The ever evolving R32 GTR build

[mr_rbman]

New battery sourced, thank @BK and @Dose Pipe Sutututu

On special at Autobarn too so win win...

The guy at Autobarn saw that I was replacing my Optima with this and said I was nuts going from an Optima to a Supercharge, haha

[Dose Pipe Sutututu]

Smart nuts, cheaper (cost wise), local and longer warranty.

Seems pretty not nuts to me lol

[mr_rbman]

Had an update call from the tuner today.

98 tune is all complete...

Made 378rwkws on wastegate pressure (16-17psi from memory)

not bhed...

[Dose Pipe Sutututu]

Very nice, yashimash 

[mr_rbman]

Ended up making 430rwkws on E85 at just 20 psi.

Having alternator issues (not the limiting factor I was expecting)..

Tuner says it's still got more in it with a new alternator so looking into the LS1 conversion...

...Not heaps though as the small rear wheel is just beginning to restrict things and potentially my small pod filter too....

[Dose Pipe Sutututu]

Looking very good, twins in the bin 🥰

[BK]

8 hours ago, mr_rbman said:

Ended up making 430rwkws on E85 at just 20 psi.

Having alternator issues (not the limiting factor I was expecting)..

Tuner says it's still got more in it with a new alternator so looking into the LS1 conversion...

...Not heaps though as the small rear wheel is just beginning to restrict things and potentially my small pod filter too....

Alternator limiting how ? I smell bullshit...

Coils and fuel pumps are your most power hungry things and I'd expect dramas very early in the tuning process if this was the case from a alternator causing a low voltage condition.

[Ben C34]

Good idea putting an ls1 engine in. That will sort it

 

[mr_rbman]

On 2/2/2023 at 10:24 PM, BK said:

Alternator limiting how ? I smell bullshit...

Coils and fuel pumps are your most power hungry things and I'd expect dramas very early in the tuning process if this was the case from a alternator causing a low voltage condition.

mmmm, interesting...

This side of things (electrical) goes over my head so I just took him at his word...

I'll have a chat to him next week to get a clearer understanding...

[mr_rbman]

[r32-25t]

if the alternator can’t keep up and the voltage drops then it slows the fuel pumps slow down and can’t supply their full potential along with a list of many other things it does to the tune 

[Dose Pipe Sutututu]

Or he's getting misfires with more boost because the voltages are subpar and his coils aren't producing the required spark.

I've experienced this, hence I have a relatively new 90AMP Circuit Sports alternator in my car.

 

[BK]

3 hours ago, r32-25t said:

if the alternator can’t keep up and the voltage drops then it slows the fuel pumps slow down and can’t supply their full potential along with a list of many other things it does to the tune 

Like I said, the low voltage condition from an alternator will mainly affect fuel pump and coil operation but it has to be pretty severe to do that, injectors draw stuff all by comparison. Coils would start misfiring and you would start to have low fuel pressure lean outs, but the fact it supported enough for well over 400kw with stable AFR and no jittery power curve from misfies uptop doesn't really point to coils misfiring or low fuel pressure from the alternator limiting things at all. My point is you will see something more sinister happening well before you get to tune the thing properly.

4 hours ago, mr_rbman said:

mmmm, interesting...

This side of things (electrical) goes over my head so I just took him at his word...

I'll have a chat to him next week to get a clearer understanding...

Now don't get me wrong, having a more capable alternator with more headroom is always a good thing. I myself went from the stock 90A to an ARD 140A as I could see I was  getting only 12v at battery with all 3 fuel pumps running at idle under test conditions and would cause dramas. The ARD jumped it back to about 14.3v at full load at around 70A. End of the day a better alternator is never a bad thing, just usually not a likely thing if everything else checks out.

1 hour ago, Dose Pipe Sutututu said:

Or he's getting misfires with more boost because the voltages are subpar and his coils aren't producing the required spark.

I've experienced this, hence I have a relatively new 90AMP Circuit Sports alternator in my car.

 

If this is the case you don't need to be at full load to see if something doesn't look right as your voltages even at idle will be a bit suspect.

[Dose Pipe Sutututu]

1 hour ago, BK said:

this is the case you don't need to be at full load to see if something doesn't look right as your voltages even at idle will be a bit suspect.

Yes that is also true however it's not the first thing you look at when you're tuning.

Generally you'll interrogate voltages when things don't go as expected or planned, e.g. a misfire or sensors doing cooked shit lol

[BK]

 

22 minutes ago, Dose Pipe Sutututu said:

Yes that is also true however it's not the first thing you look at when you're tuning.

Generally you'll interrogate voltages when things don't go as expected or planned, e.g. a misfire or sensors doing cooked shit lol

I get where you're coming from, but establishing the very important basics with things like what baseline voltages are at battery and fuel pump terminals, fuel pressure, base timing, spark plug type and gap and so on should be a given as a precheck before going anywhere near a dyno.

Going on a dyno to tune without doing any of this with something like say less than 13.0v at pump terminals or god forbid actually at the battery is just asking for tuners to crack the shits, as that will immediately flag potential problems elsewhere. i also accept unforseen things happen that can't be picked up until actually exposed on the dyno too, which is why the are such a great tool.

I notice a lot of places are asking for dyno prechecks to avoid exactly this sort of thing.

[mr_rbman]

so what should i do (from home) to eliminate other issues or potentially confirm that the alternator isn't up to the task?

[Ben C34]

On 2/5/2023 at 5:30 PM, mr_rbman said:

so what should i do (from home) to eliminate other issues or potentially confirm that the alternator isn't up to the task?

Measure voltage at the battery, and voltage at the pump .

You can get multimeter that log over bluetooth pretty cheap from jaycar. Then you can see what us happening under load. 

 

I cant recall what ecu you are running, but it should be able to log its own voltage if it is any good.

[mr_rbman]

1 hour ago, Ben C34 said:

Measure voltage at the battery, and voltage at the pump .

You can get multimeter that log over bluetooth pretty cheap from jaycar. Then you can see what us happening under load. 

 

I cant recall what ecu you are running, but it should be able to log its own voltage if it is any good.

cheers.

Link G4X so yes you're right, i'll plug the laptop in and have a squiz (not used to a car with logging capabilities 🙃

[Dose Pipe Sutututu]

1 hour ago, mr_rbman said:

cheers.

Link G4X so yes you're right, i'll plug the laptop in and have a squiz (not used to a car with logging capabilities 🙃

Start a log, wind out second gear, stop log.

Then look at voltage vs. RPM and see what it's doing.

(This is my experience, may not apply to others) Voltage might be perfect at idle, but over a certain RPM it will fall flat on its face and do nothing then back to 13V+ towards redline. Hard to catch without proper logging.

[mr_rbman]

So I've priced up the LS alternator @ $500 + postage...

Any other recommendations?

I see Frenchy's has released one but it's getting closer towards $700...