turbo vs. non turbo heads
02-17-2009, 06:53 AM
#16
XRC test are good. Turbo plugs absolutely can increase peak power and broaden that peak curve. It can be measured with the right equipment. 
If everything was the same, Head Volume, Squish Width, Squish Angle, Head Clearance, etc... so that your Static Compression Ratios are identical. Without a doubt the turbo plug has the potential to out perform the standard plug. Not considering transition between head and plug, but just how the plug seals alone offers that extra effective cylinder pressure to make more power.
Turbo plugs seal at the base of the plug or top of the combustion chamber. Standard plugs seal on the top of the head button, outside of the combustion chamber. So when in a dynamic state, the effective compression is lost with any leakage around the threads. What this does is increases the head volume reducing the effective compression ratio, and reducing your BMEP. ( Average Cylinder Pressure)
Sometimes running standard plug engines I will drop the head .002" to help.
Hope this helps.
Ed
If everything was the same, Head Volume, Squish Width, Squish Angle, Head Clearance, etc... so that your Static Compression Ratios are identical. Without a doubt the turbo plug has the potential to out perform the standard plug. Not considering transition between head and plug, but just how the plug seals alone offers that extra effective cylinder pressure to make more power.
Turbo plugs seal at the base of the plug or top of the combustion chamber. Standard plugs seal on the top of the head button, outside of the combustion chamber. So when in a dynamic state, the effective compression is lost with any leakage around the threads. What this does is increases the head volume reducing the effective compression ratio, and reducing your BMEP. ( Average Cylinder Pressure)
Sometimes running standard plug engines I will drop the head .002" to help.
Hope this helps.
Ed
02-17-2009, 07:07 AM
#17
XRC test are good. Turbo plugs absolutely can increase peak power and broaden that peak curve. It can be measured with the right equipment.
If everything was the same, Head Volume, Squish Width, Squish Angle, Head Clearance, etc... so that your Static Compression Ratios are identical. Without a doubt the turbo plug has the potential to out perform the standard plug. Not considering transition between head and plug, but just how the plug seals alone offers that extra effective cylinder pressure to make more power.
Turbo plugs seal at the base of the plug or top of the combustion chamber. Standard plugs seal on the top of the head button, outside of the combustion chamber. So when in a dynamic state, the effective compression is lost with any leakage around the threads. What this does is increases the head volume reducing the effective compression ratio, and reducing your BMEP. ( Average Cylinder Pressure)
Sometimes running standard plug engines I will drop the head .002" to help.
Hope this helps.
Ed
If everything was the same, Head Volume, Squish Width, Squish Angle, Head Clearance, etc... so that your Static Compression Ratios are identical. Without a doubt the turbo plug has the potential to out perform the standard plug. Not considering transition between head and plug, but just how the plug seals alone offers that extra effective cylinder pressure to make more power.
Turbo plugs seal at the base of the plug or top of the combustion chamber. Standard plugs seal on the top of the head button, outside of the combustion chamber. So when in a dynamic state, the effective compression is lost with any leakage around the threads. What this does is increases the head volume reducing the effective compression ratio, and reducing your BMEP. ( Average Cylinder Pressure)
Sometimes running standard plug engines I will drop the head .002" to help.
Hope this helps.
Ed
Does anyone else feel as dumb as me?
ED dude I only understand faster or not faster...lol
What are your findings on the EBM5 over the stock Go 5 port?
02-17-2009, 08:20 AM
#18
Thanks for all the good info I am tring to decide wether to buy a turbo button for my fantom fr27. I thought it was a turbo button but it was not so I am going to buy the button but I wanted to know what the real world differences where between the two.
02-17-2009, 08:47 AM
#19
02-17-2009, 09:17 AM
#21
XRC test are good. Turbo plugs absolutely can increase peak power and broaden that peak curve. It can be measured with the right equipment.
If everything was the same, Head Volume, Squish Width, Squish Angle, Head Clearance, etc... so that your Static Compression Ratios are identical. Without a doubt the turbo plug has the potential to out perform the standard plug. Not considering transition between head and plug, but just how the plug seals alone offers that extra effective cylinder pressure to make more power.
Turbo plugs seal at the base of the plug or top of the combustion chamber. Standard plugs seal on the top of the head button, outside of the combustion chamber. So when in a dynamic state, the effective compression is lost with any leakage around the threads. What this does is increases the head volume reducing the effective compression ratio, and reducing your BMEP. ( Average Cylinder Pressure)
Sometimes running standard plug engines I will drop the head .002" to help.
