I am new here, but have been browsing some topics similar to this, and have a slightly different setup and would like an opinion
I currently own a 1993 corolla with a 4afe. I like my car, the interior is spotless, the underside is spotless for being a NY car, and the only rust on the body is a tiny bit of rot on the drivers rear wheel arch and rocker. It is containable and paintable.
The only thing that I dislike about the car is the lack of power. Yes, I understand it is a corolla lol. When running right, it can pick up decently at higher rpm, but is just a dog after about 45 mph. I would like to boost it, run 5-6 psi from a t25 ebay kit, plan to blow the turbo in 6 months to a year, I dont mind that. but here is the kicker....
It is a A131L automatic. 3 speeds, no overdrive. The main reason the car is such a dog is because there is not enough "power band" available for realistic driving. Sure, if I manually shift it at redline it kinda helps, but thats just hell on my torque converter.
Can this transmission handle 150-200 hp? I would like to get at least 150 out of my engine, if not closer to the 175-200 hp mark. I feel like this will allow for a huge improvement because of the super long gears and having constant boost during acceleration. Does anyone have experience running a turbo with the 3-speed auto?
BTW: The engine currently has 125k on it, everything all original.
Side Note: I hear a "pulsing" at high rpm and cannot for the life of me figure out what is causing it, any ideas? Any help would be great. Thanks!!
With enough auxilary cooling to the transaxle fluid and differential - 200HP will likely be the limit on this car. Same goes to the 4-speed A245E variant - they were never really designed for that sort of power level.
Make sure the differential oil is changed on a regular basis - as this is a 3-speed, you have two separate fill and drain points on the transaxle - main transaxle and the differential.
You are correct, that that big spacing between gears will be an issue. For a turbocharged project - this could work against you. Even with a smaller ball bearing turbo - you'll risk falling off of boost and have to crawl back up there to make power. Of course, once you're at speed - boost will be not an issue, but now you are looking to bleed off the boost to prevent engine damage. Supercharger or nitrous are also other options for power adders for this engine - though less affected by the gear spacing, they add their own little quirks.
Engine swap is another option - you could swap in a 7AFE engine - would be almost a drop in fit. 1.8L vs your 1.6L - doesn't sound like much, but that added displacement will give you a nice bump in torque + not burn up the transaxle. You could also drop in a 4AGE or 4AGZE as an option - be the most costly option, given how popular they are - but will have to find away to get around emissions issues.
Not sure what registration/emissions regulations you have in your area - but that could put a halt on any mods you want to do to the engine. Doesn't prevent you from doing other mods - like brake, tire/wheel, suspension, and weight reduction efforts. You can do quite a bit to the Corolla, suspension and weight wise - make the most of the power you have, This is sometimes the most cost effective performance mod - most bang for the buck. Plus you don't screw up the most reliable part of the car - the engine.
