Twiss' supercharger+EFI

[Rhinoman]

Mine is an 8V so the timing is different, I can pull the timing from the 16V though - I did start building a prototype daughterboard for the Denso ECU, it only needs a little work to finish it. The fuel injection dizzy has no mechanical advance (after 1990), I've never bothered checking where it actually triggers, I just adjust the base timing by fixing it with the scan tool and rotating the dizzy.

[twiss]

I think its 8* but will make sure before I set it. Going to use a cam position wheel so im going to have to get it precise before i weld it on!

hmmm autodata says 5* +/- 1 but I'm not sure I believe that!!!

[Rhinoman]

16V is 5 degrees, a 16V usually runs less advance than an 8V because its a better combustion chamber shape.
What cam wheel are you welding on? if you're using a missing tooth then it needs to be indexed to TDC with the missing tooth at something like 45 degrees BTDC so you sync up before you get to the firing point.

[twiss]

OK 5* is good...

Yeah I was planning on using a missing tooth 36-1 wheel... will probably weld it on, but might get a solid one and spacer and bolt it on instead...

As I would be changing the TDC in the ECU settings, it shouldn't matter if I run it at 90* before should it? make it a bit easier to work out.

I was thinking about doing it 180* out. using the opposite side of the wheel (without the missing tooth) would make it easier to line up with precisely top dead center

If you can get the spark advance table from the 16v ECU that would be amazing!!!

Also, apparently standard injectors are high resistance on the 16v so I can use them

[Rhinoman]

The tooth really needs to be closer to TDC to get a good sync, with a 36-tooth then spacing it at a multiple of ten degrees would be better. Having given it some more thought the 16V Vit timing table is airflow v RPM so won't directly relate to what you would be getting with a MAP sensor. I may be able to get the timing from the Baleno, I'm working on that at the moment.

[twiss]

Well any kind of a rough guess on the timing advance is good at this point! I have been trying to find out how much advance a regular dizzy gives but haven't found any figures yet.

Yeah I will be using MAP for now, but might move to a MAP/MAF blend... does the 16v vit engine come with a MAF sensor as standard?

I can always attach the trigger wheel roughly 45* before, then measure it precisely when its on!

[Rhinoman]

The early 16V with the Denso ECU uses a Volume AirFlow meter, the later 16V with the Mitsu ECU uses a MAF. The MAF is a better system than a MAP because it directly measures the mass of air rather than having to approximate it from a VE table.

[twiss]

I did find out last night a friend has just bought a vit 16v so i may go measure it with my timing gun...

Is there any benefit to MAP over MAF?
MS gives the option of using them at different RPM ranges

[Rhinoman]

A MAP/MAF blend is usually used with lumpy cams where the MAP reading is unstable at tickover/low RPM. Most people run a MAP because data for the MAF can be hard to come by, plus you may run out of range running boost. I don't know how MS implements MAF these days.

[twiss]

Well the vit engine comes with the MAF sensor so I can have a fiddle around with it at some point, but I will use MAP for now just for ease

Does the vit 16v have an IAC valve?