Hope this helps.
Ed
If everything was the same, Head Volume, Squish Width, Squish Angle, Head Clearance, etc... so that your Static Compression Ratios are identical. Without a doubt the turbo plug has the potential to out perform the standard plug. Not considering transition between head and plug, but just how the plug seals alone offers that extra effective cylinder pressure to make more power.
Turbo plugs seal at the base of the plug or top of the combustion chamber. Standard plugs seal on the top of the head button, outside of the combustion chamber. So when in a dynamic state, the effective compression is lost with any leakage around the threads. What this does is increases the head volume reducing the effective compression ratio, and reducing your BMEP. ( Average Cylinder Pressure)
Sometimes running standard plug engines I will drop the head .002" to help.
Hope this helps.
Ed
Just to add, make sure if you do use a turbo head/plug, you clean the area of dirt before removing and installing the glowplug. A lot of people will get dirt into the taper area and comprimise the sealing taper. This is not good. Also using the incorrect glowplug with a different taper may also cause sealing issues too. If you don't do this, then don't bother with a turbo head button/plug.
02-17-2009, 11:12 AM
#22
The biggest difference I have noticed once I switched was that Turbo plugs are twice the price, but last 4 times longer..I do not notice the engine to be any smoother, or more powerful, my top and bottom are about the same, my fuel consumption has not changed much...It is really nice to go up to 2 gallons of fuel on the same plug..and not have to fumble around to change one at the track, with your cooling head all full of dirt.
so it could of gone longer, it is on his second plug and its about 1.5 gallons and runnin strong
02-17-2009, 12:39 PM
#23
I ran the stock plug that came in my v-spec for 5 gallons!! 5 GALLONS!!! Including break-in. no standard plug would last that long. I just changed it at the crcrc nitro champs because I thought is would be a good Idea. It still glows fine and is in my pit box still. Crazy. For me, someone who never had a turbo engine until the v-spec, it really surprized me.
02-17-2009, 05:52 PM
#24
XRC test are good. Turbo plugs absolutely can increase peak power and broaden that peak curve. It can be measured with the right equipment.
If everything was the same, Head Volume, Squish Width, Squish Angle, Head Clearance, etc... so that your Static Compression Ratios are identical. Without a doubt the turbo plug has the potential to out perform the standard plug. Not considering transition between head and plug, but just how the plug seals alone offers that extra effective cylinder pressure to make more power.
Turbo plugs seal at the base of the plug or top of the combustion chamber. Standard plugs seal on the top of the head button, outside of the combustion chamber. So when in a dynamic state, the effective compression is lost with any leakage around the threads. What this does is increases the head volume reducing the effective compression ratio, and reducing your BMEP. ( Average Cylinder Pressure)
Sometimes running standard plug engines I will drop the head .002" to help.
Hope this helps.
Ed
If everything was the same, Head Volume, Squish Width, Squish Angle, Head Clearance, etc... so that your Static Compression Ratios are identical. Without a doubt the turbo plug has the potential to out perform the standard plug. Not considering transition between head and plug, but just how the plug seals alone offers that extra effective cylinder pressure to make more power.
Turbo plugs seal at the base of the plug or top of the combustion chamber. Standard plugs seal on the top of the head button, outside of the combustion chamber. So when in a dynamic state, the effective compression is lost with any leakage around the threads. What this does is increases the head volume reducing the effective compression ratio, and reducing your BMEP. ( Average Cylinder Pressure)
Sometimes running standard plug engines I will drop the head .002" to help.
Hope this helps.
