[jpsimon]

Originally Posted by G37KILR

I wonder is this is really safe on the turbos maybe Shiv can respond now about an installation error or something once again that leads back to the OP doing sumthing wrong and not the V3.

there is nothing wrong, read the whole thread.

[Tuned335i]

Originally Posted by E92Pilot

Seems like the spike gremlins found their way into the V3...

Originally Posted by G37KILR

I wonder is this is really safe on the turbos maybe Shiv can respond now about an installation error or something once again that leads back to the OP doing sumthing wrong and not the V3.

I realize it's an open forum, but I don't understand why people who have a history of trashing Shitv/Vishnu (E92Pilot) and who don't own the tune (G37KILR) insist on trolling and commenting in threads that they know nothing about, and no legitimate interest in, other than to start an argument.

I would think there are enough BMS or other tuning threads to hiijack and these types of people wouldn't show up in every thread where a PROcede user is having an issue.

[stressdoc]

Let's keep to the facts and avoid irrelevant digs.
Thanks to Scalbert and others for their technical advice.

[scottp999]

Originally Posted by Panoz

I'm happy to hear that...please define "perfectly"

Without Flaws

Enjoy your car and tune. There is nothing wrong. Really.

[scalbert]

Originally Posted by E92Pilot

Seems like the spike gremlins found their way into the V3...

Originally Posted by G37KILR

I wonder is this is really safe on the turbos maybe Shiv can respond now about an installation error or something once again that leads back to the OP doing sumthing wrong and not the V3.

If you are to post, please identify the issue being referred to.

As shown, the spikes are to be expected and occurred in every tune including stock. The only reason others do not see this is that there is no data logging is available with the other products.

But to clarify further for those who obviously cannot consider the specifics involved or may be lacking the thought processing capability:

The TMAP sensor, which is where the pressure readings come from, is located a couple of inches before the throttle body. When the throttle pedal is lifted the throttle closes (I suppose I need to be very specific for this crowd). Even though the throttle closed, the air is still moving inside the intake pipes. The moving air slams into a closed throttle body and pressure starts building. A moment later the bypass valves open and relieves this pressure build up. If the bypass valves did not open, the pressure would try to equalize back out through the turbos (this is why there are bypass valves) which is referred to as compressor surge.

The reason you do not see this with an external gauge is because those readings are taken from the intake manifold; after the throttle body. Once the throttle is closed, vacuum is created nearly immediately in the intake manifold and is reflected on an external gauge.

If this is still not clear, please do not post in a technical discussion as you are lacking the basic mechanical understanding required to be involved in these types of discussions.

Now on to the other potential issues; there are none. The logs are normal with taper up top. In fact, in one of the pulls boost dropped to below 10 PSI indicating a response to increased intake temperature readings; see the below plot.

[scalbert]

[cn555ic]

He is just one of those OPs that hates Vishnutuning and is a constant basher...No amount of reasoning or data will change his mind!

[sajakh]

Originally Posted by scalbert

If you are to post, please identify the issue being referred to.

As shown, the spikes are to be expected and occurred in every tune including stock. The only reason others do not see this is that there is no data logging is available with the other products.

But to clarify further for those who obviously cannot consider the specifics involved or may be lacking the thought processing capability:

The TMAP sensor, which is where the pressure readings come from, is located a couple of inches before the throttle body. When the throttle pedal is lifted the throttle closes (I suppose I need to be very specific for this crowd). Even though the throttle closed, the air is still moving inside the intake pipes. The moving air slams into a closed throttle body and pressure starts building. A moment later the bypass valves open and relieves this pressure build up. If the bypass valves did not open, the pressure would try to equalize back out through the turbos (this is why there are bypass valves) which is referred to as compressor surge.

The reason you do not see this with an external gauge is because those readings are taken from the intake manifold; after the throttle body. Once the throttle is closed, vacuum is created nearly immediately in the intake manifold and is reflected on an external gauge.

If this is still not clear, please do not post in a technical discussion as you are lacking the basic mechanical understanding required to be involved in these types of discussions.

Now on to the other potential issues; there are none. The logs are normal with taper up top. In fact, in one of the pulls boost dropped to below 10 PSI indicating a response to increased intake temperature readings; see the below plot.

Excellent explanation, as always scalbert.

Mods, please post this as a sticky to help avoid this unnecessary speculation and discussion. Thanks.

[e90AW335i]

Originally Posted by scalbert

The reason you do not see this with an external gauge is because those readings are taken from the intake manifold; after the throttle body. Once the throttle is closed, vacuum is created nearly immediately in the intake manifold and is reflected on an external gauge.

