Thread: Runner Length
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Old 12-07-2009, 05:26 PM
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Quote:
Originally Posted by ERA Chas View Post
Sorry, I didn't make myself clear. I meant the chokes that Webers employ to go from 48mm IDA's to smaller like 44, 42 or 37mm for example. It's a tuning aid for them.

So I take it your computer adjusts the pulse and duty cycle of the injectors so as to not over carburate?

Using Webers, I always read that 52mm was too large for a displacement of 427 and 48mm or smaller was more beneficial.
Yeah, in a carb application, thoat size and intake charge speed are pretty critical. Too big and it won't idle or perform like it should at low rpm's. EFI changes all that. You can use really big throats to make power at top end, and still perform well in traffic.

But, since these are individual runners, you have to be very carefull about intake port and valve size. I used a set of Brodix heads with huge ports and valves. On a 4 barrel carb it would have made gobs of power. But I lost all low end torque.
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