GT5 Quick Tune: ***VERSION 3.1***

Hi guys,

I got a newbie-question. I played around a bit with the transmission calculator. I want to (and have already) tune a BMW M3 GTR, not the race one. It has a pretty steep and narrow powerband. The rev-limiter kicks in at 8900 rpm, but the hp only rise till 7400 rpm and after that decrease fast. I tried it several times and it seems that it won't drive faster than 270 kmh on the long straight on the Nürburgring.
If I put the figures in with 270 kmh max speed, it doesn't ever get there, because, as I mentioned before, after 7400 rpm there's nothing coming anymore. I simply raised the top speed in the menu to around 310 and now it works quite fine I think. I just wanted to know if this was the right way to do it.

Another question: do I have to shift precisely at 7400 rpm or a bit later? It seems to me, that the car pulls better if I do at 7400 rpm. Please help, I want to create a race-machine :)!!
 
Yeah, cars that run out of power way before redline are a pain in the neck. You definately want to raise the final in order to end up with a decent top speed, but there's really no hard and fast rule on exactly how much to raise it. If I had to guess, I'd say you'd probably want the car to top out on SSR7 with the engine running halfway between peak power and redline. In this case, halfway between 7400 and 8900 rpm would be 8150, so that may be a good place to start. Shift points are also another difficult issue. In order to properly calulate them you'd need a dyno style printout of engine torque readings in something like 100 rpm increments, then multiply them by each individual gear ratio, then plot everything and see where where each gear overlaps the next. Obviously, not going to happen. One thing I do know is that the optimum shift point will not be the same in each gear. Since the gears get closer together as you keep upshifting, your shift point needs to go lower. For example, you might want to try something like this:

1st: 8600 rpm
2nd: 8200 rpm
3rd: 8000 rpm
4th: 7900 rpm
5th: 7800 rpm

You definately don't want to shift at peak power. Upshifting causes a huge drop in multiplied torque being transferred to the wheels, so you want to wait until to engine output really starts to plummet before you can justify short shifting.
 
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Oh I see, there's much more to it than I expected. All seemed so easy :). I'm afraid I definately will have to put more time and effort in learning some basics on cars before I can start to tune 'em properly in GT5. Thanks for your detailed answer. I'll stick with Assassin's tune for now.
 
Any info on if/when we can expect a new version? I've been using 3.1 and 3.2 with relatively good results, but any improvement is always appreciated. By the way I highly prefer the braking calculations in 3.2 though being able to adjust both bias and strength would be perfect (though I understand that this is probably not possible or extremely difficult).:)
 
InitialD91
Any info on if/when we can expect a new version? I've been using 3.1 and 3.2 with relatively good results, but any improvement is always appreciated. By the way I highly prefer the braking calculations in 3.2 though being able to adjust both bias and strength would be perfect (though I understand that this is probably not possible or extremely difficult).:)
Click to expand...

I haven't fully developed enough ideas to justify a new version quite yet. I'm tossing around the idea of creating special settings for rally cars and the X1 and F1 cars, but it will be a bit tricky and they won't work in conjunction with the balance fine tune function. I would still like to add help flyouts as previously suggested, but other than that I have no major revisions planned. Good to know that you like the new brake bias system, hopefully I can get some more feedback before deciding whether or not to fully implement it.

Firecracker
Many thanks to both you, oppositelock27 and RABIDMAGGOTT, for you're hard work!!
Happy Holidays
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:)
 
Brake Bias is a very useful and technical aspect of race car tuning, especially for Rally races. I think it would be welcome addition if fully implemented!!
SKOAL
 
Dear good sirs: I do not envy you the time it must have taken to make this amazing catalog, but I surely applaud it! Thank you so much!
 
Aquila76
Dear good sirs: I do not envy you the time it must have taken to make this amazing catalog, but I surely applaud it! Thank you so much!
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You're welcome. It's been a multiple year process (the gear calculator was originally created for GT4) but seeing people making good use of it makes it all worthwhile. So far I'm over 6000 combined downloads. :cheers:
 
oppositelock

If you haven't done so already, could you elaborate more on the Advanced User Options section in your gearing spreadsheet? I'm having trouble understanding what these values affect.

