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-   -   EBC is useless! (https://www.miataturbo.net/megasquirt-18/ebc-useless-28001/)

skidude 11-11-2008 12:49 PM

EBC is useless!
 
<rant>I got the solenoid hooked up, and I have MS tuned as best I can, and it sucks.

My target is 12psi

I overboost (cut is set to 15psi) in the morning when it's 40F, I only get 11psi in the afternoon when it's 60F and then I overboost again when it gets dark and drops back down to 40F. Not to mention that the first three gears spike to the fuel cut then settle at ~10psi.

And it's only going to get worse, since the winter is coming and it will surely overboost a lot when it's about 0F outside.

I'm glad I put in that switch in the dash so I can just switch to the 7psi wastegate most of the time.</rant>

So, is there anybody, anywhere that is working on a better closed-loop code for MS?
I'm taking a controls class (mechanical engineering, University of Maine) this semester, and I'd look at it myself but I have no idea how to program anything. I don't even know how to get in and look at the programming for MSnS.

Braineack 11-11-2008 12:52 PM

how hard is it to hook the laptop up and lower the DC% and up the overboost values while it's cold out?

johndoe 11-11-2008 01:11 PM

It is annoying, especially at this time of year when the temperature can vary greatly. I ended up just raising my overboost limit and setting the DC table to run my target psi in the warmer temps. It can spike for all I care as long as it keeps it from hitting overboost.

skidude 11-11-2008 01:15 PM


Originally Posted by Braineack (Post 329141)
how hard is it to hook the laptop up and lower the DC% and up the overboost values while it's cold out?

It's a royal pain in the ass to have to change my DC% table twice a day. I don't have a problem having 3 tunes (winter, summer, spring/fall) but I won't re-tune my boost every morning, noon and night.

What are the options for electronic boost control, anyway? I know MS has an open loop controller, and a sucky closed loop control. Are there any standalone EBCs that do closed loop well?

TonyV 11-11-2008 01:30 PM

^can u pm me info on that wg switch setup you have? Or link to thread so as not to jack this one?

Braineack 11-11-2008 02:40 PM

1 Attachment(s)

It's a royal pain in the ass to have to change my DC% table twice a day.
I mean, I just lowered my values something like 5% across the board and found a happy medium...I might be leaving a pound of boost on table if it hits 60*F on the way home from work, but I'm also not out racing SUVs in rush hour...


What are the options for electronic boost control, anyway? I know MS has an open loop controller, and a sucky closed loop control. Are there any standalone EBCs that do closed loop well?
Standalone EBCs do a much better job at closed loop. I always had the idea of, since you have a kill switch like me, is throw a MBC in the loop to achieve your target when it's cold....so you may be missing out on some spool, but you'll be bale to maintain your target the manual way.


Originally Posted by tvalenziano (Post 329160)
^can u pm me info on that wg switch setup you have? Or link to thread so as not to jack this one?

Just a switch on the EBC line. Kill the ground to the solenoid and it fails open, makes for two-cars-in-one:

Attachment 210077

skidude 11-11-2008 03:55 PM


I mean, I just lowered my values something like 5% across the board and found a happy medium...I might be leaving a pound of boost on table if it hits 60*F on the way home from work, but I'm also not out racing SUVs in rush hour...
I did the same, so now between morning and night I fluctuate between 9ish and 13ish. I'll probably just run this all winter, since when I put the snow tires on I'll probably just run the wastegate anyway (no need to make the first 3 gears useless when the first 2 will be anyway). Hopefully by spring there will be some sort of upgrade to the closed-loop control in MS.


Standalone EBCs do a much better job at closed loop. I always had the idea of, since you have a kill switch like me, is throw a MBC in the loop to achieve your target when it's cold....so you may be missing out on some spool, but you'll be bale to maintain your target the manual way.
I checked on ebay and an electronic boost controller is more than $200. I guess that's out for now. Seems stupid-simple though; plug it in, push a button until it says "12" on the screen, and hit the go pedal.

I'd be ok with the MBC in the loop except that I sort of like it defaulting back to the wastegate. I haven't tried it yet, but I imagine that my snow tires are goinig to suck even at 7psi.


Just a switch on the EBC line. Kill the ground to the solenoid and it fails open, makes for two-cars-in-one
Yep, I had a switch in the dash from the PO that wasn't connected to anything, so I just used that. It's handy behind the turn signal stock on the bottom of the gauge hood, but it's black and unlabeled so nobody will think to play with it. I put it on low boost before I let other people drive the car.

cjernigan 11-11-2008 04:03 PM

I don't see why you guys have issues. I hit 14 psi when its 40* out and 12 psi when its 80* out. My overboost is set at 18 and I tuned for 13 psi at 60*. Pansy whiners.
Maybe you should insulate your EBC solenoid with some thermal wrap and tuck it close to your engine somewhere so that by the time you can get into boost and your engine is warm your solenoid is warm too and you won't be overboosting like crazy. The thermal wrap is just to protect it from overheating.

