DSG Gear Drive timing set update...

[More Power]

As of last week, 158,000 miles and counting. The gear drive is one of a few 6.2/6.5 aftermarket parts that I wouldn't build an engine without. Smoother engine running, accurate timing, and virtually no injection timing change throughout the life of the engine are the most important advantages.

MP

[gerry1]

Only have 12K on mine. Added it during a complete rebuild. Just seemed to make sense for the longevity of motor. Have not noticed any drawbacks. I have checked the timing several times and its still holding tight.

Gerry

[BUZZ]

The only draw back I can think of to gear drive, well 2 cons, noise and the horse power to run.

How loud are the gears?

I have 149,000 and will be changing the timing set in a month or so.
Thanks
Buzz

[Barry Nave]

Just over 60K. No noise, only time you can tell is oil fill cap open while running.
HP loss? HP gain while timing stays dead on and is eazer on the pump. Gear drives have always been used for power gains.

[gmctd]

Drawback?

Con?

Gearset noise?

Try the noise from the chain-set, oem OR fresh, oil filler tube open, engine running.

Does the picture of a chainsaw on an iron pipe come to mind?

Then, compare that horrendous sound with the clean, whirring sound of your new gear-set.

Yes, there is one drawback - when you drawback to pitch that chainset in the trash.

And, there is one con - when you con-gratulate yourself on selecting the gear-set over the chain-set.

Try it - you'll like it..........

BTW - you'll have to remove the oil filler cap, and listen real close to even hear the gear-set.

[Billman]

Buzz

A question was asked a while back about the power required to run the gearset.

Do you know?

[duluthsvo]

I have about 3500 miles on my fresh rebuild and I would have to strongly agree. No audible noise, much smoother and crisper engine, and I'd bet the benefit of accurate timing far out ways the HP to drive. DuluthSVO

[rjschoolcraft]

The actual question was, "What is the power to drive the cam shaft?" This is the same no matter what.

Gear meshes are more than 99.5% mechanically efficient, so there is probably more loss with a chain than with a gear set.

The reason that I asked about cam drive power is that I want to do gear analysis on the meshes of the teeth in the DSG set. I make my living designing and analyzing gears.

[eracers999]

The price of the gear set bothered me at first but i must say it was money well spent. After i seen how loose the timing chain was that came out of a 80k engine, the decision was easy.

Kent

[Billman]

I stand corrected, RJ.

'What power is required to drive the camshaft' makes more sense.

On Edit: How would a belt do compared to the Gearset?

[Marty Lau]

Originally posted by BUZZ:
The only draw back I can think of to gear drive, well 2 cons, noise and the horse power to run.

How loud are the gears?

I have 149,000 and will be changing the timing set in a month or so.
Thanks
Buzz Buz I chainged the timing gears and chain at about 165,000 miles I didn't go with the gear set primary because of the extra ~$200 I figured my truck ran real well up to that point with the cahin and I figured I was at about half life and having already laid out 2 thousand bucks for maintance and upgrades I saved the $200. I would tho not build up a engine without it tho expecting a long life. Just the way I made my decision.

[More Power]

Peninsular Diesel began offering the DSG gear drive in their engine lineup a couple of years ago. They resisted for a good long time, but now see the advantages. All of you coming to SLC this September will be able to see some truly incredible 6.5 engines they'll be bringing with them. It'll be worth the trip just for what they'll have for show-n-tell. :cool:

MP

[rjschoolcraft]

Originally posted by Billman:
On Edit: How would a belt do compared to the Gearset? A belt does not have as high of an efficiency level as the gear set... although it would be very quiet with nearly no torsional vibrations induced into the crank or cam. Longevity would be a concern. Robinson and Schweitzer have both built helicopters with main rotor drive power delivered through belts... usually quintuply redundant.

The gearset will definitely induce high frequency torsional vibrations into both shafts. This is the result of transmission error from both machining and tooth deflections. This has been my only concern all along with the gearset, but so much positive feedback from this forum has reduced that concern. I will be building my new engine with the gear set.

I would still like to analyze them, though.

[damork]

I've got about 40k on my truck since installing the gears. My opinion is there are no cons - this is what GM should have used in the first place.

Although I had about 160k on the truck when I installed the gears, it has run far better than it ever did with the chain setup, even when it was new.

[tom.mcinerney]

I ran a timing belt 140K miles on a VW diesel. When replaced it showed no sign of wear or stretch--i just lost my nerve.

Ron-
I imagine spiral/helical-ground gears would require a thrust bearing, for which there is no room. Do the spiral/helical ground gears also transmit torsional vibrations (possibly muted)?

[grape]

think of the tooth contact in a chain/belt set up compared to a gear drive. At most maybe 4 teeth are touching at the same time with a gear drive, the chain is touching over half of the big gear and almost half of the little gear.

Will DSG make me one with some form of adjustment so I can move the cam? I guess making offset keys would be my only option, it's just a pain.

[rjschoolcraft]

Tom,

Yes, helical gears also induce torsional vibrations. All things being equal, helical gears are quieter and have less transmission error than spurs. However, a precision designed and ground (AGMA class 13) set of spurs can be quieter than a sloppy set of helicals. It also depends on the tooth modifications and anticipated torque load.

A gearset designed for low load will be very noisy with high transmission error at high load (and may self destruct rapidly). On the other hand, a gearset designed for high load will be very noisy at low load.

Unless, of course, a patented process called differential crowning is used. These allegedly allow wide fluctuations in torque to be achieved with very low transmission error. I've reviewed the patents, but haven't come to a conclusion whether it's real or not.