How much did I miss out by not going with 6MT?
 

So I initially bought my 7AT Z Touring thinking of keeping it completely stock and driving it for daily commutes in the heavily congested LA traffic. However, lately I've been getting all these crazy ideas of putting bigger breaks, forced induction, bolt-ons, etc.

Now I'm wondering if all this mod is worth doing on an automatic transmission vehicle. My main focus is on supercharging the vehicle but how much power will I gain as opposed to supercharing a manual vehicle?

If you plan on going FI, the main issue will be the reliability of the auto trans, not so much the power. You can do a valve body upgrade, but you lose a lot of driveability from the ones I have seen on 350Zs/G35s.

The power gain won't be exactly the same. It will only be marginally different though. As DD said the power capacity of the auto trans is an unknown. On IS300s the auto trans was considerably stronger than the 5MT. Until we know the limits of both transmissions it's anyones guess really which one will be strongest in stock form. If you like the auto now, I can almost guarantee you will like it more with mods. I don't think its a waste.

The 7AT handles the FX45's 390 hp w/o a problem. I'm sure it's going to do much better than the former 5AT some had problems with in this area.

Lug.. exactly what I was thinking. I would not expect you would have many problems with the 7AT. It is a strong transmission and you will enjoy it.....

Yeah, it was the first thing I looked at. I have an 06 with a 5AT and that tranny limits almost anything you want to do performance wise to the car with the exception of light intake/exhaust mods. Almost everyone I've seen that did FI on the 5AT had to do major tranny mods to get it work.

just going to miss out on rev'n up and dumping the clutch, getting sideways and yellin YEEEEEEEEEEEEEEEEEE- HAAAAAAAAAAAAAW

Funny thing about that. Turn off VDC put in 1st with M mode and stomp it...see if you don't still yell YEEEEHAAAW...I do

After some brief research, I read turbochargers are superior to supechargers on automatic transmissions... if this is the case how much am I looking at to put a turbo on my Z? Will there be additional costs(parts) on the 7AT opposed to installing one on a 6MT?

Question: How much did I miss out by not going with 6MT versus the 7AT?

Answer: 1 speed.

;)

I don't know...I only have a few hundred miles on the car so far, but when I punch it, it puts me back in the seat...I'm sure it's the additional horsepower as compared to my 03 350z.

On the 350Z, the problem with either FI solution on an automatic is that the engine RPM spin up was too fast for the shifter. i.e. you hit the rev limiter before the tranny could finish a shift. The Auto also had problems handling the power of a lot of the TT systems. The new tranny should hold a lot more power (it holds 390 hp on the FX45 just fine stock) but we'll have to wait an see if the shifts are now fast enough. The shift point is also at a much higher RPM so that could help as well.

A turbo install is a lot more involved than a supercharger and as a result, generally a lot more expensive. The supercharger doesn't require any exhaust changes and is really just a simple bolt-on in front of the plenum with a piggy back on the ECU to modify the fuel delivery.