DSM chip or SAFCII

[Midnightride]

Ok pretty much im in a depate. Either spend the money and get a SAFCII or I was looking into getting a DSMCHIP stage 3 probably.

Here is what im working with.

14B ported,exhaust manifold ported,o2 housing ported,3"turbo back exhaust w/high flow cat, MBC,FMIC w/hard piping,crushed 1G BOV, removed emissions stuff in engine compartment, K&N filter.

I have 550's and a 190 denso pump waiting to go in as soon as I get either of the above. Looking to run 20psi on pump gas.

I guess with having the SAFC I would have more room to tune VS. just having a chip.

Give me your thoughts please.

 

[delta448]

Get the SAFC. Then get the chip whenever you can. The chip will get you closer to the right timing map, but you'll probably be able to pull off a better tune, if you can only get one of them, with just the SAFC first.

 

[Batman™]

I bought an safc for tuning, but then I was convinced to do the chip. Without going into too much detail, the odds are overwhelmingly in the chip's favor, and you'll never need to tune with one. You tune on a chip through upping the boost basically. Timing won't be an issue. If you're really in the dark on it, I suggest you talk to Andymoraitis. He's a wiseman on here that can really clear things up for you.

 

[JayRolla]

If you burn the ECU you really dont need a safc. You can burn a custom 11:1 fuel map on it and custom timing maps that peak around 12-16*. You should beable to get 20psi easy out of that. Now if you put in race gas you can use a safc to lean out the mixture but other than that you wouldnt need a safc at all with a burned ECU, which is the best way to go.

 

[andymoraitis]

Well, you can still tune with one but you'll be using boost, octane and fuel pressure as tuning tools.

The main deficiency with the AFC is that it lies to the ECU about incoming airflow so that it can compensate for larger injectors. The issue with this is that as the injectors get larger the compensation to make them work like stock 450's makes a mess of the timing maps. Why, you ask? It's simple. When the ECU sees less airflow, it doesn't reference the highest load map. The high load maps actually limit timing on a 2G to 16 degrees advance. If you compensated for 650's, you would be subtracting enough airflow to correct for the injectors such that the timing would keep going past 16 and likely end up around 22-23 degrees (or more).

The issue with high timing on pump gas is that it's lowers your ability to control knock. As such, you have to reduce boost to keep from knocking excessively and as a general rule boost makes more power than timing on pump gas. So you'll end up in a constant tail chase between airflow subtraction, boost and timing and will never quite get to an optimal tune.

The difference with a custom Keydiver Chip is that the air fuel ratio is locked in as well as the timing. So let's say for example that on an AFC you could run 18 psi on 22 degrees of advance with 93 in the tank. On a Keydiver chip with locked timing maps you could run 23-24 psi with 16 degrees of advance. While this is just a generalization and should not be taken as a concrete written in stone example because a great deal depends on the setup, it provides a worthwhile illustration as to the limitations of the AFC. Much of what you can do on pump gas is dependent on air intake temps, compression and a host of other factors like compressor efficiency but you get the general idea.

If you were to look at my profile, you'd notice the absence of anything other than an EPROM ECU with a custom chip to control A/F, injector compensation and timing. At 51 lbs/min of airflow I see upwards of 510 ponies at the crank and that's nothing to sneeze at. I can still tune with boost, octane and fuel pressure if need be to get the motor to a point at which I've optimized my setup.

That being said, compensating for 550's on an AFC isn't all that bad in terms of what it does to timing but should you ever choose to run a larger turbo and larger injectors you'll hit the tailchase I alluded to very quickly. Let me close by saying that I could give a fat rat's ass how much power people have made on an AFC. I'll always see it as trying to hammer a nail with a tree stump.

Let me know if that makes sense,

Andy

 

[andymoraitis]

If you burn the ECU you really dont need a safc. You can burn a custom 11:1 fuel map on it and custom timing maps that peak around 12-16*. You should beable to get 20psi easy out of that. Now if you put in race gas you can use a safc to lean out the mixture but other than that you wouldnt need a safc at all with a burned ECU, which is the best way to go.

