Subject: Re: [Fot] SU carb smooth bore or leave rough?

From: DAVE HOGYE via Fot <[email-masked]>
Date: Wed, 25 Nov 2020 08:34:25 -0800 (PST)

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I know that Huffaker does this.  I believe they also remove the damper oil and or the damper completely and shave down the throttle shaft to almost nothing.  So, I don't think you'd be trashing them, but I don't know what the dyno results are either. As far as I know, they also replace head gaskets and engines quite regularly on their BMC builds.  
Dave H. 

On 11/24/2020 12:41 PM Mike Harmuth via Fot <[email-masked]> wrote:

>      
>      
>     I was going over my race carbs (SU H4)and wondered if there's anything to be gained  (or lost) by smoothing out the casting (before the jet)? I'm not sure if it's designed (or left) that way to promote turbulence and better mixing as the air flows over the jet or if polishing it down would help.
>      
>     I'd hate to trash a pair of good carbs before I get some answers.
>      
>     thanks
>     mike h
>     _______________________________________________
>     [email-masked]
> 
>     http://www.fot-racing.com
> 
>     Donate: http://www.team.net/donate.html
>     Archive: http://autox.team.net/archive http://www.team.net/pipermail/fot
>     Unsubscribe/Manage: http://autox.team.net/mailman/options/fot/[email-masked]
> 
> 
> 

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 <body>
  <div style="font-size: 12pt; font-family: helvetica,arial,sans-serif; color: #333333;">
   <span style="font-family: helvetica; font-size: 12pt;">I know that Huffaker does this.&nbsp; I believe they also remove the damper oil and or the damper completely and shave down the throttle shaft to almost nothing.&nbsp; So, I don't think you'd be trashing them, but I don't know what the dyno results are either. As far as I know, they also replace head gaskets and engines quite regularly on their BMC builds.&nbsp;&nbsp;</span>
  </div> 
  <div style="font-size: 12pt; font-family: helvetica,arial,sans-serif; color: #333333;">
   <span style="font-family: helvetica; font-size: 12pt;">Dave H.&nbsp;</span>
  </div> 
  <div style="font-size: 12pt; font-family: helvetica,arial,sans-serif; color: #333333;">
   &nbsp;
  </div> 
  <div style="font-size: 12pt; font-family: helvetica,arial,sans-serif; color: #333333;">
   &nbsp;
  </div> 
  <div style="font-size: 12pt; font-family: helvetica,arial,sans-serif; color: #333333;">
   On 11/24/2020 12:41 PM Mike Harmuth via Fot &lt;[email-masked]&gt; wrote:
  </div> 
  <blockquote type="cite"> 
   <div>
    &nbsp;
   </div> 
   <div>
    &nbsp;
   </div> 
   <div dir="ltr">
    I was going over my race carbs (SU H4)and wondered if there's anything to be gained&nbsp; (or lost) by smoothing out the casting (before the jet)? I'm not sure if it's designed (or left) that way to promote turbulence and better mixing as the air flows over the jet or if polishing it down would help. 
    <div>
     &nbsp;
    </div> 
    <div>
     I'd hate to trash a pair of good carbs before I get some answers.
    </div> 
    <div>
     &nbsp;
    </div> 
    <div>
     thanks
    </div> 
    <div>
     mike h
    </div> 
   </div> _______________________________________________
   <br>[email-masked]
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From: David Gott via Fot <[email-masked]>
Date: Wed, 25 Nov 2020 17:01:34 +0000 (UTC)

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Hi Mike,
My TR4 came with a pair of Computune set up HS6=E2=80=99s that have had the=
 damper removed, and the whole bridge at the jet removed. =C2=A0The jet sta=
nds alone on its own, sticking up the height of the former bridge.=C2=A0 Al=
so, the throttle shafts are Steel, and very thin, only picking up the throt=
tle plate on one side. =C2=A0Alas, the steel has worn out the aluminum body=
 and needs bushings badly. =C2=A0I=E2=80=99m sure they flow great, but with=
out the bridge, probably tough to drive at anything other than WOT. =C2=A0 =
I bet part throttle modulation is difficult, but good dyno numbers are sure=
 to be there.... =C2=A0I will try them some day! =C2=A0Anyone have experien=
ce running the Computune carbs?=C2=A0=C2=A0
Dave Gott

Sent from Yahoo Mail for iPhone

On Wednesday, November 25, 2020, 11:34 AM, DAVE HOGYE via Fot <[email-masked]=
am.net> wrote:

