Forced induction's affect on the nature of the 86
 

I just wanted to share my opinion on how forced induction affects the nature of the car. Last weekend I took the car around Watkins Glen as part of their thunder road tour. It was three laps behind a pace car, no passing allowed, but I was able to open it up through a few sections and really got a good feel for the car on the limit. Let me preface this by saying I haven't done the same in a N/A car, but I think the car really needs the extra power. It has so much going for it chassis-wise already, but the extra torque you get from FI makes the car feel so more grown up.

I know there are a lot of people out there that say you'll blow up your engine if you put forced induction on it, but i think there is definitely a right way to do it. Not too much psi, especially at lower RPM, and supporting mods like a catch can will help keep the engine internals happy. Honestly, the car doesn't need a whole lot more power to really liven it up, but a little bump is exactly what the car needs.

If you are on the fence about getting forced induction, go for it already!

Changing the nature of the engine is a big deal to some. Like how the NA Caymans and Carreras are now smaller displacement FI engines, and for the Cayman with two less cylinders, some will cry foul, even if performance has improved. The current Cayman S is faster than the previous gen GT4, yet no one cares. Many miss their NA flat six. They miss ringing out the power, being forced to wind up the engine, to hold the engine in high revs to keep it in power and maintain momentum.

I’ve gone FI for a number of reasons, but there is an argument not to go FI too, and for many, especially those not needing track, straight-away acceleration, who just want enough power to enjoy on the street, who want the challenge of ringing out all that a car has to offer, pushing it to its limits, the twins have enough power, and the engine’s characteristics are part of the enjoyment.

Having been in both places I felt with FI I had a self imposed restriction on how hard I pushed my car. Out of fear of going pop. As NA I love wringing it out for power. Both are fun though.

I must say I was surprised at how good the throttle response is. I was expecting some turbo lag but it wasn't there. I guess the fact the 12.5:1 2 litre limits you to a small and easily spooled turbo and that the static compression stays a high 12.5:1 at low rpms both really help.

That's a good point. I have owned cars that are easy to get to their limit and one can get a lot of satisfaction from keeping it there. I do tend to leave the traction control on because it keeps me from being too much of an idiot on public roads. I imagine I wouldn't be so apt leave the TC on without the supercharger.

*wringing

But, yeah... this car needs more power and boost is the cost effective, smart answer.

I’m not necessarily saying it *needs* more power... more like the whole platform is just *begging* for it. All of the dynamics are there and the engine can take a few pounds of boost no problem. For the price/effort/pay-off I think people should seriously consider it.

I met up with a forum member a little while back who had a series.yellow that was pretty much a track toy. I ‘forced’ him to take my car for a quick spin and I could tell he saw the light. If you can swing the financial end of it, I don’t think there is any better mod out there.

This. I've nearly gone FI a couple of times, but I enjoy being able to really wring the car's neck without worrying about the motor going... or getting arrested :D

There *are* times where the extra power would be fun, like moving through interstate traffic a bit easier. But in general it gets around just fine, and on the back-roads driving (most of what I do) I find I rarely can be pedal down for very long before I'm at illegal speeds, even NA (just header & tune basically) - so I'd really be frustrated with any more power. YMMV - on track if you're experienced and competing with some 'big boys' you'll certainly want more, just depends on where you are, what you do, and how much you're willing to risk/spend.

I think it depends on how and how much boosted. Since low rpm torque is not that high, I can say after thousands of miles that my JRSC engine with CARB tune is totally fine with wringing out for power from a reliability perspective. But, using the full power on public roads is reckless behavior given that car reaches unacceptable speeds above legal limits so quickly now.

If one wants to keep the nature of 86, I think a centrifugal/Rotrex supercharger is the best method to go FI. I still need to rev up to extract the power. It just gives linearly more power (and torque) as I rev up. It is the same car for me, just magnified. At low rpm, driving experience is closer to stock. Some want quicker throttle response (or low rpm torque) then twin-screw or turbo is what they want. But that changes the nature of 86 closer to a muscle car and increases the risk of engine fail.

FI affects the nature of 86, because you 'll drive it in general differently. Not that much of revving the engine, switching to correct gear etc.

How will FI make me rev less, or use the wrong gear?

That sounds like a driver error, not a FI problem.

I have it in my head that everything would just come quicker.


Shifting gears, reaching certain speeds, powering out of corners, etc.

Because it will! Trust me, I know everything about FI :bonk:

The platform definitely needs more power. That said, and just to offer a slightly different perspective, I have bought TWO WRX's (a 2015 and a 2018), and I'm glad Subaru did not put that engine into the BRZ. While more power would be great, there are so many issues with the tuning that engine that I have no doubt it actually would make the car worse. I do hope I find a centrifugal blower and pro tune in my future...