Just to clear something up, NEVER take stock internals below 14 degrees of advance. The extra heat brought on by lower timing will weaken cast parts exponentially and can cause premature failure over an extended period of time.

In general I recommend a peak of 16 degrees for 2G's running pump gas and around 18 degrees (depending on motor setup) for 1G's running pump gas. Also, you can have Jeff make two maps in the chip and toggle between them (dual image mapping). There's no need for an AFC on race gas.

Everything else looks fine Jason.

 

[JayRolla]

Sweet andy, how does that two maps on one chip work. Does he give you a program on a laptop to change it or what.

So never take a stock motor below 12*. I never knew that either. Man I learn way to much from you Andy. Naturally you would think the lower timing would be less strain on the motor but I guess im wrong.

The only reason im going with a SAFC instead of a burned ECU right now is because I want to learn how to use it. Its mainly a learning experience for me. I will be getting a custom burned chip after I play around with the SAFC. Or maybe dsmlink after that.

 

[DGajre777]

Here is some more info on dual image mapping. http://www.dsmchips.com/dualimage.html

And don't forget you get to see knock sum on your factory boost gauge with a chip, and get a stutterbox, something an SAFC can't do.

 

[JayRolla]

That is pretty bad ass. I think im going to have to go out and get an eprom. One question wouldnt you beable to make more power on a dyno tuning the A/F ratio with dsmlink. Also tuning the maps then just tuning the boost, ect to the ECU since all cars are different.

 

[andymoraitis]

Jason,

Lower timing naturally makes a bunch more heat. For example if someone tried to run what I run (8 degrees peak) on cast parts it would trash stuff after a period of time.

I considered dual mapping but since I plan on keeping this car as a pump gas monster I passed. I'd like to make the same power at the track that I would on any other day of the week. Besides I'm out of boost on this setup so the only think left is to add a bit of timing back in and I think can get away with that just fine on 100 octane.

The only downside to the chipped setup is that the settings are fixed. You could lean out a bit more and bump some timing with an AFC of MAFT and a chip, but that's expensive enough to make DSM Link worth it. Chip tuning is something you get a feel for. I've run close to 30 custom chips before finding the right combination of settings that gives me the results I want. For most people it's just easier to buy Link but Jeff and I enjoy trying new things and learning what works and what doesn't that way we can pass on the information to others without having them go through the same trial and error.

 

[DGajre777]

That is pretty bad ass. I think im going to have to go out and get an eprom. One question wouldnt you beable to make more power on a dyno tuning the A/F ratio with dsmlink. Also tuning the maps then just tuning the boost, ect to the ECU since all cars are different.

The power difference with 11:1 A/F ratio or 11.5:1 A/R ratio is almost the same, as in there is not that much difference. DSMLink is a higher setup that a chip because it gives you the ability to change everything right there. With a chip, if you want to change the A/R ratio, timing, rev limit, fuel maps, etc, you'll have to send it in and have it changed (unless you buy a chip burning program and software and do it yourself at home).

So if your goal is to have 11:1 A/F and 16 degrees of timing, you can have a chip burned for it OR you can get DSMLink, hook up a wideband and fine tune it. Either way the final output will be the same.

As long as you have a good AFPR which raises fuel pressure on a 1:1 ratio to boost, the maps will stay the same.

 

[andymoraitis]

The power difference with 11:1 A/F ratio or 11.5:1 A/R ratio is almost the same, as in there is not that much difference. DSMLink is a higher setup that a chip because it gives you the ability to change everything right there. With a chip, if you want to change the A/R ratio, timing, rev limit, fuel maps, etc, you'll have to send it in and have it changed (unless you buy a chip burning program and software and do it yourself at home).

