[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 488: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 488: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 488: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 488: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 488: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 488: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 488: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 488: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 488: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 488: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 488: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 488: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 488: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 488: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 488: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 488: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 488: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 488: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 488: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 488: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 488: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 488: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 488: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 488: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 488: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 488: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 112: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 112: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 112: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 112: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 112: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 112: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/functions.php on line 4756: Cannot modify header information - headers already sent by (output started at [ROOT]/includes/functions.php:3891)
[phpBB Debug] PHP Warning: in file [ROOT]/includes/functions.php on line 4758: Cannot modify header information - headers already sent by (output started at [ROOT]/includes/functions.php:3891)
[phpBB Debug] PHP Warning: in file [ROOT]/includes/functions.php on line 4759: Cannot modify header information - headers already sent by (output started at [ROOT]/includes/functions.php:3891)
[phpBB Debug] PHP Warning: in file [ROOT]/includes/functions.php on line 4760: Cannot modify header information - headers already sent by (output started at [ROOT]/includes/functions.php:3891)
SpriteSpot.com • View topic - Which coil to buy?

Which coil to buy?

Have a Lucas question?

Which coil to buy?

Postby jedrake72 » Wed Apr 19, 2006 1:50 pm

I think I am in the market for a new coil. I read that you can test a coil by testing the resistance between the side posts and then one of the side posts and the center and mine is significantly out of spec (when I am able to get a good contact point to get a reading at all). That and it's the only piece of my ignition system that has not been replaced in the past 5 years.

I currently have a Bosch blue coil. I am running a Mallory dual points on a mostly stock 1972 with a 1275. I don't use the car for racing (yet) just the weekly cruise. That said, I have been having some issues with plug fowling so I want something stronger than stock.

Recommendations?
jedrake72
Pit Crew
 
Posts: 43
Joined: Tue Dec 13, 2005 4:55 pm
Location: San Jose, CA

Postby Charlie Tolman » Wed Apr 19, 2006 7:48 pm

On my old G/P and/or H/P '63 Sprite racecar, I had a Lucas sport coil, with a large diameter and with a screw-in high voltage connection. It worked fine.

In the quest for increased performance, I tried, upon recommendation by a speed shop, a Mallory (2440 ?) coil. With this coil, the electric tachometer went crazy, with the needle bouncing up and down. I learned later that this coil has a plastic case, not metal, and the un-shielded electro-magnetic radiation from the coil was affecting the tachometer.

I also had problems with the ignition cutting-out. This problem was traced to an external ballast resistor that had developed an internal crack, and would cause an intermittent circuit.

So, I next tried a MSD coil. The tachometer worked normal, but again, there eventually was a similar problem with another external ballast resistor.

You can probably guess what coil I used after these exercises. Yes, it was the Lucas sport coil, which does not need an external ballast resistor. This coil was used for many years, in engines with compression ratios up to 15:1 without problems.

The newer Lucas sport coils have a small diameter, and I do not know if they need an external balast resistor.

Charlie Tolman
Charlie Tolman
Judson Supercharged
 
Posts: 1199
Joined: Wed Mar 01, 2006 10:36 am
Location: Minnesota

Postby bugeye58 » Wed Apr 19, 2006 9:19 pm

Charlie, the current Sports Coils do not require the external resistor. And, they still work just fine.
Jeff
User avatar
bugeye58
948cc
 
Posts: 220
Joined: Mon Sep 06, 2004 1:11 pm
Location: Highland, Michigan

Postby admin » Sat Apr 22, 2006 6:46 pm

User avatar
admin
Site Admin
 
Posts: 766
Joined: Fri May 21, 2004 5:44 pm

Postby liamof » Tue Jun 20, 2006 6:22 pm

Liam
1960 bugeye project
1957 MGA daily driver
liamof
948cc
 
Posts: 111
Joined: Fri Feb 18, 2005 9:15 am
Location: Novato, California

Postby Charlie Tolman » Wed Jun 21, 2006 1:13 am

The electric power dissipated in the primary of the coil is V x V / R. where V is the voltage and R is the resistance. With 13 volts from the generator, and 3.6 ohms of primary resistance, the power dissipated is 47 watts.

The points are not closed all of the time, so the power dissipation will be less than 47 watts. A typical dwell angle for the points is 50 degrees out of a possible 90, which means that the points are closed about 55% of the time. This reduces the above power value to 26 watts. This should not make the coil hot.

Check the point gap, to determine if the gap is too small, which will cause a large dwell angle, thereby causing a larger average current through the coil primary. A typical point gap is 0.015", with an associated dwell angle of 50 degrees.

I do not know the designed operating temperature of the coil.

Charlie Tolman
H/P 40 (Retired)
Charlie Tolman
Judson Supercharged
 
Posts: 1199
Joined: Wed Mar 01, 2006 10:36 am
Location: Minnesota

Postby liamof » Thu Jun 22, 2006 1:21 pm

Thanks Charlie for your great overview of the ignition coil circuit. I have the points gap set at .015, and will be checking the dwel this weekend when I can get hold of a meter. I know the lucas sports coil is supposed to give you a hotter spark. Currently, I have NGK BP6ES spark plugs with the .025 gap. Should I increase the gap size on the plugs to accomodate for the hotter spark from the coil? Or should I just go back to the Champion N9YC plugs. Is there any heat range difference between these two plugs.
Or does any of that mattter?
I will also try replacing the wire from the coil to the distributor (white /black wire) to see if that helps.
The coil itself is hot to the touch, not exhaust manifold hot, but hot just the same. It might be just the nature of the beast since it has not let me down yet but I just don't want to fry my coil either. So if you can check with your car to see if the coil is hot to the touch or warm to the touch when it is running would help me alot.
Thanks, :?
Liam
1960 bugeye project
1957 MGA daily driver
liamof
948cc
 
Posts: 111
Joined: Fri Feb 18, 2005 9:15 am
Location: Novato, California

Postby drooartz » Fri Jun 23, 2006 8:08 am

Andrew Frink
1960 Austin Healey Sprite -- the Tunebug
http://www.drooartz.com
User avatar
drooartz
948cc
 
Posts: 148
Joined: Sun Sep 18, 2005 11:11 am
Location: Midway, Utah, USA

Postby Charlie Tolman » Sat Jun 24, 2006 10:47 am

Charlie Tolman
Judson Supercharged
 
Posts: 1199
Joined: Wed Mar 01, 2006 10:36 am
Location: Minnesota

Postby hpmowog » Sat Jun 24, 2006 12:47 pm

Karl Keiger
'62 Sprite
'60 Bugeye - Vintage Race Project
'65 Innocenti S - Vintage Race Project
hpmowog
948cc
 
Posts: 228
Joined: Sat Oct 30, 2004 3:24 pm
Location: Covington, LA

Postby Charlie Tolman » Sun Jun 25, 2006 1:24 am

Charlie Tolman
Judson Supercharged
 
Posts: 1199
Joined: Wed Mar 01, 2006 10:36 am
Location: Minnesota


Return to Electrical

Who is online

Users browsing this forum: No registered users and 1 guest

cron