924Board.org

[jwalin]

I was wondering what the general consensus is on the differences in the auto and manual engines in the NA 924. I believe there was a compression ratio difference but that was it. Any opinions? (not opinions about the transmission!)

thanks,
jeff

[JvGinPDX]

As I recall, it is the same engine. The flywheel would be different, the engine for the auto might not have a pilot bearing installed. The throttle and pollution equipment mightbe different as well. I would look in the Haynes book for the answer. I have read of people going from auto to manual, (when the auto dies. It should be possible to do the opposite too.

[Pat]

There was no difference between auto and manual transmission engines of the same year. The Automatic transmission was offered first in the 78 model year. The US market engines went from 95hp to 110hp in 77 1/2. They achieved this by raising the compression along with other modifications. If it's European or ROW the cars had 125 hp until the 924S. The US market got another raise in HP in 80 to 115hp by raising the compression again and adding digital ignition. So if the cars are the same year and same market they will have identical compression, but if you compare a US '77 manual to a US 80' automatic transmission they will have different compression ratios. If your talking about a 924S I've typed this for nothing as I'm only sure for the early 924's.