So if your goal is to have 11:1 A/F and 16 degrees of timing, you can have a chip burned for it OR you can get DSMLink, hook up a wideband and fine tune it. Either way the final output will be the same.

As long as you have a good AFPR which raises fuel pressure on a 1:1 ratio to boost, the maps will stay the same.

Nicely said Dee. A/F (to a point) is not as influential as boost or timing. You'll see a big difference going from 9.5:1 to 11:1 but the difference will be more marginal when going from 11:1 to 11.5:1.

I'd like for everyone to also consider that the size of your turbo and it's efficiency on pump gas will dictate the chip settings I'd recommend. For example, there's only a certain amount of boost someone can make on a 14B so for that setup I'd recommend a bit more timing and slightly less boost to keep the air intake temps lower. On something a bit larger like an EVO III, I'd do the opposite and set the tune for around 24 psi on pump with lower timing.

If you looked at my airflow on a compressor map overlay, you'd see that at a PR of 2.9 and 51 lbs/min I'm off the map. Since I really like this turbo and don't want something larger at the moment my best option is to leave the boost alone and maximize timing to bring the whole equation together. If I had a turbo that was more efficient at higher boost, like a 60-1, I'd keep the timing the same and add more boost. It's very simplistic but I always approach a tune by looking at the limiting factors and then playing to whatever strengths in the setup I can.

 

[sureshot971]

This may be a stupid question, but how do i tell if my 95 gst has a eprom or not? The person who sold me it says it did but i want to make sure.

 

[andymoraitis]

The ECU is buried underneath the stereo. Remove both kick panels and you'll see it wedged in. It's held in by a number of 10mm screws that'll need to be removed and you'll have to bend the driver's side bracket slightly to extricate it. Make sure you take it out from the driver's side by the way.

Once you have it out, look for an "E" in the serial number or you can disconnect it from the wiring harness and open it up. If you held it so that the connectors were pointing directly away from you, you should see a chip soldered into the board on the bottom right.

Let us know what you find and keep your fingers crossed. It's great when you have one since that saves the cost of having to buy another ECU.

 

[sureshot971]

Yea i will go check that out right now, so it will just be a E anywhere in the serial number?

 

[andymoraitis]

Yea i will go check that out right now, so it will just be a E anywhere in the serial number?

Here's an easy way to tell once you've pulled it:

http://www.dsmlink.com/faq-eprom.html

 

[DGajre777]

Yea i will go check that out right now, so it will just be a E anywhere in the serial number?

Here you go - http://www.dsmlink.com/faq-eprom.html

 

[andymoraitis]

Here you go - http://www.dsmlink.com/faq-eprom.html

Come on Dee. My Kung Fu is faster than your Kung Fu (at least today).

 

[DGajre777]

Come on Dee. My Kung Fu is faster than your Kung Fu (at least today).

Hai Sensei.

 

[sureshot971]

Congrats to myself, it is indeed an eprom

 

[delta448]

Well, you can still tune with one but you'll be using boost, octane and fuel pressure as tuning tools.

The main deficiency with the AFC is that it lies to the ECU about incoming airflow so that it can compensate for larger injectors. The issue with this is that as the injectors get larger the compensation to make them work like stock 450's makes a mess of the timing maps. Why, you ask? It's simple. When the ECU sees less airflow, it doesn't reference the highest load map. The high load maps actually limit timing on a 2G to 16 degrees advance. If you compensated for 650's, you would be subtracting enough airflow to correct for the injectors such that the timing would keep going past 16 and likely end up around 22-23 degrees (or more).

He's got 550's right now, so timing might be slightly aggressive, but isn't timing also fairly weak on 2G cars to begin with? I really don't care for the SAFC any more than you do, but I think in his case the SAFC might be better suited. I think there'd be a better chance for a bullseye on the tune.

