What are the most important mods you can do to a car, and why

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>>17369140
I'd say that it goes more like this

>tires
>suspension
>engine/trans/exhaust mods (go fast)
>brakes*

*brakes are only really need to be upgraded if you can go sufficiently fast to justify the added braking power

>>17369140
Tyres
Suspension
Brakes

>>17369145
>downplaying the importance of brakes
>how to spot someone who doesn't know what they're talking about

>>17369145
>>17369169
To be fair brakes is a general term. For hotlapping, good brake pads that don't shit the bed when warm are more important than tires. Larger brakes only become necessary when you have so much grip that you can brake harder and not lock the wheels up, or are running into issues with heat dissipation from the rotors.
Tire are equally important to brakes for safety, but you can get away with street tires around a track. The best time shaved per dollar is a set of race tires, though. Finally, adjusting the suspension to maximize cornering grip will improve times further, but should be approached with plenty of research done ahead of time. Also you will sacrifice daily driving with a race alignment unless you have adjustable stuff that you can change in 15 minutes of prep time.

>>17369140
>most important
>not fixing rust

>>17369140
>weight reduction
Should be up there with tires

>>17369169
>How to spot a generalization
Most cars are fine and all they need are uprated brake pads.
For the average nigger on /o/, you can lock up all 4 even after a half hour on the TOOOODGE without brake fade, as you don't reach track speeds. Bigger brakes just mean more heat capacity before fading temps.

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>>17369216

>>17369140
Why do people believe that vastly different cars can be generalised to need specific things upgraded, no matter the design rationale behind them? Makes no sense from an engineering standpoint.

For example, I doubt you'll need to do any of those three on a Viper ACR. Or a Mirage for that matter.

>>17369368
This is how I feel about the

>weight reduction
>>17369216
meme

>>17369216
>he doesn't do weight enlargement

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>>17369414
Don't worry mate, got that covered.

>>17369385
Weight reduction isn't a meme though. Any weight reduction is always good (even moreso on rotational or unsprung mass), since it directly correlates to Newton's second law. Basically, with less weight, you need less force to accelerate forwards, backwards or sideways.

However, weight reduction has two glaring problems. First off, a proper manufacturer will already have done most of it. Second, most further weight reduction comes at great cost to comfort, refinement and NVH values.

>>17369418
Agreed.
The most effort I will go to for weight reduction is rims and maybe PS/AC delete.
Having said that, part two of your post is I also agree with.
The NA miata is already fairly light, what with zero to fuck all noise mitigation and thermal insulation so I'm not getting rid of AC (Summer hits 30c here with almost always 90%+ humidity all day and night) and a manual rack is hard as fuck to find.

Thus far I've only added weight by applying dynamat competitors to the firewall and trans tunnel, wrapped the headers and downpipe and added a hardtop. Even still, it's way down on the casually accepted comforts for a normal car.

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>>17369428
>and a manual rack is hard as fuck to find.
Just convert your auto rack into manual, take it apart, clean it out, remove all the o rings and seals that are in the center of the rack that the fluid acts against, JB weld all the holes in it from the pressure lines, weld the assist valve so there's no play in the steering.
That's what I did in my volvo.

>>17369443
Too bad those will have the wrong ratio for a manual rack.

The single best mod you can do to a car is maintenance.

Are your brake lines in good shape? Calipers moving smoothly? Nothing loose down there? Car still goes straight when you brake?

>>17369443
Driven a few that have done the delete properly, i.e haven't just looped the assembly. They're fine but the ratio is still a little harsh, I'd imagine my Direzza ZII's would be moreso at low speeds.
>>17369446
This. Only the optional no PS miats have the manual rack and with the increased interest in them these days, pretty much impossible in NZ.

IIRC the PS rack is like a 4.3 ratio and manual is 3.8 or something.

>>17369446
The auto rack has a lower steering ratio which is actually better for racing and such, less input needed to get the car to do what you want.
There's very little difference between the racks though, you probably wont even notice it.
Tons of people depower their miata racks, it's a very common mod.

