|
Engine, Exhaust, Transmission Discuss the FR-S | 86 | BRZ engine, exhaust and drivetrain. |
|
Thread Tools | Search this Thread |
10-17-2017, 07:27 PM | #15 |
Kouki-Monster
Join Date: May 2012
Drives: 2013 Scion FR-S
Location: Saskatoon, SK
Posts: 1,137
Thanks: 11
Thanked 562 Times in 261 Posts
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
|
Light crank pulley is a useless and aesthetic mod pushed by lazy companies. Use OEM or use a proper piece like a Fluidampr pulley.
__________________
Rich Anderson
EMPOWER AUTO |
The Following 2 Users Say Thank You to empower-auto For This Useful Post: | mrg666 (10-28-2017), Somerandom18 (10-17-2017) |
10-28-2017, 05:00 AM | #16 |
Senior Member
Join Date: Feb 2014
Drives: BRZ 2018
Location: California
Posts: 119
Thanks: 116
Thanked 65 Times in 38 Posts
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
|
Technically, lighter pulleys, drive shaft, flywheel, and wheels all contribute to lower inertia and hence faster acceleration. In terms of effect on the angular inertia, per lb in weight reduction, the order of significance (from large to small) is:
(1) flywheel; (2) wheel; (3) pulley; and (4) driveshaft. Also, light weight lug nut will also help (ever so slightly). The incremental improvement of adding each of these light weight parts may not be so apparent. But the opposite is true: ie the result of replacing these light weight parts with their oem, heavier parts, is VERY apparent. It feels like adding a 100lb sack of potato to the trunk. Please remember none of these light weight part adds power, per se. They only reduce inertia of the drive train, and hence better acceleration (and deceleration). The effect is applicable at all times at any rpm. |
10-28-2017, 11:15 AM | #17 | |
Senior Member
Join Date: Jul 2014
Drives: 2020 Hakone
Location: London, Ont
Posts: 69,845
Thanks: 61,656
Thanked 108,283 Times in 46,456 Posts
Mentioned: 2494 Post(s)
Tagged: 50 Thread(s)
|
Quote:
__________________
Racecar spelled backwards is Racecar, because Racecar.
|
|
The Following User Says Thank You to Tcoat For This Useful Post: | mrg666 (10-28-2017) |
10-28-2017, 12:06 PM | #18 |
pessimistic skeptic
Join Date: Apr 2016
Drives: '14 FR-S Monogram AT JRSC
Location: Upstate NY
Posts: 1,767
Thanks: 1,695
Thanked 1,035 Times in 684 Posts
Mentioned: 14 Post(s)
Tagged: 0 Thread(s)
|
I generally avoid buying anything from those manufacturer brands which have such useless, and often overpriced, parts among their products.
|
10-28-2017, 12:41 PM | #19 |
Senior Member
Join Date: Mar 2014
Drives: '15 BRZ RA
Location: Greece
Posts: 3,787
Thanks: 2,416
Thanked 1,944 Times in 1,261 Posts
Mentioned: 29 Post(s)
Tagged: 0 Thread(s)
|
Which company is exactly lazy and overpriced? A company like the following one?
Yes, they have also lightweight pulleys and driveshafts. Because they are simpler mods and not anyone wants or willing to open the engine. Our ignorance, doesn't mean that they are useless. @OP: I like your mods. Unfortunately, the faster drop of RPMs requires faster gear changes which is not always optimal on a street car. Personally, I would choose as next mod the thicker rear axles. https://www.sti.jp/parts/subarubrz_z.../ST28421AS100/ |
10-28-2017, 01:58 PM | #20 | |
pessimistic skeptic
Join Date: Apr 2016
Drives: '14 FR-S Monogram AT JRSC
Location: Upstate NY
Posts: 1,767
Thanks: 1,695
Thanked 1,035 Times in 684 Posts
Mentioned: 14 Post(s)
Tagged: 0 Thread(s)
|
Quote:
Why would I start a discussion by giving names of manufacturers that I don't care about. I can give recommendations, though. How about my highest recommendation for Jackson Racing that increased my power to 300hp. Your turn. But no unsupported crap please. |
|
10-28-2017, 04:34 PM | #21 |
The Dictater
Join Date: Apr 2017
Drives: '13 Red Scion FRS
Location: MD, USA
Posts: 9,386
Thanks: 26,018
Thanked 12,389 Times in 6,120 Posts
Mentioned: 85 Post(s)
Tagged: 0 Thread(s)
|
See post 11. I didn't calculate pulleys because I was lazy, and I wasn't expecting more than 1hp return based on the other stuff. Was thinking of fixing up my drive line inertia calculator to make it easier to use and posting it. I just did a rough calculation once because I was curious.
|
10-29-2017, 01:31 AM | #22 |
Senior Member
Join Date: Mar 2014
Drives: '15 BRZ RA
Location: Greece
Posts: 3,787
Thanks: 2,416
Thanked 1,944 Times in 1,261 Posts
Mentioned: 29 Post(s)
Tagged: 0 Thread(s)
|
Cars are complex systems with many parameters and a physical model is an over-simplification. We cannot know the engine's potential, until we measure the effect of a specific kit.
