Survey: single most effective modification to a car

Scaff
BT, if you follow the 'car won't stop quick enough' link in my sig you will find that a number of us have started this with regard to stoping distances, focusing on tyre choice, weight reduction and sports brakes.

You may be interested in the results, as it explains why I woulld go for tyres before weight reduction.

Could not agree with you more on the FF and LSD point, it makes a huge difference to FF cars, it transformed my tuned Integra Type R (DC2).
Click to expand...

I agree 100% with your point of view ( you did your homework, good thread ), that's why I mentioned tires and not brakes in my mods list.
My objection is that " racing is not just braking" :) that's why I want to make some tests.
I'll start with a typical FF car , the Civic looks like a good candidate .
What about the track ? It shouldn't be too small nor too big with a variety of curves and maybe some uphill. I'm thinking about Autumn ring.
if some of you are interested, they could experiment with some medium powered FR and MR cars.
Why waste time trying to gold the license tests when we can use it for some GT4 experiments that will be useful to the whole GT4 community.
 
Biased turkey
I agree 100% with your point of view ( you did your homework, good thread ), that's why I mentioned tires and not brakes in my mods list.
My objection is that " racing is not just braking" :) that's why I want to make some tests.
I'll start with a typical FF car , the Civic looks like a good candidate .
What about the track ? It shouldn't be too small nor too big with a variety of curves and maybe some uphill. I'm thinking about Autumn ring.
if some of you are interested, they could experiment with some medium powered FR and MR cars.
Why waste time trying to gold the license tests when we can use it for some GT4 experiments that will be useful to the whole GT4 community.
Click to expand...

You can count on my support for anthing of this nature, and I know a few others whom ay be interested.
 
Scaff
You can count on my support for anthing of this nature, and I know a few others whom ay be interested.
Click to expand...
Thanks for the help Scaff.
Now we should establish the testing procedure so we get ( I hate that word ) ...unbiased results that anyone can check or try to reproduce for comparing.
Track ? which one ? I suggest autumn-ring or is it too complicate ?
Tsukuba with a fast open curve , a hairpin and a long straight looks good too because it's a simple track

mods: I would start with basic mods, such as sport muffler, sport suspension, weight reduction stage 1 etc..

Results: I was thinking of what gives the best bang for the buck ?
for a specific mod, divide the PERCENTAGE the lapping time is decreased by the amount of money it costs to buy the mod.
Because obviously, NA tuning stage 1 will get you faster than a sport flywheel, but it costs more $ too.
Suggestions from anyone are welcome.
 
skicrush
OK, my vote is Laguna Seca for the test run. And I'm thinking a 350Z or RX-8--FR, mid range power, weight, and decent handling. Fairly average in all respects--will give us a good idea of what single upgrade gives the best results. I can't do this until I get a little time, but this is what I think needs to be done. Some other cars might be better, but I can't think of anything off the top of my head. Reset it back to stock after every trial. Here's the lineup.

1. Stock, stock. Tires that come with it (sport med, prolly). Yes, has an oil change.
2. Tires. Racing med? No softies--we're trying to be practical.
3. Suspension. Sport or Race, but leave it how it comes. Too many avariables if you tweak it.
4. Racing chip.
5. Flywheel/ triple clutch/carbon driveshaft.
6. Stage 1 Turbo.
7.Stage 1 NA.
8. Stage 1 WR.
9. Stage 2 WR.

Now, never having unequipped a weight reduction or NA tune, I'm not sure if you can UNequip them. That's why they're last. I combined #5 (drivetrain components) and added stage 2 weight (because stage 1 is so cheap)--just trying to get some cost parity (yes, with those expensive tires). I won't have time to get to this for 2 weeks (since I think it all needs to be done at the same time), but if anyone else wants to try it, I'm sure there are a couple of people interested in seeing the results.
Click to expand...

Yeah, I'm quoting myself. You got a problem with that? Now that we have soem people on board the testing wagon, what do you guys think about this setup? It would obviously be different for every car, but several of us could pick cars and try it out. Unfortunately, I'm still a week away from having any time to do this. Anyone in?
 
I like the idea; it's a little something like what I did in GT3 with a 1997 Camaro....Performance through the quarter mile, a test of the '97 Camaro

My test is a bad one, considering you guys are using an actual track, but I thought I might put this up for an idea....:dopey: Of course, the best performance increase came from the NA Stage 3 addition, and it didn't help that my test was a cumulative one, instead of an individual parts test. It would also be a good idea to test individual tires and their effects. (Like the difference between N1's and N2's) Just some thoughts....
 
