Question
I'm new to the evo world
I have a evo 9 on speed density

Mods:
Ets upper,lower and fmic
ID 1000
255flp
Fp4r2 cams
APexi exhaust
Speed density

Car made 317 and 300 on a mustang dyno

Now
The guys who tuned it said they hate speed density and it's not necessary
Unless I'm making big power
They said the reason I'm losing my drivability and my idle surge is because it's on speed density
Does this sound right ?

 

from the info i've gathered, that is correct. the MAF isn't very restrictive and works well unless you are pushing enough air out of a turbo that it's in the way.
on the bright side, it's easier to drive the car if you have an intercooler pipe blow off LOL.

i, personally, haven't found a reason to go SD, but i'll never be making more than 400-500whp.

 

I agree with some of that.......

But there are things that SD is good for even with no power

Sd doesn't require you to pull fuel with air like a maf

So you can up mpgs, get overall better driveability and your already half way to most big turbo requirements already if you decide in the future you want more power...

I think your tuner is just unable to calibrate SD and is trying to cover up his weakness by steering you away

Perhaps find a good tuner

 

that's enough motivation for me LOL. if only i could predict the increase. i'd like to go a bit farther between fill ups.
worst MPG on any 4cyl that i've ever seen haha

 

You can do the same thing with a MAF as well, just run it in full time open loop and set your target AFR to whatever...

 

True that Freddie.....
I forgot that

 

i actually thought about that. i've done it before. i just can't remember if i had to do open loop the whole time or if i could just do it for my cruise cells. only one threshold setting can be set, correct?
i also kinda remember that my car didn't like cruising a whole lot more lean than 14.7, though. i think i remember it not liking 15s. it's been a few years.

maybe i'll play with it once BoostedTuning is done with the tune.

 

Still seems slightly easier just to go SD if your not tuning it yourself like the OP

I'm not entirely opposed to running open loop in any fashion, but I maintain a bit of skepticism

 

BoostedTuning tunes my car, i'd just play with the cruise stuff if i decided to. personally, i like sensors doing their job LOL. i'd go SD before trying to run the car in full-time open loop. IF i thought it would be worth the trouble.

 

Ah I see
I've heard nothing but good things about boosted

I'm sure your having a blast!

 

Your tuner can't tune SD. Find a new tuner.

 

 

soon! just rebuilt the engine..then the turbo died LOL.

as for OP: i agree to consult a different tuner. it may not be a bad thing to get a second opinion.

my tuner does great work, i'd suggest hitting him up.

 

I'm in the same boat!....

And I second that recommendation

 

My tuner can tune SD
He tuned the famous jasmine Evo off YouTube
He was just saying I lose drivability and its more difficult to fine tune
I just wanted some pro and cons on SD vs maf
But I'm getting the idea
I believe I'm going to stay SD
Thanks everyone