Quote:
Originally Posted by alexiskai
Good clarification – I phrased it that way because, when Tod's design was launched, there was some grumbling on the HAMB that he had modified the "true" Winfield crowfoot chamber.
One thing I think is really important to note here is how quickly even a HC engine starts to starve for air. So look at these two dynos:
HC head, no other changes
HC head and dual carbs
You can see that by 1700 RPM, that's 40 mph, the torque curve on the engine with the stock carb is already starting to drop, and by 2000 rpm it's down significantly. This manifests as a slowing acceleration as you climb from 40 to 50 mph. Whereas the engine with modified carbs stays in the power band right through 2000 rpm.
If you're taking rides in modified cars, and you're impressed by their performance above 40 mph, that's the carb/manifold talking, in my opinion. |
Makes sense to me. If you think about the carb cfm vs. the CI of the motor, it's certainly seems like it's under carbureted. I'd like to see some dyno charts of the following:
1) Head only with original updraft
2) Head with dual Model B (or better than stock) updrafts
3) Head with single downdraft like a Stromberg 97
4) Head with dual downdrafts like Stromberg 81's
5) Head with triple downdrafts like Stromberg 81's
6) All of the above with a hotter cam added to the mix