Found 454/502 truck prom

[Clive Apps Techno-Logicals 416 510 0020]

> 
> This is from  page 16 of the 1999 catqlog.
> 
> "The conversion kit parts are intended for 91-93 Chevy GMC 10,20,30 series 
> trucks originally equiped with a 454 TBI engine and 4L80E auto transmission"
> 
> I don't know what ECM is stock for a 91-93 truck.  The 12366556 PROM may be a 
> performance parts only PN, don't have a broadcast code.  It must also be used 
> with a 18LB fuel reg kit# 17113186.
> 
> Page 14 shows the engine availible by it self 12371054.  It states " The 
> HT502 is intended for 1970 and eariler Chev and GMC 20, 30 series trucks.  
> The HT502 is not intended for use with electronic fuel injection.  When used 
> with EFI, under certain heavy load and high altitude conditions, engine 
> damage may occur due to lean fuel mixture condition."
> 
> I would tend to think the above is not recommended for a unmodified EFI 
> system.  ( since it's MAP/speed/density the ECM would never see the larger 
> engine properly.)


I would think that putting 20% larger injectors and a cam similar to the stock
one would get you in the ballpark using the stock ECU cals

Clive