Electronic variable vane control

Klatta Klatta

185

03-23-2009, 07:40 AM #46

(03-19-2009, 11:45 AM)GREASY_BEAST I agree that electronic rack control would be ideal, just not worth the PITA of relocating the oil filter without a good reason (like a Myna pump), which it doesn't seem that anyone around here has.. Basically, and maybe I'm just being narrow-minded, I don't see how it could help appreciably on an IP with stock components, other than adding a certain level of engine protection, some more advanced smoke control, and other superfluous things that don't make the car go faster.

I don't think you'd have to relocate the oil filter housing... Personally, I'd use the IP off of an OM606, which has everything already taken care of. As a computer engineer I'm not exactly the best person to have fabricating things!

EDIT: With M-pump engines you would get more power if you use the OM606 pump. It has the larger 6mm elements instead of the 5.5mm in the older engines. It isn't going to get you 400HP, but will still be a nice improvement!

(03-19-2009, 11:45 AM)GREASY_BEAST I'd agree with that, and go so far as to say even electronic wastegate control on a "normal" turbo might yield some benefits like quicker boost rise and more stable, accurate control over maximum boost, cruising vs performance settings, etc.

Yep! A friend's '96 6.5L does all that you mention. At any kind of cruising it only uses the minimum boost necessary to burn the fuel, and, if you get into it, boost is there instantly! Cool

(03-21-2009, 09:54 AM)GREASY_BEAST Might it be possible, with an Arduino board and a voice coil actuator, to remove the mechanical governor and make governance of the engine an electronic affair?

That's what I would do on my 61x based engines, on the 60x based engines I would get the OM606 electronic pumps. It already has the rack control and *accurate position sensors*. Plus, we already know that it works. Smile

On my 61x engines, I would like to remove the guts inside the governor, and directly link the external linkage arm to the rack. I would use the cruise control actuator to control that, with my software controlling the actuator. To those doubters about that actuator not being accurate or fast enough, I've used it as a throttle linkage actuator on a 6.5L Hummer, and it worked great. It is extremely powerful, fast, and accurate. Most importantly, it has an electromagnet that can be turned off and a spring will then return the external arm to its minimum position.

(03-21-2009, 09:54 AM)GREASY_BEAST The software would be dead simple to write, I'm pretty sure with my limited experience I could do that in an afternoon

No offense, but HAHAHAHAHHAHAHAHA. ROTFLMA. Wink

You could probably get something that would move the rack in an afternoon, but there is no way I'd put that on my engine! Also, keep in mind that all of these actuators will require additional power electronics to control them. Most microcontrollers can only output 20mA per pin, and actuators can require *significantly* more than that. Especially when you change positions very quickly!

(03-21-2009, 09:54 AM)GREASY_BEAST The weak link (I guess) would be accurate sensing of the engine RPM?? Could one just use the tach sensor for this or would you need a more accurate reading?

Totally use the tach signal! There are chips that will take the, IIRC, variable reluctance sensor and convert it to a digital signal for the micro. If it is already done, I'd just use that. No sense in re-inventing the wheel. Wink

(03-21-2009, 09:54 AM)GREASY_BEAST Another weak link might be the sensitivity of the actuator?

Bingo!

At idle the amount of fluctuation in the rack is very very small. Equally important is the accuracy of the rack position sensor. I believe the OM606 pump does not use a simple potentiometer for position feedback, but some kind of variable inductance sensor, which I would imagine is non-trivial to sense. There might be an integrated IC that would convert it, but I don't know for sure. The cruise control actuator does use a potentiometer though, so that one would be much easier to implement since you could directly hook the sensor up to the ADC on the micro.

(03-21-2009, 09:54 AM)GREASY_BEAST Would it also reduce the cost of swapping elements? It seems to me that there would be a lot less "shop time" billed by an injection shop if all they had to do was make sure each element is synched to all the others, and not mess with the governor adjustments.

Forced... stop reading now. Wink

For the OM61x pumps you could replace the elements yourself. The synchronization is mainly performed with the pump's camshaft, and the most important part of adjusting new elements is balancing the amount of fuel delivered. The MW pumps have external adjustments for that, and with large enough graduated cylinders you can tune those yourselves. Yes, I know Forced, it won't be 100% perfect, but I think we can get to 90-95%. We will always disagree on this...

With an M pump it's more difficult since the individual fuel quantity is controlled by shims accessible through the side plate. I would probably send that off to a shop.

Long story short, it should make things cheaper. I don't know how much cheaper, but every penny counts.

(03-21-2009, 09:54 AM)GREASY_BEAST Just a brainstorm..

Yep, that's how cool things always happen Idea

This post was last modified: 03-23-2009, 08:06 AM by Tymbrymi.

John Robbins
'05 E320 CDI - 118k - Faaaaaast!! Angel

'87 300TD - 317k - Cracked head... but an OM606 is on the way! Undecided

'79 300SD - 295k - Bad engine = project car!