High End Burble

[SLIXK]

Custom 3 inched my car a few weeks ago and when I go for a boost the car burbles around 7k+ rpm range and loses a bit of power don’t think it did that before.. Any ideas or similar experiences. Do I need an ecu and tune?

[Ben C34]

How much boost are you running? I assume stock ecu?

[SLIXK]

On 11/28/2021 at 9:45 PM, Ben C34 said:

How much boost are you running? I assume stock ecu?

Stock turbo with no boost solenoid and stock ecu 

[joshuaho96]

On 11/28/2021 at 12:07 PM, SLIXK said:

Stock turbo with no boost solenoid and stock ecu 

If the car is overboosting it will hit an R&R corner of the map. The calibration engineers set up the map so that as you exceed the load expected by the stock turbo the engine will run noticeably rich and pull ignition timing. I believe there is also protection if you exceed the airflow the MAFs can read.

[SLIXK]

On 11/29/2021 at 10:37 AM, joshuaho96 said:

If the car is overboosting it will hit an R&R corner of the map. The calibration engineers set up the map so that as you exceed the load expected by the stock turbo the engine will run noticeably rich and pull ignition timing. I believe there is also protection if you exceed the airflow the MAFs can read.

How am I over boosting with just a 3 inch exhaust 

[GTSBoy]

On 11/29/2021 at 8:30 AM, SLIXK said:

How am I over boosting with just a 3 inch exhaust

Consider it to mean "more boost than the factory ECU tune is happy with". It is exactly as Joshua said. The high load high rpm corner of the factory maps are both grossly rich and very retarded. If your bigger exhaust is allowing a little more gas to flow, you will go deeper into that region and experience more of it.

[joshuaho96]

On 11/28/2021 at 2:00 PM, SLIXK said:

How am I over boosting with just a 3 inch exhaust 

If you have a Nistune you can read the TP load index, if you're hitting 88 that means you've reached the limits of the stock map. Maybe you have a very high RPM/load misfire that is going to get worse but it could also be that you need a slight remap.

[SLIXK]

On 11/29/2021 at 11:52 AM, joshuaho96 said:

If you have a Nistune you can read the TP load index, if you're hitting 88 that means you've reached the limits of the stock map. Maybe you have a very high RPM/load misfire that is going to get worse but it could also be that you need a slight remap.

Can my stock auto ecu be remapped?

 

On 11/29/2021 at 11:43 AM, GTSBoy said:

Consider it to mean "more boost than the factory ECU tune is happy with". It is exactly as Joshua said. The high load high rpm corner of the factory maps are both grossly rich and very retarded. If your bigger exhaust is allowing a little more gas to flow, you will go deeper into that region and experience more of it.

So basically I need a tunable ecu ?

[joshuaho96]

On 11/28/2021 at 3:09 PM, SLIXK said:

Can my stock auto ecu be remapped?

 

So basically I need a tunable ecu ?

I forgot which section of the forum I'm in. If you have a WC34 S2 with a JECS ECU then it can be remapped with Nistune. Load index maxing out at 88 is an RB26 thing, not RB25.

[SLIXK]

On 11/29/2021 at 12:14 PM, joshuaho96 said:

I forgot which section of the forum I'm in. If you have a WC34 S2 with a JECS ECU then it can be remapped with Nistune. Load index maxing out at 88 is an RB26 thing, not RB25.

If I go with nistune am I able to change my ecu to a link at a later stage or is the nistune a permanent mod?

[joshuaho96]

On 11/28/2021 at 4:07 PM, SLIXK said:

If I go with nistune am I able to change my ecu to a link at a later stage or is the nistune a permanent mod?

The Nistune is a daughterboard that attaches to the OEM board. The Nistune Type 4 WC34 JECS board uses your OEM Consult port to connect to a tuner's laptop rather than cutting a hole in the ECU case for a USB port. So it is a fully reversible mod, especially when it comes to changing your ECU out for a Link standalone. There is no point in bothering to revert your ECU back to factory condition once you get a Nistune installed though, if you want the factory ECU map you can just flash it at any time and it will work just like factory. The only difference is unlike the OEM ECU you can see even more live diagnostic data. You will lose some conformal coating on the OEM ECU board in order to get to the solder joints so don't drop water on your ECU for any reason after that unless you apply new coating.

Tuning Nistune requires a different approach to how you would tune something like a Link, both because you're dealing with what is effectively compiled code (how the ECU does the math) and because the ECU uses MAF primarily as the load scaler. Most people are unfamiliar with how MAFs work.

