Using MS2 stepper chip to drive VANOS Valve and 3 wire IACV

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davebmw
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Using MS2 stepper chip to drive VANOS Valve and 3 wire IACV

Post by davebmw »

I had some spare time last night so i had a fiddle with my MS2V3.00,
I wanted to sort out the VANOS solenoid and the 3 Wire PWM valve.
My initial thought was to use TIP121's to drive it all on a piece of vero board then it hit me that the stepper chip is sat there doing nothing, what a waste! :shock:

So for the VANOS i set the IAC2 output to change state between 2300 to 4000 RPM (I haven't tried this setting on the engine yet its just an educated guess).
I then use one of the outputs from the stepper pin 37 on the MS2 channel 1 to drive the Ign IGBT (which i have spare due to using the 3 leds to drive the COP wasted spark).

the 3 wire bosch IACV is a little more tricky as you have to lift pin 3 in U3 of the MS2 CPU card. I connected pin 3 to the PWM idle signal on pin 34 of the MS2. This then gives the push pull signal required to directly drive the 3 wire IACV at pins 35 and 36.

I now also have a spare port at the CPU (IAC1) that can be set for pretty much anything really, I'm going to have a play with a second condition on the VANOS so that its not just RPM but load dependant also or maybe a totally different output.
93'BMW 325is M50B25TU, Rebuilt 06/06, JE10.5:1, polish&port. Scorpion BB, K&N CAI, TEJ21 WBO2, '07 M3 Evo 18" 225F, 255R, EBC Kevlar, Bilstien Sprint, Polyflex. Head rebuild Oct'08, OEM+FSE FPR, MS2v3.0_DJB Custom, Extra 2.0.1
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Fred
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Re: Using MS2 stepper chip to drive VANOS Valve and 3 wire IACV

Post by Fred »

Nice, how have you adjusted your tune for it? Or is this all on the bench?

http://www.diyefi.org/files/ms2.v3.ms2e.functions.ods

A pin out I did a while back for ms2. I find it more clear than the manual one. Opinions may vary, accuracy not guaranteed.

Fred.
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Re: Using MS2 stepper chip to drive VANOS Valve and 3 wire IACV

Post by davebmw »

Fred wrote:Nice, how have you adjusted your tune for it? Or is this all on the bench?

http://www.diyefi.org/files/ms2.v3.ms2e.functions.ods

A pin out I did a while back for ms2. I find it more clear than the manual one. Opinions may vary, accuracy not guaranteed.

Fred.
Its purely on the bench at the moment there is a huge thunderstorm brewing overhead so its scuppered my plans of trying it out on the car this evening :roll: but i have got a spare 2 wire IACV and i have had a play with the PWM settings but as expected because its push only not push pull nothing really happens until about 60 to 70 %. i expect the 3 wire will be half open at 50 %.

As for the tune i expect the point where the VANOS actuates will be a tricky bugger to tune but i was thinking about tuning 1 map with no vanos and a second map with vanos engaged then copy over the values in the area where the vanos cuts in and out.
Inevitably the multi valve engine is designed to breathe for top end power the vanos system is there as a compromise to regain some torque and improve fuel consumption. i think the only real way to get the optimal actuation points and smoothness of delivery is to live with it day in day out and tweak on the way to and from work.

What program do i used to view the .ods file, and OK it may not be totally accurate neither is the original IAC1 and 2 are swapped at the stepper driver. :roll:
93'BMW 325is M50B25TU, Rebuilt 06/06, JE10.5:1, polish&port. Scorpion BB, K&N CAI, TEJ21 WBO2, '07 M3 Evo 18" 225F, 255R, EBC Kevlar, Bilstien Sprint, Polyflex. Head rebuild Oct'08, OEM+FSE FPR, MS2v3.0_DJB Custom, Extra 2.0.1
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Re: Using MS2 stepper chip to drive VANOS Valve and 3 wire IACV

Post by Fred »

Actually, a good multi valve engine makes more torque everywhere :-) But the big cams or small cams issue is still present, just not as acute as with less valves.

http://www.openoffice.org for the open document spreadsheet file.

