I used to have a '72 450 slc... great car!, well except for the rust...

250K miles and would pull like a tank to 6000 rpm...Djet fuel injected...

only thing I did in 3 years was change out the plugs... I think that the car weighed like 4200LBs....heavy...

my wife hated it...called it a guys car..now she loves the bmw....go figure.

There's a difference between these two:

1.) A recommendation that comes from a vendor and goes to a customer. Those need careful consideration because there are significant ramifications for a failed system.

2.) A recommendation among friends. This is what we're talking about here.

MS isn't for everyone, but you can't say it's for no one. Keep in mind that SDS had growing pains, and even the T4 was considered garbage and worthless until someone took the time to figure it out and get it right. MS will get there someday, as long as we don't convince everyone to throw it away.

The real intention of this post was to usderstand why SDS can fuel an engine better than MS. there doesn't seem to be a clear cut answer, other than it's easier to setup. It seems as though they are comparable in their capabilities with SDS being a bit better in the IAT area.

Why is MS considered " experimental".?

Since I have MS I will say , there are some probs. I encounered, not huge but frustrating. There have been very little probs. with the build portion (built it myself) but more with getting answers when there is a prob. .

You do have to rely on the web site and wait for a response. When you are in the middle of a project and not getting a response, it suck's. I am restless and when there is a prob. I want an answer NOW! But there has never been a time when I posted and did not get a response.

MS does have some good features like a soft rev limiter with a timer that when timed out will goes to a hard limiter. Great for AXing.

MAF and MAP blend is avail. through MS. and could be of use on a t4, i've head of someone doing this.

I can see Why Jake would lean twards SDS because of the ease of setup. He is not is the posistion of messing around with settings he does not need.

Being able to setup an engine in 20min. is slick.

I have chatted with people on the MS site that i'm sure can do the same with MS.

Most of us on the otherhand, are hobbiest and building, installing, tuning and playing with different settings is fun and part of the hobbie.

from what I've read in all the posts, it all comes down to choice.

We've started a carb. vs. F.I. style of debate with F.I.

It is experimental because the developers do not want the liability for failures.

No debate, its just another case of different people having different needs. Recognize and respect that and the world is a beautiful place. All is gud.

I do believe that MS has its place and I believe that place is in the hands of those that are more like me.. That said, not many people that buy things from me are like that, most aren't even close. They come to me because they don't want BS and guesswork when buying parts or an engine. They want to bolt it in and drive it away and other than an oil change they want to leave it alone.

There is a reason why the ECU in any modern production car can't easily be tapped into and monkeyed with.. That reason is the same reason why I prefer the simplicity of SDS coupled to their unparalleled support..

I do like the datalogging feature of the MS system, but then again most people don't even know how to decypher the plots that are logged.. The like it because it looks cool and has nice squiggly lines that look sophisticated..

There are instances where too much information can be just as harmful as no information. If I were to ever outfit a car with MS I'd keep the gadgetry down, keep the system simple and wouldn't use 1/2 the bells and whistles they developed into it... But then I'd be describing SDS and wouldn't need a laptop :-)

Doesn't it use a wideband controller?

Yes, but earlier versions of the SDS (pre V16.6) operating in closed loop would pull the engine to stoich instead of a richer enrichment needed by our engines.

I have two of the prototype chips installed in my 912E and the Pinzgauer, no others are being used in cars, only steady state aircraft engines.. The new set up is driven by an AEM, PLX or similar wide band arrangement and continually will adjust enrichment as much as 25% from any previous value to reach the target AFR that was programmed into the chip by SDS.

In my experience I always make the most power @13:1 and net the best temps, so I had my 16.6 chips burned at that value. With the SDS in closed loop the chip will work to auto correct the AFR to the preset value when the MP and RPM are within the ranges set by the user to actuate closed loop.

I have my 912E set to always run in closed loop from heavy acceleration to just after the decel MP. On the dyno with the Pinz engine we were able to activate the system and get the same AFR and power even when we purposely jumbled up the fuel values as much as 25%.... It does work.

So what this means is the system just got a bit smarter and the chip will accommodate for up to a 25% inaccuracy in fuel mapping for the user.

SDS is always making their system better. When I first started using SDS 5 years ago they were on V12, I just received a V17 system to test on a 914 customers engine and the refinements they make are remarkable.

I think I get it now... The AFR table is burned into the chip, right?

Do you run 13.1 across the board?

Why is it that these engines don't like less than 13.5:1?

Every combo is slightly different and since I don't want to become libel for smoked engines I can't answer that question... There is no "always" in my world.

Rich engines drink fuel and have a stumpy powerband, they don't like to rev or make crisp power. Rich mixtures (12.5 or richer) contaminate oil with fuel that washes past the rings, they hure all around performance and lead to shorter longevity because fuel is a solvent, not a lubricant.

At 13:1 with my combos magical things occur.

When I was tuning recently, I noticed the engine ran like crap between 12. and 13.0( rich).

It didn't like it very much leaner than 13.5.

Why do they NOT like anything leaner than 13.5?


Keith