I dont understand...why do they have to ?

 

its a mathematical formula of the relationship between trq and hp. That's all I know...but I know that they must cross just after 5200.

 

this is an excert from...

http://auto.howstuffworks.com/question622.htm

on the 5250 calculation.

"Have you ever looked at the specs of an engine in a magazine and seen something like "this engine makes 300 pound-feet of torque at 4,000 RPM," and wondered how much power that was? How much horsepower are we talking about here? You can calculate how many foot-pounds of horsepower this engine produces using a common equation:

(Torque x Engine speed) / 5,252 = Horsepower

The engine that makes 300 pound-feet of torque at 4,000 RPM produces [(300 x 4,000) / 5,252] 228 horsepower at 4,000 RPM. But where does the number 5,252 come from?

To get from pound-feet of torque to horsepower, you need to go through a few conversions. The number 5,252 is the result of lumping several different conversion factors together into one number.

First, 1 horsepower is defined as 550 foot-pounds per second (read How Horsepower Works to find out how they got that number). The units of torque are pound-feet. So to get from torque to horsepower, you need the "per second" term. You get that by multiplying the torque by the engine speed.

But engine speed is normally referred to in revolutions per minute (RPM). Since we want a "per second," we need to convert RPMs to "something per second." The seconds are easy -- we just divide by 60 to get from minutes to seconds. Now what we need is a dimensionless unit for revolutions: a radian. A radian is actually a ratio of the length of an arc divided by the length of a radius, so the units of length cancel out and you're left with a dimensionless measure.

You can think of a revolution as a measurement of an angle. One revolution is 360 degrees of a circle. Since the circumference of a circle is (2 x pi x radius), there are 2-pi radians in a revolution. To convert revolutions per minute to radians per second, you multiply RPM by (2-pi/60), which equals 0.10472 radians per second. This gives us the "per second" we need to calculate horsepower.

Let's put this all together. We need to get to horsepower, which is 550 foot-pounds per second, using torque (pound-feet) and engine speed (RPM). If we divide the 550 foot-pounds by the 0.10472 radians per second (engine speed), we get 550/0.10472, which equals 5,252.

So if you multiply torque (in pound-feet) by engine speed (in RPM) and divide the product by 5,252, RPM is converted to "radians per second" and you can get from torque to horsepower -- from "pound-feet" to "foot-pounds per second."

hope that clears it up, yeah right.

 

Thanks Tigg488.....you didnt have to go through all that typing for me . But now I know . Dont know how long it will stay in my head...lol....

 

Look at the graph again and you may note the HP scale is not the same as the TQ scale.

That is why they don't cross at 5252.

Michael.

 

yeah thats what i said in a previous post , that must be the reason. and BTW i copied it, theres no way i would type all that.

 

^^^ROFL^^^^

 

...I think you may still be missing the potential problem, which is that depending on your location (altitude, temp range,etc), even if you are staying at the base boost level, the base TS flash may not translate properly, so that in order to keep the car properly tuned (not necessarily performancewise but safetywise) you will still need to tweak the tuning on your car. If you are not close to an authorized TS reflasher with access to a dyno, this can become a huge hassle if you have to keep mailing off your ecu back and forth until they get it right. This is why some form of user adjustable fuel management solution becomes much more practical, even for those who want to keep the base boost levels at safe tuning.

Turbonetics,
...again, I truly hope you will consider the impracticalities of a TS flash options and opt against this for the sake of your customers (I plan to be one of them very soon). This looks like a great product, and I know that customers will appreciate it if you go the extra step so that they don't have to go through potential hassles such as this.
I also wanted to say thanks for keeping us up to date with all of this information. I am sure you already have more than a handful of people waiting eagerly for the release of this kit.

