for what it's worth my daily driver has 700awhp through the stock ecu and stock maf which trapped 139.8 boiling the tires off and bouncing while lifting to shift (D2 coilovers are on the way). This is a full weight car, it even has the stock wing. It's hard for me to get excited about doing a SD conversion for anyone with less power. There's just no need to make it more complicated unless it's absolutely necessary.

I have a new 10:1 motor on the way and if I can't get above 700awhp I'll know I've hit the wall with the stock MAF. At that point I'll convert to SD and find out what it's worth and give people the truth about SD.

I don't sell or steer customers into anything I don't believe in 100% or don't use on our own cars.

 

Some great info in here thanks guys.

 

How many of you guys pushing the MAF are on super lightweight clutches?
Quartermaster, tilton, ect.

How does the car drive? Stalling issues?

 

I have offered this up before, but if anyone wants to send me a MAF I will flowbench test it against a mafless intake. My opinion on this is that swapping to SD to lose a restriction in the intake will yield negligable gains up to an airflow that most people are not hitting. I can test up to 3000CFM, mabye find the airflow rate that may make it worthwile to pick up hp from a restriction, if the honeycomb can handle it..

Also, the other thing the MAF has going for it is the honeycomb. This is a double edged sword but the honeycomb helps provide laminar flow to the compressor wheel which makes a bigger difference then what most people think, even if it hits a bend or two on the way.

 

tilton twin carbon and BF 272 cams, pretty much the worst combination imaginable for inducing a stall. Light weigh clutch and very little vacuum. The idle has to be ~ 1200 to reduce stalling and will still do it on rare occasions.

 

my race car has quartermaster twin, knife edged crank, and underdrive pulleys. my car has essentially no rotating mass its a 2.3L too. the MAF works... we had a hard time getting the injectors scaled for a while (fuel supply issues), but after putting in the cell with a more consistant pump it idled fine.

 

I'm probably the guy the OP spoke with, sounds like something I'd tell someone about SD. I've had multiple tuners here at the shop to tune SD cars, all guys from these forums who were known for how great SD is. Personally, I would not run SD on the stock ECU. Will my opinion change in the future, it most certainly could as I use to HATE the stock ECU. Project White opened my eyes to the stock ECU. That car was full weight minus the front and rear bumper beams. 2.3 engine, ported head, STOCK MAF with honeycomb in it, 3" double bend intake pipe, BF272 cams, 1200 cc injectors, pump gas and E85 with map switching. The car runs AWESOME. On E85 at 30 psi of boost it made 520 whp and 500 ft lbs of torque and ran 10.3 at 138 mph in the 1/4, on an FP Red. Mileage is great, idle is great. I had a LOT of time in getting it to run well. I have put time in on the SD's and have only had a few that ran acceptable. One of which was mostly done and tuned when it got here and the owner has posted in this thread already, he self tuned most of it.

The car that was mentioned at the shootout, there were wiring issues with that car that took 6 hours, just for reference. Also the guy who ended up tuning that car also tuned the fastest stock ECU EVO ever too.

The power is there for sure with SD. I've told this story 10 times in the past but will tell it again. Had a customer here a few years ago. Running an AEM EMS on speed density. Had the car finished and noticed he still had his MAF in place with the big open filter we sold on the end of it. The car if I remember right was only making about 325 whp. I told him having the MAF in place was dumb and he said he'd let me take it off and put a filter in it's place as long as I'd put it back if it didn't make a power difference. So I pulled the MAF out, put a K&N filter on the end of his MAF pipe and re-dyno'd. 15 whp was the gain, nothing else done to the car.

There should be some pumping losses with the MAF in place, even though it is quite large and does work very well.

I am in the frame of mind now that most EVO's can run the stock ECU, make great power and run great and most of all stay in one piece. If someone is going for setting some type of track record my suggestion is then to go to a stand alone and of course speed density. Short of that, stock ECU, stock MAF is what I recommend now.

 

i would say that theres no way the flow through the intake is laminar once the turbo is spinning (idle, and possibly cruising it might be). the reynolds number is reduced by adding the honeycomb and seperating the air through "tubes" with smaller diameter/cross sections before the MAF, but once its through the MAF, you have a large diameter, and extremely high speeds, thus a rather large reynolds number.