And what if you do see this on an external gauge Steve? Does that mean the engine is seeing that amount of boost shown on the gauge?

[scalbert]

Originally Posted by e90AW335i

And what if you do see this on an external gauge Steve? Does that mean the engine is seeing that amount of boost shown on the gauge?

That would be correct if the gauge's source is the intake manifold.

[e90AW335i]

Originally Posted by scalbert

That would be correct if the gauge's source is the intake manifold.

Which it would be if you tapped the vacuum lines going to the diverter valves.....

Thanks for the clarification, one more question. Is it dangerous to have a greater than 16psi boost spike seen by the motor if it is even for a split second?

[Panoz]

Originally Posted by cn555ic

He is just one of those OPs that hates Vishnutuning and is a constant basher...No amount of reasoning or data will change his mind!

Excuse me...that goes to whom?

[Panoz]

Originally Posted by scalbert

That would be correct if the gauge's source is the intake manifold.

That was actually my biggest consern...so every time we see a boost level like 15 to 15,2psi ,the actual boost is around 14,5psi.

Thanks everyone that helped me clarify this through this topic.

[e90AW335i]

Originally Posted by Panoz

That was actually my biggest consern...so every time we see a boost level like 15 to 15,2psi ,the actual boost is around 14,5psi.

Thanks everyone that helped me clarify this through this topic.

Get a boost gauge so you can know.

[hotrod182]

Originally Posted by e90AW335i

Get a boost gauge so you can know.

And let us know what the pressure differential actually is.

[cn555ic]

Originally Posted by Panoz

Excuse me...that goes to whom?

I was referring to G37killer!

[Panoz]

Originally Posted by hotrod182

And let us know what the pressure differential actually is.

Will certainly do as long as I find a gauge displaying psi... everything measures boost in "bar" here.

Rix ,
Any news for me??

[getInline]

Originally Posted by Panoz

Just for the record JB2HR was working at a rock solid 0,95 bar (14~14,5 psi) with no spikes and no boost varations while accelarating in different gears. Back to v3 now...

Not bashing here but how did you determine this? JB2HR doesn't have an logging capability so did you install a boost gauge? And if so, was it located before the throttle body like the TMAP sensor? Thx.

[e90AW335i]

Originally Posted by getInline

Not bashing here but how did you determine this? JB2HR doesn't have an logging capability so did you install a boost gauge? And if so, was it located before the throttle body like the TMAP sensor? Thx.

It was on a different car so maybe they had a boost gauge....

[Panoz]

Originally Posted by getInline

Not bashing here but how did you determine this? JB2HR doesn't have an logging capability so did you install a boost gauge? And if so, was it located before the throttle body like the TMAP sensor? Thx.

Ι've temporary installed a boost gauge (in bar ) to check how was working (used the vacum lines at the left side of the engine that goes to div.valves).

I had a co-driver checking it an commenting all the time how it was behaving.
It was really stable.

The discussion here is not about JB2HR vs V3....

I was just seeing v3 boosting 15,2 to 15,5 continiously and I piss my pants. Scalbert was kind enough to explain me that the Pde reader is showing higher boost than normal...so I'm a bit reliefed now (until placing a boost gauge in psi)

[scalbert]

Originally Posted by e90AW335i

Is it dangerous to have a greater than 16psi boost spike seen by the motor if it is even for a split second?

Depends but for the most part it is harmless. If this occured int he mid to low RPM range, the turbo is just fine as well as the engine. I really wouldn't want that up top but in the mid to low RPM range; no problem. Just FYI, Shiv could dial the maps to make 18 PSI around 3k revs with a taper to 11 - 12 PSI up top. That could provide tremedous torque but a very negative sloping torque curve.

[e90AW335i]

Originally Posted by scalbert

Depends but for the most part it is harmless. If this occured int he mid to low RPM range, the turbo is just fine as well as the engine. I really wouldn't want that up top but in the mid to low RPM range; no problem. Just FYI, Shiv could dial the maps to make 18 PSI around 3k revs with a taper to 11 - 12 PSI up top. That could provide tremedous torque but a very negative sloping torque curve.

Lets just say that someone saw a 18-20psi boost spike at 5500-6000rpm while shifting. This was seen on a boost gauge. Since this is in the upper rpm range doesn't this seem bad for the motor as well as the turbos?

Also, just because you can dial something to make 18psi doesn't mean you should. I honestly think 15.5psi is the max that we should push this turbos too. This is based purely on observing other tuning companys (Alpina (16psi), and Dinan (14psi)).