 

the engine managment is still the largest hurdle in our design freeze and out of all the components within the system it's also the only things we are not manufacturing ourselves therefore have the least amount of control over...ughh.
there appears to be few options that will satisfy everybody or at least most everybody. one of thing we wanted to stay away from was cutting and splicing the stock ECU harness, obviously plug and play would be most ideal but very little seems to be available. We are from from stopping the search but if anybody has suggestions we are all ears.
So...if you had the options:
1) Flash ECU
2) Cut and splice stock harness for a piggyback style managment
3) Handle the engine managment on your own

how well does the Greddy system really work? and is it plug and play?

 

The GReddy eManage works like a champ. It is IMHO the BEST piggyback ECU available due to it's options and functionality. It is definitely plug and play.

 

I second Chris's comments. In my opinion, the eMange is the next best thing to a stand-alone computer. The eManage, unlike many other piggyback units, has actual drivers for the injectors and ignition coils, so it actually adds IPW or delays timing without tricking the ECU...it actually takes the stock signal, and then adds to it. It also allows you to instantly scale larger injectors via MAF signal adjustment. It's cheap, highly programmable, and very functional.

The only draw back is that you need to cut/splice the harness...but who cares...it hasnt stopped about 100 people or more from installing the greddy kit.

I also understand that there is a company that has created a plug in harness, so you dont have to heck the stock ECU wiring. I'm sure someone can dig up the post for several weeks ago.

 

Not to be too critical ,at this point but....

Even after you fiinsh "tuning" this setup , there is littel probability that your TQ curve is going to "magically" change into anything close to the that of the TT setups already available. To each his own, I understand Turbonetics is seeking a low entry cost. Frum members should not hold out fo a pipe dream "no pun intended".

The significant technical shortcoming of this type of approach is that much of the Exhaust manifold heat energy is dissipated in the "long-long-long" plumbing up to the head unit. Note on a TT setup the head units are very tightly coupled to the exhuast manifiods which improves spool-up "dramaticaly". You might gain a little by ceramic coating your manifold inlet plumbing, but tit wont turn and apple into an orange.

 

What!?! Ok, I have to find this now!

 

Standalone...hks f-con, thats what I'm gonna use once I get my hands on this kit. So yeah I'll buy the kit now....sponsorship I need more power and I want this kit So send me what you got now and I'll make it work

 

Hmmmmm... I have been searching and can't seem to find any info on this. I did a search for the word "emanage" going back as far as July and I can't seem to find any mention of this harness. Do you remember who made it, Sharif?

-Chris

 

There was a post by "Skidazzle" on how to make your own PnP adapter I believe for the stock harness.

Look through his posts for something a long the lines of "For those of you who are tired of splicing into your ECU Harness"

I think it was something like that...... I hope this helps.

 

Woo Hoo!! I found it! Thanks for the info, ColecatZ

Here's the link to the thread for those who are interested

-Chris

 

I understand what you're saying and I agree that with the compressor setup they used in the dyno its not going to be a completely different car no matter what "tuning" is done. However as Turbonetics said they have not settled on that exact compressor set up. Unless I am mistaken wouldn't altering these things change the properties you were referring too (ie: sppol time, power levels at given engine speeds, etc)

 

WRT
"Unless I am mistaken wouldn't altering these things change the properties you were referring too "

Sure a bit, but let me rephrase , your not going to turn and apple in to "two" oranges. The apple will still appear more like an centrifigal SC than a a TT.

 

Oh,,,,right of course. I dont doubt you one bit on that. But then again I dont think this kit was meant to do that either. I have always been biased to the Centrifig. SC kits due to the nature of their design. Morderate power, ease of installation, power when i went it but not always there (boost building higher up). I think what I like the most about the Turbonetics kit is its similar power band to a centrifig SC yet I prefer the efficiency of a turbo to a parasitic system with further complications such as belts, pulleys etc. After looking at the numerous posts about torn belts, wrong pullies, pullies falling off, guesstimating pulley size, I feel like this is the "A Beautiful Mind" forum. (its a joke of course) What I guess I am trying to say is that I would like a Cent SC type power band and numbers but without the headaches of pulleys.