[GTSBoy]

On 11/29/2021 at 12:21 PM, joshuaho96 said:

Tuning Nistune requires a different approach to how you would tune something like a Link

Hardly. Load is load.

[SLIXK]

On 11/29/2021 at 2:51 PM, joshuaho96 said:

The Nistune is a daughterboard that attaches to the OEM board. The Nistune Type 4 WC34 JECS board uses your OEM Consult port to connect to a tuner's laptop rather than cutting a hole in the ECU case for a USB port. So it is a fully reversible mod, especially when it comes to changing your ECU out for a Link standalone. There is no point in bothering to revert your ECU back to factory condition once you get a Nistune installed though, if you want the factory ECU map you can just flash it at any time and it will work just like factory. The only difference is unlike the OEM ECU you can see even more live diagnostic data. You will lose some conformal coating on the OEM ECU board in order to get to the solder joints so don't drop water on your ECU for any reason after that unless you apply new coating.

Tuning Nistune requires a different approach to how you would tune something like a Link, both because you're dealing with what is effectively compiled code (how the ECU does the math) and because the ECU uses MAF primarily as the load scaler. Most people are unfamiliar with how MAFs work.

 Sweet so my auto ecu will be taken out for a stand alone like link so I don’t need to worry about reverting the nistune ?

[SLIXK]

On 11/29/2021 at 5:31 PM, SLIXK said:

 Sweet so my auto ecu will be taken out for a stand alone like link so I don’t need to worry about reverting the nistune ?

 

On 11/29/2021 at 2:51 PM, joshuaho96 said:

The Nistune is a daughterboard that attaches to the OEM board. The Nistune Type 4 WC34 JECS board uses your OEM Consult port to connect to a tuner's laptop rather than cutting a hole in the ECU case for a USB port. So it is a fully reversible mod, especially when it comes to changing your ECU out for a Link standalone. There is no point in bothering to revert your ECU back to factory condition once you get a Nistune installed though, if you want the factory ECU map you can just flash it at any time and it will work just like factory. The only difference is unlike the OEM ECU you can see even more live diagnostic data. You will lose some conformal coating on the OEM ECU board in order to get to the solder joints so don't drop water on your ECU for any reason after that unless you apply new coating.

Tuning Nistune requires a different approach to how you would tune something like a Link, both because you're dealing with what is effectively compiled code (how the ECU does the math) and because the ECU uses MAF primarily as the load scaler. Most people are unfamiliar with how MAFs work.

When I upgrade to link that is hah

[joshuaho96]

On 11/28/2021 at 6:35 PM, GTSBoy said:

Hardly. Load is load.

You have a point there, but the finer points of how the sensors work tends to be a reason why tuners don't like MAF-based tuning. The old hot wire sensors will see weird behavior in transients that requires min/max clamping. Card style hot film is better about reversion but the other issues still apply. There's also all the fun stuff that comes with MAFs on heavily modified intakes, usually OEM engineers sweat those details so there aren't weird issues causing a lot of noise in the MAF signal, etc...

I've talked to a number of tuners and even Haltech USA tells me nobody seems to care about MAF support in their ECUs, so they don't really have a lot of experience there. Link support will also say similar things, their near-universal advice is run speed density on their ECUs because tuners don't really use the MAF support so they don't put much effort into maintaining it properly.

Personally I don't care, if the factory setup is MAF and after thinking hard on the tradeoffs MAFs still make sense then I'll do whatever it takes to make it run properly, but I don't think that's how most tuners operate.

On 11/28/2021 at 8:31 PM, SLIXK said:

 Sweet so my auto ecu will be taken out for a stand alone like link so I don’t need to worry about reverting the nistune ?

Yes, there's no need to revert a Nistune mod. Personally I would keep it even after switching to a Link as a diagnostic tool while developing a base map properly.

Edited November 29, 2021 by joshuaho96

[GTSBoy]

On 11/29/2021 at 4:47 PM, joshuaho96 said:

Personally I don't care, if the factory setup is MAF and after thinking hard on the tradeoffs MAFs still make sense then I'll do whatever it takes to make it run properly, but I don't think that's how most tuners operate.

Once you're into "the AFM is suffering from reversion, etc" territory, it's time to slip the card type AFM into the cooler pipework and just sidestep all that old bullshit. We're >10 years into the new world of possibilities offered by the new AFMs.

[SLIXK]

Doesn’t burble anymore once I chucked in split fires and new spark plugs and fixed leaking bov