no power until 5200rpm
 

Got my MS2 somewhat tuned, for the VE table anyway, and I can't get rid of some strange problems.

Under 5200 rpm with boost it accelerates very slowly...like there's no turbo slow. Once past 5200 rpm with more than 3-4psi it takes off and makes decent power...somewhere around stock ECU power.

Under 5200 rpm without boost it accelerates very slow...way slower than it should. At 5200rpm it stops injecting? igniting? until rpms drop by 300 then it runs again. Once 5200 is hit AFRs shoot up to 20+. I can do this over and over again.

https://www.miataturbo.net/attachmen...ine=1339468146

Accelerating in boost beyond 5200 and up-shifting is weird.
If the next gear puts rpms above 5200 then fuel/spark is cut and if I stay on with light/medium throttle the car lurches until foot is removed from gas pedal. 20+AFR here too. The throttle variations are from the bucking, no way I could do that so quickly.
If below 4900 there's a bit of hesitation as gas/clutch are applied.

https://www.miataturbo.net/attachmen...ine=1339468146

full specs?

MSM with full intake/exhaust/321cc injectors. Reverant built MS2 Enhanced.

What is the overboost protection set to?

What's the spark plug gap?

What are the injector duty cycles? That would be a good thing to log.

AFR target doesn't mean much. That's just what the MS uses to trim fuel when in closed loop. Usually, once we're in boost, we're operating open loop. VE table is uber-important.

Remember, anytime you see an AFR that high it usually indicates a misfire. Lots of O2 means it wasn't consumed.

None

.028

---- if I know. Is it PW(1-4) in the msl?

If you're referring the it being in the screenshots...well that's just because I like looking at it and seeing all the work VEAL does for me.

Good to know. I'm a total tuning :noob: so this is all a big unknown to me. Don't think I could have picked a better platform to start on, the MS is freakin sweet! So much info available.

post a copy of your tune

ok

Disconnect the connector from the VTCS solenoid. Be ready to get off the throttle if it goes lean. Also, contact me to upgrade to the latest firmware available.

I'll give that a try tonight and will do. Thanks!

What a difference that made! You weren't kidding about it going lean either, I added in a ton of fuel across the entire map. Boost or no boost it runs nice and smooth all the way to 7200 now. Already I'm amazed at just how much more power is made down low and how smooth the power band is. Haven't touched the MBC and boost is coming on quicker and there's at least 2psi more on the top end compared to stock ECU.

here's a durbo in a box
https://www.miataturbo.net/attachmen...ine=1339550004

Car sounds better now too right? Before I unplugged mine it sounded like a rototiller.

If you're looking to make power and already found out you don't need the VCTS shouldn't you remove the flaps completely and free up some breathing room?

IIRC VCTS are some flaps somewhere in the intake to do some warm-up vodoo. They do restrict your intake cross-section...

Have you seen anything showing gutting VTCS makes any measurable difference in power? Everything I've seen shows 1-2hp.

Yeah car sounds much better now. Funny how the intake not being massively restricted will do that. Itching to get out and do some more tuning and it's only been 20 hours. lol

haha I knew it was VTCS hooked up to operate at VICS settings.

VTCS only helps with cold start emissions and idle stability. that's it. If you want to use it, you can set it to remain closed (<60C CLT OR <1700 rpm). That's boolean. you want it open if the car is warm or if the rpm increases. for small turbos, you may even want to drop the RPM value to 1-200 over your highest idle RPM.

Closed it will choke your car like a serial killer.

Where does that go in TS and can I just make it < 200 rpm so it never closes but the solenoid can stay plugged in? Then I don't have to remember to plug it in every 2 years for OBD2.

The orange engine shaped light on your dash will remind you:giggle:

depends on the output you're using. I'm sure reverant can point you in the right direction.