>>17369458
You got that backwards, the power racks have a lower ratio, not higher, which is good.

>>17369461
>>17369458
>>17369446
>>17369443
>>17369428
>save maybe 2hp of engine load
>save maybe 30 pounds of weight
>lose power steering
>slightly improve steering feel
Why do people do this?

>>17369368
>Why do people believe that vastly different cars can be generalised to need specific things upgraded, no matter the design rationale behind them? Makes no sense from an engineering standpoint.

>>17369418
>>17369428
>E-except weight reduction! Weight reduction is always good no matter what!

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>>17369467
Power steering is shit, you don't need it.
I care about weight in my car, I've stripped probably 350lbs out of it
Also less clutter in your engine bay which is nice when you're working on it.

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>>17369461
Trust me to get the ratio the wrong way around.

In any case, I've just bled the cunting thing with fully synthetic PS fluid and added a small inline cooler to stop it boiling over.

will probably try the delete next time I need to fix something, replacing the crankshaft was enough tender loving care for a while.

>>17369473
>RATTLE RATTLE RATTLE RATTLE
Jesus do you daily that?

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>>17369469
>No matter what
Those posters clearly stated the opposite is true for the most part.

>>17369480
How can it rattle if there's nothing left to rattle?

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>>17369480
becuz racekar bro

>>17369368
>from an engineering standpoint.
Trying to imply you have any engineering knowledge.

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>>17369473
All this so you can spin out at 10mph instead of 5mph?

>>17369492
Weighs around 2600lbs, less than basically any car being made today.

>>17369499
So it weighs more than a miata that actually has an interior and probably twice the HP?

>>17369510
>twice the HP
Stock engine made around 110hp, this one isn't stock tho, it's got a V8 in it

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>it's another mrcummy embarasses himself episode

>>17369519
I bet it still gets lower laptimes than a stock miata, even with someone that can actually drive behind the wheel

>>17369519
>Put an LS in it
>brain works too slowly to steer correctly
>makes it a fucking rattletrap droning ronery driver car
>presumably has shit tires on it despite at least tripling the power

>>17369510
Yea but only faggots drive Mazdas

It's like having a pie eating contest, and someone wins by sucking the judges dick

>>17369525
Good thing I also have a miata to drive around
>>17369530
The tires were less than a week old when I recorded that video lol
Too much tire makes a car boring.

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>>17369536
>LITERALLY put worse tires on purpose
>AT LEAST TRIPLED THE HP
>too much tire to drive safely makes a car boring
What is wrong with furfags?

>>17369548
It had the stock motor and was not stripped out at that time

>>17369548
Also the 205/45/16s are wider than the stock 185s

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>>17369550
>cannot control a car with power steering and low power
>removes power steering and triples the power
>removes everything that reduces NVH because muh racekar
Please post more pictures of your cave I'm fucking dying here dude

>>17369531
Hey, autists also drive mazdas, and they aren't gay just because they don't like your gross 3d roasties.

>>17369556
How does power steering help you control a car?
Have you ever driven a car with no power steering?
When you're at speed there's no difference.

>>17369536
If you took all the time and money spent on your "muh no fucks given" volvo and put it towards the miata and learning to drive you would be a competitive race driver in a competitive car by now

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>>17369563
How is it a no-fucks given volvo?
I buffed the paint and put nice wheels on it, I care a lot about keeping the car good looking and nice.
Also I didn't put much money at all into it, when you have a welder and can make custom shit you don't have to spend tons of money on aftermarket parts, you just make them yourself.

>>17369559
With your reaction time, you need to be able to wrench the wheel to correct oversteer without having to fight the car.

>>17369567
>mfw houses like that would sell for 1mil+ in sydney

>>17369569
Having power steering or not is irrelevant once you leave a parking lot.