  I know that Huffaker does this.=C2=A0 I believe they also remove the damp=
er oil and or the damper completely and shave down the throttle shaft to al=
most nothing.=C2=A0 So, I don't think you'd be trashing them, but I don't k=
now what the dyno results are either. As far as I know, they also replace h=
ead gaskets and engines quite regularly on their BMC builds.=C2=A0=C2=A0   =
Dave H.=C2=A0   =C2=A0   =C2=A0   On 11/24/2020 12:41 PM Mike Harmuth via F=
ot <[email-masked]> wrote: =20
  =C2=A0   =C2=A0   I was going over my race carbs (SU H4)and wondered if t=
here's anything to be gained=C2=A0 (or lost) by smoothing out the casting (=
before the jet)? I'm not sure if it's designed (or left) that way to promot=
e turbulence and better mixing as the air flows over the jet or if polishin=
g it down would help.  =C2=A0   I'd hate to trash a pair of good carbs befo=
re I get some answers.   =C2=A0   thanks   mike h   _______________________=
________________________=20
[email-masked]=20
=20
http://www.fot-racing.com=20
=20
Archive: http://autox.team.net/archive http://www.team.net/pipermail/fot=20
st.net=20
=20
=20
=20
 _______________________________________________
[email-masked]

hoo.com

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<html xmlns=3D"http://www.w3.org/1999/xhtml" xmlns:v=3D"urn:schemas-microso=
ft-com:vml" xmlns:o=3D"urn:schemas-microsoft-com:office:office"><head><!--[=
if gte mso 9]><xml><o:OfficeDocumentSettings><o:AllowPNG/><o:PixelsPerInch>=
96</o:PixelsPerInch></o:OfficeDocumentSettings></xml><![endif]--></head><bo=
dy>
Hi Mike,<div><br></div><div>My TR4 came with a pair of Computune set up HS6=
=E2=80=99s that have had the damper removed, and the whole bridge at the je=
t removed. &nbsp;The jet stands alone on its own, sticking up the height of=
 the former bridge.&nbsp; Also, the throttle shafts are Steel, and very thi=
n, only picking up the throttle plate on one side. &nbsp;Alas, the steel ha=
s worn out the aluminum body and needs bushings badly. &nbsp;I=E2=80=99m su=
re they flow great, but without the bridge, probably tough to drive at anyt=
hing other than WOT. &nbsp; I bet part throttle modulation is difficult, bu=
t good dyno numbers are sure to be there.... &nbsp;I will try them some day=
! &nbsp;Anyone have experience running the Computune carbs?&nbsp;&nbsp;</di=
v><div><br></div><div>Dave Gott<br><br><br><a href=3D"https://overview.mail=
.yahoo.com/?.src=3DiOS">Sent from Yahoo Mail for iPhone</a><br><br><p class=
=3D"yahoo-quoted-begin" style=3D"font-size: 15px; color: #715FFA; padding-t=
op: 15px; margin-top: 0">On Wednesday, November 25, 2020, 11:34 AM, DAVE HO=
GYE via Fot &lt;[email-masked]&gt; wrote:</p><blockquote class=3D"iosym=
ail"><div id=3D"yiv4410313316"><div>
  <div style=3D"font-size:12pt;font-family:helvetica, arial, sans-serif;col=
or:#333333;">
   <span style=3D"font-family:helvetica;font-size:12pt;">I know that Huffak=
er does this.&nbsp; I believe they also remove the damper oil and or the da=
mper completely and shave down the throttle shaft to almost nothing.&nbsp; =
So, I don't think you'd be trashing them, but I don't know what the dyno re=
sults are either. As far as I know, they also replace head gaskets and engi=
nes quite regularly on their BMC builds.&nbsp;&nbsp;</span>
  </div>=20
  <div style=3D"font-size:12pt;font-family:helvetica, arial, sans-serif;col=
or:#333333;">
   <span style=3D"font-family:helvetica;font-size:12pt;">Dave H.&nbsp;</spa=
n>
  </div>=20
  <div style=3D"font-size:12pt;font-family:helvetica, arial, sans-serif;col=
or:#333333;">
   &nbsp;
  </div>=20
  <div style=3D"font-size:12pt;font-family:helvetica, arial, sans-serif;col=
or:#333333;">
   &nbsp;
  </div>=20
  <div class=3D"yiv4410313316yqt1393280786" id=3D"yiv4410313316yqt59346"><d=
iv style=3D"font-size:12pt;font-family:helvetica, arial, sans-serif;color:#=
333333;">
   On 11/24/2020 12:41 PM Mike Harmuth via Fot &lt;[email-masked]&gt; w=
rote:
  </div>=20
  <blockquote type=3D"cite">=20
   <div>
    &nbsp;
   </div>=20
   <div>
    &nbsp;
   </div>=20
   <div dir=3D"ltr">
    I was going over my race carbs (SU H4)and wondered if there's anything =
to be gained&nbsp; (or lost) by smoothing out the casting (before the jet)?=
 I'm not sure if it's designed (or left) that way to promote turbulence and=
 better mixing as the air flows over the jet or if polishing it down would =
help.=20
    <div>
     &nbsp;
    </div>=20
    <div>
     I'd hate to trash a pair of good carbs before I get some answers.
    </div>=20
    <div>
     &nbsp;
    </div>=20
    <div>
     thanks
    </div>=20
    <div>
     mike h
    </div>=20
   </div> _______________________________________________
   <br clear=3D"none">[email-masked]
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  </blockquote></div>=20
 </div></div><div class=3D"yqt1393280786" id=3D"yqt35642">_________________=
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From: Tony and Annie Garmey via Fot <[email-masked]>
Date: Wed, 25 Nov 2020 17:27:49 +0000

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From: Bruce Stutzman via Fot <[email-masked]>
Date: Wed, 25 Nov 2020 12:34:34 -0500

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Back in the day we thought we needed the bridge to help mix the incoming
air with the fuel.
Bruce

On Wed, Nov 25, 2020 at 12:04 PM David Gott via Fot <[email-masked]>
wrote:

> Hi Mike,
>
> My TR4 came with a pair of Computune set up HS6=E2=80=99s that have had t=
he damper
> removed, and the whole bridge at the jet removed.  The jet stands alone o=
n
> its own, sticking up the height of the former bridge.  Also, the throttle
> shafts are Steel, and very thin, only picking up the throttle plate on on=
e
> side.  Alas, the steel has worn out the aluminum body and needs bushings
> badly.  I=E2=80=99m sure they flow great, but without the bridge, probabl=
y tough to
> drive at anything other than WOT.   I bet part throttle modulation is
> difficult, but good dyno numbers are sure to be there....  I will try the=
m
> some day!  Anyone have experience running the Computune carbs?
>
> Dave Gott
>
>
> <https://overview.mail.yahoo.com/?.src=3DiOS>
>
> On Wednesday, November 25, 2020, 11:34 AM, DAVE HOGYE via Fot <
> [email-masked]> wrote:
>
> I know that Huffaker does this.  I believe they also remove the damper oi=
l
> and or the damper completely and shave down the throttle shaft to almost
> nothing.  So, I don't think you'd be trashing them, but I don't know what
> the dyno results are either. As far as I know, they also replace head
> gaskets and engines quite regularly on their BMC builds.
> Dave H.
>
>
> I was going over my race carbs (SU H4)and wondered if there's anything to
> be gained  (or lost) by smoothing out the casting (before the jet)? I'm n=
ot
> sure if it's designed (or left) that way to promote turbulence and better
> mixing as the air flows over the jet or if polishing it down would help.
>
> Unsubscribe/Manage:
> http://autox.team.net/mailman/options/fot/[email-masked]
>
>
> Unsubscribe/Manage:
> http://autox.team.net/mailman/options/fot/[email-masked]
>
>
> Unsubscribe/Manage <http://www.team.net/pipermail/fotUnsubscribe/Manage>:
> http://autox.team.net/mailman/options/fot/[email-masked]
>
>
>

