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Is ms sequential


wax

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My feeble mind doesn't understand your question.

Thanks for your honesty, its the first step

 

You were impling that sequential was not a major feature worth worrying about

I was saying what is the feature that mega squirt has that would make me buy it over another ecu that has sequential.

If i was driving around at 100% throttle all the time then i would save money and go for a batch fire , but the reality is no one actually does that

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You were impling that sequential was not a major feature worth worrying about

 

Not quite what I said. Placing a major portion of your priorities on *any* single feature may not be the wisest choice. That's a bit closer to my intentions.

 

I was saying what is the feature that mega squirt has that would make me buy it over another ecu that has sequential.

 

Price, support, installation complexities, consistency, reliability, compatibility, software intuitivity (is that a word?), etc, etc, etc, blah, blah, blah, etc, etc, etc, etc.

 

My point is simply, basing a decision on *a feature or two* is not something I would recommend.

 

If i was driving around at 100% throttle all the time then i would save money and go for a batch fire , but the reality is no one actually does that

 

 

Point taken. Driveability is a consideration for me, as well. Everyday driveability is not limited to sequential this-or-that. Sequential may be a contributing factor but it's not *THE* contributing factor.

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What i am looking for is an ecu that has sequential cababilty

All the high end ones have it now . sure its not the only factor but you can get better driveability with it than with out it.

My decision will be based on more than one feature of course , but an ecu that doesnt do sequential is not in my future.

 

If you just after peak numbers then there is no need to go for sequential

But if you want a better idle , better fuel economy and traffic driveabilty then its for you

Surely the fact that all manufactuers have gone to sequential as well as professional motorsport shows it has some merit

 

Have a look at this link

http://www.efi101.com/forum/viewtopic.php?t=3877&view=previous&sid=1eaf7e9e61336048be157f17d6df2b56

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Yeah i am aware of that

The low end midrange is what you pick up with sequential easily.

No i am not going to do the one temp sensor per cylinder as its to hard and expensive( though i could just egt it ).

Going for 6 wide band sensors would just kill me.

I just want the driveablity and the economy that comes from sequential.

 

 

If you're not willing to put the goodies on there, then the 'benefit' for sequential injection will hardly justify the costs involved just so you have bragging rights.

 

We have polytropic head control on our compressors, NOBODY uses it save for people with purchasing departments with geek engineers who cream over the 1% cost savings in electricity they get and somehow convince beancounters that the 3X cost of the system is peanuts when your electrical bill is $1,000,000 a month. The sensro package takes a standard controller from around a $20K retrofit cost, to closer to $65K, individual inlet and outlet pressure sensors, temperature monitors into and out of each stage.... For that they may see a 1% better performance against the surge line when turned down.

 

For a customer running off the surge line, the costs over the $20K system would never be noticed, nor costs recovered.

 

Same with Sequential Injection. Look at what your Motec is going to cost you for even a 'rudimentary' sequential setup.

 

Then realize that economy might (and that's an iffy 'might') net you 1-2% better economy. Meaning you get what 10.2L/100Km versus 10L/100Km? For an extra $2000, you can buy a lot of petrol!

 

If you're basing it on 'better drivability' how do you actually quantify that? If you are unwilling to spend the $$$ for the full sequential package, how will you find the $$$ for the 50 or so hours of rolling road time to flatten out those nits in the road which make the car buck slightly when you decelerate or the hesitant millisecond long snif you get on transition when you flatfoot the car around a right hander uphill whilst looking to the east and winking with one eye? The things don't tune themselves (well, Autronic aside...) but really IMO the Autronic with the OEM style long and short term fuel trim will perform more useful functions set up as a batch-fire unit than ANY other Sequential system that you have to manually chart and configure.

 

The OEM's have nice stable long and short term fuel tuning loops. If I were to buy a high-dollar unit (Standalone ECU) to replace my Megasquirt, I would look FIRST for that kind of automatic fuel trimming, than for 'sequential injection'...

 

The usability of the box is determined by it's user friendliness. Learning to tune simple batch fire can be a load for many people. Add phasing of the injectors, individual fuel trim, and other items that can be engineered to insignificance early on in the project...and it comes down to which is the easiest to set up and do what I want it to do.

 

And figuring out what you want it to do has to do more with concrete numbers and performance figures than marketing buzzwords and phrases subject to purely subjective analysis.

 

Manufacturers went to sequential as a result of EMISSIONS REQUIREMENTS and nothing more. Until recently the processor speeds were not able to be clocked to control sequential over basic idle and low speed operations. Now that processor speed and processor cost has come down it makes fully sequential systems on OEM setups possible, and again with tightening requirements for governmental compliance REQUIRING individual cylinder fuel control and diagnostic capabilities it's not their CHOICE that they are using fully sequential.

