The Ultimate FA20 ITB thread.

[CSG Mike]

Originally Posted by Quasimofo

And this right here is why I hate forced induction. I have never once driven a FI car that has that immediate throttle response that I crave in a fun vehicle.
If it doesn't have good throttle response, might as well slap an automatic on it and let the damn transmission sort it out.

Fingers crossed that this doesn't require a full ecu swap; I don't like having to dodge vehicle inspections 'cause the diagnostic port is a road to nowhere.

Sounds like you've never really driven FI done right!

[Quasimofo]

Originally Posted by CSG Mike

Sounds like you've never really driven FI done right!

Perhaps; I mean, I have never driven anything with a supercharger. But I'm really not sure a turbo'd engine can be made to feel acceptable to me. Always open to being proven wrong, but I'm a pretty big n/a fan. The faster the revs rise and fall the better. Make it feel as responsive as a superbike engine and I'm sold.

Which is why I'm here in the itb thread lookin' at parts that cost almost as much as a turbokit

[churchx]

Turbo is not the only way of forced induction (though even it can be made right with little to no turbo lag). Ever heard of supercharging?

[Lantanafrs2]

Originally Posted by Quasimofo

Perhaps; I mean, I have never driven anything with a supercharger. But I'm really not sure a turbo'd engine can be made to feel acceptable to me. Always open to being proven wrong, but I'm a pretty big n/a fan. The faster the revs rise and fall the better. Make it feel as responsive as a superbike engine and I'm sold.

Which is why I'm here in the itb thread lookin' at parts that cost almost as much as a turbokit

LS swap

[CSG Mike]

Originally Posted by Quasimofo

Perhaps; I mean, I have never driven anything with a supercharger. But I'm really not sure a turbo'd engine can be made to feel acceptable to me. Always open to being proven wrong, but I'm a pretty big n/a fan. The faster the revs rise and fall the better. Make it feel as responsive as a superbike engine and I'm sold.

Which is why I'm here in the itb thread lookin' at parts that cost almost as much as a turbokit

The fundamental concept of turbocharging means there will always be a delay, but that transient spoolup can be minimized.

With a proper clutch setup, a turbo will still be more responsive than a stock engine and tune that has excessive transient ignition retard.

Superchargers will have zero lag.

[Tokay444]

Originally Posted by Quasimofo

Perhaps; I mean, I have never driven anything with a supercharger. But I'm really not sure a turbo'd engine can be made to feel acceptable to me. Always open to being proven wrong, but I'm a pretty big n/a fan. The faster the revs rise and fall the better. Make it feel as responsive as a superbike engine and I'm sold.

Which is why I'm here in the itb thread lookin' at parts that cost almost as much as a turbokit

Thankfully, no automotive engineer on the planet gives a flying fuck what you feel is acceptable. Especially when there isn’t a single modern turbo that suffers from anything you could claissify as a lack of throttle response. Turbo cars can suffer from transient response, depending on the size of the turbo, but the throttle plate opens the second you mash the gas on pretty much all of them.
I’m going with, you just don’t know what you’re talking about. And that’s fine.
The speed with which revs rise and fall have absolutely zero to do with induction type. This is all relative to mass of the rotating assembly, including the flywheel. You’ve proven my point.
You’re free to like and dislike whatever you want, for whatever reason, but you should at least have an educated opinion.

[Lantanafrs2]

The thing can be responsive and still slow lol. Forced induction to make power, na to make a point

[Hawk77FT]

I am considering the ITB with velocity stacks, however I am still wondering how can we deal with the MAF sensor missing? Is there a way to trick the ECU?

[Quasimofo]

Originally Posted by Lantanafrs2

LS swap

Already got an LS7 in another car, don't want to step on any toes.
If I'm swapping motors, I'd sooner just sling a bridgeported 2 or 3 rotor in there so it would rev like a madman and scare people.

[Quasimofo]

Originally Posted by Tokay444

Thankfully, no automotive engineer on the planet gives a flying fuck what you feel is acceptable. Especially when there isn’t a single modern turbo that suffers from anything you could claissify as a lack of throttle response. Turbo cars can suffer from transient response, depending on the size of the turbo, but the throttle plate opens the second you mash the gas on pretty much all of them.
I’m going with, you just don’t know what you’re talking about. And that’s fine.
The speed with which revs rise and fall have absolutely zero to do with induction type. This is all relative to mass of the rotating assembly, including the flywheel. You’ve proven my point.
You’re free to like and dislike whatever you want, for whatever reason, but you should at least have an educated opinion.

Have you driven a current model STi? It does not have what I call "snappy throttle response." With throttles no longer being cable controlled, are you really getting the throttle opening you think you are? The base BRZ plays games with throttle opening to try to game that torque hole. But thats besides the point.

I'm also well aware what lighter flywheels do. I've run 9 and 11 pound units in other cars.
I don't like turbos. I prefer N/A. It's a free country.

At the end of all this, I just hope there's another useful product to spend money on.

[churchx]

With stock twins ecu tune/stock throttle mapping torque dip is there, i doubt there any games are played regarding that (otherwise i'd expect that to be hacked around/"fixed" by throttle remap in MY2017, as many complained about it in past for twins). But yes, throttle mapping is not linear, and judging by how it's done, imho game that is played in stock tune is to make impression of having larger engine, by actual throttle opening much steeper during first part of pedal travel. That doesn't affect so much how immediate throttle response is though, drawback being less fine low-medium open throttle control to pay for that bigger engine faking.
Still, as i already mentioned above - supercharging might be considered as option. It won't change a bit throttle response, which will same exactly same as in NA. With SC engine should behave same as NA except generating more power, like if engine had been NA but of bigger displacement (at cost of less efficiency due gearing/pumping losses from driven by engine supercharger, instead of more efficient turbocharging that is driven by recuperated energy of exhaust gases).
But imho lag of well done turbo setup that isn't concentrated on max output, but instead on little lag/quick spoolup from low rpms with single turbo optimized for low rpms or twin turbo (STI's setup is not such in my eyes, rather set for max power from engine, mostly at top) can be rather responsive, and you might be trying to avoid such too undeservedly.

[Tokay444]

Originally Posted by Quasimofo

Have you driven a current model STi? It does not have what I call "snappy throttle response." With throttles no longer being cable controlled, are you really getting the throttle opening you think you are? The base BRZ plays games with throttle opening to try to game that torque hole. But thats besides the point.

I'm also well aware what lighter flywheels do. I've run 9 and 11 pound units in other cars.
I don't like turbos. I prefer N/A. It's a free country.

At the end of all this, I just hope there's another useful product to spend money on.

There's a really easy way to find out of you're getting the throttle position you think you are. Log it.
For all else, see quoted post.

[drew_kar]

I would 100% sell my turbo kit to fund running an ITB setup. I hope they can utilize Ecutek and get everything figured out. I will be watch this thread closely. Going back to N/A would be ideal for me.

[Tokay444]

Originally Posted by drew_kar

I would 100% sell my turbo kit to fund running an ITB setup. I hope they can utilize Ecutek and get everything figured out. I will be watch this thread closely. Going back to N/A would be ideal for me.

Keep your turbo AND run ITB...