Braking power: The relationship between tires and brakes

A popular question in the car world is one regarding braking power: How do I get my car to stop faster? Simply put, a moving object – in our case, a car – is stopped by friction. When you lock up your brakes and stop your wheels from rotating, you are transferring the stopping requirement to your tires. It is then up to your tires to create sufficient friction to bring your car to a halt. If your wheels are locked up, there is nothing that a big brake kit can do that isn’t already being done. On that same note, you can have the biggest brakes possible for your car, but if you have low-quality tires, it won’t matter.

Sure, bigger brakes can allow you to stop with less pedal pressure, as they create more friction sooner than the OEM setup. But, speaking purely about a situation where already you have your OEM brakes completely locked up, tires are the only thing remaining to bring your car to a halt.

If your car isn’t stopping well or quickly enough, it’s likely that you need better tires. If you install good tires and now your problem is brake fade, you need better pads. If you install better pads but now parts are overheating, you need bigger brakes or better airflow for cooling & heat dispersion. I’m not saying that big brakes are useless; rather, I’m saying that people often make the incorrect assumption that brakes are the primary (and, to some people, only) thing responsible for stopping your car.

Now that we’re on the same page, I’d like to make three quick points on the relationship between your tires and your brakes.

  1. After you’ve applied the brakes, your tires stop the car. If you’ve installed low-quality or undersized tires (for instance: stretching a small tire onto a wide wheel, which seems to be all the rage with some IS owners…), your brakes are powerless, no matter how big they are. If you’ve engaged the ABS, the only thing that will stop the car is stickier or larger tires. If, for some reason, you can’t engage the ABS, it’s likely that your brakes are worn out or your current pads aren’t up to the task.
  2. Your pad choice affects brake fade. A better pad can sustain higher temperatures longer before it will fade. This is true to a point – if you keep upgrading pads, you’ll eventually reach a point where the rotors can get hot enough to melt parts and ruin wheel bearings.
  3. If your pedal goes all the way to the floor when you brake, you likely need better brake fluid and better cooling because you boiled the fluid.

Now, with all that said, I want to make something clear: I’m not saying that bigger brakes are useless or that you will not thoroughly enjoy them. I could name offhand five or ten IS owners who have upgraded to either the Supra TT or the LS400 calipers and they’ll rave about their setup. My only goal with this write up is to make clear that your brakes and tires have an intricate relationship, and you cannot expect to stop well without both being of good quality.

Upgrading to bigger brakes is definitely helpful for people who plan on exceeding the stock/bolt-on power rating (ie: boost), but even the naturally aspirated folk out there can appreciate the improved “bite” that a BBK will provide. Just make sure you have proper quality tires to match!


Once and for all: stereo options for your IS300

I see questions on this topic all the time: installing an aftermarket head unit in the IS300. There are many options, but it seems that many questions still remain. I plan to give an overview of some of the options available to you and hopefully clear up any lingering confusion. This won’t be a step-by-step guide as much as comprehensive information about the methods available to you. My advice is to pick the one that you feel most comfortable with and best suits your goals. 

1. Probably the most well-known solution is the Metra Tyto-01 harness, which connects your new headunit to the stock amp, allowing you to keep all 4 OEM speakers in place (though you can upgrade the speakers at the same time, if you wish). Many people opt for this method because it doesn’t require a new amp, it doesn’t require 2 new rear speakers, and it can be done fairly quickly. In summary: the RCAs come out of the headunit, plug into the Tyto box, and then a harness comes off of that and plugs into the stock harness feeding in from behind the glove box. You have to take the blue (in most cases it’s blue, but I can’t speak for every single stereo system) illumination wire off the new headunit and splice it into the illumination wire on the IS harness. Don’t forget the ground, or else your stereo won’t work properly and you’ll have to pull it all apart again.


Personally, I don’t quite understand the hype about this option because most have the intention of keeping the OEM system. If you plan on adding a real amp and new speakers, my opinion is that option #2 (which I will get to in just a sec) is easier, but we all have our preferences. The main reason I don’t like the Tyto option is because it involves keeping your stock amp (and in many cases, the OEM speakers), which to me is the weakest link of the OEM system. Most people go through all this and come out with really no improvement to sound quality, which seems to be more work than it’s worth. But, it makes for a simple install of your new and modernized headunit, which for some people is enough. For those of you going this route: don’t overthink it. It’s designed to be simple and quick.

