Subject: Re: [TR] TR3 coil question

From: Anthony Rhodes <[email-masked]>
Date: Sat, 19 Sep 2015 13:35:21 -0500

That is can interesting question of why one coil was failing at high RPM while the other didn't.  

Assuming both are in proper operating condition, then I would expect that the one that can't sustain high RPM has a lot more inductance than the one that worked ok

As a matter of fact, the "high voltage" coils probably get that extra oomph by having higher inductance.  The price you pay for high inductance is that it takes longer to "charge" the magnetic field of the coil.  So, there is a steeper drop off of output voltage vs RPM.   

Do you have the specs on the two coils?  Btw the resistance of the secondary windings also has an influence.  So does the resistance of the primary windings though I am assuming both are 3 ohm.  

-Tony

Sent from my iPhone

> On Sep 19, 2015, at 1:00 PM, [email-masked] wrote:
> 
> Message: 1
> Date: Fri, 18 Sep 2015 14:26:04 -0400
> From: Jason Sukey <[email-masked]>
> To: [email-masked], [email-masked]
> Subject: Re: [TR] TR3 coil question
> Message-ID:
>    <[email-masked]>
> Content-Type: text/plain; charset="utf-8"
> 
> Andrew,
>    Not TR3 related, but I've had to play around with coils on my modified
> GT6 using the 123 distributor (USB tune model).  After a lot of fiddling, I
> found that with the recommended Bosch "blue" coil, it would "go flat" at
> high rpms when I was accelerating hard.  (this is compared to points dizzy
> with a hot coil).
> I ended up with the Bosch "red" coil (made in Brazil model, I'm told the
> made in Mexico version is of lesser quality).  This solved my problems and
> it once again is happy to pull strong up to 7,000 RPM's.
> 
> My theory is that the lower voltage "Blue" coil is fine for stock
> applications, but isn't enough for higher performance use.
> 
> Jason

** [email-masked] **

Archive: http://www.team.net/archive

---

From: Jason Sukey <[email-masked]>
Date: Sat, 19 Sep 2015 15:45:51 -0400

--===============4835569913577906419==

--047d7b4142f04d763c05201ee592

I don't have all the specs on me at the moment, but from memory, the
"hotter" red coil has a primary resistance of about 1.5 ohm, and the
"colder" coil had a primary resistance of 3 or 3.5 ohm.  My understanding
is this is the typical situation where the lesser coil can't develop enough
voltage at high rpm when the charge time is the shortest, thus needing the
increased voltage of the lower resistance coil.
Jason
On Sep 19, 2015 2:35 PM, "Anthony Rhodes" <[email-masked]> wrote:

> Assuming both are in proper operating condition, then I would expect that
> the one that can't sustain high RPM has a lot more inductance than the one
> that worked ok
>
> As a matter of fact, the "high voltage" coils probably get that extra
> oomph by having higher inductance.  The price you pay for high inductance
> is that it takes longer to "charge" the magnetic field of the coil.  So,
> there is a steeper drop off of output voltage vs RPM.
>
> Do you have the specs on the two coils?  Btw the resistance of the
> secondary windings also has an influence.  So does the resistance of the
> primary windings though I am assuming both are 3 ohm.
>
> -Tony
>
> Sent from my iPhone
>

