tomtom84

the timing on this post is amazing, I'm swapping a k24z7 into something and am wiring my cam/crank signals right now to test start the engine. anyone planning to run a turbo?

thanks for sharing all this! I'll report back on my progress also.

currently planning to weld/grind the exhaust trigger to single tooth and go from there.

240_to_miata

iTrader: (2)

All you guys going k24z on megasquirt… where were you a year ago??? Lol.

I am going turbo but not until next year. I wanted to get it running and driving first … but I’ll be down about 70hp from my old setup so I’ll be craving a turbo soon.

tomtom84

Lol. I started my project in April, kids have taken a ton of my time and I had never even looked into kmotors before this.

plan is to get it running out of car, then stick in car with a 35r ish turbo at low boost and see what happens.

rabid

You shouldn't need to grind the trigger wheel. I used polling and not edge trigger.

240_to_miata

iTrader: (2)

I agree pole would work but honestly 5 minutes with a grinder makes it so you don’t need to deal with that. I did mine on a Bridgeport.

tomtom84

I am using a k24z7 as my good engine and have a dead k24z3 (mock-up motor) that I can pull parts from. I’ll try polling and will still plan to modify my extra exhaust trigger.

did you just grind all but the single nub off? I thought it had to be welded and then machined flush. I have access to machine shop stuff, so I’ll see what works. I’m still finalizing some wiring and have to be out of town, so it might be a few weeks.

240_to_miata

iTrader: (2)

Yeah I just machined it so there was only 1 tooth. Unfortunately I chose the one that is very close to being read at tdc which probably wasn’t wise, but it worked.

rabid

What throttle cable did you use? My stock NB2 cable stretches beyond the bumper so it's too long.

rabid

Got my VVT working!

tomtom84

Realized I could test with starter fluid, so confirmed mine seems to run. Did poll level, “high” and check at tooth 0.

woot! I’m running dw1000, but normally use id and realized that map was for id1050s.

Mine is actually going into a 997, so super cool to be able to all use similar things.

tomtom84

awesome! Mind sharing your map? I am going to post mine as soon as I have it running, still working a few things, but I think it will be great to compare setups.

rabid

I'm not sure what tooth is best to choose. I did a bunch of high/low tooth mapping on paper by turning the engine by hand and checking the voltage from the crank and exhaust cam. I determined that around crank tooth 3 or 4 was the end of the 2nd big tooth on the cam. So I set it to poll high at tooth 4.

I posted it in my thread in this same sub forum. I wouldn't copy anything just yet. Nothing is tuned. It's just running on low cam. I am trying to figure out what the stock ecu PWM frequency to the VTC is. No one has that information and I don't have a car that I can put my scope on.

240_to_miata

iTrader: (2)

I found some evidence online that 300-500 range would work. I’m starting with around 350 because as I understand it this frequency must be the same as the idle valve and that seems to be a number that might work for both. Time will tell. I hope to finish my intake in the next week so I can Street drive.

240_to_miata

iTrader: (2)

I have good news and I have bad news…

just did a short 3 mile drive.

good news: VVT works great. Angle tracks very well against target. A slight overshoot and lag so I’ll play with my PID settings and get that dialed in.

bad news: I lost sync at about 5500rpm causing me to limp home the last 1/4 mile on 2 cylinders. Log says “reason 2” which means I’m getting a phantom tooth. I need to understand if a pull-up is required on the crank sensor or not. Being a rev built MS3Basic for a Miata one would assume there is a pull-up on the crank but I’m not sure.

I may also just try some filtering.

rabid

Did you ever lose sync while free reving it?

What are your vvt settings? What range of pwm output do you see?

240_to_miata

iTrader: (2)

Can’t say I ever free reved it to 6k lol. Guess I need to try.

I just shut down the computer. I’ll post my VVT settings tomorrow.

tomtom84

I messed with mine again yesterday... found out that I must have a short somewhere in my harness that is making the cam signal drop completely and it was only firing during cranking due to batch fire. I'm out of town all this week, but my engine mount should also be in the mail.. so hopefully I'm driving by end of month and can help provide more input.

More background on my setup... ms3pro evo with ls24x harness that I found locally for cheap, so I've modified it and so far have verified crank/spark/inj/tps/iat/clt, but the cam signal is not reaching the ecu ( I also verified voltage at the sensor and output on intake and exhaust.. but it never makes it to the ecu). I'm running it on a workbench before sticking it in the car to make sure everything is good.

240_to_miata

iTrader: (2)

So I've emailed Reverant with no luck. I know he doesn't do PMs on this site anymore... so I am crossing my fingers that someone else can help.

Does anyone know what Pull-up's are on the MS3BASIC CMP and CKP circuits? Back when I had a MS1 I know the standard mod for a Miata was 12V pullup on CKP and 5V on CMP.

Before I go modifying anything or adding external circuits I want to know what is existing. Also if anyone has any other ideas on how to ensure I don't loose sync, I am all ears!

Thanks!

rabid

Have you looked at the hardware guide for it? What inputs on the board or ms3 cpu are you using?

240_to_miata

iTrader: (2)

I don’t know of a hardware guide for reverants board. Here is the only manual I am aware of for this product. It’s not a standard megasquirt main board.

https://www.mslabs.gr/documentation/...7_v32_fw14.pdf