I say depends on the car. Tires seem to be the general census on a car. But if you put racing tires on a Daihatsu you've just wasted a crap load of money (in real life).

If it's a top end car, yeah sure tires.
If it's a low end car, could be engine swap, could be turbocharging, could be a # of things.
 
exhorst
i think the fully customisable transmission because you can squeeze the maximum performance outta ya car with acceleration or top speed

stage 1 weight reduction aswell
Click to expand...


Agreed. 👍 Highly overlooked as detrimental to the cars performance. Even before tires and brakes you can get better results.

My list kinda goes:

1. Brakes
2. Tires
3. Tranny
4. Engine
etc


I really dont value NOS right off the bat because its really meant to be a boost on top of what you have, not just a cheater cushion to make up for slamming into a wall. :yuck:

Its very counter-productive IMO to do even the slightest thing to the suspension until you figure out how fast its gunna go and what kinda behavior you have in turns at that speed/breaking.
 
Driftster
I say depends on the car. Tires seem to be the general census on a car. But if you put racing tires on a Daihatsu you've just wasted a crap load of money (in real life).

If it's a top end car, yeah sure tires.
If it's a low end car, could be engine swap, could be turbocharging, could be a # of things.
Click to expand...


Try racing the Daihatsu 1-make races (midget and copen) stock vs. w/ racing tires and get back to me. 👍

-a
 
Driftster
I say depends on the car. Tires seem to be the general census on a car. But if you put racing tires on a Daihatsu you've just wasted a crap load of money (in real life).
Click to expand...

The first autocross I ever competed in, I was in my stock 271 HP Evo 8.

I drove pretty well -- took 3rd out of 9 in my class, but I got beat by a trio of H Stock 115 HP Mini Coopers. The difference -- tires.

In real life, as in GT4, racing tires on an underpowered car allow you to drive much deeper into the corner, to corner faster, and to get back on the throttle much sooner.
 
For sure...
Pretty nice Professional Suspension setup!

For example: I made 1m05s in Midfield sometime, original settings!
When I bought [?!] professional suspensions, it turned into 1 minute flat! ^^

With SSR Tires, my time was 1m01s
With brakes, it was 1m03s

BUT...

When i bought Stage3 Turbo, it turned into 56s
 
skicrush
Yeah, I'm quoting myself. You got a problem with that? Now that we have soem people on board the testing wagon, what do you guys think about this setup? It would obviously be different for every car, but several of us could pick cars and try it out. Unfortunately, I'm still a week away from having any time to do this. Anyone in?
Click to expand...

Laguna Seca sounds good too, so I'll test the Civic "R" ( new model, not an used one ) both at Tsukuba and Laguna Seca.
The only feature Laguna Seca is missing is a long very open curve ( like the last curve at Tsukuba )
Did some free run with the Civic at Tsukuba yesterday evening and it brought a question: What about driving assistance ( oversteer, understeer and TCs ) should they be set to a default value or set to zero ? ( imho they should be set to 0 , unless someone has a better suggestion )
How many laps for each test ? 10 ?
Should we take the best lap as the result or the average of the 3 best laps ?
I didn't try B spec yet but if we can run time trials in Bspec mode it would assure a consistency with the results.
 
OK, I think I"ll have enough time to do this tonight. Glad to have someone testing an FF--I'm pretty useless driving FF. I don't know if I'll b-spec it or not. I'll probably play with it and see what works best. I haven't used b-spec yet, and if my driver is too stoopid, I'll sack him and do it myself. I think 10 laps might be a little much! how many did I have to test? 9? I think 5 should be plenty. That's 45 laps total. 90 seems excessive. 1-2 laps to warm up the tires and get used to whichever change you made, and 3 more to go hard and see what you can wring out of them. I'd also recommend re-testing stock about halfway through and using that improved time (anyone should be turning better times after 20-25 laps). That will also give us a feel for how much our initial few tests may have gotten better because we got better. I guess the more I think about it, the better idea B-spec looks, if its available.
 
In GT4, Racing brakes do ABSOLUTELY NOTHING. They are psychological aids. See our testing in the "GT4 and Braking" thread: (it's a very long thread, these two posts get you started, but really, if you doubt, keep reading because we tested EVERYTHING).


https://www.gtplanet.net/forum/showpost.php?p=1561132&postcount=218

and

https://www.gtplanet.net/forum/showpost.php?p=1559031&postcount=193

and

https://www.gtplanet.net/forum/showthread.php?t=58993&page=12&pp=20


Personally (and I haven't tested this yet), I'd say the best improvement per credit is horsepower (just find the cheapest hp/credit upgrade, usually the chip) and buy it. Next up is tires. Then suspension/transmission depending on the course).
 