The difference with a custom Keydiver Chip is that the air fuel ratio is locked in as well as the timing. So let's say for example that on an AFC you could run 18 psi on 22 degrees of advance with 93 in the tank. On a Keydiver chip with locked timing maps you could run 23-24 psi with 16 degrees of advance. While this is just a generalization and should not be taken as a concrete written in stone example because a great deal depends on the setup, it provides a worthwhile illustration as to the limitations of the AFC. Much of what you can do on pump gas is dependent on air intake temps, compression and a host of other factors like compressor efficiency but you get the general idea.

The thing that keeps me from going with a chip is the fact that it is not adjustable. Also, you really only are left with basic injector correction when in open loop mode. AFR only gets controlled when the ECU is in closed loop, or under something like 40% throttle. I would think the AFR would be hard to nail because different brands of injectors have so much variance. But, like Dee said, boost and timing make more of a difference after you get in the right zip-code of optimal AFR.

If you were to look at my profile, you'd notice the absence of anything other than an EPROM ECU with a custom chip to control A/F, injector compensation and timing. At 51 lbs/min of airflow I see upwards of 510 ponies at the crank and that's nothing to sneeze at. I can still tune with boost, octane and fuel pressure if need be to get the motor to a point at which I've optimized my setup.

Andy, your car is a can of whoopass just waiting for a victim. I have the utmost respect for you and all you've done for our community. But with all due respect, I would expect that not too many of us here (let alone a newb, -myself included) have the complete all-around understanding to use boost, octane and FP to tune with.

That being said, compensating for 550's on an AFC isn't all that bad in terms of what it does to timing but should you ever choose to run a larger turbo and larger injectors you'll hit the tailchase I alluded to very quickly. Let me close by saying that I could give a fat rat's ass how much power people have made on an AFC. I'll always see it as trying to hammer a nail with a tree stump.

Let me know if that makes sense,

Andy

I agree with everything you said, I just look at it a little differently. Personally, I think the DSM ECU is a work of art and that the SAFC is a complete hack of a tuning device. That's why I'm saving up for DSMLink. However, I think the SAFC would be better than a chip for a beginner, and when he wants to go with bigger than 550 injectors, that's when he should get the chip. Then he can nail the tune on the chip by using only a slight offset with the SAFC.
http://www.dsmchips.com/tuning.htm

 

[DGajre777]

DSMLink is a better device compared to a chipped ECU. No doubts about it. But now comes the cost. By the time you find an E-Prom ($200) + DSMLink ($600ish) you are running near $800. Add hours of dyno tuning at $70-$100 an hour OR $200 for a wideband and it pushes it near $1000. With a chip and E-Prom you are looking at $350 with the A/F ratio and timing that you want.

Now add the fact that if your battery dies, you have to remember and reset everything on DSMLink since the 2G doesn't have a memory board yet. IF DSMLink comes out with a memory board, no need for an E-PROM ECU, I might think of getting one. Then again, for people who don't want to buy an E-PROM, there is ECUPlus which offers timing and fuel control without a stutterbox. www.ecuplus.com

But with all due respect, I would expect that not too many of us here (let alone a newb, -myself included) have the complete all-around understanding to use boost, octane and FP to tune with.

- I agree. I know a little, not as much as Andy, but... when the chips are burned, they ask for Fuel Octane and Fuel pressure than you plan to run. The timing and fuel maps depend on this. If you see knock you can either a) turn the boost down or b) increase the fuel pressure.

Power is made by using high boost and low timing or low boost and high timing. With a turbo like 16G where you don't expect to run 28 psi, you can use high timing. With a turbo like a GT30 where you can expect to run 28 psi, you can use low timing (not too low on cast, as Andy said above). The tuning you do at 18 psi will be the same for 22 or 28psi. That's what a good AFPR takes care of.


.... Break time is over. Back to writing my 30 page paper on AirTran for my Air Carrier Operations class. Later.

 

[andymoraitis]

Zach,

You raise some very good points (quite nicely I might add) so let me clear up a few things.