--000000000000f5959a05b4f1d749
Content-Transfer-Encoding: quoted-printable

<div dir=3D"ltr">Back in the day we thought we needed the bridge to help mi=
x the incoming air with the fuel.<div>Bruce</div></div><br><div class=3D"gm=
ail_quote"><div dir=3D"ltr" class=3D"gmail_attr">On Wed, Nov 25, 2020 at 12=
:04 PM David Gott via Fot &lt;<a href=3D"mailto:[email-masked]">fot@aut=
ox.team.net</a>&gt; wrote:<br></div><blockquote class=3D"gmail_quote" style=
=3D"margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding=
-left:1ex"><div>
Hi Mike,<div><br></div><div>My TR4 came with a pair of Computune set up HS6=
=E2=80=99s that have had the damper removed, and the whole bridge at the je=
t removed.=C2=A0 The jet stands alone on its own, sticking up the height of=
 the former bridge.=C2=A0 Also, the throttle shafts are Steel, and very thi=
n, only picking up the throttle plate on one side.=C2=A0 Alas, the steel ha=
s worn out the aluminum body and needs bushings badly.=C2=A0 I=E2=80=99m su=
re they flow great, but without the bridge, probably tough to drive at anyt=
hing other than WOT. =C2=A0 I bet part throttle modulation is difficult, bu=
t good dyno numbers are sure to be there....=C2=A0 I will try them some day=
!=C2=A0 Anyone have experience running the Computune carbs?=C2=A0=C2=A0</di=
v><div><br></div><div>Dave Gott<br><br><br><a href=3D"https://overview.mail=
.yahoo.com/?.src=3DiOS" target=3D"_blank">Sent from Yahoo Mail for iPhone</=
a><br><br><p style=3D"font-size:15px;color:rgb(113,95,250);padding-top:15px=
;margin-top:0px">On Wednesday, November 25, 2020, 11:34 AM, DAVE HOGYE via =
Fot &lt;<a href=3D"mailto:[email-masked]" target=3D"_blank">[email-masked]=
eam.net</a>&gt; wrote:</p><blockquote><div id=3D"gmail-m_445302584176418828=
9yiv4410313316"><div>
  <div style=3D"font-size:12pt;font-family:helvetica,arial,sans-serif;color=
:rgb(51,51,51)">
   <span style=3D"font-family:helvetica;font-size:12pt">I know that Huffake=
r does this.=C2=A0 I believe they also remove the damper oil and or the dam=
per completely and shave down the throttle shaft to almost nothing.=C2=A0 S=
o, I don&#39;t think you&#39;d be trashing them, but I don&#39;t know what =
the dyno results are either. As far as I know, they also replace head gaske=
ts and engines quite regularly on their BMC builds.=C2=A0=C2=A0</span>
  </div>=20
  <div style=3D"font-size:12pt;font-family:helvetica,arial,sans-serif;color=
:rgb(51,51,51)">
   <span style=3D"font-family:helvetica;font-size:12pt">Dave H.=C2=A0</span=
  </div>=20
  <div style=3D"font-size:12pt;font-family:helvetica,arial,sans-serif;color=
:rgb(51,51,51)">
   =C2=A0
  </div>=20
  <div style=3D"font-size:12pt;font-family:helvetica,arial,sans-serif;color=
:rgb(51,51,51)">
   =C2=A0
  </div>=20
  <div id=3D"gmail-m_4453025841764188289yiv4410313316yqt59346"><div style=
=3D"font-size:12pt;font-family:helvetica,arial,sans-serif;color:rgb(51,51,5=
1)">
   On 11/24/2020 12:41 PM Mike Harmuth via Fot &lt;<a href=3D"mailto:fot@au=
tox.team.net" target=3D"_blank">[email-masked]</a>&gt; wrote:
  </div>=20
  <blockquote type=3D"cite">=20
   <div>
    =C2=A0
   </div>=20
   <div>
    =C2=A0
   </div>=20
   <div dir=3D"ltr">
    I was going over my race carbs (SU H4)and wondered if there&#39;s anyth=
ing to be gained=C2=A0 (or lost) by smoothing out the casting (before the j=
et)? I&#39;m not sure if it&#39;s designed (or left) that way to promote tu=
rbulence and better mixing as the air flows over the jet or if polishing it=
 down would help.=20
    <div>
     =C2=A0
    </div>=20
    <div>
     I&#39;d hate to trash a pair of good carbs before I get some answers.
    </div>=20
    <div>
     =C2=A0
    </div>=20
    <div>
     thanks
    </div>=20
    <div>
     mike h
    </div>=20
   </div> _______________________________________________
   <br clear=3D"none"><a href=3D"mailto:[email-masked]" target=3D"_blan=
k">[email-masked]</a>
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From: Enquiries Road & Track via Fot <[email-masked]>
Date: Thu, 26 Nov 2020 07:55:55 +1000

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--00000000000055125605b4f5738f

I have had a few goes at shaving throttle shafts with very mixed
results..typically fracturing where they meet the carby body.  if you
planned to change them routinely, thats not such an issue

Some recent flow bench work leaves me wondering completely about the wisdom
of any of this without real-world testing

We found some head/intake arrangements where the air flow was too high in
certain places and we had to dimple the port to slow it down. Sometimes,
just enlarging the port does not work as intended

