RJDthecayenneguy

Interested in what you think the most beneficial performance modifications are on a 955 turbo, the options are endless. You should take into consideration the price, ease of install, and overall power and performance gains.

Excited to hear what people think!

Sniffer

Remap - got to be the hands down winner

wrinkledpants

I don't think any mods are all that worth it on the CTT. It's just too heavy to really reap any small power increases. It's not like a car where adding 50 HP makes a substantial difference to the power to weight ratio.

It's just like any other turbo car, though. Downpipes, tuning, intercoolers, W/M injection. You'll spend close to 7K when you're done, maybe get the power from 450 to 600 range, but the fun factor won't be all that different, IMO, since the suspension will be stock. At that price, you could have spent another 1-2K and found an old boxster to mod.

Best mod for any CTT is a set of etorqs, triple square set, hex bit set, and giant hammer. Keep the CTT properly running. That will be a financial task in itself.

knfeparty

I agree that modding any 955 CTT seems like an exercise in punishing yourself. It's a full-time job just keeping it running.

pastorom

What you're saying isn't wrong, but it assumes that every one has an extra garage space they can devote to a boxster. Some of us like the utility of a cayenne, and still want to make it as fun to drive as possible.

I looked at getting a tune too, and came to more or less the same conclusion, that an extra 50 hp wasn't going to make an appreciable difference.

My single biggest wish list item is something to improve the throttle lag and acceleration. Merging into traffic is scary sometimes because my cayenne turbo (2004) just takes so long to respond. 60 - 130 is great, and it just pulls, but it's initial acceleration from 60 that i'd love to improve.

wrinkledpants

That's not throttle lag. It's the transmission refusing to downshift. If the load on the vehicle increases without putting in a load-increase request (road pitches up, but foot stays in same position on the throttle), it'll downshift just fine like it should. But, if I put in the load request without the pitch of the road changing (pressing further into the throttle), it waits way too damn long to downshift, and then when it does, the acceleration is violent and I end up having to slow down.

The CTT has a lot of turbo lag, just like any other turbo car, but the transmission tuning is horrible. It shouldn't be in 3rd gear if I'm doing 15 mph, and it should be downshifting much sooner. If I'm asking for more load, and it can't comply with the current gear, then it needs downshift rather than hold the gear.

RJDthecayenneguy

I agree with what people have been saying about the difficulty in just maintaining a 955 CTT, and that the transmission can be questionable at times...How much realistically do you think the acceleration/0-60 could be improved with some simple things such as a tune, upgraded plenum, and bypass pipes?

wrinkledpants

Plenum and bypass pipes won't net you any power. Downpipes (bolted to the turbos) will net you about 20-30 HP at the crank.

A turbo S with 520 HP is about .2 - .3 seconds faster 0-60, but not much faster in the quarter (looking at magazine tests).

For comparison sake, the power/weight ratio difference between a full and empty tank of gas is like adding 16 HP. Not sure about you, but I certainly don't hit the loud pedal and think "oh man this is so much faster on an empty tank." In fact, I don't notice the difference at all.

So, see a part that advertises a 16 HP increase in power might seem like a lot, but the reality is the CTT is just too heavy to really feel that increase in power.

PupC

Use the manual shift mode on the shifter or the flip shifters on the wheel... Lots more fun to drive and shifts well too!

I have a blast that way.... and it don't cost "nuthin"

Oh and I also have a 2000 Boxster S to play with... Fun , but hands down would rather drive the CTT! Easy choice.

I also notice in the CTT, that a smooth accelleration from any speed is more beneficial than trying to push the gas pedal thru the fllor mat... Especially if manually shifting...

Of course if starting from 0, hold brake, raise rpm to ~2000-2100 rpm, then hit the gas hard... and hang on!

CTTS520

mtnrat

On an 05 CTT I did the cat bypass and a tune. Really not much real world difference. Om my 06 CTTS it seems a little faster, but really not that discernible. I think the best performance mod is having a place to keep your foot into it for longer.

PupC

I fogot to mention that I have the Cat Bypass, Tubi Exhaust and EVOMS Diverter valves... All of which were on the CTT when I bought it...

The Tubi does sound very nice...

PupC

I fogot to mention that I have the Cat Bypass, Tubi Exhaust and EVOMS Diverter valves... All of which were on the CTT when I bought it...

The Tubi does sound very nice...

Brit6

I have fabspeed catbypass, EVO intakes, and intake plenum.

It sounds a lot nicer with those 3 add-ons, you can really hear the turbos spooling and the stock diverter valve.

I also just replaced both of primary cats and pre-cat O2 sensors, the engine and tranny feel a lot smoother.

GrandeOak

^^my biggest gripe with my 2005 CTT.

Turning PSM helps a little. Sport mode in the 957 makes them way more fun in everyday driving.