powre lynz question
 

been researching threading the intakes on heads, called powre lynz ,since the powre lynz promote a more complete burn, is it a faster burn, or a slower burn? I believe with a faster burn you would want to retard timing, and with a slower burn, you would want to advance timing ? since my motorcycle has round intakes, I used a 3/4 " pipe tap to thread the manifold just before it enters the head. if all goes well, I will thread the intake ports on the head. started with the manifolds because I am afraid of ruining the heads! any info would be greatly appreciated.

Just be careful doing like that that you don't force the tap in and crack the head.

As I understand the power lynz concept, it just helps the fuel to mix more completely with the air..

I would guess that if the lynz do anything at all, they would slightly accelerate the combustion process, as Singh grooves are supposed to do.

If you have the head off the engine it might be worth checking out Singh grooves as well.

https://www.somender-singh.com/

There's several effects they have...

i) "fixing" intake and manifold shape. When there are shape changes that might cause large blocking vortices to form, they preempt the formation of large vortices by causing a more controlled laminar to turbulent flow transition, provoking flow breakdown into smaller vortices. Think of this as trying to push golfballs down a convoluted tube vs pouring small BBs down it.

ii) Variable boundary layer effect. Mpgmike has done some flow tests that suggests that at lower air speeds, the boundary layer is thickened, while allowing the boundary layer to compress at higher intake air speeds. This appears to be equivalent to having variable sized intake tubing, keeping torque high at the low end. The core of the air column entering the engine will be kept at high speed, by the virtual narrowing of the the intake, and thus having higher momentum, makes for better torque. Entering the chamber at higher speeds it will promote even mixture distribution and make for better swirl and tumble.

iii) In a carburated or TBI induction system, the outer edge turbulence keeps fuel suspended better, and while the bulk velocity of the mixture may be low, the local velocitys and accelerations work to mix the fuel and air better and help it evaporate into the intake air, possibly helping break up larger droplets in mid flow.

iv) In a multipoint fuel injection system, the injectors at low demand, in approx 90% of normal driving, are actually spraying against a closed valve. This means that the ports are wetted down with fuel, which will hopefully evaporate off the warm port walls... lynz will have a wicking effect, due to capillary action and surface tension, that will spread the fuel out, lessening puddling effects and "cool spots" in the port due to fuel collecting there. This along with increased surface area maximises the transfer of intake port heat to the fuel, allowing efficient vaporisation before the valve opens.

RoadWarriors proposed modifications to lynzing strategy and port treatments...

Variable textures, or directed texture application. While coarser lynz will help better for flow discontinuity fixing, finer lynz will work better for fuel wicking in MPFI motors. Therefore ideally, coarser textures should be used just before shape changes, and finer textures in flatter/smoother areas. TBI and carbed motors should be wetting the walls relatively less than MPFI though, so this may not make a difference on those.

Shape of lynz. Aiming for a sawtooth shape that leans in the direction of flow, with a right angled back edge may discourage reversion. i.e.
|\|\|\|\ <=
vs
/\/\/\/\ <=
By making resistance to flow in reverse direction higher.

Ultrasonic droplet cracking enhancement... although the lynz may in places have an effect similar to this, by accident really, setting out to make ultrasonic noise may be beneficial. Meaning that while some lynz work may have significant ultrasonic activity, some may barely have any. It's claimed by several gizmo manufacturers that ultrasonic transducers will cause resonance in fuel droplets, causing them to break up into finer droplets. Since these gizmos will be fixed frequency like as not, then there's only one specific size of droplets, or narrow range they will work on... can we do better? Possibly... Using the helmholtz resonator principle (think of blowing over a beer bottle) it appears that small resonance cavities in areas of high flow would produce ultrasonic noise. I calculated that the approximate size necessary is 1-2mm deep pits, drilled with a 1/16 bit. These should, drilled in a range of depths between 1 and 2 mm produce a range of frequencies between 30 and 60Khz. These should be placed in areas of high airflow, near to where the fuel is introduced. i.e. in the intake right above the injectors for example, or maybe in the throttle body if carb or TBI. (If you have one of those split intakes, I guess you could do them in the middle too) These would have best effect in areas where flow is likely to be laminar, and high speed, outside radiuses for example.

