gear drive?

[70elko]

what are the benefits of a geardrive install om a 350 sbc

[MagicRat]

Uh...... it has no practical benefit.

Theoretically a gear drive provides more accurate ignition and valve timing, especially if the valve spring pressures are very high and the camshaft has exceptionally great lift and duration.

However, a really good quality chain and sprocket set is also very accurate, so any true advantage would only show up at the drag strip and might produce at most a tiny fraction of a second decrease in ET. But it would make no practical difference on the street.

However, SBC gear drives are very noisy. Have you ever heard one? It's like having a 50 ft mosquito under the hood. And it's not even a pleasing noise like a loud exhaust. It's an irritating, whining/shrieking noise. It's loud enough that you can forget about enjoying your car stereo. You will have difficulty hearing anything else from the engine, so diagnosing other problems (ie knock or ping) becomes very difficult.

The drives use straight-cut gears (because quieter, helical cut gears would place too much thrust on the idler gears and the camshaft) which produces the noise. There have been a few engine designs that use gear drives as original equipment, but those gears are nylon helical-cut gears which are much quieter, but much weaker than the SBC gear drives.

So IMHO the drives are far too noisy to be comfortable for driving on the street. But some guys like the noise, because it screams 'I have a real race-car engine!! to everyone around.

[72chevelleOhio]

I have a real race-car engine.















...no not really.

[bobss396]

For street usage (except for the awesome sound) there is no advantage.