--047d7b4142f04d763c05201ee592
Content-Transfer-Encoding: quoted-printable

<p dir=3D"ltr">I don&#39;t have all the specs on me at the moment, but from=
 memory, the &quot;hotter&quot; red coil has a primary resistance of about =
1.5 ohm, and the &quot;colder&quot; coil had a primary resistance of 3 or 3=
.5 ohm.=C2=A0 My understanding is this is the typical situation where the l=
esser coil can&#39;t develop enough voltage at high rpm when the charge tim=
e is the shortest, thus needing the increased voltage of the lower resistan=
ce coil.<br>
Jason</p>
<div class=3D"gmail_quote">On Sep 19, 2015 2:35 PM, &quot;Anthony Rhodes&qu=
ot; &lt;<a href=3D"mailto:[email-masked]">[email-masked]</a>&gt; =
wrote:<br type=3D"attribution"><blockquote class=3D"gmail_quote" style=3D"m=
argin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">That is can i=
nteresting question of why one coil was failing at high RPM while the other=
 didn&#39;t.<br>
<br>
Assuming both are in proper operating condition, then I would expect that t=
he one that can&#39;t sustain high RPM has a lot more inductance than the o=
ne that worked ok<br>
<br>
As a matter of fact, the &quot;high voltage&quot; coils probably get that e=
xtra oomph by having higher inductance.=C2=A0 The price you pay for high in=
ductance is that it takes longer to &quot;charge&quot; the magnetic field o=
f the coil.=C2=A0 So, there is a steeper drop off of output voltage vs RPM.=
<br>
<br>
Do you have the specs on the two coils?=C2=A0 Btw the resistance of the sec=
ondary windings also has an influence.=C2=A0 So does the resistance of the =
primary windings though I am assuming both are 3 ohm.<br>
<br>
-Tony<br>
<br>
Sent from my iPhone<br>
<br>
&gt; On Sep 19, 2015, at 1:00 PM, <a href=3D"mailto:triumphs-request@autox.=
team.net">[email-masked]</a> wrote:<br>
&gt;<br>
&gt; Message: 1<br>
&gt; Date: Fri, 18 Sep 2015 14:26:04 -0400<br>
&gt; From: Jason Sukey &lt;<a href=3D"mailto:[email-masked]">jsukey@gmail=
.com</a>&gt;<br>
&gt; To: <a href=3D"mailto:[email-masked]">[email-masked]=
et</a>, <a href=3D"mailto:[email-masked]">[email-masked]<=
/a><br>
&gt; Subject: Re: [TR] TR3 coil question<br>
&gt; Message-ID:<br>
&gt;=C2=A0 =C2=A0 &lt;<a href=3D"mailto:CAMmo4o-UUO%2BVMFaKgUCjZiOEQHs1zfsV=
[email-masked]">CAMmo4o-UUO+VMFaKgUCjZiOEQHs1zfsV6fArU=
[email-masked]</a>&gt;<br>
&gt; Content-Type: text/plain; charset=3D&quot;utf-8&quot;<br>
&gt;<br>
&gt; Andrew,<br>
&gt;=C2=A0 =C2=A0 Not TR3 related, but I&#39;ve had to play around with coi=
ls on my modified<br>
&gt; GT6 using the 123 distributor (USB tune model).=C2=A0 After a lot of f=
iddling, I<br>
&gt; found that with the recommended Bosch &quot;blue&quot; coil, it would =
&quot;go flat&quot; at<br>
&gt; high rpms when I was accelerating hard.=C2=A0 (this is compared to poi=
nts dizzy<br>
&gt; with a hot coil).<br>
&gt; I ended up with the Bosch &quot;red&quot; coil (made in Brazil model, =
I&#39;m told the<br>
&gt; made in Mexico version is of lesser quality).=C2=A0 This solved my pro=
blems and<br>
&gt; it once again is happy to pull strong up to 7,000 RPM&#39;s.<br>
&gt;<br>
&gt; My theory is that the lower voltage &quot;Blue&quot; coil is fine for =
stock<br>
&gt; applications, but isn&#39;t enough for higher performance use.<br>
&gt;<br>
&gt; Jason<br>
</blockquote></div>

--047d7b4142f04d763c05201ee592--

--===============4835569913577906419==
Content-Transfer-Encoding: 7bit
Content-Disposition: inline

--===============4835569913577906419==--

---

From: Anthony Rhodes <[email-masked]>
Date: Sat, 19 Sep 2015 17:07:36 -0500

--===============0356584020471951787==
Content-Transfer-Encoding: 7bit

--Apple-Mail-88BB55F8-28BB-4925-AD80-756963509334
	charset=us-ascii
Content-Transfer-Encoding: quoted-printable

1.5 ohm coils are typically used with a ballast resistor to make the overall=
 resistance about 3 ohms except when starting the engine.  A total resistanc=
e of less than 3 ohms may damage an electronic distributor switching unit un=
less it is specifically designed for low resistance coils. =20

I think that some racing applications, particularly 8 cylinder engines may u=
se a lower resistance ballast, or none at all.  But at low revs like 2500 on=
 a 4-cly, the peak current is too high for points and the usual electronic d=
istributor. =20

