V10 idea:

[jediali]

I don't understand what you mean really..?
can you explaine how you see this exhaust works good with un-equal lengths?
Just qurious to find out

i dont see why some exhaust deisgn is so strict. My idea of high performance.

exhaust valve opens creating compressive pressure wave due to pressure difference in exhaust gas flow. this shock wave travels to next branch downstream. at this branch a ...
...compressive pressure wave is sent downstream
...expansion pressure wave is sent back upstream to various cylinders

the expansion waves are designed to arrive at each cylinder just as the exhaust valves are opening thus creating a vacuum to encourage cylinder emptying and indicated efficiency.

This is tricky to achieve but just requires some basic mach index equations, but its lead me to this so far. the V10 firing order makes this tricky and thats why there are funny lengths, in order to treat each cylinder equally.

For flow performance perhaps this is less than ideal, but thats why i used large default diamaters. sorry if thats no use to you - i am focusing on theories, not accuracies right now!

[mikelzapi3]

Thank you for the last drawing , now i can see much better how it works. I don't know how looks the BMW VANOS or other VVT mechanism from inside ( I never seen a proper exploded view of one of those), i only know that they use a mechanism on the camshaft gear as you have done, so is this design a new concept from you, or have you take some ideas from actual systems?

And how much can you change the camshaft angle? it seems that if you can use the whole helical gear length, this angle would be about 45º, but I doubt that this could be made, because as you move the orange part ( I figure that this is moved by hydraulic fluid on the piston that is opposite side of camshaft), if i'm not wrong, the shaft would lose grip. It seems that the guide bits on the inner cone of the orange part aren't enough high to follow the groves of the shaft as the cone comes out completely.

You could change the slopes of the shaft cone and the inner cone to solve this problem, or you could use a cylindrical helical gear instead of a conical, obviously I'm missing something here. Why do you use a conical mechanism?

I'm quite impressed with your job, I like the VVT system, it's simple and it seems to work , I use to think a VVT would be more complicated

[hightower99]

A few questions about the V10...

1. How exactly does your VVT work? I can see that because it is two cones you have fit together they won't work. If the sliding part moves then it will just jam against the camshaft.... it should be two cylinders not cones...

2. Your 3 phase intake is interesting. What reasons do you have for making it tri-phase? Is it to take advantage of "natural supercharging"? or just to match RPM to intake length to reduce pumping losses? Also is it stepless or does it sit in one of 3 positions?

3. IMHO I think the angle of your valves is a little low. It looks like air will slam directly into the back of the valves (this might be intentional to increase turbulance?) also to have a suitable compression ratio you have way too much sidewall un-protected during combustion.

[jediali]

Thank you for the last drawing , now i can see much better how it works. I don't know how looks the BMW VANOS or other VVT mechanism from inside ( I never seen a proper exploded view of one of those), i only know that they use a mechanism on the camshaft gear as you have done, so is this design a new concept from you, or have you take some ideas from actual systems?

And how much can you change the camshaft angle? it seems that if you can use the whole helical gear length, this angle would be about 45º, but I doubt that this could be made, because as you move the orange part ( I figure that this is moved by hydraulic fluid on the piston that is opposite side of camshaft), if i'm not wrong, the shaft would lose grip. It seems that the guide bits on the inner cone of the orange part aren't enough high to follow the groves of the shaft as the cone comes out completely.

You could change the slopes of the shaft cone and the inner cone to solve this problem, or you could use a cylindrical helical gear instead of a conical, obviously I'm missing something here. Why do you use a conical mechanism?

I'm quite impressed with your job, I like the VVT system, it's simple and it seems to work , I use to think a VVT would be more complicated

thanks. the vvt mechanism is tricky to design exactly - you got the jist,all your presumptions are accurate, so it must be somewhat clear. depending on cone geometry up to 45 degree phasing is possible. this is the basis for 90% of cam phasing variable valve timing systems, not my idea, however a cylindrical gear might work better than the conical one i copied from someone -good idea.

[jediali]

A few questions about the V10...

1. How exactly does your VVT work? I can see that because it is two cones you have fit together they won't work. If the sliding part moves then it will just jam against the camshaft.... it should be two cylinders not cones...

