Holden V8 253 and 308 engines with carburettors

Our Hot Rod Cams will give your Aussie GMH engine that bompity, rump, tough sounding idle that will have everyone looking at your ride when you idle into the next cruise night car park. Yet the lobe profile is not too radical to give you grief because of it’s modest lift and duration figures.

However both Stage 1 & Stage 2 cams start producing torque at 1500rpm and produce exciting torque around the 2500 - 3300rpm depending on your other engine mods.

Stage 1 cam’s torque band is strongest from 1500rpm to 4200rpm and can be used with stock stall converters for automatic transmissions.

Stage 2 cam’s torque band is strongest from 1800rpm to 4800rpm, and we recommend using 1800-2200rpm stall converter in most cases, and higher compression and free flowing headers and exhaust.

Both cams work well with a manual transmission and have reasonable vacuum to operate your power brakes.

Those of you with VN EFI engines will need to modify their engine’s computer for the fuel injection’s programmed fuel delivery because the OEM settings will just not cut it. The other alternative is to run the VN heads and a different manifold to run a carbie.

Final drive diff ratios
As a rule of thumb if you are running 3.08:1 diff gears and an auto with a standard converter then go for a Stage 1 Hot Rod Cam. If you are going to run an 1800rpm hi-stall converter with the 3.08 gears you could step up to the Stage 2 cam for an even loppier idle however in the mid range power it my feel a little sluggish with such a tall diff ratio if you are not in the right gear when accelerating. So remember tall diff gears in the 3:1 to 3.25:1 range will feel better under your right foot with the Stage 1 Hot Rod Cam.

Stage 2 cams work real well with final drive ratios of 3.5:1 and 3.7:1 gearing and with these gears you could even get away with a stock stall torque converter if you are a good engine tuner to dial in your carby and spark timing. However an 1800-2200rpm stall converter is more forgiving to novice engine tuners and makes the car more docile at lower speeds, however stamp on the throttle and it will really light up your day.

Going any higher with a stall converter in a regular driver is a bit pointless with a stage two cam, or going lower to a 4.11:1 gears, because you will be not be operating it in its optimum rpm range, so if this is the set up you want to run then you will need one of our Street and Strip cams instead.