Additional port treatments..(Experimental) I have come to believe that in an MPFI engine where the ports are wetted significantly, it may be beneficial to copper plate them (after lynzing) this is because ethanol may be catalytically cracked at temperatures starting around 70C by copper, into hydrogen and ethyl acetate, and acetone like ketones... These may have combustion promotion effects more favorable than that of ethanol. In a TBI or carbed motor, achieving this may be more difficult, since the port is not expected to be wetted to the degree that an MPFI port is, and passing the mixture over a heated copper catalyst would entail flow restriction. With E10 fuel at highway speeds in a warmed up engine with a 195* thermostat, it appears that as much H2 would be produced as in some HHO cell setups... it's potentially possible that a motor thus converted with the hottest thermostat available would run very well on E85 and get better mileage than on E10 or straight gas.... I'll see about that if I ever find E85 up here after I've done this to my Escort. Fuel heaters or warm air intakes would further promote this effect. I plan to copper plate the back of the intake valves also.

Anyway, work in as much of that as you want/need or believe in.

Road Warrior

thanks for the info, you have given me a lot to chew on. the heads are still on the motorcycle, and the 3/4 tap fits prefectly. the manifolds tapped very easily, hoping the heads will too.planning on stuffing tissues into intakes, tapping, and using vacuum to clean them out. they are aluminum heads, and should tap easily.

I put threads in my intakes and it was as easy as I had hoped. haven't had a chance to check mileage yet, but am still wondering if the fuel will burn faster, and if so, should I retard the timing ?

I've got my bike completely pulled apart and am thinking about doing the same thing... Im anxious awaiting your results

it turned wet here so I haven't had a chance to test the results, initial test ride didn't show any problems, and power changes are hard to feel on a 100 h.p. motorcycle, however, I am more interested in seeing a mileage gain . will post my results when the weather changes.

1st tank since doing powerlynz and retarding ignition to stop pinging was 45 mpg. that was with out trying to drive careful so those numbers aren't bad this bike has 6 carbs, so how hard you drive makes a big difference , alot of riders out there average in the low 30s, might try advancing cams to see if that helps

Sounds promising, do you have any numbers from the same bike to compare to before the threads?

I still have some time before the motor goes back in to do these, though my runners arent perfectly round so it looks like I'll have to do it with a grinder

What I'm planning to lynz with is sections of coarse "barsteward"* round file, chucked into a drill. You might also be able to use a tap turning in a drill, one of the larger sizes (smaller than your port) with 5 or 6 slots down it would probably work better than one of the smaller ones with 4, since the edges won't catch so much when it's spinning. I'm going to be using the file though to try to get the antireversion |\|\|\ profile to them.

(*Thought the right word would trip the filter)

I have gotten as low as 40 mpg, depending on driving conditions. the weather has been cool, and this last tank was a combination of several short trips around town, and several 20 mile trips in the mountains. I am also running a couple of degrees retarded on timing due to a pinging problem I have had for some time. I am running ngk plugs with a hole drilled for better spark and am wondering if the sharp edges on the plug could be causing the problem. as far as the lynz mod,the bike seems to have good power, even with retarded timing, so I would say at the very least, they didn't hurt anything, and I would recommend giving them a try

in an aluminum head, it was pretty easy to tap them by hand. even if they are not perfectly round, a tap might still work. I would hesitate to use a drill, things could get out of hand if not careful

The plug mod might also be lighting the mixture off sooner, if it's throwing spark right out into the chamber instead of setting off a fizzle. Timing should be set for peak cylinder pressure at the right point, if that means retarding it, do it, it doesn't mean losing power.

I'm meaning a tap smaller than the port used like a burr.

I understand the advantage of getting the spark closer to tdc, and agree that pinging costs power and mileage. most people equate advancing the spark for more power and mileage, but retarding the spark can help you get over the wall, rather than running you into the wall. I never considered the plugs firing the mixture sooner, but that makes sense. I had to modify the trigger wheel to retard the timing since they only make wheels with more advance. thanks again for the info

IF it's got plenty of advance to play with, you could try lifting the dizzy, slipping it back by a tooth, and "advancing" to where you need to be. Stock from the factory, most vehicles are set up with conservative advance, so it won't ping on crappy gas. Hence peak cylinder pressure is some time after TDC and hence the "more advance = more power" thinking. With any vaporisation, ignition and mixture improvements, we might expect earlier peak pressure.

no dizzy, this is a 6 cyl. motorcycle with 6 coils, makes timing changes a little more time consuming, but not impossible, just modify the trigger wheel