Re: Converter Suggestion - Big Al!!

CobraJet wrote:
> In article <218vi.130$Oo.104@[EMAIL PROTECTED]
>, Whole Lotta
> Tom <Whathu@[EMAIL PROTECTED]
> wrote:
>
>> Big Al wrote:
>>>>> Have a 950 HP on my 10 second OT street car. They are rated at a
>>>>> different vacuum level than regular carbs. Look into it before you
>>>>> go shopping. Was surprised to find out about this AFTER I bought
>>>>> mine:( Think they are rated like the two barrels.
>>>>
>>>>    Hmm. Where is this info on the Web? This is a new one on me.
>>>>
>>>
>>> Google is your friend:) Stolen from
>>>
>>
http://www.carreview.com/cat/parts/carburetors/holley/PRD_2173_2889crx.aspx
>>>
>>> Summary:
>>> Holley may be misrepresenting their HP carb sizes, a HP 950 is
>>> closer
>>> to a 830, a HP1000 is about a 870 if measured the same vac as a 47--
>>> series. The industry standard for cfm ratings was 1.5"Hg vac for a 4
>>> barrel. holley decided to follow the deciptive lead of it's
>>> competitors and use 28"wc which is 2.06" hg. Holly has all their
>>> carbs listed with flow spects. They make no distinction between a HP
>>> type and a older 4781 type. Unless you actually flow a carb, with
>>> holley's listings, you can't tell what flow it may be since the
>>> listed flows of the 4 barrels are not made with the same test
>>> standard. Their all listed together by flow ratings. I'm just for
>>> the truth in advertising, if holley actually told the test vac for
>>> carbs
>>> it would be better, Esp if they use different test spects for
>>> different 4 brl carbs. It looks like Holley uses a 1.5"HG vacuum
>>> standard for the 47_ _ series carbs and for the HP series they use
>>> 2.06"hg vacuum test standard. The result is a false comparison
>>> between the two carbs. I got tricked and many others will be also.
>>> Spread the word about this . The HP950 has a 1 3/4 base plate and a
>>> 1 3/8 venturi. A older 850 has a 1 3/4 base with a 1 9/16 venturi A
>>> HP830 has a 1 11/16 base and a 1 9/16 venturi
>>
>> I totally stole this stolen info and posted it at my place.
>>
>>
>
>    You be a thief, dude., thievin' this thieved info.
>
>    It appears that Holley still sells a 4781-C, and it is still rated
> at 850 cfm. So, the question morphs. Is the new 4781 identical to the
> old as far as airflow? Or is it choked down so it doesn't make the
> 950HP look bad?
>
>    And still, it is a cheaper carb that does not have the features of
> the HP. Shouldn't the "actual" 830 cfm flow of the 950 be sufficient
> to carry 600 horsepower?
>
>    Over 600 horsies, it appears that many 385 owners ****ft over to a
> Dominator flange Victor or similar. The current Dommies have likewise
> undergone many improvements in recent years.

Your 750 will work well while you sort things out.  Put off the carb
decision 'till later.  But, the diff between my 750 VS and my 850 VS on
the
460 is significant.  That's why I'm looking to move to the 4781
eventually.

As for the new 4781 and it's dimensions, the catalog shows all of the 47xx
DPs as rev C.  I'll assume the venturi bore and throttle plate dims are
the
same as always.

As for Dommies, never underestimate those who just want to go big.  The
750
Dom makes it even easier.  Still, with the strokers, roller cams and
inproved idle meterin, it's easier than ever to run a big Dommie.  You
interested in those?