I'm in for testing.

I suggest that if you do test, you do "Blind testing". You should NOT know what "Improvement" was made to the car. If you do, then you may subconsciously try harder or less hard to improve your time. You should have someone else set your car settings for you. Then do you trial runs. Afterwards, you can record your time and impressions, THEN look to see what the mod's were.

Tires should definitely be one of the variables.

Suspension (and suspension settings) should be considered.

I second the RX-7 or similar mid-size mid-powered car.

Track should have at least one long straight, but probably not more. A good balanced track like Apricot Hill might be fair. Or, post times from two different tracks. One emphasizing power, the other technical handling.

2byxw7
 
Yeah, I like apricot hill. I actually pm'd turkey, suggesting that track as a possble good balance between straights and turns (some sweeper situations, too). I think I'm gonna try a 350Z and probably a DB9, to see what a higher power, higher weight car benefits most from (I already have 2 DB9's, anyway. I might as well use them). Is everyone happy with the final list here? I added tranny as #10, and think that's a pretty inclusive list. That's 55 laps, if you take your stock car for a second spin about halfway through for a control. See you tomorrow with some results!

1. Stock, stock. Tires that come with it (sport med, prolly). Yes, has an oil change.
2. Tires. Racing med. No softies--we're trying to be practical.
3. Suspension. Race, but leave it how it comes. Too many avariables if you tweak it.
4. Racing chip.
5. Flywheel/ triple clutch/carbon driveshaft.
6. Stage 1 Turbo.
7. Stage 1 NA.
8. Stage 1 WR.
9. Stage 2 WR.
10.Race tranny, geared for the track.
 
skicrush
3. Suspension. Race, but leave it how it comes. Too many avariables if you tweak it.
Click to expand...

Those "variables" are what make the race suspension worthwhile.

In real life, it took me three autocross events to tune my suspension -- playing with ride heights, alignments, and damper strengths -- and the car improved a heck of a lot over the "stock" settings of my aftermarket coilover suspension.

At the autocross National championships in Kansas last September, I talked with one competitor who brought six sets of springs to the event...

Leaving the suspension "as is" sort of misses the whole point.
 
OK, I totally agree, but I only have so much time, and I am not going to run 20 laps to tune the suspension on top of the 5 laps for each different mod that I'm already going to run.

If someone (JBRENNEN!!!) wants to give us suspension settings, I'm all for it. I'm testing a 350Z and a DB9, Turkey is testing a Civic "R", and I dont' know what FIDO's going to use. Maybe the RX-7 he suggested. Anyone up for doing an M3?
 
OK, here is the cold hard data. Testing was done on Apricot Hill, on B-spec setting 3. Except there is no way to completely control everything, even with B-spec, because your driver is always getting better. I had to do a lot of retesting to feel comfortable comparing apples to apples, and that's why there's no time for the racing chip (it was late and I didn't redo it--sue me). Also, I need to finish the DB9's set. But it is clear what your best mod is, and what your best mod for the dollar is. So, without further ado, the numbers.
_________________________________________________________________

350Z Description Best Time Cost Differ Sec/1000 cr.
1 Stock Car Time ll 135.158
2 Race Med Tires ll 130.171 ll 22500 ll 4.987 ll 0.221644444
3 Race Suspension ll 135.071 ll 17000 ll 0.087 ll 0.005117647
4 Racing Chip ll 1200
5 Fly/Clutch/Dshaft ll 134.927 ll 8750 ll 0.231 ll 0.0264
6 Supercharger ll 131.349 ll 13500 ll 3.809 ll 0.282148148
7 Stage 1 NA tune ll 134.382 ll 4900 ll 0.776 ll 0.158367347
8 Stage 1 WR ll 134.542 ll 1200 ll 0.616 ll 0.513333333
9 Stage 2 WR ll 134.214 ll 5500 ll 0.944 ll 0.171636364
10 Race Tranny


DB9 Description Best Time Cost Differ Sec/1000 cr.

