R35 GTR

[kevin p]

Hi,

Are you guys working on a platform for the Nissan R35 GTR?

 

Thanks  

 

[Vaughan]

Not at the moment. It would mostly be an exercise in replicating the factory CAN bus to an appropriate level such that the transmission, dash cluster and DSC to work correctly. Quick look at pictures on google doesn't show anything particularly special other than that the dual plenums with no noticeable balancing between them (maybe there is some connection where the rib in the center is) could cause issues with tuning where the two halves of the engine could be seeing different loads and might require separate boost control PID loops. The whole separated manifolds for each bank thing is a massive ball-ache when it comes to deciding how much to separate the two, do you run two distinct MAP sensors and do all the fuel and ignition calculations twice and which MAP value do you use for other logic such as engine protection and how do you apply cuts if one half of the engine is behaving but the other half isn't etc.

[dx4picco]

Vaughan, to my knowledge there is a bridge pipe, maybe like 20mm diameter at the back of the stock upper intake manifold to link both banks. 

[kevin p]

There is no balance tube, the engine uses 2 map sensors. One for each bank and there is also a T-map sensor as well. A single PID controls the boost. As for fuel and timing, one map controls both banks.  

 

 

[Vaughan]

1 hour ago, kevin p said:

There is no balance tube, the engine uses 2 map sensors. One for each bank and there is also a T-map sensor as well. A single PID controls the boost. As for fuel and timing, one map controls both banks.

one map run twice so each bank has its fuel and timing calculated for it or the same fuel and timing applied to both?

[Rossobianconero]

On 3/7/2024 at 8:58 AM, Vaughan said:

one map run twice so each bank has its fuel and timing calculated for it or the same fuel and timing applied to both?

at least on the tuning side, you have only one ignition and fuel table (more in reality but, lets keep it simple ) , but the closeloop is per bank and it will correct each bank as it sees necessary. Can not remember at the moment if you can adjust each bank on the stock ecu, like putting more timing on one cylinder that other but I would say probably, but timing is running the same base for both as the fuel, but runs full time closeloop per bank.

[Vaughan]

7 minutes ago, Rossobianconero said:

at least on the tuning side, you have only one ignition and fuel table (more in reality but, lets keep it simple ) , but the closeloop is per bank and it will correct each bank as it sees necessary. Can not remember at the moment if you can adjust each bank on the stock ecu, like putting more timing on one cylinder that other but I would say probably, but timing is running the same base for both as the fuel, but runs full time closeloop per bank.

I would be curious to see how the factory ECU deals with a significantly different pressure for one bank than the other

[kevin p]

Ok, what can I do to help? 

[Vaughan]

In terms of figuring out if it does the equation twice (once per bank) or if it does it once and then does closed loop corrections if you can see ignition numbers per bank or per cylinder then maybe find a way to let more air into one bank's manifold than the other (crack one throttle more) and see if each bank's ignition timing follows the same value form the ignition table or if each bank has significantly different ignition numbers implying that they are being pulled from different parts of the ignition table. Basically need an imbalance to see how it deals with it.

In terms of CAN integration we will most likely need to source a car locally in Christchurch NZ or Auckland NZ and spend a significant amount of time decoding the CAN for it.

[pugsparked]

They are joined at the rear of the manifold, only one solenoid to control 2 wg.

Reading the maf is where you will really see if there are differences in the turbos.