VVT ideas and testers

[adamnreeves]

I've just found a small bug in the firmware that _might_ have impacted VVT users in all firmwares up to and including pre-1.1 beta19.
It looks like there might have been a conflict between an EAE setting and VVT causing the cam position to be miscalculated. This is addressed ready for beta20.

James

In the new few weeks I will be helping a friend install a Ford ST170 engine. Have MS3 running pre-1.1 beta 19 and will be using this new VVT development. Using the default EAE settings. Is there a risk we could run into this issue? If so when is beta20 due? Thanks.

[Hiluxfan]

Hi James
I am new to MS and have some questions. I want to install a Ms3x on Lexus 3uz motor. Has anyone done the development for VVTI? I am more than willing to help with it if not. Are you confident it can be done?
Currently I am still not sure if I should buy. I dont want to sit with something that I cannot use.
Many thanks

[jsmcortina]

Hi James
I am new to MS and have some questions. I want to install a Ms3x on Lexus 3uz motor. Has anyone done the development for VVTI?

Do you have the technical data on the crank/cam patterns for that engine - that is a requirement for VVT dev.

All the core VVT code is in place and working. Some engines need special decoders, others work with the existing decoders.

James

[Hiluxfan]

Hi James
Thanks for your reply. If you dont mind I can send you a small write up via email. Its a bit big to post. Whats your address?
Many thanks

[gross polluter]

This may have been discussed before in this thread or others, so I think I'm not the only one having this problem.

I think a useful feature for VVT would be to have either a startup delay or a CLT based timing trim. I've read that a few other users here are finding that the timing values that work at operating temp aren't necessarily the same values that work properly for a cold engine.

The issue I'm having is that my oil pressure rises slowly when cold, takes about 3-4 seconds to come to full pressure after a cold start. What is happening during this time is the VVT solenoid goes full duty to advance the cam, since no advance is taking place with little oil pressure. Once the engine comes to full pressure the cam will overshoot its target, causing the engine to stall.

I think having the cold start trim, as suggested by other users, would help overcome this issue. Otherwise, something as simple as a delay after startup before the MS starts targeting cam timing, to wait for the oil pressure to become effective for cam control.

Is anyone else having similar issues, or am I setting my cam timing settings too aggressive? There is no overshoot or timing oscillations otherwise.

[Hiluxfan]

Hi there

I will be fitting a MS3x to Lexus 3UZ motor. It has dual intake VVTI and I want the MS3x to control this fully. I can help with the development but I need the hardware first.
My current shopping list looks like this:
1. MegaSquirt-III kit with V3.0 PCB
2. MS3X expansion card
3. MS 3X daughter board
4. Jim Stim V 1.5 with wheel sim
5. Jim Stim X
6. Jim Stim power supply
7. USB Tuning cable
8. Lead bender
9. Jumper pack 10
10. PWM IAC Valve controller
11. 2x VR conditioners (No longer available from JB Performance, looking for alternative)

I want to get the ECU built first. I’ll do the wiring myself and get the Inovate O2 and other sensors at a later stage.

If there is anything that I have missed or anyone can recommend, please let me know.

Thanks!

[racingmini_mtl]

11. 2x VR conditioners (No longer available from JB Performance, looking for alternative)

There is a newer version available: http://jbperf.com/dual_VR/v2_0.html#Buy.

Jean

[Hiluxfan]

Thanks Jean
Can this be built into the MS case? By the looks of it I would think so as it is very small.

Ive done more reading and it looks like I wont need the PWM IAC Valve controller seperately. The MS3x can drive the stepper motor directly.

[bubba2533]

Thanks Jean
Can this be built into the MS case? By the looks of it I would think so as it is very small.

Ive done more reading and it looks like I wont need the PWM IAC Valve controller seperately. The MS3x can drive the stepper motor directly.

Yes, infact I have the 2.0 board inside my MS3 case and it runs great.

Also, there is a large difference between a PWM IAC Valve and a stepper IAC Valve, so I suggest reading up on them.

[jamies]

Im looking at setting up a megasquirt 3 on a W12 engine, and would also like to run the quad VVT
what is involved in having the MS3 Igniton and VVT work with the cam sensor patterns as per in the attached document?

[jsmcortina]

The cam pattern is the same as the VW and LS2 VVT pattern. Using "poll level" as the cam input type and set 4 teeth and it should work ok. Nothing special required.

James

[jamies]

thanks james

[dfzuntor]

HI
Is there any possibility to add a second vvt table for intake and even exhaust??? I am running a Honda Civic that have the variable valve lift technology, so it will be better to have a vvt table for Low cam lift and a second one to High cam lift, This because originally it works like that, and I think that some of my issues are that at low cam It works perfect at X angle of cam (intake in this honda), and in high cam it doesn't likes that X angle. The same thing is needed for a second spark table, but I can adjust it using table switch by RPM (depending on the cam lift change point).

Thanks
David

[jsmcortina]

How are you controlling your cam lift change point?
Why do you need two tables?
e.g. if lift change happens at a fixed point then tune for high lift above and low lift below?

James

[muythaibxr]

I agree with James... I don't understand why switching tables would be necessary here... just tune the lower part of the table for the lower lift, and the higher part of the table for the higher lift, and space the bins around the lift change very close together to get a quick valve timing switchover.

Ken

[adamnreeves]

Tried turning on vvt settings in beta20 and I am told by ecu that trigger wheel incompatible. I am using EDIS .

[AbatelliCristian]

Hi James,
In my engine s65bmw, I see the difference in the neutral duty between Bank1 and bank2. Is possible insert the neutral duty for single solenoid?

Is possible insert the tooth log for all sensor?

Thanks

[jsmcortina]

Tried turning on vvt settings in beta20 and I am told by ecu that trigger wheel incompatible. I am using EDIS .

Yes.

[jsmcortina]

Hi James,
In my engine s65bmw, I see the difference in the neutral duty between Bank1 and bank2. Is possible insert the neutral duty for single solenoid?

Even without the neutral duty set, the VVT PID should track all four cam positions.

Is possible insert the tooth log for all sensor?

Not presently no.

James

[adamnreeves]

Tried turning on vvt settings in beta20 and I am told by ecu that trigger wheel incompatible. I am using EDIS .

Yes.

Thanks James. Is this because the angle of the cam is in crank degrees and MS does not know that with EDIS?