Nicks Garage 383 build

Just getting back to the SD455 Pontiac.....
P built this engine for racing. Completely re-designed block that was strengthened & had provision for dry sump oiling. It had round exh ports & the intake ports were widened at the pushrod pinch, & had steel tubes inserted, & the prods ran inside these.
As I said in post #194, the 1973 SD was tested by motoring journalist & DID run sub - 14 sec quarter mile. It failed emissions, & the RA4 cam was removed & a milder emissions friendly cam fitted, which reduced performance.

Agree with others that low dyno numbers are an enigma. Nick's recent 383 test shows that & he would not be the first one to come up short on HP..........
All the right parts used, nothing obviously wrong, but.....