GT6 – Oil, Engine, and High Mileage HP Deterioration Guide

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@eclipsee pointed me out to this thread when I experienced that abrupt power boost loss occurring around 200km after an oil change during the Diablo TT. PP dropped from 580 to 575(-5= 0,886% of original 564PP), BHP from 617 to 594(-23 = 3,645% of original 631BHP) and torque from 77,1 to 74,7kgfm (-2,4 = 3,736% of original 64,2kgfm).
so i should expect in the next 100 km or so a further drop to reach that 5%. Figures above are different from the stock ones because of engine tuning.

A question arises here... are engine power improvements affecting the process? I guess not but has anybody tested?
i.e. will the magic oil change boost be the same on a stock engine and a tuned engine?

@Hastatus Amazing work! Thanks for all this knowledge that PD wont bother giving us in a proper manual.
Do you have figures for torque as well? judging from my figures above seems torque percentages follow power in a similar or equal fashion.

@Griffith500 nice plain programming logic find there! Sure you're not a PD programmer?:D

Anyway thank God, PD hasn't thought of GT engines consuming oil like real ones do...
imagine the mess of having to check and top up oil... between oil changes that is...
Now that would be a calculating nightmare for @Hastatus ...wouldn't it:lol:
 
@yannagas : Only HP is boosted 5% by the oil change. The PP and torque amounts will not change in the equal proportion that HP does because they themselves are not calculated with a direct factor of HP.

As for your numbers they do not quite make sense to me (I suspect a typo or an error in recording them):

You started at 631 HP
You dropped to 594 HP
What does 617 HP and -23 HP mean?
Was the 594 HP the lowest amount: i.e. did you drive over 300 km (with the oil deterioration gauge activated)?

Anyways, the oil change boost is easy to test with upgrades. Just do the test in the forward direction: addition versus subtraction.

Take maximum HP after upgrades have been applied and multiply by 1.05: this should get you the same value as you get after the oil change.

I did all the power upgrades to the Diablo GT2, raising its HP to 1006 HP.

Predicted 5% HP boost: 1006 HP x 1.05 = 1056.3 HP.

When I performed the oil change on the car with the 1006 HP the result was 1057 HP.

So the oil change boost does apply to any equipped power tuning upgrades.

It was a good question, yannagas, 👍 so I will update the original post.

[For those who understand the HP rounding issue: the car was actually at something like 1006.2 to 1006.49 HP but PD didn't show decimal place.]
 
@yannagas : Only HP is boosted 5% by the oil change. The PP and torque amounts will not change in the equal proportion that HP does because they themselves are not calculated with a direct factor of HP.

As for your numbers they do not quite make sense to me (I suspect a typo or an error in recording them):

You started at 631 HP
You dropped to 594 HP
What does 617 HP and -23 HP mean?
Was the 594 HP the lowest amount: i.e. did you drive over 300 km (with the oil deterioration gauge activated)?

Anyways, the oil change boost is easy to test with upgrades. Just do the test in the forward direction: addition versus subtraction.

Take maximum HP after upgrades have been applied and multiply by 1.05: this should get you the same value as you get after the oil change.

I did all the power upgrades to the Diablo GT2, raising its HP to 1006 HP.

Predicted 5% HP boost: 1006 HP x 1.05 = 1056.3 HP.

When I performed the oil change on the car with the 1006 HP the result was 1057 HP.

So the oil change boost does apply to any equipped power tuning upgrades.

It was a good question, yannagas, 👍 so I will update the original post.

[For those who understand the HP rounding issue: the car was actually at something like 1006.2 to 1006.49 HP but PD didn't show decimal place.]

yes I suspected that... now there's another question regarding the power limiter....

but first let me explain the numbers:

stock hp was 631BHP that's what is listed on the dealers info card.I bought a second car and 630BHP is listed in the car settings menu and power graph.

during the TT ,tuned engine hp was 617BHP with the oil change because of the power limiter being used to reach 580pp for the TT, it was at 75,4%.
when I noticed the big power drop, i recorded 594BHP . -23BHP is that drop. that drop represents 3.645% of the stock 631BHP.

but... the power limiter was at 75,4% so I suspect that goes into the equation too...

so 75.4% of 631BHP stock = 475BHP with the limiter.

