Will an R32 GTR with -9 turbos need a tune?

[Fizurg]

This is probably a stupid question, but i have a factory standard R32 GTR which has blown its standard turbos. i dont have a lot of money at the moment so its just sitting there doing nothing. if i replaced the factory turbos with -9s and ran factory boost would the car be safe to drive? an aftermarket ecu is on the cards in the future but sadly funds wont aloow it at the moment. 

[joshuaho96]

On 5/5/2022 at 8:43 PM, Fizurg said:

This is probably a stupid question, but i have a factory standard R32 GTR which has blown its standard turbos. i dont have a lot of money at the moment so its just sitting there doing nothing. if i replaced the factory turbos with -9s and ran factory boost would the car be safe to drive? an aftermarket ecu is on the cards in the future but sadly funds wont aloow it at the moment. 

It would be safe to drive on, but you'd want to avoid more than like 0.5 bar. Even at factory boost levels like 0.7 bar you could hit the final load column at which point you will lose something like 5-8 degrees of timing. I have GTIII-SS turbos on my car without a tune right now due to emissions reasons and just a single WOT pull caused a pretty strong smell in the exhaust like it wasn't doing good things to the catalytic converter. It definitely hit the last load cell and I believe the MAF hit something like 4V.

I am hoping to finish up my emissions issues soon so I can get started on ECU map development, then I can show people just how awful the HKS nuggets are.

[Fizurg]

cheers for the reply. just having it driveable would be nice. then i could take it to the tuners and have an ecu fitted and tuned when i have the money. how do you limit the boost to 0.5 bar?

[Duncan]

I agree, it could be OK. They only flow a little more air than standard, especially if boost is low and those early ECUs allowed a lot more leeway for small changes than later r series.

Most likely it will just blow black smoke (running rich, ECU adding too much fuel) as it comes onto boost. However, much worse would be if it does not add enough fuel for the extra air, in this case it will ping (sounds like rocks rattling in a tin), this can kill your engine very quickly

[Duncan]

You can't get less boost than the spring pressure on the turbo's wastegate. Most replacement turbos come with 0.8 or 1 bar.

You can stay off full boost by not keeping your foot at 100% as it comes on.

[Fizurg]

so i guess the main question is . am i better off having it driveable but not running properly or not driving at all?

also another question. where is the factory ecu? id like to leave then engine bay look factory and ive been told to use an Nistune as it looks factory but if something like a haltech will be better and be hidden anyway so it wont matter?

[Murray_Calavera]

A wastegate like this will allow you to adjust the boost by changing out the springs. This wastegate comes with a 7 psi spring which sounds like what your after. 

You can run various combinations of springs to have between 3 psi up to 26 psi.

https://www.turbosmart.com/product/iwg75-uni-150mm-actuator-7psi/

Not the cheapest option as you'd need to buy 2 of these things, but if your going to keep the -9 turbos, the extra adjustability of these wastegates is nice.  

[Murray_Calavera]

On 5/6/2022 at 2:17 PM, Fizurg said:

so i guess the main question is . am i better off having it driveable but not running properly or not driving at all?

also another question. where is the factory ecu? id like to leave then engine bay look factory and ive been told to use an Nistune as it looks factory but if something like a haltech will be better and be hidden anyway so it wont matter?

You could install the -9 turbos, turn the boost down and put it on the dyno to check the mixtures to ensure everything is safe. 

The haltech would be hidden behind the passenger side kick panel. If whoever is inspecting the car pulls that panel off, they would spot the aftermarket ecu. 

[Fizurg]

On 06/05/2022 at 4:22 PM, Murray_Calavera said:

You could install the -9 turbos, turn the boost down and put it on the dyno to check the mixtures to ensure everything is safe. 

The haltech would be hidden behind the passenger side kick panel. If whoever is inspecting the car pulls that panel off, they would spot the aftermarket ecu. 

Awesome, so no issues there then. 

I had planned to build the car with a lot more power and build the type of car i dreamed of as a teenager. but since buying it my partner has gotten pregnant and so spending money on toys has gotten slightly harder to justify. no i plan to ust get it back on the road and keep it as factory as possible, with only a few bolt ons. 

[joshuaho96]

On 5/5/2022 at 9:09 PM, Duncan said:

I agree, it could be OK. They only flow a little more air than standard, especially if boost is low and those early ECUs allowed a lot more leeway for small changes than later r series.

Most likely it will just blow black smoke (running rich, ECU adding too much fuel) as it comes onto boost. However, much worse would be if it does not add enough fuel for the extra air, in this case it will ping (sounds like rocks rattling in a tin), this can kill your engine very quickly

As far as I know the factory ECU up to the MAF/fuel flow limit will have a pretty reasonable AFR target, it's really just the pulling of timing to a pretty impressive extent that is a concern as it will spike EGTs. 

On 5/5/2022 at 9:07 PM, Fizurg said:

cheers for the reply. just having it driveable would be nice. then i could take it to the tuners and have an ecu fitted and tuned when i have the money. how do you limit the boost to 0.5 bar?

