409whp Yay

[Maxx Mazda]

When I'm getting my car tuned using my Split Second AFC, I'm gonan do it based on AFR of course, and once tuned will go with the J&S. I just think that trying to tune, with the J&S pulling and advanceing timing would be a nightmare...

 

[yashooa]

The day I "accidentally" smacked down an, at least, 20PSI+ run I was so very, very, very, very, glad to have a J&S in there.
Worth every, damn, dime (first)

 

[Kansei]

split-second AFC + J&S + stock p5 ecu?

 

[LinuxRacr]

When I'm getting my car tuned using my Split Second AFC, I'm gonan do it based on AFR of course, and once tuned will go with the J&S. I just think that trying to tune, with the J&S pulling and advanceing timing would be a nightmare...

The J&S only pulls when it senses knock. You can turn off the auto pulling feature that pulls when no knock is present.

 

[Ddrop]

The J&S only pulls when it senses knock. You can turn off the auto pulling feature that pulls when no knock is present.

Again im not seeing much of a difference between that and a megasquirt or other strandalone setup tht uses that feature (especially with megasquirt software being programmible). only benefit i see is that itll let you run closer to the edge of detonation with its "special algorithm" ...which id rather not do neways. JGS looks like a great unit for piggyback/fmu setup, but id still prefer my megasquirt full standalone system...especially in the price vs performance area.

 

[Brian MP5T]

Unreal

 

[Blackrose]

OK dude. Megasquirt is the greatest EMS on the planet, now we all understand. If there are 10 people here telling you its the best and you are the only one not getting the hint then either

A Get a clue

B dont listen to us and do what you want

C listen to us and do what you want

It has been explained several different ways. Like I said not even superman can tune a cars timming in anticipation of detonation. Its not hummanly posible. There has been not one instance of a protege with this unit on that has blown there motor as far as I know. There have been plenty of people with all kinds of different types of EMS's on there cars that have. And as far as the detonation detection in these EMS systems. They are shotty at best. Even top of the line standalones can do what the J and S does. But you seem to think the unit is pointless so have a nice day. Have fun and good luck.

Again im not seeing much of a difference between that and a megasquirt or other strandalone setup tht uses that feature (especially with megasquirt software being programmible). only benefit i see is that itll let you run closer to the edge of detonation with its "special algorithm" ...which id rather not do neways. JGS looks like a great unit for piggyback/fmu setup, but id still prefer my megasquirt full standalone system...especially in the price vs performance area.

 

[igdrasil]

When I'm getting my car tuned using my Split Second AFC, I'm gonan do it based on AFR of course, and once tuned will go with the J&S. I just think that trying to tune, with the J&S pulling and advanceing timing would be a nightmare...

Yeah its good to have it retarded all the way, say like 12 total advance and tune A/F. Timing should be safe for up to 15psi on 93octane. Install J&S and start advancing until you dont gain HP and you are done.

A/F may start to lean out a bit, but if you set it to low 11s you will nail it.

 

[Ddrop]

Umm when did I say it was useless? I first suggested megasquirt as a cheap alternative to a piggyback/jgs system and got blasted saying jgs is so much better. Im sorry im intrested on how it compaires to other knock detection systems after hearing that. Im sorry that im looking for answers other then "its just better". Im sorry I question why its so popular here and not so much on other forums. I understand its a great system and is deff worth the money if you have no knock detection system...no doubt about that. im just trying to find out if/why its worth getting when you do already have a similar knock detection/prevention in ur ems.

 

[Blackrose]

Because like already stated several times. The knock detection systems in these EMS's are half ass. They are in most cases no better then stock detonation prevention.

J and S can retard up to 20 Degrees of timing. The best ems's are 8 at the most.

J and S can retard on a cylinder by cylinder basis. I dont think any of the EMS's for the protege can do this.

J and S gives you the option to monitor the system so you know exactly when the detonation occured. Most EMS systems do not have this option and only a handful will alow you to data log the knock sensor.

Easy to use boost controled protection and adjustible sensitivity.



It is on the fly protection. Sure you can alter your maps on the ems for weather changes. But with the j and s you dont have to.

