Fair enough, and can't say I'm surprised. Any idea of the cost delta?
I suppose a lot of it depends on what you consider "engine". If one were to consider just the long block and not the ancillary sensors, emissions equipment, fuel pumps, etc. to make the engine run-- is it even close?
I could see costs running away if one were to include all the extras on the engine, whilst the transmission is largely a self contained unit.
I used to work in manufacturing at Ford, and I have a friend who was an IE (industrial engineer) there as well.
I'd say I have a fairly good understanding of what goes into making major items in cars, but I'm not able to give you a specific cost delta because that would depend on many assumptions too broad for this thread. I can, however make some general statements as to why engines would cost more ....
Engines have more components. While it's true that transmissions have gained some gears over the years (2, then 3, then 4, then 6 and now up to 10), that's not a lot of components relative to an engine. Engines have gained valve count (2 per cyl, then 3 and 4), but also have gained a slew of other things (going from OHV to OHC makes for more chains, gears, etc). VVT in all its forms from various OEMs also adds a ton of complexity with control valves, sensors, etc. Many engines are alum blocks with steel sleeves vs. the old days of cast iron blocks with no liners (though tech is changing that as cylinder hardening is advancing). Engines have more intricate castings; the engine block casting is far more involved than a transmission casing. Some engines now are even getting variable drive oil pumps; much more complex than the old standard PD pump.
Every single component in an engine or transmission gets design time, testing time, production time, etc. There are more components in an engine than a transmission (as a generality) and so the cost to produce that engine is going to be higher from beginning to end.
Further, whereas transmissions don't have to be "certified" to some standard, engines do. We all look at HP and Torque values when reviewing engines; those values come from very specific and controlled testing. Transmissions don't get that kind of validation. I'm not saying that trannys are not tested during design phase; they certainly are. But they don't get the barrage of tests the way engines do. Transmissions don't have to deal with the ever increasing changes due to emissions requirements and fuel efficiency requirements. All the SAE and EPA testing done to an engine drives the costs up; transmissions don't get "certified" to the level which engines do.
Engines just take more time/money to design, test, build and certify than do transmissions; that's a generality. There will always be exceptions, but the rule stands firm.
