Turbo plugs discussion
10-04-2012, 09:15 PM
#1
Turbo plugs discussion
There was some discussion on some other threads about tapers being different between brands. I had done some measuring over 5 years ago but decided to do some more measuring and report what I found.
I used an optical comparator to measure tapers and width accross the bottom.
Here is the dimensions I found on these plugs, all seem to be 60 degrees with a 3/16 or .187 bottom dia. The differences between plugs is probably just more of a difference in manufacturing tolerance than difference between brands. These are not ground so you will see some difference in the same brand.
Now I am not saying every brand plug will work in every motor. Os for example does not tap the thread as deep as others in the head button down to the taper. You will notice the Os has what appears to be a shorter taper. It has a smaller dia. between the taper and thread for clearance. So if you try a Nova plug in a Os the threads may bottom out before the taper seals.
I have also heard of problems using a Os plug in a Nova motor and some other brands. I feel that if the Os plug is overtightened it may smash the taper in the head into the chamber some. This is because it has a slightly shorter taper so the force is put on a smaller area.
Rex
I used an optical comparator to measure tapers and width accross the bottom.
Here is the dimensions I found on these plugs, all seem to be 60 degrees with a 3/16 or .187 bottom dia. The differences between plugs is probably just more of a difference in manufacturing tolerance than difference between brands. These are not ground so you will see some difference in the same brand.
Now I am not saying every brand plug will work in every motor. Os for example does not tap the thread as deep as others in the head button down to the taper. You will notice the Os has what appears to be a shorter taper. It has a smaller dia. between the taper and thread for clearance. So if you try a Nova plug in a Os the threads may bottom out before the taper seals.
I have also heard of problems using a Os plug in a Nova motor and some other brands. I feel that if the Os plug is overtightened it may smash the taper in the head into the chamber some. This is because it has a slightly shorter taper so the force is put on a smaller area.
Rex
10-04-2012, 10:53 PM
#2
There was some discussion on some other threads about tapers being different between brands. I had done some measuring over 5 years ago but decided to do some more measuring and report what I found.
I used an optical comparator to measure tapers and width accross the bottom.
Here is the dimensions I found on these plugs, all seem to be 60 degrees with a 3/16 or .187 bottom dia. The differences between plugs is probably just more of a difference in manufacturing tolerance than difference between brands. These are not ground so you will see some difference in the same brand.
Now I am not saying every brand plug will work in every motor. Os for example does not tap the thread as deep as others in the head button down to the taper. You will notice the Os has what appears to be a shorter taper. It has a smaller dia. between the taper and thread for clearance. So if you try a Nova plug in a Os the threads may bottom out before the taper seals.
I have also heard of problems using a Os plug in a Nova motor and some other brands. I feel that if the Os plug is overtightened it may smash the taper in the head into the chamber some. This is because it has a slightly shorter taper so the force is put on a smaller area.
Rex
I used an optical comparator to measure tapers and width accross the bottom.
Here is the dimensions I found on these plugs, all seem to be 60 degrees with a 3/16 or .187 bottom dia. The differences between plugs is probably just more of a difference in manufacturing tolerance than difference between brands. These are not ground so you will see some difference in the same brand.
Now I am not saying every brand plug will work in every motor. Os for example does not tap the thread as deep as others in the head button down to the taper. You will notice the Os has what appears to be a shorter taper. It has a smaller dia. between the taper and thread for clearance. So if you try a Nova plug in a Os the threads may bottom out before the taper seals.
I have also heard of problems using a Os plug in a Nova motor and some other brands. I feel that if the Os plug is overtightened it may smash the taper in the head into the chamber some. This is because it has a slightly shorter taper so the force is put on a smaller area.
Rex
60° +/- was known beforehand but great job confirming Rex
highlighted area above is what i was trying to get across to guys for a long time
conclusion: i wouldnt recommend ,nor would any faithful novarossi user, to thread os plugs in your novarossi unless you never plan on switching back to odonnell or novarossi plugs
your
10-04-2012, 11:00 PM
#3
Great info and it makes complete sense Thanks for posting that's a cool instrument
10-05-2012, 04:52 AM
#5
The OS and Voodo look very simular. I am suprized to see how shallow the angle is on the OD plug campared to the rest. That's a 20* differnce to the rest.
10-05-2012, 05:26 AM
#6
10-05-2012, 05:43 AM
#7
IMO the length of the taper has little value..the real thing is the angle...if the angle and width is the same the plugs are going to seat properly.... so IMO a OS plug has just as much chance of damaging a OS button from over tightening as it does a Nova button !
Last edited by Maximo; 10-05-2012 at 06:03 AM.
10-05-2012, 07:32 AM
#8
10-05-2012, 07:58 AM
#10
Over the last 20 years I have run every brand plug in every brand engine and never had any problems with sealing let alone any other issues. And that is with switching back and forth from brand to brand to whatever the local shops had in stock back then.
10-05-2012, 09:43 AM
#12
+1, i have also used OS plugs, OD plugs, voodoo, nova, werks, in my novarossi, ninja, OS, werks engines with no issues at all.
10-05-2012, 01:34 PM
#13
I have never had any problems switching from different brand plugs. I ran quite a few of the Voodoo plugs a couple years ago, they are relieved similar to the Os.
I am sure with the amount of motors Monty works on he has seen a few messed up head buttons. Maybe the Nova head buttons are the problem? Just kidding, I have ran Nova's in the past with no issues, my favorite was the 421b!
Rex
I am sure with the amount of motors Monty works on he has seen a few messed up head buttons. Maybe the Nova head buttons are the problem?
Just kidding, I have ran Nova's in the past with no issues, my favorite was the 421b!Rex
10-05-2012, 03:18 PM
#14
Debates are cool 
as long as they are respectful and people dont get bent. The moral of the story is run what you want and enjoy your micro engine even if its spurting fuel out of the button > Joke 
as long as they are respectful and people dont get bent. The moral of the story is run what you want and enjoy your micro engine even if its spurting fuel out of the button > Joke