>>17369567
Looks nice

Volvo's used to get cucked in racing here in the 80's because they used to rip the shit out of everything else and they still thrashed everything

So theirs nothing wrong with racing Volvo's

> having only 130hp in an engine you could get 340hp on stock internals
> knowing that if you head on a jap car, Volvo will win

>>17369595
he doesn't race though

waste of a good car desu

>>17369596
Racing is too expensive, rather just build a race car and drive it on the road.

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>>17369140
>>suspension
>>tires
>>brakes
>In that order
But that's wrong, you idiot.

Tires is first and foremost. Then depending on the car it's brakes and suspension.

>>17369140
>driver
>tires
>suspension
>brakes

fixed

>>17369140
Tires
Brakes
Exhaust/airflow
Suspension

>>17369575
at 5mph you sure as hell will feel the effects tho

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>>17369140
The most important mod is driving lessons. Followed by "what's actually wrong with it", i.e., if the brakes overheat brake upgrade, if the car is too high smaller tires and wheels (and NOT lower the suspension), if the car can't corner well check the alignment (camber, toe, castor bushings), if the suspension bottoms out then mod it (usually springs, dampers and bumpstops - anti-roll bars tend to be already stiff), if not enough acceleration then more power, if not using it as regular car then weight reduction, lowering the CG, and adding downforce.

>>17369140
>What are the most important mods

In the Fate of the Furious, you learned at the beginning of the movie what the most important thing was.

>EL 4-2-1 Header + Tune
>Tires
>Suspension

t. Toyobaru owner

>>17369481
>No matter what

That's called having Faith.

Faith is the attitude of "no matter what".

>>17369895
>But that's wrong

Prove it.

>>17369899
>driver

This.

Doesn't matter what car you drive if you can't drive.

>>17369906
>exhaust over suspension
Stancefag detected.

>>17370028
The poor man's turbo?

>>17369995
>driver
>individual attention

Sounds about right.

>>17370028
Gallo 24

>>17369140
Cold air intake
High air flow exhaust
Coilovers that prioritize smoothness over #hellaflush
Lightweight wheels
Summer tires
Carbon fiber panels


These are better than just doing massive work on your engine, and can make any car pleasant to drive

>>17371451
Is this the most VatoZone post on the board.

Brakes, tires, cooling and reliability engine mods, suspension, more power

Cant go fast if you can't stop fast every time
Cant go fast or brake the fastest without good tires
Dont want overheating and other problems when going fast

>>17371555
I'd put tires before brakes, unless you're planning on taking it to the track where reducing brake fade is more important.
Most stock brake setups can lock up the wheels with minimal effort.

>>17371593
Don't you want to avoid lock?

>>17371614
Yeah, but my point is bigger brakes won't result in more stopping power compared to stock. Braking is limited by traction, so better tires on stock brakes will produce a better result than stock tires on bigger brakes.

>>17371632
>so better tires on stock brakes will produce a better result than stock tires on bigger brakes.
Shid, good point. Actually informative post on /o/.

>>17371420
The tires are the first point of contact and control between your car and the road.

If you have stock tires, or a low quality 'performance' branded road tire on your car then usually you'll be able to break traction before you reach the limits of what your car's brakes and suspension can handle.

Logically, if you have better tires, you won't have to slow down as much around corners because of increased grip. This means you maintain a higher overall speed, and you can utilize your brakes and engine power better, too.

It's like optimizing any system: start with strengthening/improving your foundation and eliminating the weakest link first, then reassess what needs to be upgraded next to give the best improvement. In this case, the tires are usually the weakest link.

>>17371894
Then why does /o/ never talk about tires.

btfo

>>17371894
Fair points. I concede.

>>17369140
>cold air intake
>straight pipe
>tyres

>>1736914 0
Engine
All other answers are the wrong answer

>>17373685
because most of /o/ are idiots and the other half of bus-riders.

>>17373685
Because knowing about tyres means having used them before.

>>17371632
>>17371593
When I first got my rx7 it had generic chink rubber. I put up money for good pads and rotors before the tires.
Going fast with shit rubber may not be ideal but its still possible unless youre on a track and they cant handle heat. Doesnt really happen on a backroad, but brake fade is a real concern especially if going downhill.

