How many cranks to start your turbo engine?
 

I really want a car that starts on the first crank when I turn the key. There is something so satisfying about that. Not sure if I'll ever get it there, but I have gotten the car to start reliably with the Hydra after about three crank cycles of starting (roughly 3 seconds with key turned).

Just curious how everyone else's turbo cars are with starting/cranking and if anyone has gotten it dialed in to start on the first crank?

Cheers!

First time, one second, because even megasquirt ms1 has a setting for a priming pulse. I'm on an ms3 now and it's still just as perfect.

Kick ass and super interesting! What exactly does the priming pulse do? I'll have to dig around in the Hydra and see if there is anything comparable.

Edit: found a description of what it is.
"When the key is on, the MegaSquirt will turn the fuel pump on for 2 seconds and fire one priming pulse to clear air for the lines. (You can disable this feature by setting the priming pulse to zero in most firmware versions.)"

That's awesome. I know there is a setting in the Hydra to turn the fuel pump on when you turn the key. Mine comes on for three seconds, but it doesn't seem to help starting too much.

Squirts a programmed batch of fuel out of each injictor upon Key-on.

Can be delayed for weak fuel pump.
Programmed in mS
Variable according to CLT

So just sit down and turn key to Start. Mine waits 300mS and then injects Priming Pulses (batch). Meanwhile, at about 500mS, sync is obtained and Cranking Pulses begin (sequential) and spark is engaged. Car starts.

If you want, you can pause at “on” and then go to “start”, but it is not necessary.

Sweet, found that Hydra EMS has it too. You guys rock, didn't even know this existed!

Hydra EMS :: Nemesis 2.7 > Manual > Start Primer

LukeG, sorry to rain on your parade, but I think what you are trying to do is impossible with a Hydra ECU. The parameters we access and change with the interface program are system variables. Values that need to be set in the program in the ECU that runs the engine. I'm not knowledgeable on the Hydra or Megasquirt code, but there has to be a section of code that fires the first spark plug after certain parameters have been met. Not all these parameters are variable, changeable by the user. When I was at FM and we were programming the Link ECU, this section of code fired the appropriate spark plug to start the engine after 1/2 crank revolution from 0 RPM. When cranking the engine, if all pre-starting conditions are met, and the crank has turned 1/2 revolution, the ECU would allow the engine to start.

I know the Hydra has always taken a few rotations to start. Versions 2.5 and 2.6 were a little faster, but the 2.7 has always been slow. I speculate that in the starting code in the program the crank must go through 3 or 4 revolutions before all the conditions are met for the engine to start. That's why I make the first statement in my post. We can change all the parameters we want to optimize the starting conditions, but if the code in the ECU wants to see multiple crank revolutions before starting the engine, it will never start any sooner.

Every one of my cars started just as quick and smooth as OEM.
Every one ran on megasquirt and not the archaic piece of garbage that is the Hydra.
Just tuned a 2.6 for a customer recently and still in shock at how bad it is. But then I think it was put together in the 80s/90s? (or at least it better be, if it was put together any more recent, the company deserves to go out of business)

No offense.

Ahh gotcha. No wonder I can't get this damn thing to start any sooner than that. Thanks Ken!

No offense taken!

I agree it is a POS in many ways with zero support (aside from Ken Hill and FM). If I didn't get it for free with the car, I would be using MS all the way! This is just one more reason why the Hydra sucks apparently. I'm in a situation where the car has a great tune on it, runs well and it cost me nothing. I could switch to Megasquirt, but that's going to be a decent amount of work and money. If it wasn't for Ken's help navigating the software, I would have ditched it already.

I thought a longer start time was normal for an aftermarket EMS. Damn you Megasquirt peeps, I'm so jealous of your first crank starts!

No aftermarket ECU I've ever used has started as fast as OEM. Hydra 2.5 wanted to see an entire engine cycle before it would fire an injector (2 crank revolutions). MS3 is faster than that (1 crank rev, maybe?), but it's not as fast as OEM. OEM fires as soon as it gets the first crank pulse.

--Ian

I showed many folks, including E02k my MSM hot start in person (ms3pro id725 batch-fire on cranking) :)
If I'm wrong feel free to correct me :)

If it wasn't identical to OEM, it was so close that it was hard to tell the difference.
Nothing wrong with that. Just enjoy it as is.

Reading through this, it sounds like I am just innept at tuning start up (which is what I expected) since it takes a few turns for mine to start up and settle into an idle....

I am still salty about my friend's car starting in 1 turn the first time after putting the link in...

Stock miata started in like 2-3 revolutions.
my ms3 miata starts same as stock, 2-3 revolutions of the starter.

turbo never seemed to effect the ease or difficulties of starting to me.

Do your miatas really start on the first revolution??

only engine that starts on the very first crank of the key is my riding mower. Lol.

https://cimg2.ibsrv.net/gimg/www.mia...a97123e44e.jpg

200 RPM = 3 rev per second. So a start in one second is 3 rev or 1.5 cycles.

Yes, quite normal.

As I mentioned in another thread, lately I have had some in-consistencies, but the above is quite normal.

But second, not 1/3 of a second.

I’m out of town for a week. When I return, if there is still interest, I can post some logs. For logs to be captured, I turn key to ‘On’ until MS is talking to TS, then ‘Crank’.

My Hydra takes a few cranks as well, even worse now with the new starter (duralast brand, doesn't seem to spin as fast as the old one). Hot starts are quicker in my experience, but I'm sure my cold start fueling isn't spot on or anything.

Could we (I) get a screenshot of your Priming/Cranking Pulse settings? I got the same injectors on my VVT engine with the MS3pro and had a hard time starting the car in cold conditions until I recently changed the Cranking pulse to about double of what I had before..
Starts better now, but I would be interested to see your values to compare...

Shit with the cold starts is, that you always get only one chance to change something...

Thanks! Greets
Sven

Hydra here, old cold start its 4-5 revolutions, hot start maybe 2-3.

sent