2. Your 3 phase intake is interesting. What reasons do you have for making it tri-phase? Is it to take advantage of "natural supercharging"? or just to match RPM to intake length to reduce pumping losses? Also is it stepless or does it sit in one of 3 positions?

3. IMHO I think the angle of your valves is a little low. It looks like air will slam directly into the back of the valves (this might be intentional to increase turbulance?) also to have a suitable compression ratio you have way too much sidewall un-protected during combustion.

1. yes i agree, good idea, imagine holdng the conical vvt part and screwing the camshaft into it, thats how i percieved it to work.
2. i now have a continuosly variable intake on the way, the 3 stage is about matching inlet flow density for inertia filling and charge carriage at low gas speed(longest) and high flow direct reactive gas column for high engine speed (shortest), this depends a lot on collaboration with valvetiming.
3.well yes, i have not done cfa (comp. flow analysis) but you are probably correct. I would like to enginner some sort of stratification(you know?) theory into the combustion chamber to conincide with up and coming direct injection addition.

[LotusLocost]

......For flow performance perhaps this is less than ideal, but thats why i used large default diamaters. sorry if thats no use to you - i am focusing on theories, not accuracies right now!

Ok.. I understand..
Great work anyways

[hightower99]

1. yes i agree, good idea, imagine holdng the conical vvt part and screwing the camshaft into it, thats how i percieved it to work.
2. i now have a continuosly variable intake on the way, the 3 stage is about matching inlet flow density for inertia filling and charge carriage at low gas speed(longest) and high flow direct reactive gas column for high engine speed (shortest), this depends a lot on collaboration with valvetiming.
3.well yes, i have not done cfa (comp. flow analysis) but you are probably correct. I would like to enginner some sort of stratification(you know?) theory into the combustion chamber to conincide with up and coming direct injection addition.

1. ahh ok that is what I was thinking... but the angles you have used would not work correctly. the diameter of the camshaft changes way too fast as it moves and the gear is to open to make good use of this. Most VVT systems in use today use cylindrical helical gears to achieve the same thing. Also what about VVT on the exhaust and what about VVL? having VVT/L on both the intake and exhaust has proven to be much more effective than just VVT on the intake. Are you set on using poppet valves? (just asking because you seem to be interested in theory)
2. Right I can't wait to see your stepless intake!
3. I assume when you say stratification theory that you mean when: The air/fuel ratio of the whole cylinder is less than stoichiometric but the injected fuel is concentrated into a smaller area and in that area the air/fuel ratio is stoichiometric or higher to aid in starting combustion? If so then I can' wait to see what you can come up with. A rather unique idea I have seen in use is using a small mechanical injector that breaths through a carburetor set for a rich mixture (in relation to the air that enters the mechanical injector) and the main cylinder breaths clean air (no fuel) the rich mixture is injected slightly BTDC near the sparkplug and this creates a rich enough area around the sparkplug to combust even though the air/fuel ratio of the whole main cylinder is way lean (around 15.5:1 to about 17:1) saves fuel, makes great power.

[johnnyperl]

1. yes i agree, good idea, imagine holdng the conical vvt part and screwing the camshaft into it, thats how i percieved it to work.

Are you sure that works? As either the camshaft or driver gear slides axially they will immediatly disengage. I dont see how there can be any more than one ratio (1:1) that this works.

[jediali]

1. ahh ok that is what I was thinking... but the angles you have used would not work correctly. the diameter of the camshaft changes way too fast as it moves and the gear is to open to make good use of this. Most VVT systems in use today use cylindrical helical gears to achieve the same thing. Also what about VVT on the exhaust and what about VVL? having VVT/L on both the intake and exhaust has proven to be much more effective than just VVT on the intake. Are you set on using poppet valves? (just asking because you seem to be interested in theory)
2. Right I can't wait to see your stepless intake!
3. I assume when you say stratification theory that you mean when: The air/fuel ratio of the whole cylinder is less than stoichiometric but the injected fuel is concentrated into a smaller area and in that area the air/fuel ratio is stoichiometric or higher to aid in starting combustion? If so then I can' wait to see what you can come up with. A rather unique idea I have seen in use is using a small mechanical injector that breaths through a carburetor set for a rich mixture (in relation to the air that enters the mechanical injector) and the main cylinder breaths clean air (no fuel) the rich mixture is injected slightly BTDC near the sparkplug and this creates a rich enough area around the sparkplug to combust even though the air/fuel ratio of the whole main cylinder is way lean (around 15.5:1 to about 17:1) saves fuel, makes great power.

