Is Speed Density tuning required for under 400HP street driven cars
 

I would like to bring back a lot of useful information that has been removed from one the threads.

Some tuners are saying that Speed Density tuning is required for high HP cars. Some others say MAF based tuning on modern cars is sufficient for most people goals.

So let's say for an average Joe with HP goals for under 400HP with no plans on building engine and street driven car, would Speed Density tuning be needed or provide any benefits?

Here's some info:
http://www.pcmforless.com/index.php?...ning&Itemid=56
http://support.moates.net/theory-speed-density/

no. i can tell you unequivocally that you do not need an sd tune to make 400whp in an FI 86. i watched it happen this afternoon.

i'm running ~10psi on a gtx2867r and am nowhere near maxing my (blow through) maf. only needed to increase the limit in the rom from 200g/s to 300g/s.

speed density will be necessary at some point, but it's not 400whp.

Its not but it does come into play eventually. I dont think anyone ever said it was mandatory. Issue is most tuners arent going to sit on the forum and give you a blueprint for how to replicate their results. I personally would like to see more individuals push the barrier. At the same time smack talking an option over another doesnt make sense. i say make a educated choice. I have OFT ECUFLASH RomRaider ECUTEK & BRZEDIT. I looked them all over and made my decision based on my personal opinion. But there is a major difference between a commercial product and non. As a business owner my major concern is support if its not backed up it goes to the bottom of my list. Same reason buy products from manufactures based on brand. You can easily purchase something on eBay that looks them same but when it falls apart where is that contact number to the factory in China. 90% of our tunes which eclipse the 400 mark are still MAF based. Above that mark you run into more important issues than the limit of your MAF though.

Why does speed density have to come into play only at higher HP levels? I ran it on my last STI that was about 340whp. I switched to SD to allow more freedom in the design of the V-Mount intercooler and rotated turbo. I have considered switching my BRZ to SD again for the same reason. I'm currently trying to find a local tuner who can do a SD tune with EcuTek.

what do you consider higher HP levels because to be honest at this point on the FA20 motors I have personally moved that bar well above the 400whp mark. Simply because the knowledge is evolving for all those involved. What we consider a platform not ideal for FI little over a year ago has not become common place with multiple options on the market.

to me +400 is high when starting from 200, I don't plan to get anywhere near that but would still like to run SD. On my STI switching to a SD tune with Cobb software only meant a little more tuning time.

Honest Question: Shouldn't a tuner know that it's the experience that makes all the difference in the quality of the tune, and therefore enlightening the public as to the basics of tuning would encourage a customer to choose that tuner over the next? This seems to be more true with our engines as there is alot more going on with 4 cams to control and 2 complete injection systems to manage, showing the community that you have a firm grasp on all that needs to be accounted for would go a long way as far as consumer confidence goes. (You in this sense is not aimed at you but at each tuner individually)

It seems however that any tuner opening his book of knowledge and encouraging understanding puts alot of the resident tuners on edge, it isn't as if reading a tuning guide is going to make you an expert tuner. Well established tuners do know this. That's why alot of the great tuners hold clinics and produce videos to showcase their knowledge, many a want to be tuner has looked down that dark alley and said..."glad you understand...because I don't...take my money and do your magic keyboard dance"

IJS wouldn't it be better if all this discussion wasn't looked at as bashing (unless it actually is) and it was looked upon as information being shared, (which it can genuinely be).

Mike

The basis for tuning this motor is out there and asking that question isnt uncommon I have customers that ask well detailed questions through out the tuning process. Someone will come along and write some sort of documentation or you can read many of the ones out there for Subaru ECU strategy thats nothing new. How do you think people are learning to use the options that are available. So its not like we are concealing information that you cant google from open source forums or read in a AP tuning guide.

there's very little new to learn in terms of the technical aspect of subaru ecu tuning. we have one of the most well-documented, reverse-engineered ecus ever made. they've been cracked and well understood for years. we're not really breaking (much) new ground here.

Exactly

Well, unless my memory fails me, you have posted before that the MAF tuned car wasn't able to do much to hit the 500HP goal?

now that is a good question.
There was a lot of talk but as far as I remember no one actually said at which HP level the stock MAF will be (if so) a limiting factor. Which is why in this thread I picked 400HP as I suppose (i might be wrong though) most folks will be happy with 2700lb rwd car having 250-400HP.

I would be happy with a 2700lb car :)

You could with a larger 3.5" tube but thats not why goal. Te cars run into a number of other issues above the 400 mark besides MAF. that seems to be more of a concern for a basis on software vs software argument. Ive moved past the MAF issue long time back. Ive been working on making the power reliably with some new changes we have been testing. these are software related so dont bother trying to drag out another discussion. these are physical issues on individual components in the vehicle.

Well FI is a drug and knowing you can get more and seeing your friends gets more usually changes you individual goals in a short time frame. Its one thing when youre stuck with something that has no aftermarket support, but once you have backing you tend to grow a little each day as what your new expectations will be out a of a vehicle. I remember when 300hp was great in this little car, then i felt 400hp and the car still was well mannered....hmmm then came 450hp ok this is feeling nice.....how about 500hp....Now thats a car..... every new goal raises the bar and honestly until you experience it you cant say it isnt pleasant and worth the effort. Your always happy with your car till you drive something better thats within your budget. Same thing with everything else in life.

We're missing a whole other component to this conversation...;)