 

Where emissions are not a concern, you will still find simple, durable, slow clock speed batch fired systems are the system of choice because they operate with a couple of durable sensors and are rock-solid reliable now that there is over 40 years+ of history ironing the bugs out of them.

 

Lot of talk about 100K mile warranties and all from the marketing department, and it really makes you think the car companies are competing to sell you a better product... but in the USA at least, it's all government mandated emissions compliance that has driven a 100K mile durability certification process. Marketing just found a way to sell you something that they had to put into the cars ANYWAY.

 

Just like Sequential Injection!

 

Think of it like this: Even in F1, sequential injection is nothing more than digital electronics controlling an analog device, the fuel injector. It's not open or closed. There is a non-linear distribution of fuel from that injector. And at higher rpms it can be pretty messy. No matter what you do you still have analog fuel delivery. Until injection technology improves the performance of the injectors, the best you will hope for is a compromise between 'least messy' alternatives.

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Wow a massive answer there

You assume I have no idea what I am talking about and im just sprouting words I have found on the internet.

I’m glad you’re happy with your Mega squirt

Please don’t suppose to know what my income is and if I can afford a decent ecu or not.

The fact is you get better driveability with sequential and thats what i am after

This was never meant to be a Geek off about injection i just wanted an answer to my question

I guess the answer is not yet

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Just to put it here so no-one has to read it elsewhere, MSII_Extra has an Alpha version of the code out that has full sequential injection for up to 4 cylinders and semi-sequential for more than that (6-8).

 

It allows you to time exactly WHERE in the cycle that the squirts occur (timing) and a few that run large injectors on turbo cars have lauded the change as dramatic vs the bank firing scheme that they had to use up 'til now.

 

MSII_Extra already has fully sequential ignition for up to 6 cylinders.

 

THe only requirement at this point for semi sequential is more injector drivers and some slight modification to the MS board itself.

 

I personally will be using the author of the code's peak and hold injector boards in my setup (550cc SARD injectors on my L28ET).

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Guest Rolling Parts

"The fact is you get better driveability with sequential and thats what i am after"

 

Won't you also need an infinitely granular ignition system as well? A better valve train?

Just curious how far you're planning to push for Camry-like smoothness from the old L28. I'd be curious how it turns out.

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the problem with l28 vs modern engines is the cylinder head 2 valves vs 4.the only way to make up for this is by more cam shaft duration-and losing drivability.but at a 14.5 af on the freeway i have seen 26 mpg.more could be had with a 6th gear.sequential might make slightly more-but on a hobby car driven on weekends it would take years for a full cost recovery.a question relating to sequential injection-would it be better to boil the fuel into a smokey vapor by by squirting on to the back of a closed intake valve -or injecting during an open intake valve?

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Guest Rolling Parts
Yeah i am aware of that

The low end midrange is what you pick up with sequential easily.

No i am not going to do the one temp sensor per cylinder as its to hard and expensive( though i could just egt it ).

Going for 6 wide band sensors would just kill me.

I just want the driveablity and the economy that comes from sequential.

 

As Tony said, the real reason for sequential was ever tighter emission standards. The modern engines do the miracle of high HP with smooth power curves not so much with sequential fuel injection at all, but with computer controlled solenoids controlling 4 valves per cylinder, cylinder head design optimization, and serious attention to reducing parasitic drag in the entire drive line. The 370Z (VQ37HVR) is a marvel at this and puts down the power range your interested in with almost electric motor smoothness.

 

On the "let's keep it real here" side for cost effective on the old L28 engine you might want to read up on the MegaManual at: http://www.megamanual.com/index.html The second question there defines what's obtainable with different injector techniques when adapted/grafted onto older engine designs.

 

They also mention their "MS-II Sequencer" and they give a write-up at: http://www.megamanual.com/seq/index.htm If it's anything like their MSII product then it will deliver all the control you need at the lowest cost in creation.

 

Good luck with it. It'd be interesting to see which system you choose and have a datapoint on the L28et to see if sequential actually makes a measurable difference over multi-port alternating batch fire of 2 pairs of 3 injectors (I'm running that on MSII/L28et with distributorless wasted spark ignition (EDIS-6) and it's really smooth).

Edited by Rolling Parts
clarity
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Guest Rolling Parts

The answer the immediate question is No, MegaSquirt is not prime time 6 port sequential.

