Re: Converter Suggestion - Big Al!!

In article <cNavi.1571$3x.13@[EMAIL PROTECTED]
>, Whole Lotta
Tom <Whathu@[EMAIL PROTECTED]
> wrote:

> 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.

   In addition, let me remind us of the *rule* about dropping 100 cfm
going to a single plane intake, something that appears to have been
forgotten these days. The Olds also had a Torker intake on it, and the
750 was suggested by Joe Mondello when he used to have his shop in Van
Nuys.

   This also prompted me to slap a 650DP on the second 302 I had built,
as opposed to the 750DP I had on the 289 before the Olds. Both small
blocks still have Torkers on them.

   I also have a pair of 3310's sitting around, so I could monkey with
one of those, too.

> 
> 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?
> 
>

-- 
CobraJet