The FI car is more forgiving. If you don't rev the NA car, then you are slow. It is not the same with FI. And I was referring mainly on street driving, not on track were the environment is more controlled and known. In the end it is always a driver error, but it depends also the car. Some cars will push you to be a bit better driver, some others to be more "lazy" driver ...

Not that I'm an expert, but I find it hard to believe a FI car would be more forgiving. Not revving out the engine is on the driver. I also see a lot of fail videos and stories of those on the street.

Would definitely agree. I had the Edelbrock SC and have ridden in other FI cars (Vortec, Jackson, AVO and PTuning). Almost always, the SC'd car kept the overall character of the car, keeping the power delivery more linear, while the turbo'd cars just never felt "right".


The Synergy V8 on the other hand... well, that's a whole nother ball game lol




I didn't notice this until I parted out my car and was back to NA. I found that I was way more cautious with the car when I was FI and, as much fun the extra power was, I had forgotten how rewarding it was to just not give a F and wring the cars neck lol #stockisbest

You don't need to tune, just buy JRSC and keep JR CARB tune. It is excellent, silky smooth and efficient.

FI forgiving? :bellyroll:, yea, try to exit that turn with a little more than necessary throttle (and your famous skinny tires). You will be going backwards.

It is not driver error. It is time in the saddle that changes. With a high powered vehicle, the time on the gas and moving through the rpms is shortened, in some cases, dramatically. You can be out of road or limited by the speed limit before you even had a chance to get into it. The trade off is having more acceleration, but acceleration isn’t everything, especially on the street.

https://youtu.be/FJ8R4tYbX5w

What issues are you having with tuning the FA20DIT?

I've had no issues with my WRX...

You said it yourself.

I don't think I'd call a FI twin high powered, unless it had the power to ratio of something in say.... GT3/GTR/Z06 territory.

a 300hp twin isn't exactly a fast car by modern standards. Quick? Sure, but not so fast that you're spinning tires at speed limits.

This is exactly why I keep the traction control on

Traction control is calibrated for the stock power, I guess. I noticed that it wasn't working as effective with increased power. After I have installed wider (245/40-17) tires with more grip, I was able to depend on traction control again. The best is always controlling your throttle and speed at corners though; traction control doesn't save every situation.

Sorry, replace high with higher, so what I said can make sense. A higher hp or higher power to weight ratio car will always have less time wringing out the rpms, whether it is 0-60 or just banging through a set of gears. It is like riding a roller coaster versus doing a drop zone—variable and longer, but less intense versus fast and intense but quickly over. This is kinda like the Cayman NA vs turbo argument too; character and thrills versus just more power. On the street, some might prefer an 86 that is NA for those reasons.

I'm very happy with my Sprintex kit so far. I'm stock everywhere else so the car is definitely faster but not massively faster. Just a lot more midrange. I don't think it changes the character of the car too much, it just makes it not frustrating anymore and actually slightly intimidating when you push it, but that's how I wanted it. In my opinion I've just rounded out the car whereas before the power was the weak point.

I would also like to know what issues. My WRX with E50 flex and full bolt ons is a completely different car. Who was your tuner?

Where did you see in the discussion about trying to exit a turn?

I was mentioning this in the context of revving the car and having the correct gear. An FI car is more forgiving if you have a wrong gear, because it has a better and broader torque curve. It will pull better and you'll have enough torque even with a higher gear. It is not uncommon that so many drivers complain about the torque dip in stock cars. Most of them they don't use the correct gear and many of them were used to drive like this because of older FI cars or bigger engine cars.

I should have been more clear since both of you misunderstood my comment. I have not tried to tune those cars, I was commenting on the stock tune.

Subaru's tuning of the FA20 turbo in the WRX is beyond terrible. It's really incredible how bad it is, which is why I'm glad they did not do that to the BRZ. Selling a car that benefits from a tune, I can understand (GTI, FocusRS, etc.). Selling a new car that requires a new tune is dumb.

I imagine a JRSC would work great (post-warranty LOL).

No it isn't. Wrong gear is wrong gear, period. The guy in the right gear will go faster, FI or not.

Tell this to the people who go FI, because they don't like to downshift constantly for an overtake. Maybe you have in mind only race track driving. On ordinary road there are different driving scenarios. I am not saying here which is good or bad. What I am saying is that going FI changes definitely the nature of the car.

It's your discussion, not mine.

Is there something wrong with not downshifting?

Nothing is forgiven, error is error, wrong gear is wrong, lost speed is lost, FI or not. FI drivers are not dummier than NA drivers, if you mean that.

You'll lose less time with a stronger car. I think it is quite obvious. It seems to me that we are arguing here just for the sake of argument.

Agreed :) Let's stop :cheers:

I'm gonna let you think about that one :D

That's still NA :cheers: :bellyroll:

No. You drew first blood.

I blame Ambien!