Indexing Spark Plugs - Kawasaki Vulcan 750 Forum : Kawasaki VN750 Forums
Electrical
Where does this wire go?
Includes Electrical mods, Lights, Stator,
Rectifier, Diagrams, etc

 5Likes
  • 1 Post By Spockster
  • 1 Post By Spockster
  • 1 Post By MSattler
  • 2 Post By michiganteddybear
 
LinkBack Thread Tools Display Modes
post #1 of 5 (permalink) Old 05-20-2020, 05:38 PM Thread Starter
Senior Member
 
Jason Pittenger's Avatar
 
Join Date: Apr 2018
Location: Northern Illinois (Not Chicago)
Posts: 373
iTrader: (0)
 
Garage
Indexing Spark Plugs

Has anyone tried this?
If you don't know what this is, it's adding shims to the spark plugs so that the position of the ground strap is controlled.

Looking at the plug location in the cylinder head, I would guess that having the open side pointed downward would provide a better flame expansion path, vs point down or to the side.
Maybe point the open side down and towards the intake (45 degrees)?
Maybe towards the intake valves?
The theory two fold:
1. The ground strap impedes the growth of the flame, so you want to put that towards the shortest path in the cylinder.
2. The ground strap impedes the air/fuel from reaching the plug, so you put it away from the intake valves.

I can get a 50 pack of 0.01" shims for $23.
Each shim rotates the plug between 52 and 61 degrees (uncertainty is because I don't recall if the plugs are fine or course thread).

Looking online, consensus is anywhere from 0-4% HP and 0-2% MPG gains.
No one says it that it makes things worse. Many say that it makes no improvements.
But I'm an engineer so if I can get 0.5% each from 20 different mods, I'm suddenly up 10% HP!
(One can dream, right? )
Attached Thumbnails
Click image for larger version

Name:	Cylinder Head.jpg
Views:	11
Size:	99.5 KB
ID:	47837   Click image for larger version

Name:	Cylinder Head 2.jpg
Views:	11
Size:	28.2 KB
ID:	47839  


'89 VN750 Bought stock 4/12/18 @ 17805.9 miles $800. Wrecked once. 27454.5+ miles

Completed modifications:
Removed mufflers, straight pipes out of GB. 110/90 Front Tire. Pick-up coil mod. Shindengen MOSFET FH020AA r/r. USB Outlet + Voltmeter. Repainted Metallic Blue w/ new tank bages. Ear Shave (wo/ coasters) 40/140 NO shims 45MPG. MCCT conversion.

Planned modifications:
Custom LED turn signals. Windshield. Highway Pegs. (Possible) ignition adv. Tuxedo Mod. Ignition coil mod.
Jason Pittenger is offline  
Sponsored Links
Advertisement
 
post #2 of 5 (permalink) Old 05-20-2020, 05:55 PM
Senior Member
 
Spockster's Avatar
 
Join Date: Nov 2012
Location: WV
Posts: 7,262
iTrader: (5)
   
Very miniscule gain, nothing you'll feel.

I'd save it for last, after nitrous, blower, turbo, and intercooler, along with every go-fast mod in the Jegs catalog. 🙂

It's one of the last efforts to shave 1/1000 off your ET.
MSattler likes this.

2003-21k mi
Shaved w/UniPK92+Stock Jets-TPE/MOSFET-Shinko Tires-AGM batt-bags-chrome-LEDs...more
__________________________________________________ ____________
Repair Manual: http://www.mediafire.com/file/mj7z81..._Catalogue.pdf

Owner's Manual: http://www.mediafire.com/file/nscb5f...ers+Manual.pdf
Spockster is offline  
post #3 of 5 (permalink) Old 05-21-2020, 12:05 AM
Senior Member
 
Spockster's Avatar
 
Join Date: Nov 2012
Location: WV
Posts: 7,262
iTrader: (5)
   
More gain than I thought, 1 or 2 horsepower on a V8, according to this dude from Summit.
https://youtu.be/Ys4GnIk_YC0
MSattler likes this.

2003-21k mi
Shaved w/UniPK92+Stock Jets-TPE/MOSFET-Shinko Tires-AGM batt-bags-chrome-LEDs...more
__________________________________________________ ____________
Repair Manual: http://www.mediafire.com/file/mj7z81..._Catalogue.pdf

Owner's Manual: http://www.mediafire.com/file/nscb5f...ers+Manual.pdf
Spockster is offline  
 
post #4 of 5 (permalink) Old 05-21-2020, 08:09 AM
Senior Member
 
MSattler's Avatar
 
Join Date: Jun 2019
Location: Iowa
Posts: 259
iTrader: (0)
 
1 or 2 hp? That's essentially a difference in humidity.
Spockster likes this.

'08 Road King Classic
'86 VN750:
Ear Shave, K&N Filters, Mean Streak Seat, AGM battery, Blue Wire Mod, Pick-up Coil Mod, Timing Advance Mod, NGK Iridium Plugs and Wire, LEDs, Bed Liner Paint Job, Over-sized Tires, New Brakes, New Fork Seals, Progressive Springs, Kick Stand Mod, Highway Pegs, 40/140 No Shims, Vance & Hines Exhaust, New Grips, Extra Wide Emgo Handle Bars
John 8:44, REV 2:9, REV 3:9 - If you were kicked out of 109 bars, would you think the problem was you, or the 109 bars?
MSattler is offline  
post #5 of 5 (permalink) Old 05-21-2020, 11:30 AM
Super Moderator
 
Join Date: Feb 2013
Location: SW Florida
Posts: 2,526
iTrader: (5)
 
Quote:
Originally Posted by MSattler View Post
1 or 2 hp? That's essentially a difference in humidity.
and not even a large change in humidity
Spockster and MSattler like this.

2005 VN750

Sold 11-27-17
michiganteddybear is online now  
Sponsored Links
Advertisement
 
Reply

Bookmarks

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Kawasaki Vulcan 750 Forum : Kawasaki VN750 Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

Once registered, your User Name"cannot be changed". We can make exceptions within 7 days, but after that, it is set in stone.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome