Obviously the ecu/tcu is biggest upgrade and the most noticeable. Is there anything else worth doing that I would notice just from driving around or no? Talking easy stuff here that I would notice a difference driving that doesn't cost a fortune... Thx.

I did K&N drop in filters and deleted the mufflers on my CL65. Still waiting for my tune from EC. Simple cheap mods and while the filters are not noticeable the muffler delete made the car noticeably more responsive and loud enough to actually hear the exhaust while driving. Next upgrade that should make a noticeable difference on mine will be a Quaife LSD. Definitely not cheap and simple.

A smaller S/C pulley but then you'd need another ECU tune to the most out of it. Depending on who did the tune, they may reflash it for free.
What do you consider a "fortune". That word means different things to different people when it comes to their cars.

Also what motor you have will make a difference. Like lphillips said, you can add a smaller locked pulley to a supercharged 55. According to another member on here you can tighten the wastegate screws on the turbo cars but your sig doesn't say if you have a supercharged 55 or turbocharged 600 or 65.

I have a cl65

Well, I also added a Dennison Gateway 500s to allow music to stream from and hands free calling from my I phone 5. Also a Aeroforce interceptor gauge I mounted in a custom panel I made in place of the front ash tray. A line lock. Spare rear wheels & drag radials will come next spring. Just a few ideas.

Ha. Was talking for speed mainly. So I guess k&n filters would be the simplest next step.

Ha. Was talking for speed mainly tho the hands free system sounds like a good idea. So I guess k&n filters would be the simplest next step.

The Quaife LSD is a little more involved than the filters, but by far the best way to get the most out of the power your car is making with the tune. After that you can consider a trunk tank, supplemental heat exchange and catless downpipes. Most don't venture into the big boy turbo upgrades it all depends on your wallet. Getting an extra 60-100hp comes easy and affordable. After that its much more of a financial commitment, and shop time but it can be done.

On my CL65 i did heat exchanger, mezere pump, Trunk Tank, Cat delete, Intakes and ecu/tcu. The car runs hard. As for the intakes i custom made them myself. Cheap and easy. The car breathes much better, you hear turbos and blowoff valve. All the stuff i did is very inexpensive if you know where to find stuff. I did all those mods for under $1500!!! I will be trying to do turbos, intercoolers, valve body and LSD diff over the winter. Also going with a speed driven tune.

I'll probably stop where I'm at then. I really was looking for something quick and easy (like tcu/ecu) with a good bang for buck. I'm not going to the track so I probably won't notice any incremental increases from leisure driving and I don't want my car to spend too much shop time for minimal gains. The tcu/ecu was just so good that I'm spoiled now. Ha.

Any pics of your custom intake? The factory intake/filter system looks horribly restrictive. I have thought about building a "track intake" that would basically just come from the turbos straight out to the front of the car with just a screen rather than a filter.

Does anyone know anybody who has gone bigger turbos? Im sure thats the biggest gains and I want to tackle that over winter.

post some pic please

and what about the sensors ? what did you do with them

Down pipes and rear muffler delete with a retune.

Add. HE/pump
Trunk res
Exhaust
100 oct retune
Custom air intake

post pics of your custom CAIs!!!
I have seen pics of the one on therickers car