2. Another option you have to renovate your sound system, though it requires a bit more hands-on work, is a separate Metra harness, the 70-8116. This harness will allow you to eliminate the stock amp (and preferably add one of your own, one that can actually push some decent power) while still retaining the stock speaker harness. I recommend installing a new headunit as well; I don’t see the point in going through all the work only to keep the OEM unit. This is important: it requires new rear speakers or you could fry your new headunit/amp. There are probably multiple ways to carry this out, but I opted to run power from the battery (with inline fuse) to the headunit & a switched power wire to the illumination wire on the headunit (you will need this or it won’t turn on); dual RCA cables, activation signal, & single power cable to my amp (grounded the amp in the trunk); and the Metra harness from the amp back into the stock speaker harness location (behind the glove box where the amp used to be). Since the stock rear speakers have four wires feeding into them, you’ll either have to slightly repin the Metra harness or pay attention to what wires are “hot” in the rear and which are not. Wire in the speakers accordingly.

I chose this method for two reasons: 1) I have a 2001, so the Tyto harness is not quite plug-and-play, plus I didn’t feel the Tyto setup was sufficient for what I wanted; 2) The stock amp does not allow the speakers to come anywhere near their potential, and once you put actual power to them you’ll see that they are indeed decent speakers. Even if you run your front speakers straight off the new headunit (without a new amp), you’ll notice that they will sound much much better than they ever have. I installed new 6x9s in the rear, and I will eventually upgrade the two fronts, but for now I’m pretty satisfied.

3. Your last option, which is the most labor-intensive and will turn some people away, is to run your own wires from headunit to amp to speakers and subwoofer (if applicable). For the audiophiles out there, this is the best option to achieve optimum sound quality, as you’ll be able to upgrade to a thicker gauge wire. While it might require the most elbow grease, it’s theoretically the simplest way. You’ll need power and ground coming off the battery (with an inline fuse) to your new headunit; you’ll likely have to run the activation signal from HU to amp; you’ll have to route the RCAs to your amp (presumably located in the trunk; amp will need its own power and ground as well), and lastly you’ll run wires from the amp to your speakers and subwoofer. No Metra harnesses, no nothing. You have a blank canvas to do and create as you please. FYI: Crutchfield has a great chart to help you guys determine what gauge wire you’ll need for your power goals right here.

So there you have it. If you’re looking to install a new headunit (and more) into your IS300, here are your options. Hopefully, I’ve eliminated some of the lingering confusion and misinformation that litters the interwebs. Have fun and go nuts.

Note: the first two options do not include directions on adding a subwoofer; if you are wiring everything yourself, this doesn’t matter.

So, you’ve got $2000 and you’re thinking about boost?

So, you’ve got yourself $2000 and you want to make your IS300 faster. Let me guess – you’re thinking about the CXRacing turbo kit. You’ve read great reviews and you’re ready to “pull the trigger,” eh? Sound about right? Or maybe you think you’re smarter than the average joe – you’ll buy the kit and upgrade the most important parts. Pretty clever, huh?

Take it from me, that’s $2000 that could — and should — be put elsewhere. If you’re serious about putting down power, then you need to build a good foundation. In stock form, the IS300 is a respectably sporty car. It goes without saying that the 2jz-GE motor is a great platform to start with. However, there are certain areas of the car that you really should look to improve before you dump money into forced induction (not to mention, it’s my opinion that the CXRacing turbo kit is an example of being pennywise and pound foolish).

If forced induction is really what you want, don’t go into it with a fixed number like $2000 in your head. Yes, the IS300 can be boosted for less money than other cars (though not as cheaply as Civics and the like), but your build should not be limited by your budget. I understand that not everyone has super deep pockets, but here is an example: let’s say you picked up an almost-finished turbo setup for a steal of a deal, but it comes with an outdated management system like the Unichip. You take it over to a friend’s house for him to look it over, and he says that you should invest in a quality management unit. If your reply is, “I don’t have the money for that right now,” that’s a red flag. You don’t need every single goodie available for the car, but your budget should not limit the reliability and safety if your build. If you want forced induction, wait until you can truly afford it.

Now, just because you don’t have the money for forced induction doesn’t mean you can’t improve your car. Like I said earlier, you can and should take that $2000 you have and invest it into building a solid platform. Before you do anything, you should be sure that your maintenance is taken care of. With the mileage and years on our cars nowadays, chances are there is an area or two (if not more) that needs your attention. When you have confirmed that your car’s maintenance is up to snuff, proceed reading this article.

Without further adieu, I present to you – the four (technically five) best modifications you can do to your IS300 with a limited budget. Not only will these additions improve your smile-per-gallon ratio, but they’ll also provide you a car that is far more reliable and enjoyable once boosted.