Tuning with boost, fuel pressure and octane is not as hard as you might think. As a matter of fact it's very easy once you've gotten yourself close to the targets. Speaking of targets, there's a very wide range in which one can operate and still be safe. A/F from 11-11.5:1 is more than workable on pump gas and there's no need to go higher or lower unless it's a very special tune.

For timing this is even easier. The 2G naturally runs lower timing than our 1G counterparts since the compression ratio is higher. As compression rises the amount of boost and timing you can squeeze in on pump is decreased. 1G's are very forgiving in this regard, hence the aggressive timing map, while 2G's are slightly less so. That's why I'll use a bit more timing for a 1G chip than a 2G. Of the more than 50-60 of these custom settings I've given to people only one took more than one try.

Adjustability is the one of the many things that makes DSM Link excel. However I've done so many consultations and tried so many different combinations that it's extremely rare that I don't hit the mark on the first try. If something's off it's almost never the tune. Keep in mind that Jeff's chips were never designed to be a tuning solution but between my requests and his knowledge, we turned them into one without ever meaning to. I actually have to take very little credit since Jeff is the mastermind behind all of the code that makes these chips work.

I wanted to address one more thing with respect to A/F ratios and such. The A/F ratios that Jeff creates are for OPEN loop (WOT). While I can't be too specific here because I'm out of my league it's my understanding that my settings are fixed across the 4 highest load maps (there's more than one). Therefore it follows that the tune is consistent across those load levels. Again, I would need to ask Jeff how they break down but I know they're in there.

For me it comes down to this. I'm an old Mustang tuner from the mid 90's. I learned everything I needed to know by reading a set of plugs and running a setup on a dyno. We kept things simple and it worked. We didn't fake out the ECU like so many piggybacks do and it worked well. While tuning a turbo car is slightly more complex, I still prefer to keep things simple. Being able to read knock on the stock boost gauge in real time without a standalone is a bonus I can't emphasize. The only time I even hook up a logger is to see what kind of airflow I'm moving.

Really, you're absolutely right. We both are although we're approaching the same issue from a different side of the bridge. An AFC is more than capable of handling 550's and even larger injectors but I just don't feel it's the right way. If there's something better and more simple out there you can bet it'll be my choice. The easier it is to work with the more I'll like it and recommend it to the new tuners out there. It really is plug and play and the feedback I get from people usually emphasizes the phrase "night and day difference".

Thanks for disagreeing with me agreeably. I'll always respect that.

 

[delta448]

Thanks for breaking it down like you two did, ...I'm almost convinced to go the chip route myself. After realizing the price differences, Dee, -and Andy, the bit of info on chipped closed/open loop AFR control, I'm seeing the only possible downfall would be changing injector size. Even then, it's only $100 for a new chip. That makes a huge difference to me. My budget really sucks right now with the new baby boy and all.

 

[MarkAngelo05]

Thanks for breaking it down like you two did, ...I'm almost convinced to go the chip route myself. After realizing the price differences, Dee, -and Andy, the bit of info on chipped closed/open loop AFR control, I'm seeing the only possible downfall would be changing injector size. Even then, it's only $100 for a new chip. That makes a huge difference to me. My budget really sucks right now with the new baby boy and all.

Jeff at dsmchips.com re programs the chip for your for only 20 bux I believe. Personally, if I could do it all over again, I would have gotten his eprom ECU and stage 3 combo for only 350.00 instead of spending money on my AFC NEO.. then after saving more money, buy DSMLINK which is 200.00 more than the safc, but you have virtually complete control over your engine management system. Thats just my oppinion though... I'm enjoying the stage 3 features in my Keydiver chip, wish my trans was good enough for the no lift to shift feature, but i don't wanna blow anything up.. . Anyways, when I finally got my whole ecu setup, My car ran perfectly fine with the AFC settings completely zeroed out.. a lil on the rich side, but Jeff tunes it as close to 11:1 ratio as possible and decent timing curves for your setup.

take care,

Mark