G6, 3500, 3900

[RacerX11]

True. It is not as flexable as independant intake/exhaust timing, but advancing or retarding the entire cam still shifts the powerband up/down. This is why they sell timing kits to advance/retard the cam on pushrod engines. Retading the cam tends to help top end power, while advancing it helps low end torque. I wouldn't think they would be changing it more than +/- 5 degrees.

Marty

[v6h.o.]

I wouldn't think they would be changing it more than +/- 5 degrees.

Marty

some of GM's engines such as the new Northstar in the XLR and the 4200 inline 6cylinder engine can change cam phasing up to a total of 30degree's IIRC...

(been a while since i looked up the specs)

EDIT: the 4200 changes cam timing:

Exhaust Camshaft Position Actuator Description
The camshaft position actuator is bolted to the front of the exhaust camshaft and is integral with the sprocket. The actuator and sprocket can only be replaced as one unit. The actuator has a hydraulically actuated piston located in the hub. The piston has an internal helical spline that slides in mesh with the gear. As the piston moves, the piston and gear mechanism changes the timing of the exhaust camshaft, relative to the cam drive sprocket. When oil pressure is applied to one side of the piston, the cam moves clockwise and timing is advanced. When oil pressure is applied to the other side of the piston the cam moves counter-clockwise to retard timing. The total range of actuator rotation is 0 to 25 camshaft degrees. At idle, the exhaust camshaft position actuator is at full advance or 0 degrees

[RacerX11]

The DOHC engines can have more flexability, since they are seperate, and the timing as well as operlap is adjusted. If you advance or retard the cam too far on the single-cam pushrod engine, it will run very badly, since you are only adjusting the timing, not the overlap.

Marty

[RacerX11]

The DOHC engines can have more flexability, since they are seperate, and the timing as well as operlap is adjusted. If you advance or retard the cam too far on the single-cam pushrod engine, it will run very badly, since you are only adjusting the timing, not the overlap.

Marty

[GPXSS]

but this isnt a DOHC engine

"The variable valve timing system uses an electronically controlled hydraulic gear-driven camshaft phaser to alter the relationship of the camshaft as much as 40 degrees overall (25 degrees retard and 15 degrees advance) relative to the crankshaft."

[gpse3400]

He He DOHC YEAH!! Well you know me Chris, I personally love the 3900 for its.....Twin Dual Sea Shells on top of it........... Well it does look like sea shells!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Thats a really long belt! Looks like it belongs on a Ford Diesel! I wonder why they just didn't make it the typical way but just mount the tensioner in a different spot/angle..Oh well it's a nice package, compact, and quite possibly still light..... Not that its the best thing to do seeing all that fAAANNcy extra hardware is there but I wonder if it could be easily be converted to a simple 3400/3500 setup, yet still have the near 4.0L displacement. Ease of electrical hook-up and tunability.

[robby1870]

Yeah, that belt.....one tensioner and what 4 idler pulleys?!?! Geez. I read something like 90% of peak torque is available from 2000 to redline! Now, thats what I like about it....and its a pushrod:P

[TheProfessor]

i want to see that motor in a malibu maxx sometime in the future

[dbtk2]

I'm just wondering how similar the bottom end is. Is the block similar enough that we could stuff one of those crankshafts into our blocks? The heads look similar, so they could probably be adapted to a 3100/3400 and work quite well, assuming they flow better. Someone needs to buy one of these things and tear it apart to see exactly what we can use off of it, if anything, and how easy it would be to swap it.

Looks like a badass engine though. The UIM is huge.

Shawn

[SappySE107]

The bottom end wont swap into ours. Would be easier to use that block and see if our top ends would bolt onto it instead (whatever purpose that might serve).

[Maetrix66]

What I know.....

The 3900 is similar in the bottom end to the new 3500. The crankshaft is FORGED, the mains are different diameter than the older 60 degrees, and they moved the x24 crank sensor from the front pulley to the traditional crank sensor location, and did away with the traditional crank sensor.

Also, the new magnet array that goes on the center of the crankshaft is PRESSED on.

What I hope.....

so, in theory, one could procure a new 3500 engine, press off the reluctor ring, and press on a ring made to convert it over to the old style crank sensor.

I am sure that the variable intake plenum on the 3900 is ECM controlled, so I think the best swap will be to take a 3500, swap in a 3900 bottom end into the 3500 block (that variable cam thing has to have a weird mounting surface) and use the 3500 intake, with possibly the 3900 heads (who knows). Then swap this all into an older car, and use the factory ecm for a 3.1, tuned for the combination!!

Sorry GM, I'm not giving up my OBD1 yet!!!!!

[bszopi]

Won't work...

http://www.60degreev6.com/forum/viewtopic.php?t=4&highlight=3500+crank