  1. Quality tires. I cannot stress enough how important these are. Having quality tires will not only increase your car’s performance abilities, but it also will make your car safer. Many people have debated how important big brake kits are to a car’s stopping ability, but what is often forgotten is the grippiness of the car’s tires. Simple physics will tell you that friction is the force that stops a car. If you lock up your OEM brakes when attempting to stop, there is nothing more that a big brake kit will do to help. When your brakes are locked, it’s up to your tires to do the rest. Having poor quality tires will greatly hamper your ability to stop, possibly putting you in a dangerous situation. Again, I cannot stress that enough. 
  2. Sway bars. Some call them anti-roll bars, but the point of them is to influence your car’s handling characteristics. Simply and generally put, the stiffer the sway bars, the more easily they will induce oversteer. What specifically does each sway bar do?
    1. Softer front bar: will increase front chassis roll; will increase front grip/traction, while decreasing rear grip/traction; will provide slower steering response; increases off-power steering in corner entry.
    2. Stiffer front bar will: decrease front chassis roll; decrease front traction while increasing the rear (aka, understeer); provide faster steering response; decrease off-power steering in corner entry.
    3. Softer rear bar will: increase rear chassis roll; increase rear grip, while decreasing front; decrease on-power steering.
    4. Stiffer rear bar will: decrease rear chassis roll; decrease rear traction, while increasing front traction (aka, oversteer); increase on-power steering.

Even a stiffer rear sway bar will noticeably increase your car’s sportiness. It might not add gobs of power, but sway bars make a huge difference on this car’s driving characteristics. Your car will feel flatter and more confident in each turn, thus allowing you to hit them harder and faster than you ever imagined (assuming, of course, you’ve taken modification 1 to heart).

3.  Whether you prefer coilovers or a shock/spring combo, you’ll find yourself reaping the benefits time and time again. Upgrading to adjustable suspension will allow you to fine tune your car’s driving characteristics to suit your exact needs. Track day? Switch over to a stiffer setting to maximize traction. Daily driver? Even if you set it back a bit softer, you’ll still have better handling than stock. While this upgrade isn’t exactly necessary, it’s definitely not something you’ll regret. Upgraded suspension coupled with upgraded sway bars will give you lots of flexibility for adjustments.

4.   Valve body upgrade. The “Toyomoto” style valve body rods were the first attempt at this upgrade, and they essentially remove any dampening between shifts. They do slam into each gear, and going into reverse can be rough. Since no company ever sold a stiffer spring to replace the OEM version, shimming the valve body is the best available budget-friendly option. Depending on what materials you use, the shims themselves could be free or very close to it (however, you will need to buy new transmission fluid). The shims make each shift noticeably more firm, but they preserve some of the stock dampening, so you won’t be jolted going into reverse or chirp your tires going into 3rd gear. Be sure to add a cooler when you do this mod, and you’ll have a stronger, much more capable transmission on your hands. We go into more detail of this upgrade here.

4a. For the manual guys – Figs Clutch Damper Device Delete. Essentially, it will improve the engagement of the clutch by removing the fluid restriction to the clutch slave cylinder. They go into more detail on this mod on their website, but at only $32, it’s certainly a budget-friendly mod with a lot of upside. Low risk, high reward as they say. This “mod” might not be as immediately noticeable as the valve body shims, but for the price it’s hard to beat it.

So, there you have it. Let’s say you spend $800 on a shock/spring combination, $500 on grippy summer tires, $400 on sway bars, and $40 on either the valve body upgrade or the CDD delete, and you’ve now spent less than you were going to spend on a suspect turbo kit and substantially improved your IS300.

So, you’re thinking about headers?

Headers are probably one of the most debated topics for the IS300 platform. There are lots of reasons to buy them – some of them good, some of them bad. Most likely you’re considering headers because you want to gain power or because you want to increase your exhaust sound… right? Or, maybe your cats are clogged and you just need something to replace them.

Whatever the case may be, you’ll benefit from a better understanding of each style of header and what each style does. There are two main types of headers: long-tubes (often associated with equal length headers) and short-tubes (aka: shorties).

