Transmission upgrade Question
 

I have a 2008 Boxster with an upgraded 3.8l engine from a 2005 997 and I was wondering if there would be any benefit from installing a 6 speed transmission for this engine. Is this possible and what would the benefit be?

depends on
- What transmission do you have now
- How are the ratios
- what you want to do with the car.
- what are the ratios of teh new tranny

You may get a higher top speed
You may get lower mileage at high way cruise
you may just get faster acceleration
It might be a transmission from another car, that's better suited (stronger) then the one you have attached to the uprated engine now.

I will have to find out which trans I have. I just bought the car and all I know so far is the engine and brakes upgrade. I am doing an oil change next week and will see what transmission I have. The care was Boxster base with a 5 speed tiptronic trans. I am assuming they kept the same transmission when they did the upgrade. I would like to have better MPG when I am just cruising but also have a higher top end speed and faster acceleration..... As of now It accelerates fast as hell, but the RPMs are in the mid 3's at highway speed and was justing thinking it would be nice to be able to drop those RPMs down when just cruising. You will have to excuse my ignorance as I am new to Porsche. I would assume that when I find out the trans type that I would know what the ratios are?

just leave it till you had the car for a while

Use the switches/paddles on the steering wheel
 

for a while and see how you like it.

The TIP is good in town and the switches can toggle you into a lower (or higher) gear when your butt feels it appropriate. Converting to a 6-speed is going to give you more shifts to the same speed. Many prefer the 5 speed.

As to speed, when you reach the TIPs top speed, you are already in trouble unless you have an abandoned runway or the salt flats to play on.

Converting the TIP to the 6 speed, you are changing suspension and axle parts so you better start with pretty much the back end of the drive train.