Jump to content
SAU Community

Recommended Posts

I recently added some more power to my R35, whilst it was great for simple straight line stuff (running 11.1 @ 125mph at WSID) i found that my circuit laps times have actually gone backwards (!).

My conclusion: the extra power is inducing VDC/Traction Control "events" (wheel slip) and pulling power.

Background: If you've ever forgotten to put your R35 in 'R' mode on the circuit, you will have noticed/heard/felt the system working each corner of the car, with the threshold of slip being rather pessimistic. However put the car into 'R' mode - the system then allows a higher degree of slip & yaw, less instrusive & better laps times, and more fun...

Anyway, with the aftermarket tune - say +60rwkw - 'R' mode seems like 'non-R' mode used to! (on the circuit anyway). I think the extra power is overwhelming the delicately tuned 'R' mode thresholds built into the VDC calibration.

So... consider this a heads up! Adding gobbs of power isnt going to immediately translate into quicker lap times. Unless you're comfortable turning VDC off, and driving the thing on your wits alone.

The sprint series i am in doesnt allow aftermmarket tunes, so i need to remove the tune anyway (for this coming weekend) but i thought this might spark some debate on the matter. Perhaps some others have tried adding significsant power to the R35, very interested in your thoughts (in a circuit racing context).

Edited by LSX-438
Link to comment
https://www.sau.com.au/forums/topic/286808-r35-circuit-work-and-more-power/
Share on other sites

Driver tuition is your answer to better lap times, not more power!

Driver training is probably never a bad thing, especially for amateurs like myself. But i dont think that's the primary issue here. It sure is easy/tempting to suggest that though; most people that have not driven the R35 on the track think it drives itself. That's probably true to an extent... up to about 80% of the cars potential.

That extra 10 to 20% isnt a cake walk.

Anyway, with normal power, in R mode, on the track, with RE55's, i don't feel VDC kick in, ever - unless i've made a huge error. However with (significantly) more power, it seems to break loose much more easily. Extra slip isnt necessary a bad thing, in fact i reckon a certain percetage of slip is required for the absolute quickest times (dependig on tyres). However the VDC calibration only allows so much slip. No amount of tuition is going to get around this - it's a hardware/calibration issue.

The answer is, be content with standard power OR be prepared to turn VDC (and your warranty) OFF. It's probably a non-issue, given anyone running a tune probably doesnt have a warranty anyway. This is just a heads up/fyi for R35 owners, and what to expect when you add gobbs of power :)

Edited by LSX-438

I actually noticed the increase intervantion of the stability control even with just the Midpipe added. In R mode I am getting it come in more than I did before.

I have not tracked since the mid pipe was installed however I have a day planned in about 3 weeks so I can finish of the Bridgestones before the Dunlops go on.

It is an interesting point you have raised Duncan and I am curious now.

Cheers

This is a fairly common trait in newer vehicles equiped with stability control (and importantly torque limiting protocols). Adding more power often leads to excessive interuptions, whether it be a tow vehicle or race car, and could possibly lead to a slower lap.

My suggestion would be to switch it all off.

This is a fairly common trait in newer vehicles equiped with stability control (and importantly torque limiting protocols). Adding more power often leads to excessive interuptions, whether it be a tow vehicle or race car, and could possibly lead to a slower lap.

My suggestion would be to switch it all off.

You can end up very very sideways with it switched off

Believe me I know

90 degrees to the track at Winton in the sweeper

lol, come on Jeff, you can end up sideways in anything if you fluff it up mate :woot:

We did last year's Tassie Tarmac Challenge (Rally Burnie) with it all off in some real grotty conditions and only took it off road twice ;)

Edited by Marlin

This leads me to a question i should know the answer for... when you turn VDC off, what exactly is turned off? Is it just the traction control mechnaism? What about torque split (front vs rear) and god know's whatever else is in the system?

yeah turning it off is the only answer. even in R mode with more power you will be cutting in the traction control/stability control often and it will slow your times.

I have driven standard R35 on track and upgraded (exhaust, ecu etc) and prefer VDC to OFF. yes you will find yourself dealing with some power oversteer but its very controlable if you know how to use throttle and opposite lock (and I'm sure you do mate).

it's not like it becomes a scary unbalanced car when you turn VDC off. the chassis is great, it still has loads of grip and the active torque split is still working as it should. just no traction control will cut in no matter how sideways you get it. but I honestly reckon you would have to actually try to spin one off the track. they are very controlable in a slide and you can easily balance the car on the throttle. and it's fun. :woot:

Its one thing to sit here and tell you how to drive....but from what I know you already have more than a good handle on that.

