Jump to content
IGNORED

another 3 cylinder beast


Patch

Recommended Posts

I've been following free valve technology for a while, interestingly they believe its sole market will be performance oriented only; but just look at what it can do...

 

If you remember this guy started posting pretty young. Posted just this march 18th

 

Link to comment
Share on other sites

We had a F 150 in the shop from our local Ford dealer a couple weeks back. I had some small azz 2.5 or something in it. Really? I had an Escort wagon with a motor almost that big. But if your just gettin groceries I guess its OK.

Link to comment
Share on other sites

The smallest F150 engine is the 2.7L V6 ecoboost. 0 to 60mph I think it is the quickest of all the F150s, even quicker than the 3.5 eco to 60mph. From what I've been reading the ecoboost engines are fairly reliable. The 3.5 eco has been on the market now for 10 years. The Mustang hotrodders have been testing the limits of the 2.3L 4 cyl ecoboost and it's supposed to be a good engine. It's the only engine option for the new Ranger. I'm old school though and I'm still hanging on to my 2002 F150 with the 5.4L 2 valve V8 that is a very reliable engine. One of those in a van lasted 1,299,000 miles before it blew. Google Million Mile Ford Van to read about it.

Link to comment
Share on other sites

Interesting. Not much of a gearhead but how can this engine be applied to bikes? We already have Big Bore V-Twins. How can this translate to 2 Cylinders vs 3 and would that even work. I get the exhaust limiters and turbo chargers. I'm a little miffed on the variable valves benefit to a bike though?

Link to comment
Share on other sites

With the piston speed equal to a Formula 1 race car engine, it would cost way too much to build it, so not much chance of it being put into any vehicle that consumers buy any time soon. Remember those Honda race bikes that would rev to about 23,000 rpm?

Link to comment
Share on other sites

Interesting. Not much of a gearhead but how can this engine be applied to bikes?

We already have Big Bore V-Twins.

How can this translate to 2 Cylinders vs 3 and would that even work.

I get the exhaust limiters and turbo chargers.

I'm a little miffed on the variable valves benefit to a bike though?

 

For the first 2 questions, this gets to the heart of crank timing, or crank plain, (i'll skip that) when you have odd numbers you choose when the trailing stroke will produce its contribution so that means you have a boost to crank rotation, because it is rotating then it falls under torque! This is why we measure such ins and outs from the centers of.... If you revisit the video I posted about differentials this is explained as they fill in the gears.

 

The next 2 questions are very technical to answer; the engine heads are where the power decisions meet Mama Compromise;)

As you've read in other stuff I've written it is always about the air or induction first. If you have a great plan for the heads then you build the bottom/crank to accept the potentials,,, when you build from scratch!

When we can alter valve timing we can tune efficiencies through the entire RPM range, so biggest bang for duration and there's multiple duration's to consider.

There are also losses that we have had to accept; we know this because the math tells us we have losses. The valves are under continuous kinetic pressure which the strokes has to overcome twice per, per set of valves, per cylinder... There we use lever actions from the crank up through the chain, lobes and so on, that means weight, friction and energy losses,

(nothing for nothing) So that to a great deal is reduced so we have a freer revving engine; yes we still have to drive the valve system but...

 

For bike applications well not yet, even if we can manage the engine we would still have losses transferring the output!

 

Yes I remember Sky Honda often comes up with surprises to cause us to wonder;)

 

I'll give you all one more thing to think on, exhaust ports have a lot of wasted energy when you consider we mostly just dump it; often too in the wrong size piping.

Link to comment
Share on other sites

Remember 85 and 86 when Bill Elliot's Ford Thunderbird was a sure winner on the high speed Nascar tracks. At one of the high speed tracks, he lost a tire and made up the 2 (2 1/2 mile) lap loss under the green flag. Some guy in Texas had come up with heads for his engine that had a swirl type combustion chamber that could be used with compression ratios up to 18 to 1 and it extracted more power from combustion and the exhaust gas was much cooler than normal. GM jumped on the bandwagon with new "vortec" heads for their cars. This is when he set the all time track record of 212mph at Talladega. Not long after Nascar limited compression ratios to 12 to 1 and used restrictor plates to reduce speeds. Nascar also disallowed Ford engines built on the Cleveland engine block forcing engine builders to use engines built on the Windsor block. This curtailed the room for building high flow heads since the Windsor engine was a small block and the Cleveland was more of a big block engine.

 

Passenger cars are not allowed to run too high compression ratios because it increases Nitrogen oxides, a pollutant.

Link to comment
Share on other sites

Some history, lol my mom figured I had something goin on in my head as a boy around engines, any kind didn't matter!

In the 60's she would tune the antenna Saturday afternoon so I could watch USA racing, AJ Foyt was my favorite! Anyway she pops in the living room with snacks and one afternoon and asks me how the race was... OH Mom when I become a dad I am going to call my boy AJ, lol. Some decades later My wife says ok well how will be spell it? Hmm like I'd know, so we settled on AJay, true story.

She order some paperback books for me, smallish books it was a series they drew pics of aerodynamics with simplified explanations. And tho it took a long while to understand the theories that seeded my fascination with those dynamics.

 

Yes I remember all the way back to the 70s swirl add on's. For myself it took some trial and errors of course like grinding in swirls funny really looking back. Now as I remember the GM Vortex was 96??? But my old 86 Cade has swirl heads.

So what is it? Well its a chase really and not consistent either, the velocity is important but the pressure distort it, all at very high sequencing I might add. If you have ever managed to see cylinder induction then you know there is a lot of turbulence; you also can't help but notice the air/fuel crash on the crown, which depending on crown shape and speed the rush to the walls can be obvious..

This is super important as the next stop is the combustion chamber and its design can split the ignition (more so in the pre mid 80's) Now you factor in Ignition (we rather not but we need it) advance which is all about duration, compression heat, and effective spark,,,,,,,,,,,,,,,,,,,,, This is where it get tricky I'll wind it up here, lets take a quick look at gen1's intake valves open, that's 2 bell shapes air/fuel rushes past @ 5 pounds vacuum, piston travelling down: as it reaches BDC the piston stops producing low pressue; as the air flows past the 2 bell shapes side by side they cause a swirl that swirl also slows the movement of the flow, as does the wall surface, mixing stops, but there was also a swirl created in and upward movement during the crash with the crown! The chamber environment is very hot causing the charge to begin to expand! WOOPS remember the BDC & TDC have 2 things in common one is they both cause the direction to reverse and the other is the connecting rod is in a straight line with the crank at their longest point! So that a loss which gets put into the lose locum: so the compression stroke is fed from the firing order and it has to overcome the next inline to compress the expanding gasses even before the ignition timing lights the charge! BUT now in the process of charge ignition and expansion the now flaming charge is tumbling, yup! So what if we could alter the these sequences? Well we can and in so doing our efficiency goes up and when rpm are down low we see that in torque; up high we measure it in HP gains but, they are only a fraction of what they should be because we find that measure up in the high bands where we know our filling duration's run lower efficiencies, now if we can alter that by changing valve duration and retard the ignition timing to reduce expansion pressure @ less efficient crank angles,,,,,,, because we kept the filling duration up (which heat will expand) then we develop more much much higher numbers.

So duration's and ignition timing the ignition side is easy, sequential firing can get that done for us;)

 

Hope its English and hope it helps fill in some of the shadows

Edited by Patch
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...