|
Scion FR-S / Toyota 86 GT86 General Forum The place to start for the Scion FR-S / Toyota 86 | GT86 |
|
Thread Tools | Search this Thread |
04-28-2014, 12:55 PM | #1 |
Senior Member
Join Date: Mar 2014
Drives: swp brz limited
Location: ca
Posts: 205
Thanks: 30
Thanked 81 Times in 46 Posts
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
|
purpose of torque dip
The more I drive this car the more I realize how much thought was put into the engineering. Lately I find myself on empty twisty canyon roads skiing around. I realized that, at times, the torque dip might be useful. It seems to provide extra fidelity in the throttle which is nice at the limits of ashesion. If I am in the upper power band coming up on a turn and let off gas and begin turn. As the weight shifts and I hear the car say yes you may wag my tail I agree. And I find that in the "dip" is a perfect range of power to add more overseer or back off.
But because of the dip in torque it seems like that range of power is ideal for an extremely light car at the limits of adhesion. It doesn't need much at the limit and I believe this car is so well engineered that may have been thought out. rather than just some terrible thing someone overlooked. Or maybe I'm in love with a girl with glasses |
04-28-2014, 01:08 PM | #2 |
Undisputed El Presidente
Join Date: Jun 2012
Drives: Zenki 37J ZN6
Location: Stockton, CA
Posts: 11,571
Thanks: 9,382
Thanked 9,397 Times in 5,261 Posts
Mentioned: 374 Post(s)
Tagged: 33 Thread(s)
|
The prupose is MPG. I find driving in the dip is harder myself. No response from the go peddle when you need it.
|
The Following 3 Users Say Thank You to finch1750 For This Useful Post: |
04-28-2014, 01:09 PM | #3 |
Senior Member
Join Date: Jun 2013
Drives: 2013 Raven fr-s
Location: Southwest Florida
Posts: 450
Thanks: 193
Thanked 176 Times in 99 Posts
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
|
You may be in love with a girl with glasses...a hot, skanky one...
|
The Following 4 Users Say Thank You to Basket Case For This Useful Post: |
04-28-2014, 01:09 PM | #4 |
Senior Member
Join Date: Jul 2013
Drives: 2013 Scion FR-S Firestorm
Location: The Ramapo Mountains NJ
Posts: 248
Thanks: 212
Thanked 155 Times in 94 Posts
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
|
The dip in torque between 3500~4500 rpm wasn't something they engineered in because they thought it was a good idea or would add to the fun. It's (likely) there in order for the car to meet emissions and possibly fuel economy requirements. I like girls with glasses. But I don't find this one particularly likeable.
|
04-28-2014, 01:11 PM | #5 |
Senior Member
Join Date: Aug 2012
Drives: FR-S
Location: IL
Posts: 2,857
Thanks: 519
Thanked 2,997 Times in 1,095 Posts
Mentioned: 159 Post(s)
Tagged: 1 Thread(s)
|
There had to be a reason they tuned it that way aside from efficiency. I mean the SAE articles and testing from Subaru show DI/Port injection maps with the TQ dip there. They knew it was there and left it.
I have heard so many reasons why and how, but still am not convinced.
__________________
|
04-28-2014, 01:41 PM | #6 | |
Senior Member
Join Date: Jun 2013
Drives: 2013 Raven fr-s
Location: Southwest Florida
Posts: 450
Thanks: 193
Thanked 176 Times in 99 Posts
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
|
Quote:
|
|
04-28-2014, 02:28 PM | #8 |
Chief
Join Date: Feb 2012
Drives: 2013 DGM BRZ Premium 6MT
Location: USA
Posts: 573
Thanks: 145
Thanked 178 Times in 126 Posts
Mentioned: 8 Post(s)
Tagged: 0 Thread(s)
|
To mimic VTEC, but at 5,000 RPM instead of 7,000 RPM?
|
The Following 4 Users Say Thank You to Eurasianman For This Useful Post: |
04-28-2014, 02:52 PM | #9 |
Senior Member
Join Date: Apr 2011
Drives: miata, mazdaspeed protege, ls430
Location: socal
Posts: 4,416
Thanks: 599
Thanked 1,442 Times in 787 Posts
Mentioned: 28 Post(s)
Tagged: 0 Thread(s)
|
Implying the torque dip was engineered to be there is silly. I'm sure they knew it was there but I believe that getting rid of it would cause some other compromise the team would dislike even more
|
The Following 5 Users Say Thank You to fatoni For This Useful Post: | 86-tundra (04-29-2014), Ammonia (04-28-2014), coredump4 (04-28-2014), FRSBRZGT86FAN (05-01-2014), shishand (04-28-2014) |
04-28-2014, 03:03 PM | #10 |
Senior Member
Join Date: Feb 2012
Drives: 2017 Subaru BRZ PP
Location: Florida
Posts: 1,525
Thanks: 1,702
Thanked 646 Times in 317 Posts
Mentioned: 8 Post(s)
Tagged: 0 Thread(s)
|
SWP, I originally suspected that may be the reason too. In MotoGP, the crossplane crankshaft was designed to give the engine short breaks in power in order to retain more grip when power sliding. However, this is isn't the same sort of thing and the car doesn't have much power to begin with. They'd be better off giving it more grippy tires to compensate for a little more power if that were the case. I'm pretty sure the dip was just a compromise. I just hope they get rid of it for next year.
