CAM GUY'S , just when you though theres nothing new

[GARY C]

Pretty interesting, I like that he can condense a boring 2 hour seminar into a 15 minute video.

[gunt]

one reason i put it up , that between all manufactures one would think every angle has being worked here , and there's no new idea , well there is !

its interesting from that point alone ,

to me the BMW is a good stab at it but deeply flawed compared to honda

CAMKING'S point was this could be used as a very good control for all around power as would be my view to just because he did not state the obvious that you could run a cam with crap idle and start at a more aggressive point and build from there there for pure power it would still out perform most .

look at the control of I vtec and the mivec , the cam deg control is unreal at any point, and there's is electro over hydraulic , so electric servo motor would have to be faster and more precise

just think of this in boosted applications

don't knock it due to no lift , engine designers are emission compliant , power is very easy for them , look at the new amg 4cylinder merc near 500bhp from the factory 2.0 with full warranty , so maybe they add lift to the system in a few years as toyota did .

but currently there are very few options bar paying for a patient or do like the video, coming up with a hole brand new way to create lift .

NOTE did any one notice the cam lobes being slipped on , no camshafts to be purchase just drop on lobes , should be cheaper

[Dave Koehler]

Logan has his tape measure out again.

[modok]

BMW has been using a variable lift/duration system since over 10 years ago, which was complex to look at, but basically was a variable stroke reciprocating cam lobe.

This is a different way of doing it, very interesting!
Very similar to how the Antikythera Mechanism gearing for the moon position
https://www.theposthole.org/read/article/15

[Krooser]

I don't think I could turn that knob fast enough to make the engine run better... even harder when you drive a manual trans.

[408swinger]

My understanding of VTEC is that it uses 2 sets of lobes plus phases the cam a number of degrees .
So wouldn't that vary all aspects ?

[Sparksalot]

Thanks for posting this gunt, it is very interesting. The kinematics are fascinating and I can fully understand why it took so many years to develop a reliable design for mass production.

[gunt]

by 408swinger » Sat Mar 07, 2020 6:17 am
My understanding of VTEC is that it uses 2 sets of lobes plus phases the cam a number of degrees .
So wouldn't that vary all aspects ?


the honda V-tec had say , 3 lobes for 2 valves 2 low lobes very similar , a low cam for tq , then at a given rpm the followers were locked and it rode on the 3rd lobe driving the 2 valves a cam with completely different deg and lift ,

but I V-tec is the ability to advance the intake cam up to 50deg at any point in the rpm or load range changing over lap , it starts from a retarded point , but at 2200rpm you could target 22deg and 2800rpm 34deg, 3500rpm 18deg, 5000rpm 40deg and so on , this can be used on the low cam and they you have the ability to vary it on the high cam ,

on the other point of pumping losses , and throttle , sometimes its very usefull , as the newer engines have to use vac pumps for brakes , so theres a trade off

[408swinger]

by 408swinger » Sat Mar 07, 2020 6:17 am
My understanding of VTEC is that it uses 2 sets of lobes plus phases the cam a number of degrees .
So wouldn't that vary all aspects ?


the honda V-tec had say , 3 lobes for 2 valves 2 low lobes very similar , a low cam for tq , then at a given rpm the followers were locked and it rode on the 3rd lobe driving the 2 valves a cam with completely different deg and lift ,

but I V-tec is the ability to advance the intake cam up to 50deg at any point in the rpm or load range changing over lap , it starts from a retarded point , but at 2200rpm you could target 22deg and 2800rpm 34deg, 3500rpm 18deg, 5000rpm 40deg and so on , this can be used on the low cam and they you have the ability to vary it on the high cam ,

on the other point of pumping losses , and throttle , sometimes its very usefull , as the newer engines have to use vac pumps for brakes , so theres a trade off

Thanks for the in depth explanation .
I am a salesman for an Acura store as well as the NSX specialist . But I cant get info like this from Acura ! Anything more technical than tire size and they just shrug ...lol

[gmrocket]

I think it’s pretty amazing being purely mechanical.

This concept could used in ohv V8’s but would need a pretty big cam tunnel

[CamKing]

For performance. Performance operation is in a narrow range,

I guess they don't have road racing in Michigan.
I guess nobody in Michigan wants to drive their car on the street, and drag race it on weekends.
I guess circle track racers in Michigan don't need power on re-starts.

[CamKing]

Here's why changing duration is more important then changing lift and area, on a variable system.
With today's technology, we can change a lot of parameters to make the engine more efficient. Timing, fuel, Intake and Exhaust centerlines, lift, duration, runner length, etc, but the one thing we're normally stuck with is Port MCA. The cross-sectional area of the port has to be big enough to feed the engine at max RPM, but that means it's too big, at lower RPMs. at lower RPM, where the velocity in the port is lower then what would be most efficient at that rpm, the best way to crutch it, is to reduce intake duration without decreasing lift. and advance the intake centerline. This gives you a shorter, stronger pulse, which increase the max velocity in the port, compared to leaving the duration alone, and reducing lift.

[gunt]

408swinger

i use these for lecturing , there the easiest way , but for every manufacture that has a system there is an animation , look them up and compare ,
good to see a sales man here , at least you have the interest . look at the simple first v-tec first and then I .


https://www.youtube.com/results?search_ ... +animation

going back to other engines , the biggest part of no throttle is going to be direct injection ,
and back to any using hydraulics , even look / test how much presure they use and the new variable oil pumps , how much better off would an engine be if the best of all systmes could be used

there is no mention to engine efficiency on this engine only 4% [ or whatever ] it is over its base but look at the k20a2 bmep , by comparing all other engines this nearly shouldn't be possible to make such a huge difference

[408swinger]

I understood how the VTEC works mechanical but could never get info on degrees of retard/advance .

[SchmidtMotorWorks]

seen this look seriously interesting for the after market ,

Clever idea for an OEM, but not for the aftermarket.

What manufacturer in the performance aftermarket do you imagine could engineer and manufacture that design for a performance engine?

Consider, that a DOHC retrofit (vastly smaller challenge) has never succeeded in the market even though some decent ones have been developed. The best that comes to mind was Richard Mosers DOHC SBC head that was made with Crane funding. Richard told me they cast about 20 and sold only a few sets.

Even if there was a manufacturer in the performance after market that could make it (there isn't), would the cost of it be viable?,,,no way, not even close.

Then there is the complexity, just look at how perplexed many people are by very simple pushrod rocker arm geometry issues. That rules out 90% or more of the market.

There is a good reason that the vast majority of parts made by Edelbrock are about the same as the parts they made 30 years ago and fit engines that have not been made for a long time. The market prefers simplicity and low prices.