Long-tube headers: Because of their design, long-tube headers are known to produce power in the mid-to-high RPM range. Long-tube headers have lengthy individual runners coming out of each exhaust port, and they typically merge into a common collector (also called a “dump collector”). As a result, the scavenging effect takes place later, which will produce the most power “up top.” This provides for a lot of potential for peak horsepower, but waiting until 4000 rpm and above can be miserable for a street-driven car. Now, for a high-quality set of long-tube headers (such as the original Mazzuri product or the Team Lexus race header) this doesn’t hold true. The Mazzuris made gobs of power of top, but they also improved the entire power-band, though they are quite raspy. Another example of this is the Dezod Development header (either Red or Green), which features their twin 3-1 hand crafted low angle merge collectors and their much-hyped 6-2-1 design. The Megan Racing headers are nowhere near the level of the Dezods or Figs Engineering (or even any of the “OG” headers), for the record. I’ve attached the dyno sheet from Dezod’s website for their Red headers, and as you can clearly see, not only is peak power significantly improved, but also the midrange power is substantially improved. You won’t get this with a cheaper header. Period.

Short-tube headers: If you peek under your hood, you might notice that the factory headers are a form of short-tubes. This is to maximize low-end torque (aka: usable power). As a result of the shorter runners, the scavenging effect occurs earlier and is less drastic. You might find that you’ll make less peak power, but you’ll have most of your power before a car with cheap long-tube headers even starts making any (again, with a high-quality set of long tubes this doesn’t apply). So if you’re racing from a dig, unless you have a very high stall torque converter, the car with the short tube headers is going to pull away from you in a hurry. With a short tube header, you’ll exceed the stock low end power, but you won’t make as much up top. 

Okay, so now that you have an idea of what these two popular header styles do, which one should you buy? Well, frankly, you need to take these characteristics and apply them to what you wish to accomplish.

Megan Racing’s header is probably the most well-known example of the long-tubes, mostly because of its price. Speaking from experience, the Megan header does indeed provide an increase in power, but the power does not come where it’s needed. Due to the low amount of R&D and quality control that is inevitable at its price point, the scavenging effect is not as well utilized as it could be. It makes power, but it leaves a good amount on the table: power you’re not going to find for $200. In addition, waiting until 4000 rpm for the catless header to overcome its lack of backpressure can be quite annoying.

On the other hand, Dezod Development offers a high-quality, American-made long-tube header for our platform. Another American company, Figs Engineering, recently released their own stepped-primary race header. As it is so new, I have not yet come across a dyno sheet for the Figs model, but it’ll compete with the Dezod models, and Mike (Figs) is putting in tons of hours getting them ready. These two headers are the cream of the crop, but many of today’s IS owners say that they’re “too expensive” or “not worth it.” Frankly speaking, if you want to gain power through headers, you’re going to have to open up the wallet a little bit. The saying “pay to play” holds true, and I stand behind it.

OBX headers are something to consider, but even then they’re not ideal. While not a ton of R&D went into their development, they fairly mimic the OEM design, and as such provide a small bump in your usable low end torque production. Realistically, a very high percentage of IS300s on the road today are street cars. Sure, many are track beasts, but for the average IS300 owner, power is needed down low. It’s not often you get above 5k RPM unless you’re really pushing the car. As such, it is more effective to have less peak power, but a large percentage in the low-to-mid range (speaking in terms of a street driven/daily driven car). If you truly want to make good gains, you’ll have to actually spend some decent money on headers.

Now, as I said, both styles of headers will gain some power. Their style (short or long) will determine where that power is gained. Neither will gain something crazy like 50 horsepower, which raises the question: are headers truly worth it?

I can say from personal experience that Megan headers are not worth it. The power band is so much better on stock headers (unless you only plan on running the expressways, in which case Megans might suit you better), especially when tuned. OBX headers will provide a small bump in low end umph, but if you’re looking for true gains with headers, then you need to either source a used set of Mazzuris or Xerds (as they’re both discontinued), or you need to purchase a new set of Dezods or Figs headers. The fact of the matter is that you’re not going to get high-quality power with a low-quality product.

Both Figs and Dezods are impressively high-quality, and offer the best overall power increase. Yes, they are indeed more expensive, but you’re paying for hours upon hours of R&D, in addition to build materials and rather impressive performance gains. For most people, paying real money for headers is out of the question, except for the naturally-aspirated purists. If you’re serious about making good old naturally-aspirated power in your IS300, then you’re going to have to look beyond the price. Megan Racing and OBX headers just won’t cut it.

Note: If you plan on installing catless headers, you will need an o2 simulator or delete. Spacers and foulers are the cheap way to solve the issue, and they are hit-or-miss. If you’ve been listening long enough and you understand that cheap headers won’t cut it, why even bother trying the cheap route to resolve your Check Engine Light?