-Tony

Sent from my iPhone

> On Sep 19, 2015, at 2:45 PM, Jason Sukey <[email-masked]> wrote:
>=20
> I don't have all the specs on me at the moment, but from memory, the "hott=
er" red coil has a primary resistance of about 1.5 ohm, and the "colder" coi=
l had a primary resistance of 3 or 3.5 ohm.  My understanding is this is the=
 typical situation where the lesser coil can't develop enough voltage at hig=
h rpm when the charge time is the shortest, thus needing the increased volta=
ge of the lower resistance coil.
>=20
>> That is can interesting question of why one coil was failing at high RPM w=
hile the other didn't.
>>=20
>> Assuming both are in proper operating condition, then I would expect that=
 the one that can't sustain high RPM has a lot more inductance than the one t=
hat worked ok
>>=20
>> As a matter of fact, the "high voltage" coils probably get that extra oom=
ph by having higher inductance.  The price you pay for high inductance is th=
at it takes longer to "charge" the magnetic field of the coil.  So, there is=
 a steeper drop off of output voltage vs RPM.
>>=20
>> Do you have the specs on the two coils?  Btw the resistance of the second=
ary windings also has an influence.  So does the resistance of the primary w=
indings though I am assuming both are 3 ohm.
>>=20
>>=20
>>=20
>> >    <[email-masked]>=

>> > Content-Type: text/plain; charset=3D"utf-8"
>> >
>> > Andrew,
>> >    Not TR3 related, but I've had to play around with coils on my modifi=
ed
>> > GT6 using the 123 distributor (USB tune model).  After a lot of fiddlin=
g, I
>> > found that with the recommended Bosch "blue" coil, it would "go flat" a=
t
>> > high rpms when I was accelerating hard.  (this is compared to points di=
zzy
>> > with a hot coil).
>> > I ended up with the Bosch "red" coil (made in Brazil model, I'm told th=
e
>> > made in Mexico version is of lesser quality).  This solved my problems a=
nd
>> > applications, but isn't enough for higher performance use.

--Apple-Mail-88BB55F8-28BB-4925-AD80-756963509334
	charset=utf-8
Content-Transfer-Encoding: quoted-printable

<html><head><meta http-equiv=3D"content-type" content=3D"text/html; charset=3D=
utf-8"></head><body dir=3D"auto"><div>1.5 ohm coils are typically used with a=
 ballast resistor to make the overall resistance about 3 ohms except when st=
arting the engine. &nbsp;A total resistance of less than 3 ohms may damage a=
n electronic distributor switching unit unless it is specifically designed f=
or low resistance coils. &nbsp;</div><div><br></div><div>I think that some r=
acing applications, particularly 8 cylinder engines may use a lower resistan=
ce ballast, or none at all. &nbsp;But at low revs like 2500 on a 4-cly, the p=
eak current is too high for points and the usual electronic distributor. &nb=
sp;</div><div><br></div><div>-Tony<br><br>Sent from my iPhone</div><div><br>=
On Sep 19, 2015, at 2:45 PM, Jason Sukey &lt;<a href=3D"mailto:jsukey@gmail.=
com">[email-masked]</a>&gt; wrote:<br><br></div><blockquote type=3D"cite">=
<div><p dir=3D"ltr">I don't have all the specs on me at the moment, but from=
 memory, the "hotter" red coil has a primary resistance of about 1.5 ohm, an=
d the "colder" coil had a primary resistance of 3 or 3.5 ohm.&nbsp; My under=
standing is this is the typical situation where the lesser coil can't develo=
p enough voltage at high rpm when the charge time is the shortest, thus need=
ing the increased voltage of the lower resistance coil.<br>
Jason</p>
<div class=3D"gmail_quote">On Sep 19, 2015 2:35 PM, "Anthony Rhodes" &lt;<a h=
ref=3D"mailto:[email-masked]">[email-masked]</a>&gt; wrote:<br typ=
e=3D"attribution"><blockquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8=
ex;border-left:1px #ccc solid;padding-left:1ex">That is can interesting ques=
tion of why one coil was failing at high RPM while the other didn't.<br>
<br>
Assuming both are in proper operating condition, then I would expect that th=
e one that can't sustain high RPM has a lot more inductance than the one tha=
t worked ok<br>
<br>
As a matter of fact, the "high voltage" coils probably get that extra oomph b=
y having higher inductance.&nbsp; The price you pay for high inductance is t=
hat it takes longer to "charge" the magnetic field of the coil.&nbsp; So, th=
ere is a steeper drop off of output voltage vs RPM.<br>
<br>
Do you have the specs on the two coils?&nbsp; Btw the resistance of the seco=
ndary windings also has an influence.&nbsp; So does the resistance of the pr=
imary windings though I am assuming both are 3 ohm.<br>
<br>
-Tony<br>
<br>
Sent from my iPhone<br>
<br>
&gt; On Sep 19, 2015, at 1:00 PM, <a href=3D"mailto:[email-masked]=
eam.net">[email-masked]</a> wrote:<br>
&gt;<br>
&gt; Message: 1<br>
&gt; Date: Fri, 18 Sep 2015 14:26:04 -0400<br>
&gt; From: Jason Sukey &lt;<a href=3D"mailto:[email-masked]">jsukey@gmail.=
com</a>&gt;<br>
&gt; To: <a href=3D"mailto:[email-masked]">[email-masked]=
t</a>, <a href=3D"mailto:[email-masked]">[email-masked]</a=
&gt; Subject: Re: [TR] TR3 coil question<br>
&gt; Message-ID:<br>
&gt;&nbsp; &nbsp; &lt;<a href=3D"mailto:CAMmo4o-UUO%2BVMFaKgUCjZiOEQHs1zfsV6=
[email-masked]">CAMmo4o-UUO+VMFaKgUCjZiOEQHs1zfsV6fArUq9=
[email-masked]</a>&gt;<br>
&gt; Content-Type: text/plain; charset=3D"utf-8"<br>
&gt;<br>
&gt; Andrew,<br>
&gt;&nbsp; &nbsp; Not TR3 related, but I've had to play around with coils on=
 my modified<br>
&gt; GT6 using the 123 distributor (USB tune model).&nbsp; After a lot of fi=
ddling, I<br>
&gt; found that with the recommended Bosch "blue" coil, it would "go flat" a=
t<br>
&gt; high rpms when I was accelerating hard.&nbsp; (this is compared to poin=
ts dizzy<br>
&gt; with a hot coil).<br>
&gt; I ended up with the Bosch "red" coil (made in Brazil model, I'm told th=
e<br>
&gt; made in Mexico version is of lesser quality).&nbsp; This solved my prob=
lems and<br>
&gt; it once again is happy to pull strong up to 7,000 RPM's.<br>
&gt;<br>
&gt; My theory is that the lower voltage "Blue" coil is fine for stock<br>
&gt; applications, but isn't enough for higher performance use.<br>
&gt;<br>
&gt; Jason<br>
</blockquote></div>
</div></blockquote></body></html>=

