets is, on the driver side only, hammer the trans tunnel in to make clearance. If you look at my post about the bracket I made, I had to do this also. This bracket requires more 'messaging' of the tunnel than what I originally did. But it was easy and I had no problems with a big hammer and a little patience.

I am happy to report that the bracket does keep me really low. I really don't think I can get my seat any lower without having to cut out the factory mounts and make my own. At which point I would still need space for the submarine belt mounts, so I could maybe get another 0.5". The adjustments on the side are also enough that I can get the bracket to work both for me and the lady friend (well close enough for her, we have to bolster her forward just a little extra so she can push the clutch in all the way). But considering I am 6'0" and she is 5'5" (This is a guess), the bracket offers a lot of adjustment.

I am writing this blog entry to show some tricks I have found on getting the seat in and out of the car. If you are short and have the seat mounted forward on the bracket, then it is very easy to bolt the seat to the bracket. Then put the whole assembly in the car and bolt the bracket to the car. But if you run the seat far enough back, like I do, you run into the problem of getting the rear bolts for the bracket in. Well then you have the option of bolting the bracket to the car then dropping the seat in and putting the side bolts in. This would be fine if there was some GOD DAMN clearance between things! You can make it happen but it is slow and frustrating. So below is what what I have found to work the best for getting the seat in and out. I can take the seat out and have it put back in under 5 minutes this way.

Step 1: Start with putting the two front side bolts in. Keep them loose enough that you can rotate the seat around them.

You need to be able to rotate the seat like this.

Step 2: If you have one, get the harness pieces out of the way.

Step 3: Bolt down the front of the bracket. You can make these tight.

Step 4: Rotate the seat up as far as you can.

Step 5: With the seat rotated up, you should be able to reach back in there and get the two rear bolts in and tight.

Step 6: It is still a little frustrating, but now put the two rear side bolts in. I find it easiest to use a ratcheting wrench to help make things go quickly. Tighten down all of the side bolts and you are good to go!

Easy as that everyone. Once you do this a couple of times, you will be able to get the thing in and out if needed in no time at all. Now time for TRACK DAY BRO!

Nothing like a track day with your bro's, even if your car is the slowest one down the straight

Eibach Suspension Upgrades

Hey everyone! I have some cool/good news! So this blog was just something that I started to kind of keep track of what I am doing to the car and potentially help people out doing similar things. As of right now I am averaging about 10 views a day. Woh Kanye, in another 5 years my posts are gonna be blowing up bigger than your ego/wife's butt/temper tantrums (take your pick). Why am I trying to make Kanye relevant again?

Alright enough about Kanye, time to get on to what this post is about, suspension upgrades. I have acquired some suspension components from the very friendly company Eibach. I have the Pro-Plus kit. This kit includes a stiffer front and rear sway bar, and a set of springs that lowers the car 1.3" and has a stiffer spring rate. Right now I have a full stock suspension setup. I also have a handy little accelerometer that I made using and Arduino. At my last autocross I used it to collect my max cornering and acceleration G's.

The data can be found in this photo album:
http://imgur.com/a/4oOUV

So we have some stock data, now what? Well I don't really want to put parts on, take parts off, put parts on, take parts off. My intent right now is to put the parts on one at a time and autocross/track the car and see if the max G's change at all. We are mostly looking at corning G's, but it will be interesting to see if accel or braking ones change with the changes. This is also a very simple A to B comparison. At some point I might be smart enough to get my code to do yaw rate and things like that (not even sure right now if the accelerometer that I have will even support that). So take what I do with a grain of salt because it isn't showing the whole picture, but I figured it would be awesome to collect some data and actually show people if any differences occur.

As of right now I have swapped out the front sway bar as that seems to be what everyone says the first suspension upgrade should be. I am a sheeple so that is what I have done.  I have autocrossed with the new sway bar, but due to my own stupidity I forgot the SD card to log data. So that will have to wait till I get a chance to find an empty parking lot or another autocross. The sway bar has definitely decreased the body roll of the car in cornering. At some point I will do some math for you guys to get roll bar spring rates of the stock and Eibach one. I will likely do some other math down the road to do with springs and what damping rate I want. But I gotta learn how to math again first.

