Clutch Replacement: what performance mods to do?
 

48k miles on the car...original clutch.
I've had a second RMS or IMS leak (first was covered under warranty....porsche is saying they're only going to pay 1/2 of parts and labor...I'm not pleased about that...seems they should cover it all since they didn't fix it right the first time...'there's an updated seal that will fit it'....ya right)

anyhow, if I have the transmission down, I'll likely update the clutch since it's probably only got another 10k miles in it)...so, what performance mods should I consider doing while they're in there?

I would take a look at your IMS bearing to determine if you have a single or double. If single, you can update to the newer style without taking the engine apart. If you've not read up on this, please refer to this:

http://www.lnengineering.com/ims.html

You might want to think about a limited slip differential.

Please post more about the LSD. How much are they? Where do you get one? How much is instaling expected to cost? Is it really noticeable for a car that is not tracked, but drivin hard for fun?

What about a lightened flywheel?

I did that on two priors cars I owned when they had clutch work - one was a mazda RX7, the other a miata.

on each car - it made the car much more responsive and quicker. you reduce the weight of the flywheel, requireing less inertia to spin it. i believe it's the same logic that makes an underdrive pulley make power - there is less drag on the mtoor - less power is drawn to spin the flywheel - so more of it gets to the ground. it doesn't "create" horespower, it just frees up some that is already there being wasted.

my cars felt quicker shifting, and also felt to run through the rpms faster. overall it made m y rx8 and miata feel noticeably more responsive and faster.

no idea if people would recommend it on the boxster - or how much it costs - but i would certainly look into it. i plan to when i do my clutch.

i have 75k on the original clutch!

talk with "insite" for recomendations on light flywheel. It is not simply bolt on and go. You currently have a dual flywheel and you want to switch to a single mass wheel. There are problems associated with that such as chatter and IIRC Mr. Raby commented on the harmonic imbalance of a single mass wheel leading to vibrations and ultimatly catastrophic engine failure.

There are several brands of LSD. Quaife is popular. I believe Cusco and Kaaz make them for Boxsters and some custom shops build them as well. They are around $1300-2000 if I recall correctly. They will help with traction accelerating out of corners and stability braking into corners. Frankly, in my opinion, I would not get one unless you are tracking fairly regularly. It is relatively expensive and helps in very specific scenarios and won't make a difference 99% of the time on street, so the cost/benefit doesn't add up for me for the street. Plus, if you NEED an LSD on the street, then you should probably be on the track.