>>17371894
>Logically, if you have better tires, you won't have to slow down as much around corners because of increased grip
But you will be exiting corners with a higher speed, gaining even more speed between corners, thus carrying even more speed into the next corner.. The brakes take more of a punishment.

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1. Driver improvement (habits, lack of fear).
2. Driver improvement (take meth).
3. Tires.
4. Mechanical limited-slip differential.
5. Gear / Differential ratios.
6. BOOST / tune.
7. Remove catalytic converter.
...
12. Body / frame bracing / anti-roll bars.
...
52. Suspension.
...
307. Brakes.

>>17373685
How new are you? Tire threads pop up all the time.

>>17374031
About as new as if you don't reply to this your mother will die in her sleep.

>>17374001
>differential
>gearing

This man has a point, no one else has mentioned it yet.

>>17373993
>The brakes take more of a punishment.
Exactly - the brakes become the next step in your upgrade process, because the tires allowed you to reach the limits of your braking capability.

You're still going faster overall because of the improved grip from the tires.

However, if you chose to do the brakes first and left the tires stock, then you would still be limited by the lack of grip and never be able to fully utilize your upgraded braking capability.


Keep in mind that this is just a very, very general way of looking at the problem. You might have a car that already has decent tires, but the brakes are shit enough that mean upgrading them would be better for performance. The opposite case is more common, though - manufacturers have followed a trend of consistently putting bigger and better brakes on newer cars to improve safety, while preferring economical, hard-compound tires that are 'good enough' for the majority of road users, but provide better mileage and don't wear out too quickly.

I'm not saying you have to throw $1,000 semi-slicks on your old MX-5, but the best thing to do in any scenario - building a gaming computer, designing an assembly line, whatever - is eliminate the biggest bottleneck. Most of the time, it's the tires.

>>17374216
Also, as a side note:

Brakes are still very important. Even though I consider tires to generally be the best SINGLE upgrade, it would be silly not to at least throw on a decent set of track-ready pads and run DOT 5 or other high temperature brake fluids in your track car at the same time as you do the tires. It doesn't cost very much and can help eliminate brake fade, which is the last thing you want to have on a track car.

>>17369573
and you're a moron for buying in sydney.

an absolute delusional faggot. move somewhere else. don't pussy out.

>>17369193
>owning a car from before 1990

> POWER
> POWER
> POWER

>>17374037

>>17374583
90s cars a best

>>17369216
Best way to do weight reduction is to go to /fit/

>>17376530
Fucking lmao, driver mods

>>17369995
>if the car is too high smaller tires and wheels (and NOT lower the suspension),
This will change the drive ratio slightly, and you may need to change your gears to compensate.

Lowering your car an inch or two is fine, as long as you do it right. Dont just cut the springs.

>>17374001
>suspension way after roll cage
nigga what.
Coilovers are way less expensive than a roll cage.

>you literally can't increase power until you upgrade everything else first meme

You don't need brembos, adjustable coilovers, and cup tires to handle bolt-ons or a moderate tune. Better pads and rotors are usually enough for brakes, and lighter wheels is a good suspension upgrade.

>>17369140
engine
suspension
tires
brakes

I only put it this way because changing the power output of your engine can affect its size and weight

tires are a wear item and subject to availability
brakes are for going slow unless you have good acceleration

>>17369216
distribution is more important
esp if your FF or RR

>>17376554
I said "anti-roll bars" not "roll cage."

The right mix of anti-roll bars turned my mx-5 into an oversteer toy without any other suspension mods (well, I replaced the shocks with OE-spec 8 years ago). I have seen them entirely change the driving characteristics of several cars.

>>17376710
Wouldn't that fall under suspension mods?