The point is that an EMS is designed mostly for fuel control and in some cases timing control. When it comes to protection via knock sensor they are seriously lacking. This unit was designed to be then end all unit for kncok protection period. There are other minor advanteages to the unit but ill just leave it at this for now.

Umm when did I say it was useless? I first suggested megasquirt as a cheap alternative to a piggyback/jgs system and got blasted saying jgs is so much better. Im sorry im intrested on how it compaires to other knock detection systems after hearing that. Im sorry that im looking for answers other then "its just better". Im sorry I question why its so popular here and not so much on other forums. I understand its a great system and is deff worth the money if you have no knock detection system...no doubt about that. im just trying to find out if/why its worth getting when you do already have a similar knock detection/prevention in ur ems.

 

[Blackrose]

BTW im not saying that the prevention systems in place on some of these EMS's are not anygood. The reason I got defensive ofrom what you said is its kinda misleading. You made it sound like the megasquirt can do the same as the J and S. They are not close. Someone reading this thread that doesnt know anything about these different units could make a bad call on what they want based on misinformation.

 

[Ddrop]

that was the answer i was looking for. thanks :tup:

 

[TurfBurn]

Again im not seeing much of a difference between that and a megasquirt or other strandalone setup tht uses that feature (especially with megasquirt software being programmible). only benefit i see is that itll let you run closer to the edge of detonation with its "special algorithm" ...which id rather not do neways. JGS looks like a great unit for piggyback/fmu setup, but id still prefer my megasquirt full standalone system...especially in the price vs performance area.

Last guy that said that had his motor blow up and he sold off the car... soooo....

 

[TurfBurn]

The other problem that I didn't see in Blackrose's comments was the fact that you have to "set" your own knock levels with the EMS's... so unless you can guess right etc you won't have ANY knock protection with your EMS.

John has a link that can show you a head to head of his system versus the AEM's system and you'll see clear as day what we are talking about then.

Thanks,

Steve

 

[TurfBurn]

Okay, I re-read all the comments and what was going on..

here is the low down on what you need to know etc:

Most EMS's are setup to be able to retard some fixed degrees when "knock" occurs... it doesn't vary etc... just one or two thresholds... basically if it hears knock it pulls say 5 degrees on all cylinders. Then some have a second threshold where if you STILL here knock you pull another 5 degrees on all cylidners and it stays there until it meets certain other changes/conditions etc.

The condition used to typically decide whether or not knock is occuring is a noise level/threshold detected by the knock sensor which is basically a bandpass microphone. So you have to set thresholds based on engine load and rpm's (if the EMS is that sophisticated) and you will have to find out/guess what those are... if they are exceeded it pulls the timing, if not it doesn't do anything... so unless you set those right you'll either pull it far too often, or not pull it when it matters.

So that is basically what happens with pretty much any EMS... and the long story is basically that it isn't all that effective.. yes it is better than nothing, but it is typically not safe.

The J&S on the other hand has specific algorithms that can pay attention to a very specific window of the crank angle to detect when the knock will occur, and has algorithms to determine what is engine noise and what is not AND re-calibrate on the fly to cancel out the changes. So on top of that... it pulls a few degrees of timing, listens on the next rev, pulls more if necessary, listens again, and adds the timing back if everything is okay... all in real time and all on individual cylinders. Add this to the fact that it detects knock at such incredibly low levels you can't even hear them using amplified listening devices (trust me, I've tried). It also is fantastic on the dyno as we could see everything clear as day... push timing push timing get more power... push too far and the J&S pulled the timing and we still held max power...

That's the short version... let me know if you want more detail.

Later!

Steve

 

[sanblaster]

You da man Steve.

 

[Kansei]

this thread really makes me want the J&S.. I just wonder if with the dsm afc doing fuel and the J&S doing timing, could I go back to my Protege5 ecu instead of my really moody and PMSy unflashed MSP ecu?

 

[igdrasil]

Nice combo here: http://www.promax.uku.co.uk/wolf3d.htm

 

[LinuxRacr]

I wish I still had my J&S. Hmmm....

 

[Maxx Mazda]

So I read somewhere the DSM AFC tops out at 15 psi. Anyone else heard of this? If so, I need new EMS...