The very best SU research ive seen was done by David Vizard . There are
plenty of on-line references to his work, but if anyone can't find what
they want, i can scan relevant parts of his text book (tome) on tuning BMC
A series engines. Ive used his analysis on  various shapes of ram tubes for
many years

of far more importance seems to be the distance from the valve to the
throttle plate, with the ideal varying considerably with the RPM range
being used. As a general comment, it seems like many folk have it far too
long

I have proven that fiddling with the damper in a SU has a dramatic effect
on throttle response, and not always what you think. i'll offer the comment
that its very engine set-up specific. Sadly, this aspect is all-but
impossible to test on a conventional flow bench

Terry
Australia

On Thu, Nov 26, 2020 at 2:35 AM DAVE HOGYE via Fot <[email-masked]>
wrote:

> I know that Huffaker does this.  I believe they also remove the damper oil
> be gained  (or lost) by smoothing out the casting (before the jet)? I'm not
> http://autox.team.net/mailman/options/fot/[email-masked]
>
>
>

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<div dir=3D"ltr">I have had a few goes at shaving throttle shafts with very=
 mixed results..typically fracturing where they meet=C2=A0the carby body.=
=C2=A0 if you planned to change them routinely, thats not such an issue<div=
><br><div>Some recent flow bench work leaves me wondering completely=C2=A0a=
bout the wisdom of any of this without=C2=A0real-world testing<br></div><di=
v><br></div><div>We found some head/intake arrangements=C2=A0where the air =
flow was too high in certain places and we had to dimple the port to slow i=
t down. Sometimes, just=C2=A0enlarging the port does not work as intended</=
div><div><br></div><div>The very best SU research ive seen was done by Davi=
d Vizard . There are plenty of on-line references to his work, but if anyon=
e can&#39;t find what they want, i can scan relevant parts of his text book=
 (tome) on tuning BMC A series engines. Ive=C2=A0used his analysis on=C2=A0=
 various shapes of ram tubes for many years</div><div><br></div><div>of far=
 more importance seems to be the distance from the valve to the throttle pl=
ate, with the ideal varying considerably=C2=A0with the RPM range being used=
. As a general comment, it seems like many folk have it far too long=C2=A0<=
/div><div><br></div><div><div>I have proven that fiddling with the damper i=
n a SU has a dramatic effect on throttle response, and not always what you =
think. i&#39;ll offer the comment that its very engine set-up specific. Sad=
ly, this aspect is all-but impossible to test on a conventional flow bench<=
/div></div><div><div><div dir=3D"ltr" class=3D"gmail_signature" data-smartm=
ail=3D"gmail_signature"><div dir=3D"ltr"><div><div dir=3D"ltr"><div><div di=
r=3D"ltr"><div><div dir=3D"ltr"><div><div dir=3D"ltr"><div><div dir=3D"ltr"=
><div><br></div><div>Terry</div><div>Australia<br><br></div></div></div></d=
iv></div></div></div></div></div></div></div></div></div></div><br></div></=
div></div><br><div class=3D"gmail_quote"><div dir=3D"ltr" class=3D"gmail_at=
tr">On Thu, Nov 26, 2020 at 2:35 AM DAVE HOGYE via Fot &lt;<a href=3D"mailt=
o:[email-masked]">[email-masked]</a>&gt; wrote:<br></div><blockquot=
e class=3D"gmail_quote" style=3D"margin:0px 0px 0px 0.8ex;border-left:1px s=
olid rgb(204,204,204);padding-left:1ex"><u></u>

 =20
  =20
=20
 <div>
  </div>=20
  <div style=3D"font-size:12pt;font-family:helvetica,arial,sans-serif;color=
:rgb(51,51,51)">
   =C2=A0
  </div>=20
  <div style=3D"font-size:12pt;font-family:helvetica,arial,sans-serif;color=
:rgb(51,51,51)">
   =C2=A0
  </div>=20
  <div style=3D"font-size:12pt;font-family:helvetica,arial,sans-serif;color=
:rgb(51,51,51)">
   On 11/24/2020 12:41 PM Mike Harmuth via Fot &lt;<a href=3D"mailto:fot@au=
tox.team.net" target=3D"_blank">[email-masked]</a>&gt; wrote:
  </div>=20
  <blockquote type=3D"cite">=20
   <div>
    =C2=A0
   </div>=20
   <div>
    =C2=A0
   </div>=20
   <div dir=3D"ltr">
    I was going over my race carbs (SU H4)and wondered if there&#39;s anyth=
ing to be gained=C2=A0 (or lost) by smoothing out the casting (before the j=
et)? I&#39;m not sure if it&#39;s designed (or left) that way to promote tu=
rbulence and better mixing as the air flows over the jet or if polishing it=
 down would help.=20
    <div>
     =C2=A0
    </div>=20
    <div>
     I&#39;d hate to trash a pair of good carbs before I get some answers.
    </div>=20
    <div>
     =C2=A0
    </div>=20
    <div>
     thanks
    </div>=20
    <div>
     mike h
    </div>=20
   </div> _______________________________________________
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   <br>
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  </blockquote>=20
 </div>
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From: Mike Harmuth via Fot <[email-masked]>
Date: Wed, 25 Nov 2020 19:59:56 -0500