That means the 23BHP drop is 4.842% of 475BHP which is closer to your 5%
And if we do the same calculations with 630BHP as the true stock power, it gets even closer.
Either that or I haven't done enough kms to let the oil boost drop more to your 5%.

just thinking out loud here, I will check ...
 
ok I checked, power limiter is in as well..

so @Griffith500 's law: CurrentHp = stockBrandNewHp * oilFactor * engineFactor * mileageFactor

becomes:
CurrentHp = stockBrandNewHp * HPoilFactor * HPengineFactor * HPmileageFactor *
HPPowerlimiterFactor * HPEnginestageTuningFactor * HPComputerChipFactor * HPExhaustFactor * HPManifoldFactor * HPCatalyticConverterFactor * HPIntakeTuningFactor * HPTurboKitFactor

(Nitrous Oxide acts temporarily and will not affect Current HP data)

The above formula applies to Torque as well:

CurrentTorque = stockBrandNewTorque * TorqueOilFactor * TorqueEngineFactor * TorqueMileageFactor *
TorquePowerlimiterFactor * TorqueEngineStageTuningFactor * TorqueComputerChipFactor * TorqueExhaustFactor * TorqueManifoldFactor * TorqueCatalyticConverterFactor * TorqueIntakeTuningFactor * TorqueTurboKitFactor

(Nitrous Oxide acts temporarily and will not affect Current Torque data)

Torque factors are probably different than HP factors, that's is certainly true for the power tuning factors as we know,
e.g. a given tuning item will have a different influence on Power than on Torque, sometimes a tuning item has no influence on Torque at all )

but i suspect oil Hp factors being very-very close to oil Torque factors... could they be the same?

I experimented both on a used and new Lamborghini Diablo, and my findings suggest the above, though further testing needs to be done.

so on a stock new car (100% limiter) :
564PP - 630BHP - 64,7kgfm did an oil change and got:
571PP - 661BHP - 68kgfm that's a boost of:
5PP - 31BHP - 3,3kgfm.

that is 4,92063% increase in HP and 5,10045% increase in Torque. (as we all know PD's favorite number is 5...)

did the same experiment with the same stock new car at 50% limiter:
475PP - 314BHP - 56,3kgfm did an oil change and got:
482PP - 330BHP - 59,1kgfm that's a boost of:
7PP - 16BHP - 2,8kgfm.

that is 5,09554% increase in HP and 4,97336% increase in Torque. (that again is practically 5%, however pp gain is 7..)

that's weird . in the first experiment there is a PP gain of 0,88652%. In the second experiment that gain is 1,47368% ., That's almost double in the second one...The only thing changed is the power limiter. This needs further investigation..

anyway,

did another experiment with a used car that had some power boost left from a previous oil change,
with 100%limiter, all power improvements, full ballast @50 position, no weight reduction:
620PP - 1018BHP - 92kgfm did an oil change and got:
625PP - 1057BHP - 95,5kgfm that's a boost of:
5PP - 39BHP - 3,5kgfm

that's 3,83104% increase in HP and 3,80435% increase in Torque.. (awfully close numbers... however, 5 is still the PP gain)

this also shows that there was a residual 1,2% boost both in HP and Torque left in the engine from a previous oil change. It also shows that both HP and Torque boost aged and dropped together...
Further experimenting is needed to see if engine wear and mileage have the same effect in HP and Torque..
I only wished @Hastatus kept notes on torque as well during his lengthy tests..

You will ask why did I throw in ballast, ballast position and weight reduction in the game in the last test? They don't affect power or torque. They only affect PP. I did that to see how the PP gain behaves. This is another story, and needs more experimentation.

I did more experiments as the ones above and all of them give very very very close numbers for HP and Torque...
now I need to check on different cars, to cement the above findings.
 
@yannagas

I can see how knowing the Torque and PP might be useful, but I suspect that formulae for these would vary too much between cars: especially once you start throwing upgraded parts on the cars.

