Bosch Blue Coil

Every car has an electrical system. Here's the place to learn all about it.

Moderator: 2088 bob

Post Reply
DesertGuy
Posts: 2303
Joined: Sun Aug 27, 2006 9:45 pm

Bosch Blue Coil

Post by DesertGuy » Tue Dec 12, 2006 2:22 am

I recently came across this and found it an interesting read, it even references this site:

http://www.ratwell.com/technical/BlueCoil.html

In regards to the Bosch Blue Coil, is there a "wrong way" to mount them concerning their orientation? I have read that they should be mounted with the terminals facing down, and also, have read that it doesn't really matter... terminals can face up, down and sideways. I imagine this is having to do with keeping the ballast resistor or coils bathed internally, but was curious nonetheless.

Steve

Ol'fogasaurus
Posts: 13952
Joined: Tue Nov 14, 2006 1:17 am
Location: Just north of Seattle

Post by Ol'fogasaurus » Tue Dec 12, 2006 2:06 pm

I mount mine facing down so moisture has less of a chance to wick in the high tension lead hole. Also, the wires if they come off may not make accidental reconnections on the way to stopping. Funny story about that .....
Lee

My opinion is worth slightly less than what you paid for it.

User avatar
MNAirHead
Posts: 9570
Joined: Mon Sep 08, 2003 8:12 am

Post by MNAirHead » Tue Dec 12, 2006 4:40 pm

I just had a 6v leak the oil out and fail in one of our verts.. don't know if it would have failed if upward

User avatar
david58
Moderator
Posts: 14072
Joined: Sun Oct 23, 2005 8:14 pm
Location: Georgia near Savannah

Post by david58 » Tue Dec 12, 2006 6:21 pm

MNAirHead wrote:I just had a 6v leak the oil out and fail in one of our verts.. don't know if it would have failed if upward
I do believe that it only slows the problem down heat would eventually cause the coil to boil the oil out and end in failure because of the leakage.
Hot, humid air is less dense than cooler, drier air. This can allow a golf ball to fly through the air with greater ease, as there won't be as much resistance on the ball.

User avatar
fortyeye
Posts: 1346
Joined: Thu Apr 01, 2004 4:49 pm
Location: Bump City South-Oceanside, Ca.

Post by fortyeye » Tue Dec 12, 2006 7:05 pm

One really important point of Richard's article is the primary resistance. If you plan on using a electronic module in your dizzy (in place of points and condensor) check your primary resistance with an ohm meter. Measure between the two spade connections (with no wires attached)(+ and - primary) ... a reading of 3(+) ohms is good for the electronic module setup. If you have a coil without the ballast resistor (internally) you need to change the coil. It will read less than 3 ohms primary resistance and will fry the module.
AKA clearsurf

sagaboy
Posts: 1303
Joined: Mon Sep 13, 2004 2:04 am

Re:

Post by sagaboy » Wed Jan 15, 2014 9:11 am

fortyeye wrote:One really important point of Richard's article is the primary resistance. If you plan on using a electronic module in your dizzy (in place of points and condensor) check your primary resistance with an ohm meter. Measure between the two spade connections (with no wires attached)(+ and - primary) ... a reading of 3(+) ohms is good for the electronic module setup. If you have a coil without the ballast resistor (internally) you need to change the coil. It will read less than 3 ohms primary resistance and will fry the module.
Not quite true. I have been using an add on cheap $20 electronic point replacement I got from ebay and using a non-resistance coil for 9 years/daily drive and no problem (nine years ago the add on electronic point cost only $20 that they sell for $75 today).

sagaboy
Posts: 1303
Joined: Mon Sep 13, 2004 2:04 am

Re: Bosch Blue Coil

Post by sagaboy » Sun Oct 19, 2014 9:34 am

Bosch blue coil is suppose to produce a higher spark voltage of 18,000 volts and the original vw coil produces 12/14,000 volts and Bosch red coil produces 25,000 volts and some high performance coil like flame-thrower produces 40/50,000 volts.

Basically,
it all boils down to your spark plug gap setting, if your plug gap are set at 0.024 (for winter) or 0.028 (for summer) then it don't matter what coil you are using as the the spark plug gap will determine the sparking voltage that fires the plug as it only requires 10/11KV for a 0.024 gap or 12KV for a 0.028 plug gap. Therefore, even using a 50KV coil will not affect the "switching" contact point or an electronic module because as due to the plug gap setting the "switching" point will only handle 10/12KV

Post Reply