 

We have multiple cars running SD with customers that are VERY VERY happy with it.. I dont tune so i cant get into the tuning aspect of things however ill ask that some of our customers post up on what they LIKED about the change to SD and any dislikes.. I know 2 cars that i have personally driven that drive like a JEWEL on SD..

Mike

 

30 minute tune is pretty fast.. Doing driveability, and WOT, changing boost levels, boost controllers, wastegate preload and all I have yet to see done on a fully built car with 35 aftermarket parts even on MAF..

Ecu controlled boost worked well on the Bastard.. And was tuned by that same guy that BROKE EVERY stock ecu record there was at the track.. Everyone has a different approach and we are happy with Diiirks approach to tuning SD as it has filled my signature..

Mike

 

I have personally tuned my own car on stock ECU SD and it honestly ran perfectly. If you were to drive it, you would have absolutely no way of telling whether it was on MAF or SD. I've been tuning my own 4G63 cars for many years and my maf and SD tunes run very well.

As I mentioned previously, the only issue that I had that should be fixable with a little coding change is the heatsoaked IAT sensor at startup, causing a lean start.

Idling, cruising, WOT are all absolutely smooth and perfect, even on this iteration of stock ECU SD code. It all comes down to the person doing the tuning and whether or not they really understand what's going on and how to tune the present patch and various tables.

Future iterations, if and when done, should make things a bit easier with 3D VE tables and the such, but stock ECU SD can and does run very well in it's present iteration.

But, I do tend to agree with some others that SD is not really necessary at this point for a lot of people. The stock MAF works very well and for a car running well, there aren't too many reasons to switch, especially with the couple minor issues with SD at this time. But, also as others have mentioned, SD does eliminate all MAF based issues for highly modified cars that have them.

So, to each his own. But, SD on the stock ECU is doable and can run very well and should get better in the future.

 

After reading this thread, it has become more clear that it is pointless on running SD with the stock ECU. Factory ECU's for the Lancer Evolution have come along way. Luckily with the good tuning programs, we are able to make extremely powerful cars on stock ECU. I for one wanted to convert to SD for the simple fact of squeezing out some better numbers, and not having to worry about issues running VTA. It's just like Mellon said, there is no point on converting until you hit that brick wall with the MAF being at its limit. Def not needed on stock ECU. AEM is a different story IMHO.
Overall alot of great knowledge in this thread, and this should clear up alot of questions that others may have about converting to SD.

 

Sure, but I would be willing to be there is still a difference.. As far as laminar flow not having an effect on turbocharged engines, I can only say it has a very good and profound effect and we have hundreds of hours of data to back it up. I will see if I can dig something up to share

 

Interesting discussion on the value of SD. I have yet to tune a stock ECU SD setup, but I have been considering running it on my own Evo for quite a while. The two advantages I see are the potential for more power through less restriction in the intake (I don't think SD itself allows for more power), and possibly to reduce liftoff stutter from the DV.

One distinct disadvantage I see in SD (and this applies to any SD setup including AEM) is that SD does not extrapolate well when installing new parts that add power, or when turning up the boost to levels that had not been previously tuned, or when trying to tune well outside the optimum VE range of the motor. I was doing an E85 tune on a friend's (MAF equipped) Evo a few weeks ago, and the first step for E85 was dialing in timing and AFR on the pump gas boost curve. After that, I started turning up the boost. Boost went up no problem, but load changed very little, if at all. Without someone of accurately measuring the VE out in this range of boost, MAF and SD would give very different results for the load calc. I think MAF was more accurate because the car would not make any additional power. Without having a way to accruately generate a VE curve, the SD load calc is very much of a guess. For AFR, an inaccurate load calc isn't that big of a deal because most of the time, we aim for a constant AFR across the rpm range. However, timing is highly dependent on load. Seems like this could make it very difficult to accurately tune an SD setup.

A month ago, I was sure that I would eventually start running SD, but after realizing this limitation in SD, I'm having second thoughts. If I can find a way to deal with the honeycomb in the MAF, I might stay with MAF even if it does cost me some HP due to the restriction.

 

You also won't see boost leaks in the tune as easily.

Hell I had a IC pipe pop off on the dyno and didn't figure it out until a couple pulls later... lol

It's also the nice thing about SD, you can have a pipe pop off and it will still drive and idle smooth as glass.

- Bryan