1 Stock Car Time ll 132.75
2 Race Med Tires ll 127.221 ll 22500 ll 5.529 ll 0.245733333
3 Race Suspension ll ll 16000
4 Racing Chip
5 Fly/Clutch/Dshaft
6 Supercharger NA
7 Stage 1 NA tune ll 132.487 ll 4900 ll 0.263 ll 0.053673469
8 Stage 1 WR ll 131.323 ll 1200 ll 1.427 ll 1.189166667
9 Stage 2 WR ll 130.932 ll 5500 ll 1.818 ll 0.330545455
10 Race Tranny

_________________________________________________________________

I stand corrected. Racing tires (or tyres) spanked everything. I thought WR would be best AND best for the $$$. It was not--just best bang for your buck. The chip might be close to WR 1, but even from the imperfect numbers I got for it, I can tell it won't be close enough to edge out WR 1. I'll have hard numbers for it tomorrow, and even then, it is only high for the 350Z.

There are different conclusions to be drawn about the different cars. And there will be more when Turkey and FIDO finish their testing. The heavy, high powered DB9 benefitted immensely (% wise) from WR1, while power upgrades did almost nothing for it. Tranny might wind up being a sleeper for the DB9, but I doubt it. I may also try upping hp as much as possible for 22,500 Cr, and that should be VERY competetive, but my feeling is that tires will still win out. It looks like I'll need to go home for lunch today!
 
id say the supercharger and racing tyres are the best upgrades, if expensive. tyres make the handling and acceleration better, and supercharger makes the speed better. other than that, triple clutch does no end of help for gear changes. i hate sloppyness
 
I think the 350Z and the RX7 are a little too similar. So, I'll try a Miata (I'm guessing that power will help this underpowered car more, % wise).
 
FIDO69
I think the 350Z and the RX7 are a little too similar. So, I'll try a Miata (I'm guessing that power will help this underpowered car more, % wise).
Click to expand...

Good call. You'll need SOME B-spec points before you will be able to compare differences. My B-spec driver gained 3 seconds after 30 laps, since I'd never used it before. Also, I ALWAYS got the best time on the 2nd or 3rd lap. I stopped running 5 laps per and started going 3-4 to save time, and to keep driver improvement from making such a difference.

I think I'll try out the Z06 tonight to see how a powerful balanced car benefits. I should probably try out a MR, too, but I'm fairly undecided. I tend to think that tires will do even better in a MR setup than in the FR's we have and are trying, and the FF turkey is going to test. But I suppose in the name of science we ought to at least give it a go.
 
Incomplete research...

My b-spec guy (3290pts, 44/36/27) was wildly inconsistent (mostly crashing in turn 2, the hairpin, and the chicane). I'd say at LEAST 10 laps would be necessary to get a reasonable estimate. Even then, I was easily able to beat him myself with just 1 or 2 laps.

Therefore, I'll only report my a-spec times:

Miata, '97, special edition
All times are after stage 2 weight reduction (used my first car bought)
All driver aids off. TCM/ASM 0/0
Best time with a 5lap cap (started with, then repeated stock test after all others. 1-2more seconds per lap are easily possible)

Stock Car......................1'45.429
Race Med Tires...............1'38.884....-6.545
SemiFly/3Clutch/Cshaft....1'44.545....-0.884
Turbocharger1................1'40.464....-4.965
Stage 1 NA tune..............1'41.815....-3.614
Race Tranny...................1'44.992....-0.437
+200 ballast...................1'46.977....+1.548

I won't make any conclusions from these because my lap with the Turbo happened to be the best of the night (really nailed it). I'm quite sure I could do as well with the NA.

The tires are the easiest to drive around fast in. That does not mean that they are actually the fastest. :odd:

I see now that this track is weighted towards the turns. I'd wager that sweepers, chicanes, and s-turns are good for better tires. Hairpins, 90deg turns, and straights are good for HP mods. (But remember, the amount of time that you gain depends on the amount of time you spend in that portion of track. i.e., a 1mph gain on a straight that you spend 10sec in is not as good as a 1mph gain in a sweeper that you spend 15sec in).

FIDO

edit: fyi, tested weight (w/o ballast) = 921kg, showroom stock = 980kg
 
Just to add:

I agree that weight reduction is important in GT4 (for accelerating and possibly for cornering), but it does NOT affect braking. See tests in the "GT4 and Braking" thread.

And while braking is very important for passing and winning races, there are few tracks where you are braking more than you are accelerating. Braking zones at Apricot hill amount to 3 places (hairpin, end of straight, and before the chicane), and you are on the brakes for probably a grand total of 5sec per lap.
 
Best for performance and best value - supercharged (added just short of 100bhp for only $13.500)

Best for handling - weight reduction and tyres.
 

Latest Posts

Back