VVT swapped NA6
 

Long story short: I'm not a mechanic, but I'm good at figuring stuff out. At least I thought I was. Anyway, I had a friend of a friend who IS a mechanic and has done engine swaps before on several Toyota MR2s do the mechanical and wiring for the engine swap knowing full well the tuning was on me. Now I've got the car, and it starts, but it's terrible and I'm worried if I continue I may damage it.

Other fun fact: the alternator he got (NA8 self regulated alternator) isn't putting out enough juice to recharge the battery so I can't really go on a drive. I'm wondering if there's some setting I'm missing and the megasquirt is trying to regulate a self regulated alternator since the NB2 alternator is ECU controlled.

Car details:
NA6 chassis
MS3 90-93 PNP
Stock VVT Engine, sensors, ignition (sequential)
NA8 Alternator
Running MAP and a GM IAT

It started (not well) and idled decently. However when I grabbed a timing light, holy crap did it look bad. The dot looked like it was at 5:30PM and very, very far off. At this point I'm basically scared to really do anything. My first thought is how the hell did the car start with the timing that far off, and am I supposed to do a massive advance calibration setting in megasquirt? Honestly my first thought was "that dot can't be right." Also, the VVT appears to not be working at all based on the error message.

Another fun fact: I'm broke. I'm getting married soon, so if I can't fix it myself then the car is going to have to sit for a while.

First things: 5:30? Verify your TDC - pull a sparkplug, throw a long screwdriver in, move the crank around till the screwdriver is at the highest point. The harmonic balancers have the capability of twisting, leaving the TDC mark in the wrong place.

NA8 alternator should just work - is your instrument cluster installed?

Stop perpetuating this myth. You do not need the instrument cluster installed to operate an NA alternator. Rev the motor once, the field will charge, the alternator turns on. Rover hasn't had an OEM cluster in a decade and it's still got the same NA8 alternator it had when it was built in 2010.

Sorry, I've been messing with GM stuff too long.

I am dumb, and was looking at the wrong marks. Next up: getting a good alternator.

Well, before you do that - make sure the connections are good. There's a large plug with 2 connections and a ring terminal - make sure they're seated and the nut is tight on the ring terminal.

Connections are good. Voltage checked at the ring terminal versus chassis is 11.5v, so I'm thinking I need to replace it. I've never done this before, but it looks doable. I'm thinking remove intake piping, radiator hose, maybe the A/C fan, and remove it out through the top.

Also I was 3 degrees off on my timing, so at least that's resolved. Now I just need to figure out VVT control.
https://cimg3.ibsrv.net/gimg/www.mia...d95b233ced.jpg
https://cimg7.ibsrv.net/gimg/www.mia...c883db9069.jpg

Holdup - the alternator comes out the bottom. Remove the intake manifold brace (2 bolts top, 1 bolt bottom), remove the undertray, then remove the bottom alternator pivot bolt and the tension bolt, comes out through the bottom. Can be done in a parking lot under jackstands in 15 minutes.

Take the alternator to autozone/oreily/advanced and have them test it. That'll tell us if it's a alternator issue or a wiring issue.

Oh - and yank the battery positive cable, otherwise spitzasparkin.

There's a ground strap from the engine to the firewall that is worth making sure is still there.

It was a bad alternator, and I'm very happy! Easy fix.

Ok, so I have set the correct minimum duty % for VVT, but while following the instructions laid out in https://www.miataturbo.net/megasquir...-please-78480/, I'm not really seeing a vvt test mode so it's difficult for me to really get the exact numbers and the max duty %. Am I missing something? Has megasquirt changed procedures over the past 4 years?

It's just test mode. Press "pulsed", set it to the same frequency your VVT settings are set to, and adjust the duty cycle as the last post in that thread you linked describes.

In reading all these NA6 VVT swap threads - why are people not just using the alternator already on the 01-05 engine? I know there are regulation issues with some years but not much discussion on the 01-05 alternators. Can a Megasquirt externally regulate the alternator if you used a non-internally regulated one?

The answer to this question is that it unnecessarily complicates an already complicated setup. Self regulated alternator is an easy install and an Fd alternator is a straight bolt in upgrade outputting more amps than an nb2 alternator would.