Kevin in Atlanta

Did the 89 GT engine have a specific engine code within a range or did Porsche pull the engines with better numbers aside to be put in 89 GT cars?

My recollection is the latter.

Thanks

Rob Edwards

The serial numbers are different for GT motors vs. S4 motors-

89S4 5-speed motor is M28.41, 81K 00001 >05000,

89GT 5-speed motor is M28.47, 85K 00061>50000.

Kevin in Atlanta

Thanks for the clarification.

GregBBRD

The GT engines have different camshafts, so the designation differs.

Additionally, the heads are marked "GT", although PET makes no distinction.

928cs

Manual 1989 S4 (including CS): M28/41 81K 00061 and up (New cylinder heads from M28/41 81K 00121).
1989 GT: M28/47 85K 00061 and up.

My former 1989 CS had the M28/41 81K 00106 SP. It was replaced under warranty by the M28/47 85K AT 00106.

Kevin in Atlanta

Interesting. There's a ROW (Japan) engine on eBay with the GT stamping on an a non-manual car.

89 PORSCHE 928 S4/GT M28/42 5.0L 32V EURO SPEC COMPLETE ENGINE HAS 43,394 MILES