[pikkashoe]

I noticed something on all the dyno sheets I have seen on here for Procede cars.

Why is there what appears to be oscillation (best way to describe) in torque between 3000 and 4000 rpms. Its not a smooth line like stock (though stock is not completely smooth either). It shows up in about every dyno run.

What exactly am I seeing there?

[pikkashoe]

Anyone?

[Spool]

Who cares, it's fast....


/thread

[Ninjaneer]

I'm not sure. But I did fine one explanation on one case by shiv: Take 7: We finally dyno a Steptronic all proper-like (first post) - he mentions that so much torque was being generated so the dyno was shaking, hence the bumps in that dyno. Not sure if this applies to everything else you've seen though.

[droptop335]

I have a similar but different question:
Seems like all dyno runs I have seen posted start their traces at approx 2000-2500rpm, where the stock and Procede traces are closest to each other. Now, BMW states that max (?) torque is available from something like 1400 rpm to 5800 rpm. But how come the syno sheets don't show that? I'm concerned that the Procede sacrifices low end torque for added HP and TQ higher in the rev ranges. But let's face it, TQ is most important down low, when getting off the line...HP only comes into play at higher revs...

Is this just a function of the way dynos work?

[RiXst3r]

Originally Posted by Spool

Who cares, it's fast....


/thread

its funny how the end result seems to justify EVERYTHING with the PROcede users.

[scalbert]

Originally Posted by droptop335

I have a similar but different question:
Seems like all dyno runs I have seen posted start their traces at approx 2000-2500rpm, where the stock and Procede traces are closest to each other. Now, BMW states that max (?) torque is available from something like 1400 rpm to 5800 rpm. But how come the syno sheets don't show that? I'm concerned that the Procede sacrifices low end torque for added HP and TQ higher in the rev ranges. But let's face it, TQ is most important down low, when getting off the line...HP only comes into play at higher revs...

Is this just a function of the way dynos work?

The factory engine dyno curve will not match a chassis dyno curve. I also beleive that marketing had a part in the 1400 RPM spec...

That being said, most chassis dyno operators will start a pull around 2k revs. Seems to be a fairly standard practice. I am sure you could ask the operator to drop lower but in automatic cars this may not be possible.

[droptop335]

Originally Posted by scalbert

I also beleive that marketing had a part in the 1400 RPM spec...

Meaning that you don't believe it to be true?

[scalbert]

Originally Posted by droptop335

Meaning that you don't believe it to be true?

Meaning that I find it to be a stretch. I would agree that near 90% may be available that low but the true peak torque is not available at 1400 RPM.

According to the specification:

Maximum torque/rpm
300/1400-5000 lb-ft

It may very well have 300 lb/ft at 1400 RPM. But it has more than that at 3000 RPM which is closer to the peak torque seen on many of the chassis dynos posted here.

For any given gear a car will accelerate quickest at its peak torque. Using any performance meter in G-force mode can help identify where the peak torque is by determine at which RPM in a single gear gives the greatest number. The car does not have the same G-force at 1400 RPM as it does at 3500 RPM. This is why I say it is incorrect.

Would I say they are incorrect in saying it makes 300 lb/ft at 1400 RPM; not at all. I would say that they limited the true peak number in the marketing material which is most likely closer to 330 lb/ft in the 3000 - 3500 RPM range.

[cupspeed]

A dyno will reflect the numbers as the vehicle produces. Most late model dyno's will handle up to 2000rwhp. They are very sensitive & will reflect even a very quick hiccup

[pikkashoe]

Yeah I dont buy the dyno shake explanation because I can feel that slight oscillation in the torque curve in my car when pulling in 3rd gear. I thought v 1.45 had cleared it up, but its there just barely noticeable though.

I dont think its boost leak, because it would throw a code.

So what else could cause that oscillation seen in basically every dyno run.

[scalbert]

Originally Posted by pikkashoe

I dont think its boost leak, because it would throw a code.

So what else could cause that oscillation seen in basically every dyno run.

Depends on how large of a leak, a small leak may not throw a code. And depending on where it is could affect the boost control.

The main source for a lower frequency oscillation is typically boost control. Can someone post a dyno with this displayed? If it looks like noise then that is typically iginition related such as getting some minor knock.

[SoCal335i]

Originally Posted by RiXst3r

its funny how the end result seems to justify EVERYTHING with the PROcede users.

Isnt that whats important?

[Dr_Dirt]

Originally Posted by pikkashoe

Yeah I dont buy the dyno shake explanation because I can feel that slight oscillation in the torque curve in my car when pulling in 3rd gear. I thought v 1.45 had cleared it up, but its there just barely noticeable though.

I dont think its boost leak, because it would throw a code.

So what else could cause that oscillation seen in basically every dyno run.

Could be the boost controller adjusting for over/under boost, this could be why Shiv wants people with boost meters to test his new sw.

[derryck]

I don't really buy the whole thing about the car generating 'so much' torque that it rocked a bit to cause the dyno discrepancies. My 03 Cobra has more torque at 2,000 RPM's than the 335i is capable of harnessing without serious mods and it doesn't rock the dyno.

[scalbert]

Originally Posted by derryck

I don't really buy the whole thing about the car generating 'so much' torque that it rocked a bit to cause the dyno discrepancies. My 03 Cobra has more torque at 2,000 RPM's than the 335i is capable of harnessing without serious mods and it doesn't rock the dyno.

While I agree that the torque of the 335i is not going to throw off the numbers if properly strapped down. If loosly strapped discrepancies can occur.

However, I do not think this is the case here.

[droptop335]

Originally Posted by SoCal335i

Isnt that whats important?

Maybe...it depends on what you want out of it. I see 0-60 and 1/4 mile numbers posted constantly as proof that the Procede is faster than some other system, or and so much faster than stock. Yes, using those criteria, that certainly is true. But think about it...90+ % of driving is done between 0 and about 20 or 30 mph. At those speeds, torque is what's primarily moving the car. So I'd be very interested to see a true comparison of stock and Proceded engine torque numbers. I would bet that the difference down low is not nearly as much as it is above 2500rpm...

And I would love to see some 0-20 and 0-30 acceleration numbers...and see how much of a diference there is between stock and Procede. It might influence my "bang for the buck" decision...

[lawdude]

Originally Posted by droptop335

And I would love to see some 0-20 and 0-30 acceleration numbers...and see how much of a diference there is between stock and Procede. It might influence my "bang for the buck" decision...

I'm trying not to laugh.

[droptop335]

Originally Posted by lawdude

I'm trying not to laugh.

Hey, it's your money...

[OpenFlash]

Originally Posted by pikkashoe

I noticed something on all the dyno sheets I have seen on here for Procede cars.

Why is there what appears to be oscillation (best way to describe) in torque between 3000 and 4000 rpms. Its not a smooth line like stock (though stock is not completely smooth either). It shows up in about every dyno run.

What exactly am I seeing there?

Just so that we're on the same page, could you show us the graph(s) you are looking at?

Shiv

[pikkashoe]

Hold on, give me about 10 minutes to pull up the threads. Its just an observation I have noticed.

[lawdude]

Originally Posted by droptop335

Hey, it's your money...

You're trying to figure out whether it's worth spending $1300 bucks to help you with your 0-20 times? Fugitaboutit and keep your money in your pocket.