__________________
Toyota + Subaru =
|
04-28-2014, 03:13 PM | #11 |
Senior Member
Join Date: Dec 2013
Drives: '13 BRZ Limited WRB Phantom ESC 1.5
Location: Middleport, OH
Posts: 720
Thanks: 277
Thanked 243 Times in 165 Posts
Mentioned: 7 Post(s)
Tagged: 0 Thread(s)
|
Come on, guys. I don't really get everyone complaining about the torque dip all the time. The problem is easily resolved by downshifting. Sure, the dip is there. But no 2.0 liter 4cyl I am aware of makes any significant torque at lower rpms without FI. The VTECs mentioned above aren't any different. My Prelude VTEC didn't have any significant low end torque, either. Whether or not it had a dip in a nearly non-existent amount of torque wasn't really relevant to me. I just rev'ed it out from 5,000 to 7100 in each gear... and it moved along nicely. In fact, the numbers showed it was a quick from 60-120 as a Mustang GT.
Seems to me that everyone basically has 5 options: 1: Use the power and torque where it exists - which is 5000+; 2: Get a tune (which broadens the spread significantly); 3: Get FI; 4: Get a larger motor and/or a Camaro/Mustang; 5: Get a header (with a tune). If you didn't want to shift a lot, then you probably shoulda had a V8.
__________________
'13 BRZ Ltd MT WRB Phantom ESC 1.5
2012 Honda Accord Coupe 2006 Saab 9-3 2.0t 1997 Honda Accord Coupe 1995 Honda Prelude VTEC Last edited by robwbright; 05-02-2014 at 12:14 AM. Reason: Add #5 |
The Following 9 Users Say Thank You to robwbright For This Useful Post: | BirdTRD (04-28-2014), Evil Jesus (04-28-2014), FRSBRZGT86FAN (05-01-2014), powerj2 (04-29-2014), schmearcampain (04-29-2014), Shadeslayer (05-25-2017), skuts? (04-29-2014), strat61caster (04-28-2014), Wander (05-01-2014) |
04-28-2014, 04:28 PM | #12 |
Senior Member
Join Date: Jul 2013
Drives: 2013 Scion FR-S Firestorm
Location: The Ramapo Mountains NJ
Posts: 248
Thanks: 212
Thanked 155 Times in 94 Posts
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
|
But that's not exactly correct. I think this engine is very torquey down low. Especially for a normally aspirated 2.0 liter. Around 2500 RPM it's actually pretty strong and surprisingly punchy. In fact, I don't think I've ever driven a car with a non F.I. engine this small, with so much bottom end torque on tap. The problem is that the torque falls off significantly around 3500 rpm. And that's why it's so noticeable.
|
The Following User Says Thank You to jjaisli For This Useful Post: | Shagaliscious (04-28-2014) |
04-28-2014, 04:34 PM | #13 |
Member
Join Date: Jul 2012
Drives: 2013 BRZ Limited MT, 2006 Spec.B
Location: Virginia, USA
Posts: 67
Thanks: 7
Thanked 10 Times in 7 Posts
Mentioned: 7 Post(s)
Tagged: 0 Thread(s)
|
|
04-28-2014, 04:36 PM | #14 |
Senior Member
Join Date: Jul 2013
Drives: Subaru BRZ Limited
Location: Austin, TX
Posts: 1,281
Thanks: 966
Thanked 538 Times in 319 Posts
Mentioned: 15 Post(s)
Tagged: 0 Thread(s)
|
I agree with robwbright. Drive the car in the higher RPM's if you don't like the feel of the torque dip, or just downshift. Seems easy enough to me.
__________________
|
|
|
Thread Tools | Search this Thread |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
What's the Purpose of WL Com C Top Mounts? | gbgracer | Tracking / Autocross / HPDE / Drifting | 16 | 03-27-2013 01:52 PM |
Thread with genaral purpose | TIE Pilot | Site Announcements / Questions / Issues | 2 | 03-07-2013 03:13 PM |
Purpose of alternator and a/c covers | Turbowned | Engine, Exhaust, Transmission | 3 | 03-03-2013 04:54 PM |
Purpose of oil catch can? | denverizzles | Engine, Exhaust, Transmission | 1 | 06-28-2012 03:55 PM |
What purpose or role will the FR-S / BRZ serve you? | switchlanez | Scion FR-S / Toyota 86 GT86 General Forum | 139 | 03-27-2012 02:28 PM |