Fixed F/R/AWD spread +/- 5%
Power/Weight spread range 20%
Powerband spread range 20%
Manual spread adjustment 100%
Manual gear set multiplication 100%
 
carguy7a
oppositelock

If you haven't done so already, could you elaborate more on the Advanced User Options section in your gearing spreadsheet? I'm having trouble understanding what these values affect.
Click to expand...

No problem.
Fixed F/R/AWD spread +/- 5%
Power/Weight spread range 20%
Powerband spread range 20%
Click to expand...

These three are for really advanced users, and frankly I think you're better off leaving them alone. Basically they adjust how much weight each of these parameters have over the gear ratio formulas. The bigger the percentage, the more influence it carries. I included these mostly for my own personal use and I think the defaults are pretty darn good.
Manual spread adjustment 100%
Manual gear set multiplication 100%
Click to expand...

These two are really important, however, and are identical to the Spread and Scale features in Quick Tune, respectively. Refer to the first post for a detailed description on how to use these. You will likely use Spread quite often, either to fit the ratios into the allowable range or as a sort of advanced "tranny trick" for things like drag racing. The gear set multiplication aka Scale feature should only be used when the ratios don't fit as there is no performance to be gained otherwise.
 
I'm interested in this, but downloaded it (in a safe place) and immediately got a Windows Security Center trojan.

Mind cleaning it and uploading it again, or, better yet, putting it in Google docs?
 
Vol Jbolaz
I'm interested in this, but downloaded it (in a safe place) and immediately got a Windows Security Center trojan.

Mind cleaning it and uploading it again, or, better yet, putting it in Google docs?
Click to expand...

Over 1200 downloads of 3.1 and you're the first person to mention this. I scanned my copy with AVG and got nothing. I think you got it somewhere else. None the less, I will PM you a link to a Google Docs copy.
 
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oppositelock
I included these mostly for my own personal use and I think the defaults are pretty darn good.
Click to expand...

I completely agree. Just by using the spread sheet at default settings, I was able to knock off at least 1.5 seconds/lap on various cars and the cars power range was really noticeable. Acceleration is much smoother and much more predictable in each gear. I just didn't know if it was necessary to change these. Now I know. Thanks.
 
oppositelock
Over 1200 downloads of 3.1 and you're the first person to mention this. I scanned my copy with AVG and got nothing. I think you got it somewhere else. None the less, I will PM you a link to a Google Docs copy.
Click to expand...

That is entirely possible. I downloaded it to a machine that I download stuff to, a quarantine. It is possible that the virus was on a previous download went undetected, and was waiting to see another download. It was a trojan that pretends to be Windows Security Center alerting you to a virus to phish information when you go to upgrade your AV software.

Thanks for the Google link. I personally don't see the need in MS Office anymore. I think Google docs and places like it are the future.
 
carguy7a
I completely agree. Just by using the spread sheet at default settings, I was able to knock off at least 1.5 seconds/lap on various cars and the cars power range was really noticeable. Acceleration is much smoother and much more predictable in each gear. I just didn't know if it was necessary to change these. Now I know. Thanks.
Click to expand...

That's an interesting observation, and one that I'm having a hard time explaining. Any chance of going into slightly more detail?
 
-While we're on the topic of the gearing calculator: any chance that you can explain the formulas that you used to determine the gearing? I have been trying to figure out how to improve my results and I though I'd give the formulas a look and could not figure them out. I'm not asking for a full-on explanation, but a brief overview of how you came up with them would be greatly appreciated.
-Also, and news on a new version of the suspension calculator? It works extremely well as-is, but I will never complain about improvements.
 
InitialD91
While we're on the topic of the gearing calculator: any chance that you can explain the formulas that you used to determine the gearing? I have been trying to figure out how to improve my results and I though I'd give the formulas a look and could not figure them out. I'm not asking for a full-on explanation, but a brief overview of how you came up with them would be greatly appreciated.
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That's a bit of a challenge but I'll try. Anyway, first off I decided I needed one fixed ratio as a sort of fulcrum to pivot the other ratios around. Since many older transmissions have a 1:1 second-to-last gear with top gear being overdrive, that seemed like as good a reference point as any. The very first formulas I came up with had each gear as a fixed percentage of the adjacent ones. For example:

1st: 1.953 x 125% = 2.441 ˄
2nd: 1.563 x 125% = 1.953 ˄
3rd: 1.250 x 125% = 1.563 ˄
4th: 1.000 x 125% = 1.250 ˄
5th: 1.000 (Pivot) = 1.000
6th: 1.000 / 125% = 0.800 ˅

This should have resulted in the engine dropping to the exact same RPM upon each upshift. Suprisingly, it doesn't work that way and the RPM drop actually increases significantly as you run up though the gears. Also, the resulting ratios almost never fit in the allowable range as the lower gears are far too tall. No good.

