**CHALLENGE** - TURBO LAG TEST using a log

[jkholder09]

Very good response Chris. The truck really performs well, you have done a great job on it.
I would bet with a downshift that charger would light about 1 second faster, or .25436 seconds FASTER than stock.
:thumb:

 

[coker6303]

Got time to post the log. Next time I have time to drive my truck I'll try and get a stock one.
1467-2334 RPMs 51-58 MPH 5th gear T/H ran it up to 20PSI = 1.88 Sec.




Try and remember to do this one too. From a dead stop to how fast did you go?

Maybe I'm seeing it wrong, but your map is only showing a 10psi gain, you cut the run short. :thumb:

 

[coker6303]

Very good response Chris. The truck really performs well, you have done a great job on it.
I would bet with a downshift that charger would light about 1 second faster, or .25436 seconds FASTER than stock.
:thumb:

I'm not seeing where you are getting this?

 

[coker6303]

Damn, 3.4 seconds.. a 75 that spools almost as fast as a stock turbo...

It took almost 50% more time to spool than my stock turbo with the same converter.

To be exact, it was 41.66666666... percent more time.

It is quick for a big single, I'm impressed!! Really shows the value in converter choice. But you see the turbo characteristics in the long spool time when locked from 1500rpm.

But look at it like josh is saying, that's a big percentage gap from a standstill. And you know that little but of time is huge when you figure the roll out rate from a stand still. The stocker is getting a nice head start! Lol

 

[jkholder09]

I'm not seeing where you are getting this?[/QU

Basically I looked at the turbine map with a .90 a/r housing and then solved back for the air volume/temp/density and velocity through turbine wheel. Then I added the additional rpm that would be spinning in 4th gear. That additional rpm adds significant air density and drive. So I correlated that to the acceleration rate of the turbine and compressor wheel assy and it accelerates almost exactly 1 second faster.
I will say that the additional engine rpm will require more air mass which in turn will lower inlet pressure(boost) by a small amount, but the overall rate of acceleration in the turbine is increased so drastically it really becomes a minimally significant variable.

 

[coker6303]

I'm not seeing where you are getting this?[/QU

Basically I looked at the turbine map with a .90 a/r housing and then solved back for the air volume/temp/density and velocity through turbine wheel. Then I added the additional rpm that would be spinning in 4th gear. That additional rpm adds significant air density and drive. So I correlated that to the acceleration rate of the turbine and compressor wheel assy and it accelerates almost exactly 1 second faster.
I will say that the additional engine rpm will require more air mass which in turn will lower inlet pressure(boost) by a small amount, but the overall rate of acceleration in the turbine is increased so drastically it really becomes a minimally significant variable.

You just completely missed the comparison at hand. Thanks for trying to sound more intelligent than you are. please do not derail this thread like you have other topics in the past. :thumb:

 

[JoshH]

I did another 5th gear run from cruising throttle. It's so damn hard to accomplish without a kickdown to 4th. You have to peddle it just right.

Could you load a different TCM tune that wouldn't downshift as quickly? I'd like to see how fast it spools if you're able to give it more fuel.

Out of curiosity, how smokey is it when you were doing these tests?

 

[Dirtymaxx03]

Could you load a different TCM tune that wouldn't downshift as quickly? I'd like to see how fast it spools if you're able to give it more fuel.

Out of curiosity, how smokey is it when you were doing these tests?

im gonna go out on a limb and say he is blacking out the road hardcore lol

 

[JoshH]

I would bet with a downshift that charger would light about 1 second faster, or .25436 seconds FASTER than stock.
:thumb:

You're an idiot if you actually believe that turbo could ever spool faster than a stock turbo.

 

[jkholder09]

You're an idiot if you actually believe that turbo could ever spool faster than a stock turbo.

And what would that make you if I could prove otherwise?

 

[JoshH]

And what would that make you if I could prove otherwise?

Prove it, and we'll go from there. Under the same circumstances, there is no way that turbo will spool faster than a stock turbo. You still haven't even contributed anything at all to this thread. Lets see what your turbo will do.

 

[Dozerboy]

Maybe I'm seeing it wrong, but your map is only showing a 10psi gain, you cut the run short. :thumb:

Ya not sure what the deal is I was going off my boost gauge. Its tapped in just before the grid heater. I wonder if my MAP is wrong. Look at my RPMs I have a bigger swing and my speed swing is similar to Joshs. I'm a full second faster then his at 1500RPMs though.