--===============7723212691049562485==

--000000000000bc36b405b4f810da

Thanks to everyone for their insights. I think I'll just look for any
obvious rough spots but mostly leave well enough alone.

mike h

On Wed, Nov 25, 2020 at 4:52 PM Enquiries Road & Track <
[email-masked]> wrote:

> Some recent flow bench work leaves me wondering completely about the
> wisdom of any of this without real-world testing
>
>> I know that Huffaker does this.  I believe they also remove the damper
>> oil and or the damper completely and shave down the throttle shaft to
>> almost nothing.  So, I don't think you'd be trashing them, but I don't know
>> what the dyno results are either. As far as I know, they also replace head

--000000000000bc36b405b4f810da
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<div dir=3D"ltr">Thanks to everyone for their insights. I think I&#39;ll ju=
st look for any obvious rough spots but mostly leave well enough alone.<div=
><br></div><div>mike h</div></div><br><div class=3D"gmail_quote"><div dir=
=3D"ltr" class=3D"gmail_attr">On Wed, Nov 25, 2020 at 4:52 PM Enquiries Roa=
d &amp; Track &lt;<a href=3D"mailto:[email-masked]">enquirie=
[email-masked]</a>&gt; wrote:<br></div><blockquote class=3D"gmail_qu=
ote" style=3D"margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,20=
4);padding-left:1ex"><div dir=3D"ltr">I have had a few goes at shaving thro=
ttle shafts with very mixed results..typically fracturing where they meet=
=C2=A0the carby body.=C2=A0 if you planned to change them routinely, thats =
not such an issue<div><br><div>Some recent flow bench work leaves me wonder=
ing completely=C2=A0about the wisdom of any of this without=C2=A0real-world=
 testing<br></div><div><br></div><div>We found some head/intake arrangement=
s=C2=A0where the air flow was too high in certain places and we had to dimp=
le the port to slow it down. Sometimes, just=C2=A0enlarging the port does n=
ot work as intended</div><div><br></div><div>The very best SU research ive =
seen was done by David Vizard . There are plenty of on-line references to h=
is work, but if anyone can&#39;t find what they want, i can scan relevant p=
arts of his text book (tome) on tuning BMC A series engines. Ive=C2=A0used =
his analysis on=C2=A0 various shapes of ram tubes for many years</div><div>=
<br></div><div>of far more importance seems to be the distance from the val=
ve to the throttle plate, with the ideal varying considerably=C2=A0with the=
 RPM range being used. As a general comment, it seems like many folk have i=
t far too long=C2=A0</div><div><br></div><div><div>I have proven that fiddl=
ing with the damper in a SU has a dramatic effect on throttle response, and=
 not always what you think. i&#39;ll offer the comment that its very engine=
 set-up specific. Sadly, this aspect is all-but impossible to test on a con=
ventional flow bench</div></div><div><div><div dir=3D"ltr"><div dir=3D"ltr"=
><div><div dir=3D"ltr"><div><div dir=3D"ltr"><div><div dir=3D"ltr"><div><di=
v dir=3D"ltr"><div><div dir=3D"ltr"><div><br></div><div>Terry</div><div>Aus=
tralia<br><br></div></div></div></div></div></div></div></div></div></div><=
/div></div></div></div><br></div></div></div><br><div class=3D"gmail_quote"=
><div dir=3D"ltr" class=3D"gmail_attr">On Thu, Nov 26, 2020 at 2:35 AM DAVE=
 HOGYE via Fot &lt;<a href=3D"mailto:[email-masked]" target=3D"_blank">=
[email-masked]</a>&gt; wrote:<br></div><blockquote class=3D"gmail_quote=
" style=3D"margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);=
padding-left:1ex"><u></u>

 =20
  =20
=20
 <div>
  </div>=20

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