Quote Originally Posted by jiho View Post
Then again, it can't be. Available info says the '93 Fleetwood ONLY had the 4L60 (700R4). So I have NO IDEA what BFYZ is about.
BFYZ is about what many calibrations are about in the GM database. The transmission type is undocumented. It's hard to say why this happened. Possibly the inclusion of automatic trans information s an option seemed superfluous in a car line that only offered automatic transmissions. It is clearly not a manual transmission. It clearly is a "no listing / all" calibration.

This I still don't get. These cars all have the same L05 with the same mechanical components. The only difference is the air cleaner box. How can the compression be different, let alone the power curves? The Fleetwood claims higher numbers at lower rpms:

Caprice/Roadmaster: 180 hp @ 4000 rpm, 300 lb-ft @ 2400 rpm
Fleetwood: 185 hp @ 3800 rpm, 305 lb-ft @ 2000 rpm

Normally I'd look for a different cam. Must be different exhaust?
Replacement GM Cam for Fleetwood and Caprice shows part no 10088155. Same cam as 305 TPI engines.
Cam specs here:
http://www.gmtips.com/3rd-degree/dox/tips/cams/cams.htm

The 9C1 cars got a larger cam but I'd look at the exhaust for the small difference in Caddy and Caprice.