variable intake...

[loki]

is there any engine other than the 3.9 with the active intake?

is there any proof or good rumors it's going to make it into more engines?

side question... would that not do much if anything to inline engines power band?

Edited July 29, 2006 by loki

[PurdueGuy]

what is "active intake"?

[loki]

what is "active intake"?

172463[/snapback]

the tech that gives the 3.9 that 2 hump in torque curve

it switches from a 2 "tiered" intake for low end torque, and one for high end hp....

can't think of a better way to explain it, other than it's electronicly controlled or it would be a passive intake (nothing moves), like anything you can buy .

can prolly look it up, but i'll see if anyone else cares to explain it, or just see who replys untill tomorrow

[loki]

http://www.media.gm.com/us/powertrain/en/p...20%28LZ9%29.pdf

oh, it's refered to as a variable intake manifold

[loki]

sweet, this died about 18 hours after i posted it!!!!!!

[razoredge]

Sorry Loki, I just dont know much about it. Thanks for the link it was an interesting read and helps me understand more. This is how Pontiac describes it in the G6 promo booklet.

New for 2006 is a 240-hp 3.9L V6 with sequential fuel injection, standard and only available in the G6 GTP. Proving the adage "theres no replacement for displacement" its speciality is a wide power band, thanks to an advanced variable intake system. Around town, incoming air is routed through a tract tuned for maximum economy and responsiveness. Put your foot down, and a second, larger intake tract opens, while the intake valve timing is changed to an aggressive high-performance profile for a habit forming surge of acceleration. This two for one lets the 3.9L provide 85% of its 240 lb-ft of torque from 1600 rpm to 6000 rpm, and kick to accelerate from 0-60 in 6.6 seconds.

It does seem to work quite well and we are averageing 24.7 mpg with our hilly country driving. Which also includes occasional "put her down" attitude. Fill ups off interstate and back on interstate showed a maintained 29.7 mpg on the DIC but we have not gone a full tank on any interstate to see if this kind of average could be maintained.

So with that said the 3.9 in the GTP is getting slightly better mileage than the SC3800 in our LSS. Our LSS on long trips maintained 26-27 MPG interstate driveing but is around 23-24 here in the hill counrty.

As for how the power comes on I still like the SC 3800, its just more solid through out the powerband but that is most likely the extra 40 lb.ft. and typical torque grunt expected from the 38, combine that with the superchargers continous increasing feeding capacitys and the 4 speeds long legs (50mph in first), the old L67 is just a treat to drive.

The 3.9 pulls hard once above 3000 in proper gear and is equally as fast or faster than the L67, it just doesnt feel the same in conventional driveing when you just need a little bit more. The 3.9 combined with the 6 speed makes you work a little more to get it in its sweet spot. The SC3800 is always in its sweet spot.

That said I surely hope if GM is going to keep this 3.9 around they quickly do neccessary internal engine work and engine systems maping to apply the Eaton M90 to the 3.9......................what a beast that will be while still maintaining respectable mileage for the power output.

As for the variable intake system being applied to other engines, who knows ? Seems to work well for the 3.9 but the 3.9 is still behind the competitions recent DOHC engines, though it does its performance on 87 octane.