Improving A 2001 Le

Hello and Welcome to the forum.

The 8th gen Corolla takes pretty well (response very favorably) to suspension and brake upgrades. As for the engine, not a bunch you can do unless you dump a good portion of that money into the engine. Even then, the gains will be limited to the chassis and transaxle durability. IMO, not an effective investment, unless the car has some sentimental value to you. Also depends on your ultimate goals for the car - want something to go fast in a straight line (thing drag), something that can take corners (think Auto-X), or a little mix of both. This going to be a daily driver? Do you want to build it up right the first time or will you rather fix stuff that breaks as they happen (depending on how you answer this and your power goals, $10K may not even be enough)?

If I sat on $5K-$10K that I had to spend and this was my daily driver - I would take about $2K to $3K (max) to upgrade to forged, lightwight wheels, decent summer tires for 70% of the year and toss some winter tires on the OEM ones, adjustable sways, go with a quality springs and adjustable struts, chassis stiffeners (lower suspension braces, etc.), upgraded brake friction material, SS lines, appropriate fluids - best bang for the buck. Corollas with their naturally compliant ride, they will seem to take a quantum leap in handling improvements compared to other cars with the same amount of money dumped into them.

Engine I wouldn't touch, unless you plan on running an EMS system to take advantage of any "improvements" you make to the engine. That means a decent amount of dyno time and standalone tuning. Your typical bolt ons (intake, header, exhaust) make minimal gains at best, some of the better numbers I've seen out there are 5-7WHP gain (Celicas and MR2s tend to be a little higher because of different tuning, heads flow a bit better - even so, they peak around 10-12WHP gain). Doesn't mean that there are no performance options, just need to pick and choose the right combinations. Aggressive cams, good P&P work, bored throttle body, stepped header, engine stroking, increasing CR, etc. - lots of stuff you can do to the 1ZZ-FE going the naturally aspirated route. Then there are the forced induction option - turbocharger, supercharger, nitrous, twin-charged, engine swap (2ZZ-GE is an excellent choice)? Only time and money comes into play here.

But keep in mind that overall balance - doesn't help you if you turbocharge the 1ZZ-FE within an inch of its life (can push up to 300+ WHP with some significant internal upgrades) - if you can't stop (brakes are too small, not enough capacity), car overheats (need to address additional cooling), or blow the transaxle apart (automatics start to give out around the 200-250HP range without help, manuals with upgraded friction can take a bit more but now you are looking at axles and bearings being the weak link). Chassis limitation are also pretty close to the this power level. Older body on frame cars had some tricks to deal with crazy power levels - generally unitbodies do not, unless you do some welding and fabrication yourself (skip welding body seams, gusseting corners, even weld in a cage).

If you are OK with all the above, then by all means - go nuts. The plus or minus - not many people start off with a Corolla, so you will have a different platform to build off of. But a recent plus - more aftermarket components are available for the 1ZZ-FE, mainly to the efforts of the MR2 and Celica enthusiasts. 2ZZ-GE components and many forced induction kits are readily available, so you have more choices now than what was available several years ago.