Pro's and Con's to Speed Density Tuning on FI..
 

Just like the topic says.. In the future I might consider going 3 bar SD.

I am in SD 2 bar. Going to 3 bar with my new setup. I really dont have any complaints at all. It takes time to set it all up and build the proper tables but once its done it drives great and smooth. My idle locks in place with no surging or bucking. I will say that I have had to make changes in cold weather and hot weather. But other than that the OS's work very well for our cars. Its all in the amount of time and experience you have with tuning. That will be the key in order to a SD 2 or 3 bar car running correctly. We currently have my partners 2003 Z06 in 2 bar with 900 + to the wheels running very well. We have gone 500 mile road trips and it just drives so well and tame. Untill you smash the gas. It amazing how much power you can have and just get in the car and go. Hope that helps.

JMG

What you just said is what I have heard as well. I have no intentions of pushing past 900rwhp. My clutch wont hold it and I dont think the rest of the drivetrain would last very long..

The major disadvantage for me is that I don't do my own tuning. It takes many many hours/ days even to get the tune dialed in. If you are not doing your own tuning, you will be hard pressed to find a tuner who will do it for you, and then if you do, it will cost a LOT of coin.

Are you doing your tuning?

I got a newbie question on this, speed density versus what? By speed density I assume you are talking about using, the maf setup as opposed to map/tps.

harris speedworks jus did a 2 bar on my setup. thing has great manners and lots of power when ya mash on it. much more reliable than the MAF.

I have heard of MAF-T and some other things too... how do they compare to SD?

Maf-t extends the tables. So its like running SD but still using the maf.

You are removing the MAF completely. Building the maps off of Map,IAT's and spark tables etc. Of course on my partners Z06 we left the maf on due to the fact the IAT is with the maf. Then we had to send off the 0S to have the reduced engine power taken out.

Any drawbacks or benifits to that vs: SD?

Your still using the Maf to compensate in whatever atomsphere you are in. I am no pro with the Maf-T. SD works well. Its all in what your Tuning/Tuner can and cant do. Im sure Slowhawk,Harlan or Kyle can fill you in some more.

For small setups like 8lbs of boost you really don't need SD. We ussually switch to SD on 10+lbs with Cams or Turbo cars. SD is also better with low vacuum motor's from big Cams. Setting it up is not hard but tuning it in takes time.We ussually take 2-3 days of driving,Tried a load dyno but the tune was too far off on the road after. I do suggest you run a permanent wideband if in SD though.

ok well I am rather new to FI and SD tuning, but I am building a turbo set up and was considering going with a SD tune. What kind of up keep on the tune is there? (do you have to adjust things according to temp, etc) What is a estimate on price for this kind of tune as I would not be doing it myself? What is 2 bar and 3 bar SD and the difference? Any other input that would help me out I would appreciate. Thanks.

i'm assuming by maf-t you mean maf translator...which ones are you guys using?? are there any really good ones out there??

I have tuned many cars using HP tuners 2/3 bar OS. As far as tuning is concerned it is my favorite thing to work with and IMHO the only proper way to accurately tune a forced induction car capable of maxing out the MAF sensor.

Driveability is exceptional, much better than the MAF. Change your boost level on the fly and fueling is perfect at any setting. Just make sure you have the proper octane fuel in the tank for a given power level.

Once tuning is completed no further changes or adjustments are necessary. Their are millions of cars on the road built and tuned speed density from the factory. They (like the LS1) do not need to be re-flashed when the weather changes.

I am SD w/ BS3 and it works great

The changes I make are minor. But it got so cold here this year I had to make a different tune for startups. BTW thanks for the cam info. Looks like Ill be giving you a call. :judge:

I'm sure SD is great when done right - but FWIW I haven't had any issues with my MAF setup at 13-15 psi boost. My car runs mid 10's @ 138 MPH without meth in the summer heat on pump fuel so I can't complain.

Your car is just flat out fast Mark. You are 1 bar right?