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>>17369995
cool thing about long travel suspension is that it can drop down into a dip
and stop the car body from doing so

suspension top tip
>make centre of gravity lower than roll centre for hectic bants
>don't adjust tie rod length - make car self steering

For a street car, the obvious answer is engine. No one cares that your civic rides like a wooden board and can take every corner at wide open throttle.

For racecars, tires and reliability mods.

>anyone saying engine or power before anything else
>this is what /o/ has come to


Sure is busrider in here.

>>17369216
Not always important for what your goals are. Tires are far and away the most valuable piece of performance for any Motorsport application

>>17369418
Weight reduction is not as important as weight distribution and center of gravity. Excessive weight reduction will also affect suspension geometry and too much will put you worse than when you started

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>>17369461
mrcummy is right. plus he's a great driver. we should all listen to him.

>>17369467
>>save maybe 2hp of engine load
>>save maybe 30 pounds of weight
>>slightly improve steering feel
There ya go

>>17377824
T H I S

>>17376585
know how I can tell you're an all show and no go benchracer?
when you actually learn to drive and start driving fast you'll notice you can carry a lot of speed with even a 100hp shitbox. in this scenario you will come to realize that what prevents you from going faster/carrying more speed is tyres, brakes, suspension and fluids.
once you start going fast you'll notice how easily everything heats up to hell and back and you'll understand why you need parts that are built to withstand high temperatures for prolonged periods.
after you get this shit sorted ONLY THEN you can think about working on the power and modding the engine and all that shit.

I guarantee you that you are not as good as you think you are, and one more thing:
if you're not fast in a 100hp car, you are not going to be fast in a 500hp one.
learn to drive fast and be fast consistently.

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>>17369140
All these faggots here are wrong.

You need a spoiler. It works even better on a FWD car. 9 out of 10 high school girls agree with me. All of these /o/ professional mechanics are wrong.

>>17369169
>think that brake upgrades are worth it in most situations
>how to demonstrate that you're a fucking benchracer
Protip; you can take your awful shitbox which never sees a track, double the power output, put good tires and suspension on it, and you will probably never need to upgrade the brakes unless they were undersized or just shit (drums) to begin with. Brake upgrades are pointless in most cases, if all you're going to do is commute and do an autocross once in a while, you do not need to upgrade your brakes.

>>17378136
>Brake upgrades are pointless in most cases, if all you're going to do is commute and do an autocross once in a while, you do not need to upgrade your brakes.

I actually agree with this.

Also, a common car mag trope is to talk about how "with all that added power this rod's gonna need some serious brakes to keep it under control...." But you aren't going any faster, you're just accelerating more quickly.

>>17378159
Retard benchracers think brake upgrades help you stop faster because they don't know shit about cars. They don't seem to understand that if your brakes can lock up your tires, bigger brakes will do absolutely nothing to help you stop faster. Bigger brakes are ONLY useful for improving heat rejection, and unless you track and are actuall quick or do muh downhill toojey it is extremely unlikely you'll ever overheat your stock brakes.

>>17378136
>>17378159
>>17378171
Shut the fuck up, we're obviously not talking about daily use.

>>17378902
Wrong. You never mentioned track cars you idiot.

>>17376543
Smaller diameter tires means that in one go you:

>lower the car
>lower roll center
>shorter gearing
>smaller castor trail - lighter steering

Maybe this is what plus sizing should be about, rather than making the rim bigger and keeping the same wheel diameter.

>>17380779
True, making your tires smaller does have its benefits.

However, it also looks kinda weird, and can reduce the contact patch a little.

>>17369628
I like your car, look at all of these autists rage at other people doing what they like, lol.

>>17369467
>lose power steering

You don't need it in any car under 2500lbs

>>17369452
Agreed.

>>17369140
Why do people install short shifters when they obviously haven't memorized the fucking shift pattern then spend all eternity trying to find gears?
Why do people install short shifters in general? Literally the only one I've felt comfortable with was in a '13 STi, mainly because it was an easy flick of the wrist as opposed to a flick and a jolt as you had to reach to find the next gear

>>17369446
>>17369458
Buy a fucking steering quickener and install it backwards so it's a steering slowener.