1) Torque Deteriorations:

You are looking at Torque in an inaccurate manner. This is how to consider Torque:

c546af195e3ac5c3af2d96a25b8b043c.png


The only way that a % change in HP will be equal to the % change in Torque is if the RPMs never change. The only place that PD puts specific RPM values is on the Car Settings Torque and Power graph where RPMs is marked along the bottom. PD rounds the RPM value for the end of the graph to the nearest 100 RPMs: I believe that this RPM value is marking the range of the x (i.e. RPM) axis rather than being the exact RPM value at the Max HP. Since we cannot be certain exactly what PD is doing with RPMs we can never really calculate the Torque values.

You might think that we could use known HP and Torque values to calculate RPMs, but the Max Torque and Max HP given in the car stats and on the graph are not at the same RPM point on the graph: i.e. they are known at different RPMs. If I am correct about the RPM value showing the graph's range rather than the value of the RPMs at the max HP, then we never even know any two of the three variables at any one time [Except at 0 HP, 0 RPMs, and 0 Torque]. PD does know the exact values because it needs all three at one point in time to create the motion vectors and physics of the cars.

You might be able to determine how the Torque deteriorates for a car by recording the gains and losses of the Torque but they will not be equal rates for every car in the game like those for HP, because the RPMs change at different rates between cars.


2) PP Deteriorations:

If my understanding of Motor City Hami is correct (@Motor City Hami https://www.gtplanet.net/forum/threads/motor-city-tunes-gt6-miata-roadsters.291066/#post-9003798 - Go down to the "Adding Parts" section), then PP deterioration will vary from car to car because the calculations of PP are much more complex and varied than one would think. MCH has shown that there are differing PP to HP gain ratios for individual car parts. The ratios for the same parts on different cars also differ. What this means is that different combinations of upgrades to the same type of car being tuned for a specific PP can have differing max HP results. The same car, the same PP, but significantly different HP values (I consider even 1 HP significant). In other words when racing online two players can have the same car at 500 PP, the same weight, ballast, downforce settings but a couple different power parts can result in one car having more HP and an advantage over the other, even though the PP is exactly the same. (Wait for those who do not know this to go wide-eyed ;)).

Putting this knowledge in another way: two cars of the same type can have the exact same HP using different upgraded parts, but they will have different PP (even if they happen to round to the same PP).


Therefore:
I do not think that calculating Torque and PP deteriorations to be very worthwhile as the rates of change will likely differ between cars. While the HP can be calculated accurately for any car, Torque and PP depend on more than just HP.
 
@Hastatus Thanks for taking the time to reply, I'm quite familiar to Torque, and you are using a correct formula there, but even that is an approximation (5252 is rounded up!:)), and my intention was not to get very scientific about this.

I'm also quite familiar with tuning so i know how different tuning parts act, on HP, Torque, and PP, and can imagine that chaos of trying to calculate PP. That was not my intention either.

I just believe PD is using more simple programming logic, and that's maybe why those graphs are horrible... almost unusable...and not correct...
accurate torque and HP graphs can only be provided by Car manufacturers, or by benching the engines and I don't believe PD can have this (real) data for all those cars.


So I believe they are using some(a few) generic engine physics models , and have tables for some data for every car (accurate or not, we don't know) while the rest of it is automatically generated through a number of algorithms.It's not my intention to find or discover how or what they exactly do.

however finding out what happens to torque is something I would find interesting , as I believe it affects a cars performance in GT6 more than it did in GT5, and generally speaking it is something not many players are aware of,
its a sort of a "left behind" item.

Maybe I find the time to check, or maybe take your advice and spend that time on something more useful:tup:


edit: For knowledge purposes only, Please don't think I'm playing wiseguy,
I would like to correct your belief expressed in part 1 of the above post.

The only way that a % change in HP will be equal to the % change in Torque is if the RPMs never change.

Or if rpm's are 5252, in which case Power expressed in HP and Torque expressed in ft-lbf are equal. Or in a video-game maybe..

