04 Ralliart Sportback Turbo. Is it possible/worth it?

TheGreek · Apr 17, 2009, 08:20 AM

I have heard that a turbo car is often better with an A/T because it allows for a better launch and reduces turbo lag. If you remember, the Buick Regal Grand National only came with a four speed automatic trans. Many DSM's came with autos as well, and I know a lot of guys who swear by them. Plus, they didn't have the crankwalk problem that the 4g63's mated to a M/T did. Would that be true of the INVECS-II tranny in the sportback ralliart? I mean, would it be a good match? Can it handle the power? What would be the negatives? Doesn't the INVECS-II tranny respond well to manual shifting?

I haven't seen anyone with a turbo ralliart wagon, and I want to entertain the possibility.

If anyone here has done this, please speak up!

ridenrunwv · Apr 17, 2009, 03:25 PM

There used to be a guy on here with a turbo sportback. I remember because I have an automatic ralliart so I kept looking and reading on his. Probably going to turbo mine this summer when I get the cash if I end up keeping it.

GPTourer · Apr 18, 2009, 02:19 PM

Well, its like this, the Grand National was designed to be what it is, and that is a hi powered performance car. It comes stock with a turbo and a lot of power, so its not a good example to use if you want to justify turboing your Sportback. But it is possible to have an automatic built to hold more power. Level 10 has been doing it for a long time.

AznRico · Apr 19, 2009, 10:18 AM

very interested in reading up about this topic... AT with turbos, i know that the first auto turbo RRM sold to was a person here on the forums with a sportback. i couldn't find all the old threads though. looking to do this myself maybe by the end of the summer

hackish · Apr 20, 2009, 07:19 AM

Typically it is difficult and expensive to boost a 4 cyl with an auto. The big V8 guys have years of aftermarket parts and their transmissions are well researched. Want to push out 1000hp, a dozen companies make V8 transmissions. The slushboxes for 4 cyl are not usually strong enough to take a lot of power before the bands start slipping.

Aftermarket parts what? Most often they're also controlled by the ECU so just adjusting the duty cycle of the shift solenoid is a big thing. I've toasted a lot of AT's. Probably a dozen supras, a couple of hondas and a few oddballs. They're just not up to the task.

TheGreek · Apr 21, 2009, 06:27 AM

Thanks for the responses everyone, but I'm still not getting closer to an answer. Does anyone know for sure how well a turbo works in this particular vehicle with the mivec 4g69 and the INVECS-II transmission? Specifically, what is the most amount of power the transmission can handle safely? What is the most amount of power put to this transmission from the factory? Did they mate it to an engine producing more power in the Outlander? How about the Grandis, Galant, Eclipse et al. ?

GPTourer · Apr 21, 2009, 07:27 AM

No, all the cars you mention use the same engine in about the same form and about the same torque. If you go and get a basic turbo kit with about 5-7psi, you are probably not going to exceed the transmissions torque handling capability if you use it as a daily driver. IF you plan to take it to the drag strip regularly, most likely you're going to need to rebuild the trans stronger sooner rather then later.