Braineack 11-11-2008 04:05 PM


Originally Posted by cjernigan (Post 329212)
I hit 14 psi when its 40* out and 12 psi when its 80* out.


pretty much the same here...the main thing in my case was the boost ramp up rates...comes on a lot stronger/faster in the cold.

skidude 11-11-2008 04:08 PM


Originally Posted by Braineack (Post 329214)
pretty much the same here...the main thing in my case was the boost ramp up rates...comes on a lot stronger/faster in the cold.

That seems to be my real problem. In the cold, the boost comes on really quick and overshoots, crashing into the overboost and then settling down much below that. I would guess I wouldn't have that problem with closed loop or a MBC

cjernigan 11-11-2008 04:13 PM

Guess I don't know why you don't just tune for 10 psi and then set overboost to 15.

skidude 11-11-2008 04:19 PM


Originally Posted by cjernigan (Post 329218)
Guess I don't know why you don't just tune for 10 psi and then set overboost to 15.

Yeah... that's what I have to do, not what I want. I want 12psi, all the time, day and night, winter and summer. That's what EBC is SUPPOSED to do. If I wanted 10psi, I would be complaining that I have to tune for 8 and set the overboost at 13. If EBC weren't useless (title of the thread...) then I could set the EBC for 12psi, overboost for 13psi and drive the shit out of it always.

Braineack 11-11-2008 04:25 PM

well the problem is, the way overboost reacts.

even if your werent going to overboost, it may trigger. In the cold your spool faster and it "thinks" you are going to overshoot it, so it cuts fuel. Raise the overboost, like 3-4psi above your target, it should always be this way. Else if you go up a hill you'll trigger that shit. Second, tune the cells to slightly slow the ramp rates, instead of spooling with the valve 100% closed, try to allow it to leak a touch as you spool...

cjernigan 11-11-2008 05:05 PM

Oh well, i dont care much, my boost fluctuates no more than 2 psi so setting my overboost to a stupid high level is fine with me. I have the injector for 18 psi and its tuned fine up there. It'll never get cold enough to make it jump that high though. Not here in TN anyway.

akaryrye 11-11-2008 06:56 PM

i wonder how much the external wastegate helps?

evank 11-11-2008 07:07 PM

I've been pondering these same issues. There should be a way to easily set boost targets based on temps.

paul 11-11-2008 07:18 PM


Originally Posted by cjernigan (Post 329212)
I don't see why you guys have issues. I hit 14 psi when its 40* out and 12 psi when its 80* out. My overboost is set at 18 and I tuned for 13 psi at 60*. Pansy whiners.
Maybe you should insulate your EBC solenoid with some thermal wrap and tuck it close to your engine somewhere so that by the time you can get into boost and your engine is warm your solenoid is warm too and you won't be overboosting like crazy. The thermal wrap is just to protect it from overheating.

14 cold/12 hot is not OK with me. Some us want it to make 14 when it's cold and 14 when it's hot. Is that too much to ask?

patsmx5 11-11-2008 07:32 PM


Originally Posted by paul (Post 329316)
14 cold/12 hot is not OK with me. Some us want it to make 14 when it's cold and 14 when it's hot. Is that too much to ask?

For real. And Chad the temp of the solenoid isn't what causes the problems. It's the temperature (read, density) of the air going into the engine. EBC opens the wastegate X percent, but since the mass flow going in is greater at colder temps, and the wastegate doesn't open more to compensate, then more exhaust goes through the turbine, and you get more boost.

MS's EBC is not too impressive to me. MS has the potential to make it badass though. Wish they would. Boost by TPS is the best thing I would imagine, but having boost vary w/ temperature would suck. I'll be putting a MBC in the cabin on my 99' so I can play with boost and adjust if it's cold.

In all seriousness, something as simple as a correction table for temperature would help a ton. Something that scales the numbers X% or something with Y temperature. Still fails in comparison to closed loop, but it would allow you to tune boost to be whatever you want at different temps. (IE, you could have it run less boost when cold to make the same power, or same boost all the time, etc)

cardriverx 11-11-2008 08:48 PM

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EBC problems

Chime in on this thread guys, maybe we can get some good code written....


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patsmx5 11-11-2008 08:51 PM


Originally Posted by cardriverx (Post 329364)
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https://www.miataturbo.net/forum/t28001/#post329330

Chime in on this thread guys, maybe we can get some good code written....


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