The only place that PD puts specific RPM values is on the Car Settings Torque and Power graph where RPMs is marked along the bottom.

PD gives out both max power at specific rpm, and max torque at specific rpm in the Dealership Showroom for most cars.This data PD can get easily, and in most cases these values mach real life ones. Although some times max HP and or Torque values are not exactly the same in the car settings page.

Since we cannot be certain exactly what PD is doing with RPMs we can never really calculate the Torque values.

we can. At least with the same sort of accuracy as we can with HP in this game. (although PD's habit of rounding numbers makes things worse for torque figures because they are smaller)

You might think that we could use known HP and Torque values to calculate RPMs, but the Max Torque and Max HP given in the car stats and on the graph are not at the same RPM point on the graph: i.e. they are known at different RPMs. If I am correct about the RPM value showing the graph's range rather than the value of the RPMs at the max HP, then we never even know any two of the three variables at any one time [Except at 0 HP, 0 RPMs, and 0 Torque]. PD does know the exact values because it needs all three at one point in time to create the motion vectors and physics of the cars.

We can calculate Torque at max power rpm's.
We can calculate Power at max Torque rpm's.

You might be able to determine how the Torque deteriorates for a car by recording the gains and losses of the Torque but they will not be equal rates for every car in the game like those for HP, because the RPMs change at different rates between cars.

Same applies to HP. HP is not a constant value either, it changes throughout the rpm range of a given car.

Think of real life... nothing to do with this game...
Does the same % increase in HP , applicable to all the cars in this game from 20HP TO 1000+ HP, due to new oil, sound logic to you? ... I guess not, you seem to know your cookies! Now make that 5%... Its just a game.

And in that context, I, like you did before giving us the wealth of your knowledge with your experiments and findings, wonder...

to put it in another way:

You're "The Power Guy", who has inspired me, "The Torque Guy" to wonder...
And when somebody wonders about something , sometimes, something usefull comes out

Thanks again for your excellent thread, and inspiration!👍👍👍 @Hastatus
 
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Nice number crunching and in depth knowledge here, great work :bowdown:. I test/tune every car in my garage and noticed that when using M/T HP loss was sooner and occurs at a lower mileage (though slight using like cars at same settings) than A/T, which led me here. Powered through it all since Friday morning and unless I'm just not getting the core concept, what I'm understanding is that "You don't like changing your oil?"...I joke just saying.
:gtpflag:
 
@Hastatus and any other forum friend here, check out this thread I experimented and proved that Torque behaves in the exact same way Power does in this game at least oil-wise for now, among other little things somebody might find useful.
So you need to re-think your view of Torque, its an equal player in GT-6!
Power is a good thing, but not the only good thing anymore.

thanks for the inspiration, one more time!
 
Oil changes shouldn't add the magical 5% HP you talked about. It used to be a cool feature I guess, but it should just be done away with. It's far too annoying and pointless, IMO. Same goes for body and engine overhauls.

A better implementation would be to add actual mechanical and body damage, where if you shunt hard enough or downshift too fast and spin the engine up way past it's capabilities, then you would need engine overhauls and body/chassis restorations.

yes what u said in the last bit of your is in the game, because when i drive my drive my ford GT LM spec 2 test car after an oil change and engine rebiuld and run in the high revs i will only get about 300 km be for the oil starts to get damaged and repair my car's engine a gain with a oil change but this time i run in lower revs i get around 1500 km be for i lose any horse power at all, (i do a lot of endurance races so being nice to the car's engine is very important in last bit of the race) i do a lot of testing in that car and this is one things that i came across, as well some car don't get damaged as fast one of these cars would be the Redbull JR.
 
Hmmm, my 787B had cornering problems when its body rigidity begun to detoriate. Well the OP did say their is no problem when the body rigidity begun to detoriate but my 787B did have problems.
I agree.
My Audi R8 Phoenix has now 11.000 km and just had his 4th body overhaul (second motor overhaul).
I can clearly state that each time, the car started suffering and lap times were noticeable slower. The car was really drifting and sliding on the RH tires.
After the maintenance: everything back to normal.
This time I eved shaved 2.4 seconds of my best time (Nürburg 24' - third lap).
Still, the cost is too high imo...
 
