Do the manual transmissions hold up well to a moderately modded engine or am I just asking for trouble by modding my engine? I'm not looking to do anything crazy, just the usual CAI, pulley reduction, exhaust,.....kinds of stuff.

 

Are you asking about mods on a Auto Tranny or Manual?

 

Basically increasing the HP leading to tearing up the transmission.

 

Your biggest issue is whether you want to do more preventive maintenance on your a/t if you mod. Mods increase the operating temperature (higher torque -> higher friction loads on the internal components of the a/t -> higher temperature for the transmission fluid -> quicker failure of the transmission fluid) for the transmission. The transmission fluid will need to be replaced sooner than it would in the absence of mods. A simple drain and re-fill is NOT a replacement; with a drain and refill, the old fluid in the torque converter and the transmission body remains to contaminate the new fluid. You would have to do ~3 drain and refills one right after the other (drain and refill, go drive the car for about a 1/2 hour, drain and refill, go drive the car for another 1/2 hour, and drain and refill one more time) to get close to about a 95% replacement.

Or, you can just mod away and drive the car until the transmission fails at about the 60K mile point.

Or, or, you can dodge the bullet and not mod and hope that the transmission lasts 100K miles.

Or, or, or, you can do what I am currently doing - researching a way to be able to replace the transmisison fluid in one session. My research efforts are still very preliminary, so, don't anyone go and get their hopes for a solution up.