The answer lays in something else, and thats the ability of the turbocharger system of the GTR to unbalance the car. If you stand on the throttle at the wrong point of the corner in a GTR its easy to unbalance the car, even slightly step the tail out, and lose time. VDC-R isnt so much the problem, but the ability of the car to change direction and correct for a rapid shift in lateral G-Force really is! The key is to be as smooth and progressive as possible, with the fastest lap times coming to the calmest driver :banana:

This is why when I custom tune a GTR for the track I do this -

customtune.jpg

Notice that the boost curve progressively pulls away from stock and then only by a psi or so from 4200 (thats over an off the shelf Stage II Cobb tune). The key to giving a GTR more power AND improving lap times is by minimising the throttle-on imbalance of the car and keeping the power curve as linear and 'spike free' as possible. This is difficult with an airflow based wastegate duty cycle table (as the GTR has from the factory), so we spend many hours developing wastegate control maps that keep boost spikes out of full throttle upshift and keep the GTR balanced on the exit and transition :(

This is not saying the way anyone else does it is wrong. There are some out there in Aus that seem to have a good handle on the GTR and reflashing. Just this way is how we do it after spending a few hundred laps trying different things in our own R35 :)

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • I did end up getting it sorted, as GTSBoy said, there was a corroded connection and wire that needed to be replaced. I ended up taking out the light assembly, giving everything a good clean and re-soldered the old joints, and it came out good.
    • Wow, thanks for your help guys 🙏. I really appreciate it. Thanks @Rezz, if i fail finding any new or used, full or partial set of original Stage carpets i will come back to you for sure 😉 Explenation is right there, i just missed it 🤦‍♂️. Thanks for pointing out. @soviet_merlin in the meantime, I received a reply from nengun, and i quote: "Thanks for your message and interest in Nengun. KG4900 is for the full set of floor mats, while KG4911 is only the Driver's Floor Mat. FR, RH means Front Right Hand Side. All the Full Set options are now discontinued. However, the Driver's Floor Mat options are still available according to the latest information available to us. We do not know what the differences would be, but if you only want the one mat, we can certainly see what we can find out for you". Interesting. It seems they still have some "new old stock" that Duncan mentioned 🤔. I wonder if they can provide any photos......And i also just realized that amayama have G4900 sets. I'm tempted too. 
    • Any update on this one? did you manage to get it fixed?    i'm having the same issue with my r34 and i believe its to do with the smart entry (keyless) control module but cant be sure without forking out to get a replacement  
    • So this being my first contribution to the SAU forums, I'd like to present and show how I had to solve probably one of the most annoying fixes on any car I've owned: replacing a speedometer (or "speedo") sensor on my newly acquired Series 1 Stagea 260RS Autech Version. I'm simply documenting how I went about to fix this issue, and as I understand it is relatively rare to happen to this generation of cars, it is a gigantic PITA so I hope this helps serve as reference to anyone else who may encounter this issue. NOTE: Although I say this is meant for the 260RS, because the gearbox/drivetrain is shared with the R33 GTR with the 5-speed manual, the application should be exactly the same. Background So after driving my new-to-me Stagea for about 1500km, one night while driving home the speedometer and odometer suddenly stopped working. No clunking noise, no indication something was broken, the speedometer would just stop reading anything and the odometer stopped going up. This is a huge worry for me, because my car is relatively low mileage (only 45k km when purchased) so although I plan to own the car for a long time, a mismatched odometer reading would be hugely detrimental to resale should the day come to sell the car. Thankfully this only occurred a mile or two from home so it wasn't extremely significant. Also, the OCD part of me would be extremely irked if the numbers that showed on my dash doesn't match the actual ageing of the car. Diagnosing I had been in communication with the well renown GTR shop in the USA, U.P.garage up near University Point in Washington state. After some back and forth they said it could be one of two things: 1) The speedometer sensor that goes into the transfer case is broken 2) The actual cluster has a component that went kaput. They said this is common in older Nissan gauge clusters and that would indicate a rebuild is necessary. As I tried to figure out if it was problem #1, I resolved problem #2 by sending my cluster over to Relentless Motorsports in Dallas, TX, whom is local to me and does cluster and ECU rebuilds. He is a one man operation who meticulously replaces every chip, resistor, capacitor, and electronic component on the PCB's on a wide variety of classic and modern cars. His specialty is Lexus and Toyota, but he came highly recommended by Erik of U.P.garage since he does the rebuilds for them on GTR clusters.  