3900/F40 dimensions

[alpine67]

Okay, so I have searched the forum for physical dimensions of the above referenced engine/tranny combo straight from a G6 GT and have come up empty. Does anyone have the outside dimensions in length and width with all accessories hung on it and total weight of this package? I should also add that I don't have a G6 GT or engine/tranny package to measure otherwise I wouldn't need the help! Thanks in advance, and awesome forum!

[ericjon262]

I know the F40 is longer than typical 5 speed manual transmissions, how much, I'm not sure. FWIW, I know that combo fits in a fiero just fine

[alpine67]

Thanks! Could you point me in the direction of someone who has done the Fiero swap? My swap would be to put this combo in a Saturn coupe, using as much of the ECM/BCM controls and wiring from the G6 as possible so as to not run into the typical issues, but I don't know if there's room in the engine bay for it.

[alpine67]

So I spent some time in the local pick 'n pull today. There was an 08 Outlander with a 3.9 LZ9 in it so I made some crude measurements. Sadly someone had raided some parts off the engine or I would have grabbed the whole cradle, engine and tranny assembly (1/2 off this weekend) just to get the some of the parts other than the engine that might work - Edit - see below.

There was a Saturn sedan sitting next to the Outlander - what luck!! What I discovered is that the 3.9 engine itself is within an inch or two of the Saturn 4 cylinder engine. That leaves about 12 inches in the Saturn engine bay for a transaxle. Edit I also measured the distance between shock towers and surprisingly they are very close - track is also about the same. I have an F40 in the garage that I need to measure, but unless I'm off, it looks like the 3.9/F40 would occupy about the same space. What I'm not sure about is the radiator to firewall spacing - that looks pretty tight and the placement of the alternator doesn't help. Edit - F40 is ~13 inches from bellhousing face to end of case - may be very tight. I really need the total length from a G6 3.9/F40 to be sure.

Is there anyone that re-programs the 3.9 ecm yet? That seems to be one of the common themes I read about on here. I would like to eliminate the key theft and auto tranny stuff, as well as the fature that deactivates cylinders for fuel efficiency. I think everything else might be okay. Edit - nevermind! I see that Sinister does this.....

[caffeine]

HPTuners supports the 3900 PCM

[alpine67]

Thanks for all the suggestions! I went back to the pick 'n pull again for some other stuff and drooled over the 3.9 I spotted earlier. Sad to think it will be crushed in about a month.... I really need to find a wrecked 06 Pontiac G6 GT w F40 for all the stuff I need as it would make the swap much easier. Stay tuned!

[alpine67]

I'm still thinking about that 08 Outlander 3.9 at the pick 'n pull. So are there any differences between the 06 G6 GT 3.9 and the 08? Are the differences in the electronics? I haven't studied the electrical components as in the various sensors on these engines, so any idea of what would not be needed to run an 08 in 06 mode, with F40?

[Forgotten User]

before you get to far into this you might want to look into the flywheels for the F40. Someone on the N-body forums has a F40 swapped Alero and went through a hell of a time finding a replacement flywheel, apparently GM stopped making them and no aftermarket company makes them...

[alpine67]

Hmmmm, thanks for the info. I'm still in the investigative stage, but if there are other issues with the combo I sure want to know before committing to it!

[alpine67]

I'm still working on this!! I found a G6 3.9 flywheel and clutch via a Fiero guy, and yesterday scored a wrecked 06 Impala very, very cheaply. So what I'm looking for now is the G6 intermediate shaft (jackshaft). Anyone have one of these things collecting dust or know of a workaround for it? I've got a Cobalt SS jackshaft but that won't bolt up directly - will need an adapter to bolt to the 3.9 block - G6 unit would simplify this! I'll worry about axle shafts once I figure out the engine/transaxle mounting.