Your ratio will, in most cases, probably end up making the steering even lighter and slower than the OEM manual rack.

>>17380021
I'm not talking strictly track cars, either. If you drive your car heavy regularly, you're going to feel these things regardless.

>>17369221
It's not about braking power, it's about brakes that still work after half a lap.

>>17369140
>suspension
>transmission
>rear end
>tires
>transmission
>transmission
>transmission
>engine
>fuel
>efi

>>17382530
What, who doesn't have the shift pattern memorized? Is this an American thing?

>>17384404

"No"

It is highly unlikely you'll ever overheat your brakes on the street even with added power, unless your car is a piece of shit with marginal brakes from the factory like some old '70s boat. Regardless, you should not be driving fast enough on the twisties or whatever to overheat your stock brakes at any point, that's idiotic. Twisties are almost always full of blind corners and surface contaminants, if you're pushing the car you're just asking to wind up plowing into oncoming traffic at worst and going off the road at best.

in order:
>sound system
>underglow LED
>white gauge inserts
>extra gauges

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>>17386844
This man understands.

>>17386844
Don't forget getting spanked by some old chaps in a yellow sprite:

https://www.youtube.com/watch?v=4-DGMrLGnLg

>>17387455
>shows an R34 doing sick skids
>enters a Peugeot 306 instead

>>17369140
actually depends on the car. if the car is having body roll but not breaking grip, do sway bars first. Otherwise, tires first. I usually recommend upgrading the wheels along with the tires, to reduce unsprung weight and also go lower profile to fit bigger brakes later. as for brakes, the cheapest upgrades you can do is switch to DOT4, braided lines, and better pads.

>>17387540
what is this DOT4 you speak of senpai

>>17387455
why the young group is paki only? Are there no young whites in britain anymore?

>>17387574
2007

>>17369140
>Let me just adjust my backbox mounts a couple of turns and then we can go for a drive
I didn't think Ferrari was this autistic

>>17387554
DOT4 brake fluid. higher boiling point so it doesn't expand as much as DOT3, which most cars run. DOT4 does require more frequent flushes, as it eventually attracts water and kills the performance.
not all brake fluids are created equally though, the DOT3 and DOT4 minimum boiling point ratings are just that, minimum. you can find some DOT3 solutions with boiling point over crappy DOT4 ones, and DOT3 will last longer. But in general, DOT4 is the way to go to in general though.

>>17387554
"racing" fluid.

But even cleaning brakes, changing lines to braided and investing in better pads would probably dramatically improve braking, especially when they get hot.

DOT4 will make brakes really sharp and with braided lines they will have almost no fade, but you will need to flush it frequently or it will separate water, and start being shit while fucking up entire system with gunk

>>17387721
>>17387620
dudes dot4 doesnt absorb water any faster than dot3 you flush it as frequently as dot3 stop being alarmist

First thing I put on my 2017 WRX is catch cans.

>>17387752
if you actually do flushes when you should. the problem is people forget about their brake fluid and let them go forever.

>>17387752
more precise explanation:

>Another point to make here is there are two boiling temperatures for brake fluid, Dry and Wet.

>When you've just replaced your brake fluid and the system has been properly bled, you are working at the Dry boiling temperature. Over time, water works its way into the system through age, heat cycling, through the hoses, etc. You are then working at your Wet boiling point for the fluid.

>So again, if you get stuck in a spot where you need to put some new brake fluid into the system and all you have available is DOT3, most likely at that point your DOT4 has degraded some and the fresh DOT3 will be close to where the DOT4 is at, but this won't stay true, the DOT3 will degrade once in the lines so the above statement of replace it as soon as possible holds true.

If you want even higher temperature retention you can try DOT 5.1.

Just be careful to NOT use DOT 5.0.
5.0 is pretty great, it has the same boiling point as 5.1 (260 °C or 500 °F dry), but is silicone based and will fuck up your ABS, literally might kill you