For those that don't know, on R32 and R33 GTR gearboxes, the speedometer sensor is mounted in the transfer case and is purely an analog mini "generator" (opposite of an alternator essentially). Based on the speed the sensor spins it generates an AC sine wave voltage up to 5V, and sends that via two wires up to the cluster which then interprets it via the speedometer dial. The signal does NOT go to the ECU first, the wiring goes to the cluster first then the ECU after (or so I'm told).  Problems/Roadblocks I first removed the part from the car on the underside of the transfer case (drain your transfer case fluid/ATF first, guess who found out that the hard way?), and noted the transfer case fluid was EXTREMELY black, most likely never changed on my car. When attempting to turn the gears it felt extremely gritty, as if something was binding the shaft from rotating properly. I got absolutely no voltage reading out of the sensor no matter how fast I turned the shaft. After having to reflow the solder on my AFM sensors based on another SAU guide here, I attempted to disassemble the silicone seal on the back of the sensor to see what happened inside the sensor; turns out, it basically disintegrated itself. Wonderful. Not only had the electrical components destroyed themselves, the magnetic portion on what I thought was on the shaft also chipped and was broken. Solution So solution: find a spare part right? Wrong. Nissan has long discontinued the proper sensor part number 32702-21U19, and it is no longer obtainable either through Nissan NSA or Nissan Japan. I was SOL without proper speed or mileage readings unless I figured out a way to replace this sensor. After tons of Googling and searching on SAU, I found that there IS however a sensor that looks almost exactly like the R33/260RS one: a sensor meant for the R33/R34 GTT and GTS-T with the 5 speed manual. The part number was 25010-21U00, and the body, plug, and shaft all looked exactly the same. The gear was different at the end, but knowing the sensor's gear is held on with a circlip, I figured I could just order the part and swap the gears. Cue me ordering a new part from JustJap down in Kirrawee, NSW, then waiting almost 3 weeks for shipping and customs clearing. The part finally arrives and what did I find? The freaking shaft lengths don't match. $&%* I discussed with Erik how to proceed, and figuring that I basically destroyed the sensor trying to get the shaft out of the damaged sensor from my car. we deemed it too dangerous to try and attempt to swap shafts to the correct length. I had to find a local CNC machinist to help me cut and notch down the shaft. After tons of frantic calling on a Friday afternoon, I managed to get hold of someone and he said he'd be able to do it over half a week. I sent him photos and had him take measurements to match not only the correct length and notch fitment, but also a groove to machine out to hold the retentive circlip. And the end result? *chef's kiss* Perfect. Since I didn't have pliers with me when I picked up the items, I tested the old gear and circlip on. Perfect fit. After that it was simply swapping out the plug bracket to the new sensor, mount it on the transfer case, refill with ATF/Nissan Matic Fluid D, then test out function. Thankfully with the rebuilt cluster and the new sensor, both the speedometer and odometer and now working properly!   And there you have it. About 5-6 weeks of headaches wrapped up in a 15 minute photo essay. As I was told it is rare for sensors of this generation to die so dramatically, but you never know what could go wrong with a 25+ year old car. I HOPE that no one else has to go through this problem like I did, so with my take on a solution I hope it helps others who may encounter this issue in the future. For the TL;DR: 1) Sensor breaks. 2) Find a replacement GTT/GTS-T sensor. 3) Find a CNC machinist to have you cut it down to proper specs. 4) Reinstall then pray to the JDM gods.   Hope this guide/story helps anyone else encountering this problem!
    • So this being my first contribution to the SAU forums, I'd like to present and show how I had to solve probably one of the most annoying fixes on any car I've owned: replacing a speedometer (or "speedo") sensor on my newly acquired Series 1 Stagea 260RS Autech Version. I'm simply documenting how I went about to fix this issue, and as I understand it is relatively rare to happen to this generation of cars, it is a gigantic PITA so I hope this helps serve as reference to anyone else who may encounter this issue. NOTE: Although I say this is meant for the 260RS, because the gearbox/drivetrain is shared with the R33 GTR with the 5-speed manual, the application should be exactly the same. Background So after driving my new-to-me Stagea for about 1500km, one night while driving home the speedometer and odometer suddenly stopped working. No clunking noise, no indication something was broken, the speedometer would just stop reading anything and the odometer stopped going up. This is a huge worry for me, because my car is relatively low mileage (only 45k km when purchased) so although I plan to own the