dano, I don't think that for a tbi it would matter what firing order the engine uses. TBI's are essentially just electronic carburetors, they inject fuel at the same place a carburetor would be.
The clifford kit, is port injection and includes a bucnh of stuff such as new intake, damper, I think even a camshaft plus all the required efi hardware.
I'm under the impression that really late model 250's had a 2 barrel tbi efi system. Is your engine an earlier or later model (does it have the intigral head)
you may also try changing your intake for a four barrel type and getting a TBI system from a V8, I figure it should probably work..
Or if you like a challenge, make your own setup with efi components from other vehicles and using a Megasquirt controller.
In my opinion, if you want efi, no hassles and you've got cash, get the clifford system. If you don't have cash and are don't want much of a challenge try finding one of the late model tbi setups, or try changing the intake and use a V8 system.
If you really like a challenge, get megasquirt, replace the intake with three individual throttle bodies from a cavalier or something (one per port) and put in fuel injectors right at the port so you have a full port injection system (with individual throttles!!!)
If you have a VERY large budget, go to brasil and get a "new" 250 from a '95 chevy omega (they have EFI, port injection, even distributorless ignition!)
Luis