The second set of formulas I came up with involved averaging a unique set of fractions for each gear. This involved months of trial-and-error, so I'm not going to summarize the process, but here's an example:

1st: AVERAGE(5/1,6/2,7/3) = 3.444
2nd: AVERAGE(5/2,6/3,7/4) = 2.083
3rd: AVERAGE(5/3,6/4,7/5) = 1.522
4th: AVERAGE(5/4,6/5,7/6) = 1.206
5th: AVERAGE(5/5,6/6,7/7) = 1.000
6th: AVERAGE(5/6,6/7,7/8) = 0.855

This was far better than my previous formulas but something was still not right. The lower gears were too far apart and the higher gears were too close together, which was the opposite problem of my first fixed formulas. That's when I hit on the idea of averaging these ratios with a set of fixed percentage ratios, and the results were PERFECT. I'll avoid posting the final formulas in their entirety, but this you should help you read the spreadsheet.

Ok, so now I had a set of baseline ratios, but how to adapt them to a particular car? I eventually determined that the three most important vehicle parameters were:

Drivetrain: AWD has more off-the-line traction than RWD, which in turn has more traction than FWD. The more traction, the shorter 1st gear you can get away with, and therefore a wider spread overall

Powerband: Low torque, high revving engines will require closer ratios than high torque, low revving engines.

Power-to-weight ratio: Faster cars will be more traction limited than slower ones, therefore requiring a taller 1st and a tighter spread overall.

These three parameters are then averaged, and the baseline ratios are modified accordingly.

Also, and news on a new version of the suspension calculator? It works extremely well as-is, but I will never complain about improvements.
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Right now I'm fairly happy with it and don't foresee any major revisions. As stated previously, I'd eventually like to have special settings for rally cars as well as F1 and X2010/11 cars, which would be represented as suspension levels 0 and 5 respectively. I wouldn't expect any changes for levels 1 though 4 unless PD decides to give us more tuning tools to work with.
 
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oppositelock
That's an interesting observation, and one that I'm having a hard time explaining. Any chance of going into slightly more detail?
Click to expand...

It is hard to explain but I'll try.

Well to me it seems each individual gear is not as short as default settings. I really notice the difference between 2nd and 3rd. With default settings, when I get into a turn that required to downshift to 2nd, it seemed that 2nd gear was too short and 3rd would be too tall IE (2nd gear too many rpms 3rd not enough resulting in slower speeds through that corner). After using the spread sheet 2nd gear is just right and I can carry more speed through the corner. Some of the higher powered cars in the 800+hp range have too much wheel spin in the first 3 gears at default gear settings, after using your method, it helps eliminate some of that wheel spin while improving on the car's power range.

All I know is it cut about a 1.5 second average off my laps and the car felt like it pulled consistently throughout the gears.
 
Yeah. I was looking in the thread that had all of the tuning guides and what not. And I saw yours and I was like I'll give it a try when I get back to my dads house. I figured it out rightaway. Your program fixed many problems on my cars that I could not fix to save my life.
Note: I think you should add a rally section or make a program for it. That would help loads of people. But these are just suggestions.
 
MiDriftSmoke
Note: I think you should add a rally section or make a program for it. That would help loads of people. But these are just suggestions.
Click to expand...

I agree, I have something in mind for rally, I'm just trying to figure out how to implement it. I also do very little rally racing/tuning so I need to do quite a bit of additional testing in order to figure out what really works and what doesn't.
 
Cool. Yeah, a rally section would be good for people who like rally ,but don't really know how to tune for it, like myself. I am a very bad rally tuner. That's why I suggested it.
 
Yea. Its just that I have to take an extra step to open the pre-made tune. I don't know if you could make another file for people that use the diff software.
 
I'm not sure what extra step you mean. They're all the same file type and, to the best of my knowledge, should open in all three programs mentioned.
 

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