The VAST system won't give you spark cut as it will just return to 10 degrees timing when you stop sending a signal to the IGT wire. However, you can use spark retard and a fuel cut to setup a rev limiter.
 
To test the TVIS, I would set the turn on value to 2000RPM and then stand at the engine bay with the car idling and blip the throttle to see if the TVIS actuator moves. I've just downloaded your files and will have a look shortly :)

I've got the car running properly with the coil being fired from the Megasquirt. I still seem to be suffering from a loss of power past 5000rpm over the factory ecu though so might need to take it to a tuner to have a look at it.
 
However. as I've completely disconnected the VAST from the coil my tacho doesn't work anymore.
 
Does anyone know how I could get that working again? I'm useless with electronics. Is there a cable from the VAST unit I can splice into and hook up to the coil or how do I revive the tacho?
 
Cheers,
Timmy

xtimmyx
I've got the car running properly with the coil being fired from the Megasquirt. I still seem to be suffering from a loss of power past 5000rpm over the factory ecu though so might need to take it to a tuner to have a look at it.

While not a problem, I noticed that you have fuel and spark tables that are tuned for a boosted motor (100+KPA).

I assume these are Jerry Hoffmans old 4AGTE tables. Some more 4AGE specific tables could bring some benefits, even if minor.

Domma_aw11
would mine help him out?

Difference in compression and cams would probably make it easier to just run some TunerStudio generated maps.

Looking at the logs, it doesn't look like there are any major issues. The AFR's are reasonable, the fuel looks fine and there are no errors popping up. You have a few minor things like the TPS not being calibrated (showing 103.7% at WOT).

You could do with a little more timing from 3800 RPM on wards.
I found with my old 16V and 20V, both motors liked 36 degrees of timing for a large portion of the table in WOT.
Some similar chatter across the interwebz, but each motor is different.
 
I would set it to something similar to this. (You can ignore my OCD adjustments of the table rows values...)

 
See how it performs with the addition top end timing and see what the butt cheek dyno says.
However, ideally to find out where the motor can gain or lose, you need to get it on a dyno.

Domma_aw11
oh, a lot of people told me 36deg was to high, mines down to 32deg, but its gone slower, but then I need to tweak my AFRS, but also, my car doent like making power over 7k... so ive been pondering shorter stack, from the head to the end of the stack is over 300mm

Each motor is different, some might fine 30-32 is the upper limit, others might take 36-38+. The only way you will know the best value is to get it onto a dyno and look at the Max Brake Torque (MBT).

I'm a little rusty on runner length calculations at the moment, but last time I was looking at 4AGE's the maths was showing a longer intake was needed. Tuning for a peak of 8000rpm and 285 duration cams, you needed a ~780mm runner (Valve to Bellmouth) to catch the 2nd order wave. A ~310mm runner will allow you to catch the 5th (3 orders weaker then the 2nd).

This is all just maths and theory, when applied to a car, you can get a different result due to a whole range of variables the maths cannot tell you. The best way is to make up a variable length slide runner to adjust while it's on the dyno and see what length produces the best results.

Had a novel written up as a reply, but my web browser crashed, so here's the cliff notes version.
 

Domma_aw11
I remember you say something like this to me, and me not having a goddam clue, cayne was also telling me the same thing, I cnt go longer runners as il have to run them in the boot...

Get creative.

Seen a 20V AE92 with a 180 bend in the runner and the velocity stacks sat above the head. I think the runner was around 500mm in length.
 

Domma_aw11
but also, can I use det cans or is there no point?

They are good for tuning, but useless for street driving. In my opinion, easier to do a good tune on the dyno with some safety in it. Additionally you could always add something like a knock lite if your concerned.
 

Domma_aw11
and when we did that dyno run day, were u on the MS or the stock ecu? could u post that dyno chart up?

Stock ECU.

Domma_aw11
I cant believe I forgot out the AE92, my mate had that setup in his with a BT20v.. not bad idea.. the reason im more for road tuning is still cant find a dyno tuner, so trying to see stock afr maps and what kind of stock spark maps are out there to give me a reference. because on the stock ecu my car went bloody HARD!!!

Road tuning is fine for dialing in your fuel tables, but it's impossible to do ignition tuning. You need to get it on a dyno and have a look at the torque at each timing setting.
 
I highly recommend that you sign up to HPA and watch this webinar.
https://www.hpacademy.com/previous-webinars/055-optimising-ignition-timing-mbt-timing-haltech/
It will give you some really good insight on the subject while giving you a live demo (350Z).