--Apple-Mail-88BB55F8-28BB-4925-AD80-756963509334--

--===============0356584020471951787==
Content-Transfer-Encoding: 7bit
Content-Disposition: inline

--===============0356584020471951787==--

---

From: Jason Sukey <[email-masked]>
Date: Sat, 19 Sep 2015 20:48:27 -0400

--===============0973128634031520140==

--047d7bdc09e280d0840520231f06

Tony, you might not be familiar with the 123 ignition dizzys, but they
recommend 1 ohm or greater- no worries on that.

Jason
On Sep 19, 2015 7:52 PM, "Anthony Rhodes" <[email-masked]> wrote:

> 1.5 ohm coils are typically used with a ballast resistor to make the
> overall resistance about 3 ohms except when starting the engine.  A total
> resistance of less than 3 ohms may damage an electronic distributor
> switching unit unless it is specifically designed for low resistance coils.
>
>
> I think that some racing applications, particularly 8 cylinder engines may
> use a lower resistance ballast, or none at all.  But at low revs like 2500
> on a 4-cly, the peak current is too high for points and the usual
> electronic distributor.
>
> -Tony
>
> Sent from my iPhone
>

--047d7bdc09e280d0840520231f06
Content-Transfer-Encoding: quoted-printable

<p dir=3D"ltr">Tony, you might not be familiar with the 123 ignition dizzys=
, but they recommend 1 ohm or greater- no worries on that.</p>
<p dir=3D"ltr">Jason</p>
<div class=3D"gmail_quote">On Sep 19, 2015 7:52 PM, &quot;Anthony Rhodes&qu=
ot; &lt;<a href=3D"mailto:[email-masked]">[email-masked]</a>&gt; =
wrote:<br type=3D"attribution"><blockquote class=3D"gmail_quote" style=3D"m=
argin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir=3D"a=
uto"><div>1.5 ohm coils are typically used with a ballast resistor to make =
the overall resistance about 3 ohms except when starting the engine.=C2=A0 =
A total resistance of less than 3 ohms may damage an electronic distributor=
 switching unit unless it is specifically designed for low resistance coils=
. =C2=A0</div><div><br></div><div>I think that some racing applications, pa=
rticularly 8 cylinder engines may use a lower resistance ballast, or none a=
t all.=C2=A0 But at low revs like 2500 on a 4-cly, the peak current is too =
high for points and the usual electronic distributor. =C2=A0</div><div><br>=
</div><div>-Tony<br><br>Sent from my iPhone</div><div><br>On Sep 19, 2015, =
at 2:45 PM, Jason Sukey &lt;<a href=3D"mailto:[email-masked]" target=3D"_=
blank">[email-masked]</a>&gt; wrote:<br><br></div><blockquote type=3D"cit=
e"><div><p dir=3D"ltr">I don&#39;t have all the specs on me at the moment, =
but from memory, the &quot;hotter&quot; red coil has a primary resistance o=
f about 1.5 ohm, and the &quot;colder&quot; coil had a primary resistance o=
f 3 or 3.5 ohm.=C2=A0 My understanding is this is the typical situation whe=
re the lesser coil can&#39;t develop enough voltage at high rpm when the ch=
arge time is the shortest, thus needing the increased voltage of the lower =
resistance coil.<br>
Jason</p>
<div class=3D"gmail_quote">On Sep 19, 2015 2:35 PM, &quot;Anthony Rhodes&qu=
