Bernd,
I had to design the IAC paths from "scratch", so I modified them (wouldnt
you?). I needed more meat to create a better path for the mani barrels. The
OEM path is designed for easy casting and provides a nice way to core the
casting for even wall thickness. Creates a bad flow separation area at the
rear of the bores as well...No need for that in Billet land. My handy
Snapon Scanner was crucial to verify that the different porting isnt causing
problems. A factory mechanic ( buddy of mine) was blown away at my desired
vs.actual IAC counts... Dead on. No nasty noises either. The IAC is a
strange animal. It does the basic job of making your truck idle (most of
the time at least) by sending air past the plates when closed... It also
operates during non-idle usage as well... The later the truck, the more it
does "off idle"... Its gotta work in all cases. I was trying to avoid nasty
noises for the most part, but I added some addtl idle stability as well with
the new TB design... Its not your "average" performance TB...
Bruce
----- Original Message -----
From: <bernd@texas.net>
To: <dakota-truck@buffnet.net>
Sent: Monday, October 09, 2000 2:05 PM
Subject: Re: DML: Intake manifold - Attn Bruce
>
> Bruce,
>
> Porting the IAC port?!? Won't that cause problems with the actual plunger
> (size and mating surface for the tip)?
>
> - Bernd
>
> > Steven
> > I havnt been able to figure out Hughes's CFM #s either... My SF600 cant
> > replicate their results. Im fully calibrated too. My results for F&B
> > products (very high flow V8 TBs) show the stocker wheezing out at 636
CFM @
> > 25" water, the Old F&B stage one flows 745 @ 25" water, and the billet
flows
> > 790cfm @ 25" water. IAC ports blacked. Id normally test at a lower
vacuum
> > (19"water), but I was trying to replicate the Hughes test #s. Maybe
Hughes
> > is flowing the TBs with the IAC ports WFO... If thats the case then Ill
> > start porting the IAC for super high performance idle characteristics...
> > J.K... I already port the IAC...yuk yuk yuk but seriously, If you add
IAC
> > flow, add about 100cfm. Thats why flow bench #s are so subjective user
to
> > user. Alas, I am awash in a sea of data and decisions....
> > Bruce
>
>
This archive was generated by hypermail 2b29 : Fri Jun 20 2003 - 11:55:55 EDT