Transmission power

what is the difference in drive quality of a regular v6,3.8L transmission and the same with 6-speed with overdrive? (the car without overdrive has HP=205@5200 engine while the one w/ overdrive has HP=197@500)

In the first sentence of your post, 3.8L should refer to the engine, not the transmission. I looked online at the 2010 T&C, and all the trim levels seem to have the same engine, which appears to produce 197 HP @ 5,200 RPM. I couldn’t find anything specific about the transmissions, other than that they are all 6-speed autos.

Could you specify a model year? The 2011s all feature a 3.6L engine with much higher horsepower. It appears that the 3.8 is an OHV (pushrod) engine and the newer 3.6 is an OHC engine, presumably with 4 valves per cylinder.

Either way, a 3.6 or 3.8 L V-6 with a 6-speed auto should scoot a minivan along well enough. My Odyssey has a 3.5L with a 4-speed auto and it gets around OK!

Remember, power comes from the ENGINE, not the transmission. The transmission just determines how effectively the engines power is used.

Thanks, my mistake about the transmission. Question is about the engine, I’m still learning!! Anyway, I’m trying to decide between an '07 T&C and an '08 T&C. The '07 does not have the overdrive while the '08 has the 6 speed w/ overdrive. Both have 2 valves/cylinder. I mainly do city driving but have been told that a lesser engine will not maneuver well on the hwy. True?

Your are absyessing over trivial stuff. Both vehicles have plenty of power. Drive both and get which one feels best to you. If you want to spend time, go over the maintenance history on both cars. This could mean digging around in the glove box to see the owner’s manual and any service receipts lurking in there.

The one with the most complete, up to date maintenance history is likely the one to buy. HP of the motor isn’t as big a deal as how well a car was maintained by the previous owner.

thanks!

How about gas mileage and engine wear? But your understanding of the numbers and terms is way off. You are asking about an engine, a v6 3.8L engine, and how much horsepower is available given that engine when the car is equipped with (I guess) a five speed transmission versus a car equipped with a six speed engine.
The engine’s horsepower is whatever that engine can produce on it’s own. The torque created by the engine and the transmission, at certain RPM’s, is a different matter. Which should be measured at equal RPM’s for comparison. But I do assume that you mean the car with a six speed put out 197 HP at 5000 RPM versus the five speed car’s output of 205 @ 5200 RPM.
The five speed car’s engine will probably make the car faster through the lower gears but will redline much faster at high speeds in the car’s top gear, and will use more gas and wear sooner. The six speed’s engine will redline at higher speeds, have better overall fuel economy, and will last longer. As far as drive quality? Define that. My idea of drive quality is not how fast a car will run a quarter mile, or if it will keep accelerating over a 110 mph.