You may be able to use table switching to flick between them as it actuates. The advantage being maybe some sort of delay for the actuator in each direction in code to keep it smooth? You might have to hack that in yourself though.

Fred.
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Re: Using MS2 stepper chip to drive VANOS Valve and 3 wire IACV

Post by BenFenner »

Fred wrote:Actually, a good multi valve engine makes more torque everywhere :-) But the big cams or small cams issue is still present
VANOS is cam timing only, not lift. =/
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Re: Using MS2 stepper chip to drive VANOS Valve and 3 wire IACV

Post by Fred »

It's not duration either, but it still has a significant impact on how much torque you get at any given RPM. It still helps spread the high part of the torque curve wider than it otherwise would be. Even a basic 16V non vvt head like the one on my engine categorically thumps almost any 2 valve design for spread of torque and overall flow at the same time. It's just a balance of cam duration, intake design and where you want the best torque (same for all cammed engines). Some manufacturers choose to choke the top end with long small runners to aid low end torque and I chose to do the opposite with my inlet. Reality is the loss of torque in one part of the curve over another from manifold design isn't that big anyway. Hence I favoured top end :-)

Enough ranting about that, bed is calling!

Fred.
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Re: Using MS2 stepper chip to drive VANOS Valve and 3 wire IACV

Post by davebmw »

I just posted this thread on MSEFI forum to try and help out and i got a warning from the moderator for putting the thread in on its own and referring to it in a response to another 3 wire Idle valve thread.
What a bunch of D****! :o I'm seriously not going to bother posting on there again! whats the point if you try and help out and someone with a god complex comes along and gives you a warning for it! :(
93'BMW 325is M50B25TU, Rebuilt 06/06, JE10.5:1, polish&port. Scorpion BB, K&N CAI, TEJ21 WBO2, '07 M3 Evo 18" 225F, 255R, EBC Kevlar, Bilstien Sprint, Polyflex. Head rebuild Oct'08, OEM+FSE FPR, MS2v3.0_DJB Custom, Extra 2.0.1
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Re: Using MS2 stepper chip to drive VANOS Valve and 3 wire IACV

Post by Fred »

Welcome to the club :-)

The mistake you made was posting on a site that has a major chip on its admins shoulders about "extra functionality" IE, your posts were somehow linked to msextra code and therefore you are an enemy :-) Sorry for spamming your thread again. I can delete/remove/move the OT posts if you like.

To get a better response post on http://www.msextra.com and you will only get ignored if they don't like what you are up to. On the other hand, there are some helpful members there that may/will respond to you.

http://www.msefi.com however is a total and utter waste of time thanks to Lance. See the "moderation" link in my sig ;-)

Fred.
DIYEFI.org - where Open Source means Open Source, and Free means Freedom
FreeEMS.org - the open source engine management system
FreeEMS dev diary and its comments thread and my turbo truck!
n00bs, do NOT PM or email tech questions! Use the forum!
The ever growing list of FreeEMS success stories!
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Re: Using MS2 stepper chip to drive VANOS Valve and 3 wire IACV

Post by jharvey »

Warning, your lucky, I was flat out banned. I received via family gift(s) the MSII V3.0, JimStim, ect. For a cost of about $450. Couple posts at msefi, and now my IP is blocked (from all MS sites), my account has been deleted, and my posts have been removed. As far as I'm concerned it's not OK to sell a product then ban access to the manual that tells you how to use it.

I also don't feel a need to participate over there either.

Sorry for participating in a post jacking like this, at least they are warning now.
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Re: Using MS2 stepper chip to drive VANOS Valve and 3 wire IACV

Post by jbelanger »

Sorry to continue the thread jacking but have you complained to your (or your family's) MS vendor? The vendors should be really concerned that their clients can't have access to the "public" information on the product they sell.

By the way, I'll happily answer any question you have on the JimStim and you're not banned from my web site (nor is anybody else for that matter).

Jean
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