Wow. Im back for alittle and hope that the s12 will make it through the year so that I can make it a full street race car. I have plans to run a t03/04 with high boost for the engine. Should make out for some sweet CA20ET power. But for all of you who want to do a CA20ET conversion, i have some words of advice and some words of caution whne attempting this....conversion more than a swap. Many of you have come a LONG way since we joined the forums and are learning more and more about these cars everyday. I would first like to start by congratulating everyone who has done swaps, conversions, upgrades, and just overall s12 maintnence. I see these cars as having ALOT of potential to beat out s13's because of weight and handling. Although most of us have had a hard time finding upgrades for these rare cars, we have made due with what we have and also created some custom things in the meantime. So here for you now is MY conversion from a notchback ca20e to the only notchback turbo ca20et in the US. P.s. Ill add pics later, but its pretty detailed for right now.
I started the project my summer before college and all through college's first year. I had the help of my best friend Tj, the guidance and trusting of my father, and blessed with almost all the tools and hand cleaner i could ever need. With all other upgrades aside, i will explain what is needed for the engine in each aspect. Some things might differ, but I will try to adress EVERYTHING needed.
Electrical:
This for many is the worst part about building cars. Its hard to understand if you dont have previous knowledge about electronics. I for one had my dad, an engineer, but still ended up figuring out most by myself. I started with (2) cars. A 1985 CA20E notchback with good paint, a shot suspension, only 122K origional babied miles on the engine, and a smokers interior all for $1000 US dollars. This was my first car, so it was reasonable and clean and ran good.. The other car was my parts car I picked up from South Carolina. It was $800 for a 1985 hatchback with a blown t25 turbo, shot suspension, and an engine that at the time was leaking oil from around the rings. It also had 189K miles on it. Upon building the ca20et once before in "Project Dumbass" I used the non-turbo wiring harness to try to fuel the car. Bad idea. For the CA20ET wiring project you are going to need these things.
1) CA18ET ECU
2) CA18ET EFI Wiring harness (ECU-->Injectors)
3) CA18ET Main wiring harness (CoilPacks-->Rest of car)
4) CA18ET Coil packs
5) CA18ET Distributor without the vacuum advance
6) CA18ET O2 sensor (Bosch actually works good)
Out of those 6 things, I had none of them. Because I started with a non-turbo car. If you were to get your hands on the shell of a ca18et car with the turbo wiring in the car, you would be set. For everyone, the notchbacks will not be turbo in the US or canada. So look for hatchbacks.
With anyone wanting to do a CA20ET into a hatchback, you will need to do the following depending on options in the car. You will have to strip the plugs for the taillights, you lose the light in the trunk, change out voice boxes in the rear of the car. Wire in the security box under the passanger seat, take off all the dash and re-wire everything . This was the WORST part of the swap. If you all remember the pics of behind my dashboard. Wire the wiring harness into the engine bay and all the way to the coil packs. Pretty B*tchy huh? I hear that the newer cars like 86+ have the ca18et coil packs that look like little blocks instead of the tootsie rolls. They also have the dizzy without vacuum advances, but i cant assure of this. So with everything wired up we can move onto the engine specs.
Engine:
This is the most important part. The stock CA20E engine sucks. Flat out sucks. It was built with "matchstick" rods, thinner and more flexible rings, and a weak bottom end. I purchased the complete engine kit from www,importperformancepart.net with the upgraded options of the TOGA main and rod bearings and the TOGA high flow oil pump. I think these options were a good addition to the car. Starting from the bottom up I will tell you what I used and why I chose that over other options.
1) CA18ET oil pan - yes, you need somewhere for the oil to return to, why not just use the stock ca18et one, its a direct swap. A no brainer.
2) CA18ET oil pressure sender - yes, you have to get oil TO the turbo somehow.
3) CA20E block - mine had only 124K miles on it and the walls of the cylinder were in perfect condition.
4) TOGA main bearings - all i have to say about these is that when they say 25% more flow, they mean it. I even did some testing with a micrometer and data sheets. They dont lie. I got a 24.67% increase flow amount when i calculated it, so they just round to 25%. These bearings are awsome, and for like $30 they arent a very costly upgrade.
5) CA20E crankshaft - again, it looked good and stayed with the ca20e block setup.
6) TOGA oil pump - another good pump that has some GOOD size oil sender holes. Another not so pricy upgrade. The only problem was getting the dipstick out of the old one and getting the crank sprocket off.
7) Pauter 1000hp forged 1off CA20E rods - cost me $742, but worth it in the end. Beefy as hell. The LAST part that will break in my engine will be that.
8.) Cast pistons with lower compression + new rings - they lowerd the compression a little to allow for higher boost. Im not talking ALOT of c/r, just a little, plus they were new!
9) Copper jacketed head gasket - copper is good b/c it squishes under pressure. Making a nice seal. This was nice.
10) CA20E head with CA20E cam and a small port job done - again, it looked better and had less ware then the ca18et head I had.
11) new timing tensioner and belt - duh
12) CA20E intake manifold - personal prefrence for the piping.
This is not that much, most of what I needed came in the engine kit from that website. It was all just a matter of putting it together. next is the air system.
Air System:
Well with all forced induction you need to pipe things different. I used a starion front mount intercooler with the thing modded to accept 2" endtanks instead of the 1.7/8" I also made 2" intercooler piping all the way from the turbo to the intake manifold. I ran a crushed DSM 1G blow off valve that was good to like 22 or so PSI. T25G turbocharger from a s13. Spools fast and boosts hard. 3500rpm in 5th gear will still pull you into your seat. I have one for sale for $250+shippin'. if they want it. Im going bigger and even better. I used the ca18et exhaust manifold. Used a t25 3" downpipe to a 2.5" exhaust with no cat and a duel tip.
As you can see, it took me a while to write this because skool :) has been taking over all my time. I will try to update this with anything I think of as we go. As for now, here is a start. Thanks.
Yellow (O=O/ S-12 \O=O)