Dyno Day

[JSRS6]

the curves start too late, as in too high up in the rpm's

[V8weight]

the curves start too late, as in too high up in the rpm's

Extra crispy or original recipe?

[DHall1]

Again, warm.

So do you think this graph is real or a hack job?

Why would the curves start later? Did someone just draw lines on the chart? Which curve is worse and why?

What would explain the reason why the curve starts later? If you believe the chart is real.

the curves start too late, as in too high up in the rpm's

[JSRS6]

The fact that BOTH the stock and tuned curves start at the same time, says that it isnt kosher. The stock graph should start in the low 2000's, while the giac tune should start a little later, but build up higher. at least thats my understanding from owning a b5 s4...

[DHall1]

Its right in front of you. Read my questions again. Look at the graphs and ask can this really happen?

Peak torque. When does it occur? What the mechanical theory behind peak torque and why is that important? When does peak torque happen in the giac graph? Is that a problem to anyone? why? tell me.

[JSRS6]

torque early, horsepower late. it takes too long to build up.

[DHall1]

Nope, you are missing it. What makes torque? What is the single largest factor in making peak torque in this turbo platform?

Go look at Pat's graphs. Compare the two.

torque early, horsepower late. it takes too long to build up.

[JSRS6]

the actual boost produced. time it takes the turbos to spool up.

[DHall1]

Ding ding

Now what does it take to spool up the turbos? This is key

the actual boost produced. time it takes the turbos to spool up.

[JSRS6]

hot MAGMA...j/k
exhaust gases, and enough of it from the engine running at least at a certain speed.

[DHall1]

Ok,

So you have a closed wastegate in the turbo and exhaust gasses.

What makes the turbo spool faster? Say at 2200rpm. How can we get the turbo to spool faster?

hot MAGMA...j/k
exhaust gases, and enough of it from the engine running at least at a certain speed.

[JSRS6]

more a/f in, more exhaust out for a given rpm...

[JSRS6]

so timing and fueling

[DHall1]

Not really.

We want more exhaust flow. How are we going to get it? Increase in rpm yes....but how do we speed up this entire process to create a vicious cycle that starts to feed upon itself.

more a/f in, more exhaust out for a given rpm...

[JSRS6]

accelerate?

[DHall1]

Ding, ding

At the point of positive boost pressure you start to add fueling. This creates the vicious cycle and it starts to feed upon itself. Exhaust gets hotter and flows faster....turbine spins faster gets hotter....need more fuel at a faster rate to feed the monster....monster gets fuel and gets hotter......Bingo the turbo is lit and we are set for takeoff.

Now, look at that GIAC graph and tell me whats happening. Better yet, here is a GIAC tune and dyno run. What do you see

so timing and fueling

[ttboost]

Epic fail

Try again. All the information you need to solve the problem is visible in the chart.

Why do the TQ curves seem to start at exactly 225or so ft/lbs...TQ ramp looks wrong...

[DHall1]

Where the curve starts or ends has nothing to do with the problem. The information you need to solve the problem is in the graphs. The body of the curves tell the story. Compare and contrast to Pats chart. Something sticks out like a purple horse.

Why do the TQ curves seem to start at exactly 225or so ft/lbs...TQ ramp looks wrong...