dual GM TBIs [Fwd: CFM numbers]

[Greg Hermann]

>> Dear Sir:
>>
>> I am wondering if you know, or can point me toward a source for, cfm
>> ratings for GM tbi units.  I haven't been able to find them anywhere.
>> Thank you.
>>
>> Shannen Durphey
>> shannen at mcn.netShannen,
>
>        My apologies for the delay. The GM tbi units are not rated by cfm
>numbers but by displacement size of engines. 4.3, 5.0, 5.7, and 7.4 etc.
>        Although the 4.3 to 5.7 is approx 465-500cfm and the 7.4 is
>approx. 550-670 cfm.
>
>                                REP. Troy Brown
>                                Howell Engine Developments Inc.
>                                6201 Industrial Way
>                                Marine City, MI 48039
>                                (810)765-5100

Hey neat--now--are these (approximate) ratings based on 3 in Hg, (pressure
drop) like all two barrel carbs are, or on 1.5 in Hg like four barrels
are??? I believe that Holley, for one, rates their two and four barrel
Pro-Jection units on the two different standards. (All you gotta do is
multiply one by .707 to get the other.) Just wonderin' and askin'!

Regards, Greg