Ed
02-17-2009, 08:14 PM
#25
I guess i will chime in and explain what Ed started to:
Brake Mean Effective Pressure is the average mean pressure which, if imposed on the pistons uniformly from the top to the bottom of each power stroke, would produce the measured brake power output. The equation for figuring out BMEP is:
BMEP= IMEP-FMEP-PMEP
The simplest explanation without confusing everyone is BMEP is the overall cranking compression. Compresson ratios can be figured out a number of ways, some engine builders use Swept volume (Total Cylinder Displacement) divided by Head Volume (Installed cc), some use the BMEP. The thing about BMEP is that because it totally relies on effective pressure, the reading will be different from engine to engine ie:
Comparing a brand new engine to a 4 gallon identical engine. The new engine will always read higher because the piston to wall clearances are tighter allowing less blow by which will indicate higher cylinder pressure. What Ed is saying, because the seal of the standard plug is at the copper washer and the turbo plug is at the base of the plug, the turbo plug will have a higher BMEP acting as if the engine has a higher compression ratio thus giving the engine more "pop" as some call it resulting in a faster burn giving the engine the feel of more torque. the thing you have to understand about engines is that there is a hell of alot more to them then BMEP. There is Indicated Mean Effective Pressure(Overall Pressure), Friction Mean Effective Pressure(Rotational losses from bearings, rod, piston etc.), Pumping Mean Effective Pressure(Vacuume created during power sroke), Piston Speed(Feet per second), Rotational Mass, Elavation, Barometric Pressure, Humidity etc.
Basically the BMEP can only be used as a guideline and will not be the same from engine to engine as every engine has different load bearing, friction loss and vacuume pressure that will affect usable torque. If you take 1 engine and switch between a standard plug and a turbo plug, provided the installed cc's are identical, the plug heat range is identical and the BMEP is identical, you should not see a difference in performance between the two because to put it simple, if all of the above is identical (in the perfect world) the mixture does not know the difference between a standard plug filiment and a turbo filiment. All you need is a candle to light the fire and all the other forces mentioned above take care of the rest.
This is why you have all sorts of opinions on the subject because most of them have put together different combinations of plugs, on different aged engines, on different brand engines, compression ratios, pipes used etc. and all have had different results.
I hope this explains a little more for you guys
Brake Mean Effective Pressure is the average mean pressure which, if imposed on the pistons uniformly from the top to the bottom of each power stroke, would produce the measured brake power output. The equation for figuring out BMEP is:
BMEP= IMEP-FMEP-PMEP
The simplest explanation without confusing everyone is BMEP is the overall cranking compression. Compresson ratios can be figured out a number of ways, some engine builders use Swept volume (Total Cylinder Displacement) divided by Head Volume (Installed cc), some use the BMEP. The thing about BMEP is that because it totally relies on effective pressure, the reading will be different from engine to engine ie:
Comparing a brand new engine to a 4 gallon identical engine. The new engine will always read higher because the piston to wall clearances are tighter allowing less blow by which will indicate higher cylinder pressure. What Ed is saying, because the seal of the standard plug is at the copper washer and the turbo plug is at the base of the plug, the turbo plug will have a higher BMEP acting as if the engine has a higher compression ratio thus giving the engine more "pop" as some call it resulting in a faster burn giving the engine the feel of more torque. the thing you have to understand about engines is that there is a hell of alot more to them then BMEP. There is Indicated Mean Effective Pressure(Overall Pressure), Friction Mean Effective Pressure(Rotational losses from bearings, rod, piston etc.), Pumping Mean Effective Pressure(Vacuume created during power sroke), Piston Speed(Feet per second), Rotational Mass, Elavation, Barometric Pressure, Humidity etc.
Basically the BMEP can only be used as a guideline and will not be the same from engine to engine as every engine has different load bearing, friction loss and vacuume pressure that will affect usable torque. If you take 1 engine and switch between a standard plug and a turbo plug, provided the installed cc's are identical, the plug heat range is identical and the BMEP is identical, you should not see a difference in performance between the two because to put it simple, if all of the above is identical (in the perfect world) the mixture does not know the difference between a standard plug filiment and a turbo filiment. All you need is a candle to light the fire and all the other forces mentioned above take care of the rest.
This is why you have all sorts of opinions on the subject because most of them have put together different combinations of plugs, on different aged engines, on different brand engines, compression ratios, pipes used etc. and all have had different results.
I hope this explains a little more for you guys
02-18-2009, 05:58 AM
#26
My comment here may be steering the tread away from the TURBO question, but in addition to the TURBO style heads, there are heads with single bubble, double bubble, off-set bubble ... and the list goes on. The ultimate goal is to maximize turbulance w/in the bubble for maximum burn. There are many other factors associated with the gas flow through the combustion chamber, that if the whrong style head is introduced to the equation, the engine will never run like it should/could.