you know your stuff:

1) yes i agree cylindrical cam phasing mechanism for vvt would work better, ill try that out in time. there is cam phasing vvt on all four camshafts. a cam changing vvt (for lift) is trickier, i have an idea where there are two valve springs and one can be deactivated (see image 1 from an older idea of mine)- i am just trying to keep this aspect original, my ideas! As for poppet valve, M5 V10 uses em! the efficiency is close to hydraulically adjustable valves (more common) but they are best for maintenance. to be honest its a theory i know less about.

2)see picture 2 for a theoretical idea of how its done, the only one in existence i know of is attached to BMW v8s and operates on a similar principal.

3)VW FSI stands for fuel stratified injection. because petrol burns quicker and more redily than diesel, when directly injecting it into the hot compressed air it can burn too radiply and violently. By understanding that air turbulaunce in the combustion chamber speeds up compustion then you will know that by slowing down the air movement (automotive stratification) you can make the petrol burn slower (slower than detonation, but still fast enough to rev really high, see rs4 v8). simple enough really.you where thinking along the right lines, for example this would work by:
- like a diesel always intaking a full measure of air into chamber(this has many advantages)
-but depending on throttle position only injecting (directly into combustion chamber) just enough petrol for combustion while piston rises. this is heterogeneous mixture control
-only exception is at full throttle, where fuel is injected as the air is drawn in through intake ports, rendering it homogeneous mixture control just like any other petrol.

Therefore to do this in my engine i must
-put injectors into the cylinder head
-design porting,combustion chamber,intake manifold, piston crown,compression ratio to bring about a stratification process that keeps air relatively motionless (near point of injection primarily)

please note that this is probably contestable theories that i am exploring through creativity, not ultimate finished product quality - ie those who reply and deliberately nitpick are likely to tell me what i already know and dont care about. feedback is desired though.

1st pic: vvt lift idea?
2nd pic:continuously variable intake tract example,cutaway -longest mode
3rd pic: continuously variable intake tract example,cutaway -shortest mode

[Ferrer]

Amazing job. I actually know close to nothing regarding technical stuff... but it looks like it could enter production tomorrow...

It's intended for road use or for racing?

[jediali]

trying to blend efficiency with 100hp/litre performance, so it might be suitable for a £100k coupe. still so many details to fix though, there isn't even timing chains, or fuel system yet. i hope you can learn from it but tech heads will notice many shortcomings, i have myself.

[Ferrer]

trying to blend efficiency with 100hp/litre performance, so it might be suitable for a £100k coupe. still so many details to fix though, there isn't even timing chains, or fuel system yet. i hope you can learn from it but tech heads will notice many shortcomings, i have myself.

I suppose it's the 5-litre version the one that'll go under the bonnet of the £100k sportscar. Will you be using direct fuel injection?

[jediali]

so many manufacturers are now developing directly injected petrols for efficiency and carbon reduction, plus it improves torque production, so i see sense in it. oddly this engine is set up at 3.0 litre capacity, i will stroke it out from 40mm to achieve 4.5-5.5litres from the 98mm bore.

[Ferrer]

so many manufacturers are now developing directly injected petrols for efficiency and carbon reduction, plus it improves torque production, so i see sense in it. oddly this engine is set up at 3.0 litre capacity, i will stroke it out from 40mm to achieve 4.5-5.5litres from the 98mm bore.

Yes but a 3-litre V10 would be on the small side for a £100k coupe, unless you're planning to combine it with forced induction, which could also be a possiblity.

However the 80x98mm you mentioned makes for a 6034cc displacement, which is a bit too much. As you say from 4.5 to 5.5-litres could be good if you are planning to not use forced induction.

[jediali]

40 stroke, 98 bore therefore 3.0 litre (F1 spec) current layout
60-70 stroke, 98 bore therefore about 5.0 litre region(onroad spec) desired layout

clear (oh and porsche carrera gt has 6.2 v10.)

i dont really want forced induction