Possible for our FA20s to have the Torque Curve of the FA20DITs?

[brzfl]

I'm looking into supercharger and turbocharger options and compared the dynos to the dynos of the 15 WRX which makes peak torque at 3.1k RPM. Is there any way for our FA20s to make as much torque down low? What kit would give me the best chance?

I'm currently comparing the Edelbrock SC to the AVO turbo kit, but I'm hoping there's some way to get a similar torque curve.


Here's the dyno I was looking at:

[Kodename47]

If you want that many torques down low, build the engine and pick a big enough turbo.

[Fred E]

Originally Posted by Kodename47

If you want that many torques down low, build the engine and pick a big enough turbo.

On the contrary, I think you'd need a really small (twin scroll) turbo that spools pretty much instantly like the FA20DIT's turbo does.

My '16 WRX is rather fun to drive, but I'd take my turbocharged BRZ over my WRX any day, despite the BRZ not having all that low down torque. The WRX (in stock form) kind of falls on its face after 4k RPM because the OEM intercooler is pretty terrible.

The twin-scroll Full Race turbo kit does spool rather quickly and gets pretty close. You even might be able to switch to a smaller turbo that would be even more responsive and move the torque curve even further down the X-axis. Velox Motorsports is a good team to have that discussion with: https://www.velox-motorsports.com/pr...race-turbo-kit

[Summerwolf]

Originally Posted by brzfl

I'm looking into supercharger and turbocharger options and compared the dynos to the dynos of the 15 WRX which makes peak torque at 3.1k RPM. Is there any way for our FA20s to make as much torque down low? What kit would give me the best chance?

I'm currently comparing the Edelbrock SC to the AVO turbo kit, but I'm hoping there's some way to get a similar torque curve.


Here's the dyno I was looking at:

Just curious, but why would you want a torque curve that starts high and falls off when the engine itself is reaching its natural powerband?


To get that kind of powerband I believe the works turbo kit is the closest, based on the few dyno sheets out there. Although the kit was widely criticized for the drop off in power in higher RPMs.


PTuning, Edelbrock, Vortech....right off the top of my head, there are others I'm sure....they all put torque down low and continue the natural powerband of the engine without a huge amount of drop off at peak.

[GsxrMe]

Fred E is spot on. Twin scroll spools much faster.

Seeing the BRZ, FRS or 86 isn't 4WD we have a huge traction issue, even down low. Im also ok not getting instant boost. As long as I hear the turbo spooling at 3k im happy.

I personally want a 2018 WRX (FA20). I would slap flex fuel kit on it. But like our cars the rods dont look much better. :<

[Icecreamtruk]

Would a Garrett GT2860RS be consider small enough that it would have good torque early? Maybe not 3k, but say full boost at 4k or so?

[GsxrMe]

They do sell Twin Scroll housings but that also requires a Twin Scroll header.

http://www.atpturbo.com/mm5/merchant...Category_Code=

[Alltezza]

JDL has a twin scroll turbo kit, although I don't know how our cars would handle that much TQ down low.

[Xero-Limit]

It acheives that torque curve with a less aggressive cam profile and it has smaller valves and ports to keep air velocity up on the low end. The turbo is also TINY and a twin scroll unit. For all these reasons it is a great car to drive around town, but falls flat on its face after 6200 RPM. This kind of power curve is also very hard on the motors since there's tons of torque which stresses the rods substantially, but overall the car feels pretty slow because of the low HP number. But it is effortless to drive with no turbo lag after 2500 RPM. I'd rather have a BRZ motor with an AVO or Edelbrock kit any day. They make great power where you want it, and if you want the power you should be above 4000 RPM anyway to go easier on the rods.

[Fred E]

Originally Posted by moto-mike

It acheives that torque curve with a less aggressive cam profile and it has smaller valves and ports to keep air velocity up on the low end. The turbo is also TINY and a twin scroll unit. For all these reasons it is a great car to drive around town, but falls flat on its face after 6200 RPM. This kind of power curve is also very hard on the motors since there's tons of torque which stresses the rods substantially, but overall the car feels pretty slow because of the low HP number. But it is effortless to drive with no turbo lag after 2500 RPM. I'd rather have a BRZ motor with an AVO or Edelbrock kit any day. They make great power where you want it, and if you want the power you should be above 4000 RPM anyway to go easier on the rods.

I think 6200 RPM is pretty generous actually!

[brzfl]

Originally Posted by Summerwolf

Just curious, but why would you want a torque curve that starts high and falls off when the engine itself is reaching its natural powerband?


To get that kind of powerband I believe the works turbo kit is the closest, based on the few dyno sheets out there. Although the kit was widely criticized for the drop off in power in higher RPMs.


PTuning, Edelbrock, Vortech....right off the top of my head, there are others I'm sure....they all put torque down low and continue the natural powerband of the engine without a huge amount of drop off at peak.

The torque curve of the Works looks really interesting to me, although it does fall off near the higher RPMs, I'll look into that for sure!

Originally Posted by moto-mike

It acheives that torque curve with a less aggressive cam profile and it has smaller valves and ports to keep air velocity up on the low end. The turbo is also TINY and a twin scroll unit. For all these reasons it is a great car to drive around town, but falls flat on its face after 6200 RPM. This kind of power curve is also very hard on the motors since there's tons of torque which stresses the rods substantially, but overall the car feels pretty slow because of the low HP number. But it is effortless to drive with no turbo lag after 2500 RPM. I'd rather have a BRZ motor with an AVO or Edelbrock kit any day. They make great power where you want it, and if you want the power you should be above 4000 RPM anyway to go easier on the rods.

So correct me if I'm wrong, if I go with a bigger twin-scroll turbo as I'm beginning to sense I'm going in the wrong direction, it would give me a good balance between low end torque and good power on the upper limit with headroom to grow with a built motor?

Originally Posted by Fred E

On the contrary, I think you'd need a really small (twin scroll) turbo that spools pretty much instantly like the FA20DIT's turbo does.

My '16 WRX is rather fun to drive, but I'd take my turbocharged BRZ over my WRX any day, despite the BRZ not having all that low down torque. The WRX (in stock form) kind of falls on its face after 4k RPM because the OEM intercooler is pretty terrible.

The twin-scroll Full Race turbo kit does spool rather quickly and gets pretty close. You even might be able to switch to a smaller turbo that would be even more responsive and move the torque curve even further down the X-axis. Velox Motorsports is a good team to have that discussion with: https://www.velox-motorsports.com/pr...race-turbo-kit

Loving the idea of this kit, although it is a bit more expensive that I'd hope to go, definitely an option

[GsxrMe]

Nothings cheap about going Turbo, after the kits install the supporting mods will add up. If you dont have 10k ready, i wouldnt.

[-Willis-86touge]

What about sprinted 335 kit close as I can think of.

[brzfl]

Originally Posted by -Willis-86touge

What about sprinted 335 kit close as I can think of.

Was definitely thinking of this kit, I just wanted to boost now and build later which is why I wasn't leaning to heavily towards this kit, but it might be more cost effective to just do it all at once.