...Amazing work! Thanks for all this knowledge that PD wont bother giving us in a proper manual...

To be fair, I'm not knocking this thread and it's very useful, but it does remove all of the spontaneity and realism from the car maintenance aspect of the game so I'm very glad that PD didn't make this information readily available. Real-life engine wear is supposed to be unpredictable and gradual, and there aren't precise figures for it, so knowing the formulae of all of the in-game mechanisms would remove the immersion and believability of those features for most players. You certainly can't knock PD for not disclosing this information.
 
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I agree.
My Audi R8 Phoenix has now 11.000 km and just had his 4th body overhaul (second motor overhaul).
I can clearly state that each time, the car started suffering and lap times were noticeable slower. The car was really drifting and sliding on the RH tires.
After the maintenance: everything back to normal.
This time I eved shaved 2.4 seconds of my best time (Nürburg 24' - third lap).
Still, the cost is too high imo...
I agree. The rigidity restoration costed 500k for the 787B.
 
This is a nice guide. I just had a Diablo that said oil was green still, but I did an oil change anyway since it had 400miles on it. The hp went way up from 1000 to 1056. Not sure why they wouldn't list the oil as yellow at least.
 
What puts mileage on a car? Covering distance, wheel rotation? If I'm facing a wall and I'm open throttle spinning tires, will km/mi accumulate?
 
I think I've discovered something about engine and oil deterioration:

I've got an Enzo that I've almost exclusively used to race online at 550pp and a few times stock, never changed the oil because that would mean having to use more power limiter to bring it down to 550pp. A while ago I reached 5000km on it and to my suprise the oil light didn't turn on, then I got it to 6000km and the oil still was in good condition. Today the oil finally started to deteriorate, this was at about 6900km, very strange right?

Well, to bring it down to 550pp I keep the power limiter at about 70% (click up, click down, depends on the rear ballast I'm using at the moment).

Then we take the 5000km at which the oil should have started to deteriorate and divide it by the 6900km at which it actually did = 72%

Taking into account the times that I drove it stock ,which would make for the 2% difference in the numbers, I think it's safe to say that the power limiter affects the deterioration rate of the oil and the engine proportionally.
 
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I think I've discovered something about engine and oil deterioration:

I've got an Enzo that I've almost exclusively used to race online at 550pp and a few times stock, never changed the oil because that would mean having to use more power limiter to bring it down to 550pp. A while ago I reached 5000km on it and to my suprise the oil light didn't turn on, then I got it to 6000km and the oil still was in good condition. Today the oil finally started to deteriorate, this was at about 6900km, very strange right?

Well, to bring it down to 550pp I keep the power limiter at about 70% (click up, click down, depends on the rear ballast I'm using at the moment).

Then we take the 5000km at which the oil should have started to deteriorate and divide it by the 6900km at which it actually did = 72%

Taking into account the times that I drove it stock ,which would make for the 2% difference in the numbers, I think it's safe to say that the power limiter affects the deterioration rate of the oil and the engine proportionally.
For some reason, when an online lobby has tire-wear/fuel-consumption turned off, the mileage does not count against the oil life. I think this is more likely the cause of your findings. You could be right though; that would be interesting.
 
For some reason, when an online lobby has tire-wear/fuel-consumption turned off, the mileage does not count against the oil life. I think this is more likely the cause of your findings. You could be right though; that would be interesting.

Oh, I didn't know that... it must be just a coincidence in the numbers then :embarrassed:
 
Not sure if this is the right thread, but my search did not lead to a more appropriate one, so...

Lots of guys seem to test and race cars with the "no oil change !" restriction in big capitals.
I really don't get the purpose of that.
Each and every car I buy gets an oil change before I even start tuning or driving it.
It gives you a 5% gain on HP.
Now, if you don't change the oil right from te beginning and start testing a car, you eventually will have to change the oil anyway and then you get a car that has more power than when you started testing it, right ?
So what's the point ? Can anyone clear that out for me please.
 
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