 

The thing that kept me up all last night (looking at a turbo head on the bench and a bare F54 block on a stand) is trying to reason through the mechanics of just how to get the analog injectors timed to "squirt through" an open intake port. This morning I was reading the comparisons done by smarter people with more experience:

http://www.sdsefi.com/techseq.htm

http://members.rennlist.org/951_race...atchFiring.pdf

 

To me, there is not that much difference to be seen in our old engines no matter which you use because of the the physical limits of trying to precisely "squirt through" a tiny narrow gap in an intake valve with something that basically quirts in a "fan" pattern. No matter what you do you, most of the injected squirt is still going to be aimed right at the backside of the intake valve every time you inject fuel. The slower the air velocity, the more the fuel stream will tend to hit the backside of the valve on it's way into the cylinder.

 

I don't see a way around the basic geometry of the engine/head nor the problem of getting enough fuel quantity delivered ONLY during an open valve event at speed. The only way to get around the very limited dimensions presented by a valve and very limited time of the intake valve is actually open is to not even try. Than means the engine designer will have to:

1) Accept Batch fired multi-port injection as "good enough" or

2) inject the fuel further away from the valve into the incoming air volume (that will be entering during that duty cycle) in the most dispersive pattern (against the flow?) or

3)Do a direct injector (GDI) into the cylinder itself and bypass the messy business associated with the limits presented by getting through a flat valve.

 

I'm not smart enough or have the money enough to do #2 or #3. For people that do then get beyond the idea of sequential and look at the whole picture for a better solution.

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wax, if anyone has an attitude in this thread it is you.

 

I am running a fully sequential setup (yes, fuel and spark) as is RTz. We are both using the same EMS. I bought mine from RTz as he is a licensed distributor for them. As a matter of fact, there is even a sub-forum for the EMS we use.

 

Saying that, unless you TUNE for full sequential, you are not utilizing it. It will not offer better driveability unless you TUNE for it.

 

Am I utilizing the full sequential setup? To a degree, but I have not tuned each cylinder. I am simply pulling timing in 5 and 6 to account for their tendency to detonate first due to cooling deficiencies.

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Thanks

Yes thats what i am planning to do

I have been in contact with autronic , haltech and vipec

Autronic are a good system and have good back up

Haltech are good as well but dont have all the features of the others

Vipec looks awesome , its a new system and i am a bit unsure on there customer support at the moment

They all come in at about 2000 aussie dollars

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Wolf is a great ems. Other programs have issues with Vista. Wolf works fine with XP. I'll have to try it out on Vista though.

 

If you post some questions in the Wolf forum we'll be happy to answer them.

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Like I mentioned, I like the Auto-Tune feature of the Autronic. It incorporates a lot of OEM-Style Technology.

 

Frankly, if someone were to have a GM OEM ECU and that software (like Tunercat) it would be as robust as many of the Aftermarket ECU's available, the fuel trim makes for great drivability on your particular car--- the difference between the Autronic and a GM ECU with long term and short term fuel trim is the ability to incorporate the Long Term and Short Term Fuel Trim into the basic map permanently with a keystroke. On the GM's you store it in RAM which is volatile, and when you disconnect power to the ECU it looses it, and starts learning all over.

 

I would NOT be in a hurry to buy an EMS system. The Self-Tune technology is progressing QUICKLY in the aftermarket. Autronic makes the second manufacturer that I know of that has incorporated the OEM style trim as an option for talioring the Mapping of the ECU.

 

There will be only more of this in the coming year or two. Turbocharger technology is static for the time being, same as head and intake technology. Those are something you can do now that you will not have a surprise in a 'great leap forward technologically' within the next month, or even year of construction.

 

Frankly, if building an engine, I'd buy the EMS system last, after it was all asssembled or close to it. Some of these assemblies can take years when other things get involved. The last thing you want is a smokin' brand new, never been in the car, ready for action Second Group Buy MS-1 sitting in your shed waiting for installation 7 years later when you get the time to put the car on the road (speaking from experience, I now have one in a car and 'two fully operational spares'...)

 

The next one will have either Autronic, or another box produced locally here in SoCal by a group of guys in Corona. Yeah, it's $1200, but I understand and trust the Fuel Trim functions as I have investigated them. It's truly OEM technology, and makes for a great driving car...quickly!

 

As for big injectors and poor drivability...the type of injector can be as important as the size in drivability. JeffP had crap idle with some 600CC units, but ended up going with 720's which idled as good as his 450's did years ago. Latency, opening and closing speed, can radically effect the idle quality. It it's not a quick switch, and they dribble or are sluggish, idle can go down the tubes quickly! It's not just the size.

 

I'm not going for mongo-horsepower where I would need anything over 450 or 550 CC's in a street car, so I wouldn't really be concerned with sequential in my application. If you were planning on 500+ and running 700CC+ injectors, I might agree that sequential might clean up the idle depending on the injectors used...but even then 'semi-sequential' is probably all that is needed. By boost threshold (say 3500) you will want to swap over to batch and start laying on the fuel for power.

 

I digress...

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