Here are the gains of a pulley kit with a small under-drive on the alternator. The measurement was made on 4th gear by Toda: The gains are between 3-10 hp in the entire RPM range. You asked about numbers and you got it. I won't start a discussion of supercharger kits here. It is irrelevant to OPs topic. |
The Following User Says Thank You to nikitopo For This Useful Post: | Impureclient (10-29-2017) |
10-29-2017, 01:49 AM | #23 |
Banned
Join Date: May 2015
Drives: 2015 FR-S
Location: NPR, Florida
Posts: 2,404
Thanks: 1,802
Thanked 2,903 Times in 1,282 Posts
Mentioned: 25 Post(s)
Tagged: 2 Thread(s)
|
^ Graphs that say power increases with lightweight pulleys and Fluidampr ones that say it decreases. This is getting fun.
|
The Following User Says Thank You to Impureclient For This Useful Post: | ohmai18 (10-29-2017) |
10-29-2017, 01:58 AM | #24 |
Senior Member
Join Date: Mar 2014
Drives: '15 BRZ RA
Location: Greece
Posts: 3,787
Thanks: 2,416
Thanked 1,944 Times in 1,261 Posts
Mentioned: 29 Post(s)
Tagged: 0 Thread(s)
|
Fluidampr is a heavier pulley comparing to stock and has an entirely different function. I've seen respected Japanese tuners to use it on supercharged or turbo 86/BRZ cars for increased engine reliability. It is a good option if you are going with FI. On a NA car they are saying that it is not really needed.
|
10-29-2017, 02:06 AM | #25 | |
Not a troll
Join Date: Apr 2015
Drives: FR-S
Location: Canada
Posts: 5,104
Thanks: 8,237
Thanked 5,399 Times in 2,694 Posts
Mentioned: 266 Post(s)
Tagged: 4 Thread(s)
|
Quote:
|
|
10-29-2017, 02:25 AM | #26 | |
Senior Member
Join Date: Mar 2014
Drives: '15 BRZ RA
Location: Greece
Posts: 3,787
Thanks: 2,416
Thanked 1,944 Times in 1,261 Posts
Mentioned: 29 Post(s)
Tagged: 0 Thread(s)
|
Quote:
If you or other people can't get over of what they bought and searching about huge improvements it is not my problem. It is your problem. |
|
10-29-2017, 02:40 AM | #27 |
Senior Member
Join Date: Oct 2013
Drives: Subaru BRZ
Location: San Francisco
Posts: 245
Thanks: 180
Thanked 97 Times in 69 Posts
Mentioned: 7 Post(s)
Tagged: 0 Thread(s)
|
I asked Perrin if installing an ACT SB7 with Streetlite clutch, with a lightweight driveshaft, and with Perrin's three lightweight pulleys would damage the engine. Here's their response.
Thoughts?
__________________
Last edited by ohmai18; 10-29-2017 at 04:03 AM. |
10-29-2017, 04:01 AM | #28 |
Senior Member
Join Date: Mar 2014
Drives: '15 BRZ RA
Location: Greece
Posts: 3,787
Thanks: 2,416
Thanked 1,944 Times in 1,261 Posts
Mentioned: 29 Post(s)
Tagged: 0 Thread(s)
|
Yes in some older Subaru engines, if you were combing a lightweight driveshaft with a lightweight pulley you could get a CEL miss-fire code. It was known to happen if you were going lower than a specific weight. It wasn't known if there was an actual miss-fire or just the ECU was throwing a code. I've not heard something similar in our engines.
A final remark concerning different lightweight pulley kits. There are some cheap ones and some quite expensive. The difference is not related with the marketing department of each company, but the used material. You replace a steel pulley with an aluminum one and it is important to not have a failure. It is known that 7075 aluminum material is much better than the cheap aluminum, with a strength comparable to many steels. However, it is more expensive. So, you get what you pay ... Last edited by nikitopo; 10-29-2017 at 04:11 AM. |
|
|
Thread Tools | Search this Thread |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Lightweight vs OEM flywheel for FI | FirestormFlex | Forced Induction | 23 | 09-25-2019 07:49 AM |
Lightweight Driveshaft: worth it? | Admired | Engine, Exhaust, Transmission | 15 | 10-02-2018 05:55 PM |
ACT XT Street & Lightweight Flywheel | Weasel Soup | Engine, Exhaust, Transmission | 8 | 03-21-2016 11:46 PM |
Lightweight Flywheel + Crank Pulley: Bearing Failures? | Anthony | Engine, Exhaust, Transmission | 23 | 01-24-2015 12:10 PM |
Flywheel and Driveshaft | Admired | Engine, Exhaust, Transmission | 37 | 06-09-2014 12:46 AM |