Stromberg BIG97 Cadillac 331 gains 40hp

BIG97 3x2Watching a BIG97 equipped Cadillac 331inch race engine (out of an Allard) on the dyno is not something you want to miss. So off we went to Connaught Racing Engines in Kent, UK, to watch and help with jetting and tuning. The way the driver wanted to go was with three BIG97 Primary carbs for this engine, on a direct linkage. The old Edelbrock intake was opened up to take the bigger throttle bores. And the final results? Not bad for an old Cad motor!!

405lb ft torque at 3500rpm and over 350hp at around 5500rpm where these old intakes max out. Best of all, the BIG97 added some 40hp over the regular 97s, even with that old style early intake manifold. We didn’t even have to change the Primary stock jetting (0.56inch main jets). And there were no issues with residual fuel pressure on shutdown, either.

Big thanks to Peter at Connaught Competition Engines for driving the dyno, and Gus Gingell who built the engine.