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hi, im brian
I'm buying a s12 ca18et tomorrow and a uninstalled t25 turbo.
I have alot of questions.
Like where can I get a good cheap exhaust/intercooler?
what are some quick cheap upgrades?
what is the max boost with everything stock?
what limits the boost at this point?
what are some common problems with this motor/chassis
I'll be searching around this forum but i'd like to set this up so I have all this info in one place.
Pics will be posted soon.
Wow Brian, I can't believe no one answered. I have a CA18ET and like it a lot. I use mine as a daily driver, so I don't get wild with it. I found an intercooler on ebay for about $100, all the connecting pipes about another $100+. The boost on the stock setup is about 5-7 psi and there is a pop-off valve on the intake manifold. Most increases in boost will require that get replaced with a standard 1" plumbing pipe plug. I would not plan on asking much more out of this engine unless you are going to prepare it for more boost. Arro has written tons of material on here about this, "Cliff Notes" are to replace the head gasket (I used a Cometic metal gasket) and get ARP studs instead of head bolts. This way the engine can handle probably 12 psi before you really have to get more exotic fuel control stuff. I have the OEM injectors and I replaced the fuel pump with a Walbro 195 pump. I have no problem flowing enough fuel, actually a bit too much under boost. I added a wide band Air Fuel Ratio meter to keep tabs on all this. Look up Keith on here, he has lots of excellent pictures of his early mods when he still had this engine in his car, I used a lot of his ideas. As long as you don't intend to race this setup, the engine will be ok. If you want more, you need a more robust engine and suspension setup to accomplish all that. Hope all goes well with your car!
I didnt even see this I would of bedn the first to answdr lol wow anyway all good advice! Get some pics up when you can. T25 is a good upgrade if its the t25 from the sr...
I've been pleased with it, not sure of it's original source. I got it from a member in Canada years back. It originally had a curved extension to the compressor outlet, but I took that off.
There is a T25 (from the CA18DET usually) and then there is a T25G (usually from an earlier SR). Take a picture of the compressor side and post it and I'll tell you which you have. I have a T25G sitting on the shelf.
Basically, the T25 is just a tiny bit better than the T2 that came on your car from the factory. The T25G is more robust and you can probably get 15 to 17 PSI out of it with proper intercooling and fuel management.
The advice that cajun1guy gave you is all good advice. If when you're reading through my older posts you ask yourself why I say use a narrow band, it's because with this engine you don't need (or want!) to tune lower than stoich. 14.7:1 fuel mixture is all the narrow band can watch for, but on THIS engine you don't want to go tighter than that for fear of damage.
Also, no matter what anyone else tells you, DON'T go 3" on a T25. You will see some boost creep at WOT, and some boost spike at sudden acceleration. On more modern engines, the timing might get dialed back a bit by computer, but your CA18ET isn't that sophisticated. You don't want spike or creep, And you don't want fuel ratios below a safe 14.7:1.
2.5" exhaust, a medium-sized intercooler, and a narrow band meter to make sure it stays at 14.7:1.
Wide band to me us useless on a CA18ET that hasn't been properly built and can't handle leaner mixtures.