Might have something to do with my converter too. I logged converter clutch duty cycle and it was a constant 65% no matter what I did.

I don't know...

 

[DMAXchris]

Could you load a different TCM tune that wouldn't downshift as quickly? I'd like to see how fast it spools if you're able to give it more fuel.

Out of curiosity, how smokey is it when you were doing these tests?

Yeah. I could mess around with it and see if I can go WOT without a kickdown.

It's not that smokey in 5th. I would say a steady stream but not thick. 6th gear would be a whole different story though. That will black out the highway!

 

[PureHybrid]

Can you use the DVT controls for the trans while logging? Excuse my ignorance I've just never tried it, and it might be quicker than writing a TCM tune???

 

[Chevy1925]

You can not log then.

 

[JoshH]

Ya not sure what the deal is I was going off my boost gauge. Its tapped in just before the grid heater. I wonder if my MAP is wrong. Look at my RPMs I have a bigger swing and my speed swing is similar to Joshs. I'm a full second faster then his at 1500RPMs though.

Might have something to do with my converter too. I logged converter clutch duty cycle and it was a constant 65% no matter what I did.

I don't know...

You had a downshift to 4th. That's why it's so much faster than mine. RPM would not get over 2300 at 58 MPH in 5th gear.

 

[jkholder09]

Josh H

http://youtu.be/OERkCCmiPLg

I work on trucks I do not produce action movies, sorry for the poor quality movie.
The truck is just an old shop that sits around. It is filthy dirty and has 250k miles on it.
Its hard to see the tech 2 screen but you can see 20 psi of boost instantly, and if you watch the maf it just jumps from 200 to pegged at 499 instantly.
EGT's do get a bit high and you can see by the pipe there is a bit of fuel as it lights.

The top pids on the tech 2 were rpm, maf, boost, and app%.

Its a little easier to see on the edge monitor, boost is in the lower right corner at the end of the video.
On the last run Josh I put in the lock in 5th trans tune, the only rpm change you hear is the tc lock.
But if you look the truck started at about 45 mph and carried 3-5 psi, then within 2 seconds of video time the boost was at 22 psi, and never goes higher.
I am pretty sure this truck lights faster than stock.

 

[Dozerboy]

You had a downshift to 4th. That's why it's so much faster than mine. RPM would not get over 2300 at 58 MPH in 5th gear.

Nope I log gear and can sure feel a gear change. I can feel the converter unlocking before it shifts easily enough to peddle the throttle keeping it from down shifting. Their isn't anything in the ECM tuning that affects the converter locking is there?

I took more logs today and will post them. The stock one might tell the story since it felt way different. More so then just a lack of power I think.

 

[coker6303]

Josh H

http://youtu.be/OERkCCmiPLg

I work on trucks I do not produce action movies, sorry for the poor quality movie.
The truck is just an old shop that sits around. It is filthy dirty and has 250k miles on it.
Its hard to see the tech 2 screen but you can see 20 psi of boost instantly, and if you watch the maf it just jumps from 200 to pegged at 499 instantly.
EGT's do get a bit high and you can see by the pipe there is a bit of fuel as it lights.

The top pids on the tech 2 were rpm, maf, boost, and app%.

Its a little easier to see on the edge monitor, boost is in the lower right corner at the end of the video.
On the last run Josh I put in the lock in 5th trans tune, the only rpm change you hear is the tc lock.
But if you look the truck started at about 45 mph and carried 3-5 psi, then within 2 seconds of video time the boost was at 22 psi, and never goes higher.
I am pretty sure this truck lights faster than stock.

Please tell me you know this was downshifting where you are referring to spoolup?? We are not looking for downshifted spool up time... truck runs good though!

tune the TCM to hold 5th and do a roll from 1500rpm using EFILive and post your results with the section highlighted so we can compare equally.

 

[JoshH]

Nope I log gear and can sure feel a gear change. I can feel the converter unlocking before it shifts easily enough to peddle the throttle keeping it from down shifting. Their isn't anything in the ECM tuning that affects the converter locking is there?

I took more logs today and will post them. The stock one might tell the story since it felt way different. More so then just a lack of power I think.

The gear PID has a delay in it. You can see the RPM jump with no change in converter slip speed (stays at or very near zero), but the gear PID shows a downshift to 4th right before you let off. If you log the boxratio PID, it will instantly show a gear change because it calculates the ratio by looking at turbine and output speeds. Nothing in the ECM for TCC.