One caveat with the springs is that the higher spring rate is likely too much for the stock dampers (not to mention the dampers have 120k miles on them). So when that upgrade happens, there will likely be a damper change too. So count it, that will be TWO things that change at once. Maybe I will put the springs on with the stock dampers for a run just for the hell of it, who knows. I am making it up as I go as always.

Alright enough blabber, time for me to brag about my girlfriend who I forced into driving for the first time at the last autocross. Her times were closer to mine than mine were to the next guy in my class...crap (for me that is). Her fastest run can be found here, look for the pretty and brand new Jag:

Zahra's First Autocross

Digital Dash Cluster

Hey all, time to unveil another cool project I have been working on in my spare time. I have been wanting to get an IQ3 dash for the car for a while. I have been told they even make one that just plugs into OBD-II so there is no real wiring required. The unfortunate thing about his dash is that it rather expensive starting at ~$650. Well I am cheap in areas that don't matter and have some skills of my own, so I decided to make my own customizable digital dashboard.

I kept flipping back and forth between using an Arduino and a Raspberry Pi for this project. Both have libraries for reading from an OBD-II serial connection. My gut was to go with the Arduino since I have more experience with the language and I know they are pretty versatile, but I ran into a big problem...displays. There was nothing that I found that seemed easy to implement and would allow for a touch screen without extra code. I also saw this as a good opportunity for me to use a Pi that I had gotten a while back and never used. I have pretty minimal experience with python but took on the challenge anyways.

The parts that I used for this are:

• Raspberry Pi
• 7" Touch Screen (Raspberry Pi Foundation)
• OBD-II to USB
• Blank Gauge Plate
• Custom 3D print Case (Will link to files for printing after testing)

The first thing to note is that the screen is a touch screen, which is really handy for being in the car. This means I can go in and change things or click on things without an attached keyboard or mouse.  The other great thing about it is that there is a sender board with the screen that turns the touch actions into a fake mouse essentially. This sender board then plugs into the Pi with USB and requires no extra programming or wiring! It truly is plug and play!

CRAPPY FLOW CHART

I used whatever the most current distribution of Raspian is for the OS on the Pi. I then set to work with making a python program that would pull the information from the car and send it to a GUI. I chose Tkinter as the GUI package to use (probably wouldn't use again for something more dynamic like this). The screen below is what I came up with for a general layout.

The boxes are changeable to pull the different data that is available over the OBD-II. I have also added color changing such as the coolant cell, where it looks at the temperature coming in and changes the background color of the cell depending on the values. So when the car is cold it is blue, normal operating temperature is gray, and if it goes over a set threshold it turns red. This allows for quick visual analysis of what is happening with the car. This same concept was put into the RPM value, where the number changes colors depending on the value to act as a shift light. COOL STUFF RIGHT! LETS SEE THAT IQ3 DO THAT!

I am still working on the programming, but at some point I intend to add a push button in place of the quit button that will trigger data logging. So you can push it when you want to start and it will save whatever data you have specified to a file and then stop when the car is turned off or if the button is pushed again.

One of the other hurdles that I am trying to get over right now is to set up the Pi so that when the car is turned on it will automatically start his program and make it full screen. I have read some things on the internet on how to do this, but the ones I have tried have not been successful. Any recommendations are welcome. 

Below is the case I designed to be 3D printed to hold it all. I will cut a hole out of the blank gauge plate and then bolt this whole assembly to it. I am still figuring out what I was to do about wiring in the power from the car to the screen/Pi. There will be more on that down the road.

Front of screen attached to 3D printed case

Back side of case and screen

I really hate when people post code for projects like this that are half finished, so at this time I am not going to post my code unless someone asks for it. I will make a second entry about this as I get it put into the car and work out the final bugs with everything. At that point I will release files for the 3D print and the finalized code that I am going to run. SO STAY TUNED!