Either you put a 0.5 bar wastegate actuator in the turbo and unplug the electrical connector on the boost solenoid or don't press your foot too far down on the accelerator pedal. I currently have my turbos running wastegate spring pressure which is still too high (~0.88 bar) so I have to compensate by not metering a ton of air. Keep in mind that because of the ignition timing retard on the final load column you will actually have less power than if you had kept the airflow within the bounds. I only did it once to see what would happen and it was a split second, I was going to tell the driver to let off immediately if anything my Consult dashboard suggested looked bad like maxing out the MAF, excessive injector duty cycle, etc.

There was another thread recently about mounting something like a Haltech Elite in the factory position, I checked with the seller of a bracket and he posted pictures of it mounted in the factory position with the kick plate installed. Obviously if you add stuff like the WB1/etc you will have to figure out how to get all of that mounted as well: https://www.instagram.com/p/CX5YuEuKQSx/

[Dose Pipe Sutututu]

Another option is, get the turbos on, then get a Nistune ECU get it tuned OR get a Haltech Platinum Pro (not too expensive) unplug the AFMs/MAFs and feed a vacuum hose to the ECU and just use the base map (has crap all timing in it).

[Murray_Calavera]

On 5/6/2022 at 3:25 PM, Dose Pipe Sutututu said:

Another option is, get the turbos on, then get a Nistune ECU get it tuned OR get a Haltech Platinum Pro (not too expensive) unplug the AFMs/MAFs and feed a vacuum hose to the ECU and just use the base map (has crap all timing in it).

With the added benefit that the Nistune would let the OP keep is stock appearance as well. 

[GTSBoy]

Just Nistune the ECU first. Then replace turbos. Then connect laptop (and wideband) and drive it and make sure fuelling is good and timing is OK on the very first drive.

[Dose Pipe Sutututu]

On 06/05/2022 at 4:13 PM, GTSBoy said:

Just Nistune the ECU first. Then replace turbos.

but his standard turbos have already died, nek minnit PRP catalogue, block brace, G40-900 twin gates, Samsonas

[Fizurg]

On 6/5/2022 at 5:25 PM, Dose Pipe Sutututu said:

Another option is, get the turbos on, then get a Nistune ECU get it tuned OR get a Haltech Platinum Pro (not too expensive) unplug the AFMs/MAFs and feed a vacuum hose to the ECU and just use the base map (has crap all timing in it).

Would this really work? Also why won’t the MAFs work with an aftermarket ECU?

Edited May 6, 2022 by Fizurg

[joshuaho96]

On 5/6/2022 at 6:25 AM, Fizurg said:

Would this really work? Also why won’t the MAFs work with an aftermarket ECU?

Dual MAFs requires more analog inputs that most ECUs don’t have. This is on top of the fact that MAF tuning is wildly unpopular outside of OEM applications. Haltech is one of the few companies that supports the MAFs but you’re going to have to find someone that is actually willing to tune with MAFs. I need to test how the Haltech actually works with MAFs though. I plan on replicating the stock ECU map as much as possible on a Haltech Elite ECU but it’s blocked by registration issues. 

[Dose Pipe Sutututu]

On 06/05/2022 at 11:25 PM, Fizurg said:

Would this really work? Also why won’t the MAFs work with an aftermarket ECU?

You'll be stupid to use them, given you have the option of speed density with the Haltech not to mention the benefits of binning the MAFs modified FI cars.

[Duncan]

Nissan used AFMs rather than MAP sensors for a reason, it wasn't an accident. They might cause intake restrictions at very high power but they are excellent for things like cold start, atmospheric pressure adjustment etc.

Anyway, if you want the cheapest aftermarket ECU so you can tune it, a power fc is about 30-50% the cost of a haltech (500-800$), and the base map is usable without a tune in the short term.

[Dose Pipe Sutututu]

AFMs will always provide more accurate fueling, not going to deny that.

Hence on direct injected they actually use both MAP and AFMs/MAFs to determine load and all the other parameters.

[joshuaho96]

On 5/6/2022 at 1:40 PM, Duncan said:

Nissan used AFMs rather than MAP sensors for a reason, it wasn't an accident. They might cause intake restrictions at very high power but they are excellent for things like cold start, atmospheric pressure adjustment etc.

Anyway, if you want the cheapest aftermarket ECU so you can tune it, a power fc is about 30-50% the cost of a haltech (500-800$), and the base map is usable without a tune in the short term.

Something I've been thinking about for a while is why with ITBs everyone is still using pure TPS in certain cases instead of throttle mass flow or something like that. It seems insane to me to tune based on a variable that doesn't actually represent engine load. There's so many accessories that will change their load significantly, atmospheric compensation, gearing/road load, etc. The factory intake manifold already has the post-TB port on the back of the balance tube, all you need at that point is to put a pressure sensor in the plenum/intake manifold collector off the AAC valve pipe for example. At which point the delta pressure across the throttle body combined with throttle position should be able to generate an estimated g/s flow rate.

I still plan on using MAFs anyways but if Haltech ever implements throttle mass flow I would probably consider actually switching over as it's pretty crazy just how much piping is between the MAF sensor and the intake valve from the factory.