ot; &lt;<a href=3D"mailto:[email-masked]" target=3D"_blank">spamiam@co=
mcast.net</a>&gt; wrote:<br type=3D"attribution"><blockquote class=3D"gmail=
_quote" style=3D"margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:=
1ex">That is can interesting question of why one coil was failing at high R=
PM while the other didn&#39;t.<br>
<br>
Assuming both are in proper operating condition, then I would expect that t=
he one that can&#39;t sustain high RPM has a lot more inductance than the o=
ne that worked ok<br>
<br>
As a matter of fact, the &quot;high voltage&quot; coils probably get that e=
xtra oomph by having higher inductance.=C2=A0 The price you pay for high in=
ductance is that it takes longer to &quot;charge&quot; the magnetic field o=
f the coil.=C2=A0 So, there is a steeper drop off of output voltage vs RPM.=
<br>
<br>
Do you have the specs on the two coils?=C2=A0 Btw the resistance of the sec=
ondary windings also has an influence.=C2=A0 So does the resistance of the =
primary windings though I am assuming both are 3 ohm.<br>
<br>
-Tony<br>
<br>
Sent from my iPhone<br>
<br>
&gt; On Sep 19, 2015, at 1:00 PM, <a href=3D"mailto:triumphs-request@autox.=
team.net" target=3D"_blank">[email-masked]</a> wrote:<br>
&gt;<br>
&gt; Message: 1<br>
&gt; Date: Fri, 18 Sep 2015 14:26:04 -0400<br>
&gt; From: Jason Sukey &lt;<a href=3D"mailto:[email-masked]" target=3D"_b=
lank">[email-masked]</a>&gt;<br>
&gt; To: <a href=3D"mailto:[email-masked]" target=3D"_blank">aupr=
[email-masked]</a>, <a href=3D"mailto:[email-masked]" target=
=3D"_blank">[email-masked]</a><br>
&gt; Subject: Re: [TR] TR3 coil question<br>
&gt; Message-ID:<br>
&gt;=C2=A0 =C2=A0 &lt;<a href=3D"mailto:CAMmo4o-UUO%2BVMFaKgUCjZiOEQHs1zfsV=
[email-masked]" target=3D"_blank">CAMmo4o-UUO+VMFaKgUC=
[email-masked]</a>&gt;<br>
&gt; Content-Type: text/plain; charset=3D&quot;utf-8&quot;<br>
&gt;<br>
&gt; Andrew,<br>
&gt;=C2=A0 =C2=A0 Not TR3 related, but I&#39;ve had to play around with coi=
ls on my modified<br>
&gt; GT6 using the 123 distributor (USB tune model).=C2=A0 After a lot of f=
iddling, I<br>
&gt; found that with the recommended Bosch &quot;blue&quot; coil, it would =
&quot;go flat&quot; at<br>
&gt; high rpms when I was accelerating hard.=C2=A0 (this is compared to poi=
nts dizzy<br>
&gt; with a hot coil).<br>
&gt; I ended up with the Bosch &quot;red&quot; coil (made in Brazil model, =
I&#39;m told the<br>
&gt; made in Mexico version is of lesser quality).=C2=A0 This solved my pro=
blems and<br>
&gt; it once again is happy to pull strong up to 7,000 RPM&#39;s.<br>
&gt;<br>
&gt; My theory is that the lower voltage &quot;Blue&quot; coil is fine for =
stock<br>
&gt; applications, but isn&#39;t enough for higher performance use.<br>
&gt;<br>
&gt; Jason<br>
</blockquote></div>
</div></blockquote></div></blockquote></div>

--047d7bdc09e280d0840520231f06--

--===============0973128634031520140==
Content-Transfer-Encoding: 7bit
Content-Disposition: inline

--===============0973128634031520140==--