car for a long time, a mismatched odometer reading would be hugely detrimental to resale should the day come to sell the car. Thankfully this only occurred a mile or two from home so it wasn't extremely significant. Also, the OCD part of me would be extremely irked if the numbers that showed on my dash doesn't match the actual ageing of the car. Diagnosing I had been in communication with the well renown GTR shop in the USA, U.P.garage up near University Point in Washington state. After some back and forth they said it could be one of two things: 1) The speedometer sensor that goes into the transfer case is broken 2) The actual cluster has a component that went kaput. They said this is common in older Nissan gauge clusters and that would indicate a rebuild is necessary. As I tried to figure out if it was problem #1, I resolved problem #2 by sending my cluster over to Relentless Motorsports in Dallas, TX, whom is local to me and does cluster and ECU rebuilds. He is a one man operation who meticulously replaces every chip, resistor, capacitor, and electronic component on the PCB's on a wide variety of classic and modern cars. His specialty is Lexus and Toyota, but he came highly recommended by Erik of U.P.garage since he does the rebuilds for them on GTR clusters.  For those that don't know, on R32 and R33 GTR gearboxes, the speedometer sensor is mounted in the transfer case and is purely an analog mini "generator" (opposite of an alternator essentially). Based on the speed the sensor spins it generates an AC sine wave voltage up to 5V, and sends that via two wires up to the cluster which then interprets it via the speedometer dial. The signal does NOT go to the ECU first, the wiring goes to the cluster first then the ECU after (or so I'm told).  Problems/Roadblocks I first removed the part from the car on the underside of the transfer case (drain your transfer case fluid/ATF first, guess who found out that the hard way?), and noted the transfer case fluid was EXTREMELY black, most likely never changed on my car. When attempting to turn the gears it felt extremely gritty, as if shttps://imgur.com/6TQCG3xomething was binding the shaft from rotating properly. After having to reflow the solder on my AFM sensors based on another SAU guide here, I attempted to disassemble the silicone seal on the back of the sensor to see what happened inside the sensor; turns out, it basically disintegrated itself. Wonderful. Not only had the electrical components destroyed themselves, the magnetic portion on what I thought was on the shaft also chipped and was broken. Solution So solution: find a spare part right? Wrong. Nissan has long discontinued the proper sensor part number 32702-21U19, and it is no longer obtainable either through Nissan NSA or Nissan Japan. I was SOL without proper speed or mileage readings unless I figured out a way to replace this sensor. After tons of Googling and searching on SAU, I found that there IS however a sensor that looks almost exactly like the R33/260RS one: a sensor meant for the R33/R34 GTT and GTS-T with the 5 speed manual. The part number was 25010-21U00, and the body, plug, and shaft all looked exactly the same. The gear was different at the end, but knowing the sensor's gear is held on with a circlip, I figured I could just order the part and swap the gears. Cue me ordering a new part from JustJap down in Kirrawee, NSW, then waiting almost 3 weeks for shipping and customs clearing. The part finally arrives and what did I find? The freaking shaft lengths don't match. $&%* I discussed with Erik how to proceed, and figuring that I basically destroyed the sensor trying to get the shaft out of the damaged sensor from my car. we deemed it too dangerous to try and attempt to swap shafts to the correct length. I had to find a local CNC machinist to help me cut and notch down the shaft. After tons of frantic calling on a Friday afternoon, I managed to get hold of someone and he said he'd be able to do it over half a week. I sent him photos and had him take measurements to match not only the correct length and notch fitment, but also a groove to machine out to hold the retentive circlip. And the end result? *chef's kiss* Perfect. Since I didn't have pliers with me when I picked up the items, I tested the old gear and circlip on. Perfect fit. After that it was simply swapping out the plug bracket to the new sensor, mount it on the transfer case, refill with ATF/Nissan Matic Fluid D, then test out function. Thankfully with the rebuilt cluster and the new sensor, both the speedometer and odometer and now working properly!   And there you have it. About 5-6 weeks of headaches wrapped up in a 15 minute photo essay. As I was told it is rare for sensors of this generation to die so dramatically, but you never know what could go wrong with a 25+ year old car. I HOPE that no one else has to go through this problem like I did, so with my take on a solution I hope it helps others who may encounter this issue in the future. For the TL;DR: 1) Sensor breaks. 2) Find a replacement GTT/GTS-T sensor. 3) Find a CNC machinist to have you cut it down to proper specs. 4) Reinstall then pray to the JDM gods.   Hope this guide/story helps anyone else encountering this problem!
×
×
  • Create New...