This could become an interesting thred
This could become an interesting thred
02-18-2009, 06:34 AM
#27
all I know is on any Picco there is a noticeable difference between the performance of the standard head and the turbo head...It may be due to differences in head button design, or the better sealing...but running turbo and standard back to back on the same engine you can feel clear as day the turbo button is stronger and snappier.. If you run a Picco your losing out not running a turbo
02-18-2009, 07:39 AM
#28
Chamber design can absolutely affect the outcome. Piston crown design can affect it and putting the wrong combinations together can have a negative impact on engine performance. Depending on the squish band length, angle and depth, alot of things can happen. Most of the time engines like to have a +1 degree rake from the cylinder wall into the chamber area. This angle depends on the piston crown design. Lets say you have a piston with a 10 degree rake from crown edge to center. You typically want the squish to be 10.5 to 12 degrees giving the compressing gasses a pathway into the chamber area as the piston approaches TDC. If you use a negative rake in the squish band, some of the charge starts the ignition process along the edges of the piston causing preignition situations resulting in pitting and could result in premature engine failure. There is also a rule of thumb and that is, you want the squish band to be approximately 33% of the pistons radius. If its too small, the loop scavaging process isn't working to it's full potential and if it's too big, preignition is usually the end result.
Another thing to consider is dome design. A dome design in more of a flat top design where the charge is directed more towards the center of the piston tends to have longer power stroke energy as opposed to a dome directing the charge towards the pistons edge which in turn bounces of the wall losing energy thus the power stroke is shortened and tends to be weaker reducing torque and power output.
Compression ratio is also another factor as well and depending on what that is will depend on the fuel you will be able to run, what EGT(exhaust gas temperature) will be, how accelerated the burn is and what overall temp will be and depending on how efficient the engine can disappate heat, will depend on the average head temp and depending on the temperature gun you use will depend on what that number will be. That's why I always say to use the temp gun as a baseline for you and only you because your engine will always read different than someone elses. If you think the engine is running good and the temp stabalizes in a decent range, then chances are it's good to go.
I'm sure there will be a number of different opinions and ways people reach a similar answer but these are just my findings over years of engine design and everyone has a different way to get the answer that works for them so take this as only my method and some will agree and some will disagree.
Another thing to consider is dome design. A dome design in more of a flat top design where the charge is directed more towards the center of the piston tends to have longer power stroke energy as opposed to a dome directing the charge towards the pistons edge which in turn bounces of the wall losing energy thus the power stroke is shortened and tends to be weaker reducing torque and power output.
Compression ratio is also another factor as well and depending on what that is will depend on the fuel you will be able to run, what EGT(exhaust gas temperature) will be, how accelerated the burn is and what overall temp will be and depending on how efficient the engine can disappate heat, will depend on the average head temp and depending on the temperature gun you use will depend on what that number will be. That's why I always say to use the temp gun as a baseline for you and only you because your engine will always read different than someone elses. If you think the engine is running good and the temp stabalizes in a decent range, then chances are it's good to go.
I'm sure there will be a number of different opinions and ways people reach a similar answer but these are just my findings over years of engine design and everyone has a different way to get the answer that works for them so take this as only my method and some will agree and some will disagree.
02-18-2009, 10:36 AM
#29
For me the jury's still out on the amount (if any) taper to use on the squishband for a car engine. On my car engines I'm setting my head clearances around .018", on my marine engines I run my clearance down to .006". 
My experience is leaning me toward the belief that low nitro with the >.020" head clearances likes a more tapered squishband and < .010" high nitro (like my marie engines) likes a flatter squish band. I agree squishband area is very important to get the fuel to burn. The squish band does a couple things 1. it reduces the area in which combustion occurs, accelerating the rate of combustion (not the timing) 2. the squishband of the head acts as a heatsink and cools the edge gases to help control detination. Your 33% is close to my number, I tend to like the squishband area to be equal to 60% of the pistion face area.
My experience is leaning me toward the belief that low nitro with the >.020" head clearances likes a more tapered squishband and < .010" high nitro (like my marie engines) likes a flatter squish band. I agree squishband area is very important to get the fuel to burn. The squish band does a couple things 1. it reduces the area in which combustion occurs, accelerating the rate of combustion (not the timing) 2. the squishband of the head acts as a heatsink and cools the edge gases to help control detination. Your 33% is close to my number, I tend to like the squishband area to be equal to 60% of the pistion face area.
02-18-2009, 05:40 PM
#30
Wow, there's a lot of technical info coming out here! I'm learning