Discussion On Your Daily Ride

vr2turbo

Beyond 20,000 RPM!
Helmet Clan
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Never tried a manual with SI mode. The forester with CVT the S mode pushes the rev higher into the engine power range, therefore giving better throttle response and probably more fuel feed. Like cruising at 110kph I mode only 1.8k rpm, S mode is around 2.5k
 

YellowFlash

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Mark X compression is 12:1 but GDi engine, can drink 95 no problem. You can try 97 but IMHO not worth the price difference.



For Swift Sport is a bit misconception. The fuel Ron requirement is 95-98, so minimum can still drink 95 without issues. I have tried all ron but now I just use 95 for my son's Swift Sport. In UK, most people also just fill up 95 for it.
The modern ecu on most cars has the ability to adjust to lower Ron fuel by retarding the ignition timing however if the car’s manufacturer tuned it for higher Ron (per car handbook) then you are actually sacrificing some performance. The higher compression of these performance tuned engine can take advantage of advancing ignition timing to take extract more power but by using lower octane fuel, in context of RPG gaming (for illustration purpose) you’re basically like a level 20 character with a level 10 weapon. It’s always up to individual’s choice what they choose but I wouldn’t want to buy a high performance vehicle and then not enjoy it as much.
 

YellowFlash

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Never tried a manual with SI mode. The forester with CVT the S mode pushes the rev higher into the engine power range, therefore giving better throttle response and probably more fuel feed. Like cruising at 110kph I mode only 1.8k rpm, S mode is around 2.5k
Wow I didn’t know the ecu can alter the CVT’s ratio. For the manual, it basically just alters the throttle response, on the 6th gear at 110kph, rpm is about 2.5k.
 

6UE5t

6,000 RPM
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The modern ecu on most cars has the ability to adjust to lower Ron fuel by retarding the ignition timing however if the car’s manufacturer tuned it for higher Ron (per car handbook) then you are actually sacrificing some performance. The higher compression of these performance tuned engine can take advantage of advancing ignition timing to take extract more power but by using lower octane fuel, in context of RPG gaming (for illustration purpose) you’re basically like a level 20 character with a level 10 weapon. It’s always up to individual’s choice what they choose but I wouldn’t want to buy a high performance vehicle and then not enjoy it as much.
Yes but the difference in performance for my NA cars are barely noticeable so doesn't justify the price difference between the 2 Ron. Maybe I am old uncle already so butt not that sensitive anymore to such marginal difference. If true high performance sports car and turbo cars surely should have much more difference
 

RENESIS VIII

7,000 RPM
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View attachment 572847


Yet to get a boost control so far, so the only way to artificially control my boost is through the different SI-Drive modes which alter the throttle response affecting the boost level. The I-Mode which typically keeps my boost below 0.5 bar can feel quite sluggish to drive.
Nice. You that's a GRF chassis WRX STI isn't it? Since you mentioned 2.5
 

vr2turbo

Beyond 20,000 RPM!
Helmet Clan
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Wow I didn’t know the ecu can alter the CVT’s ratio. For the manual, it basically just alters the throttle response, on the 6th gear at 110kph, rpm is about 2.5k.
ECU already controls the CVT, right? Step on the fuel rev goes up, then slowly pick up speed until final ratio. The paddle shifters also changes the CVT ratio....
 

ixeo

4,000 RPM
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There is 2 sports mode, one being just normal sports mode, the other is sports sharp which really brings the car alive, giving the raw brutal feel from the previous version STI where there is only 1 mode. Fuel consumption is about 10% lousier even when driving on the normal sports mode, gets much worse when switched to sports sharp.

The different modes vary only the throttle mapping which indirectly affects boost response/delivery.

As for the power delivery to front/rear, it is controlled by Subaru’s DCCD, sort of like the Evo’s SAYC or the Skyline’s Attesa system.
So if I understand you correctly the "sports mode" is just a boost controller + throttle controller. I assume your model its drive by wire already right.

ECU can control CVT ratio? Wow that's new. I never bothered about CVT cause I hate it with a passion.
 

gunnerzz

2,000 RPM
Jul 3, 2014
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So if I understand you correctly the "sports mode" is just a boost controller + throttle controller. I assume your model its drive by wire already right.

ECU can control CVT ratio? Wow that's new. I never bothered about CVT cause I hate it with a passion.
wah..u hated it so much till dont bother abt it. There are different programming too for example on the HRV it will shift to highest ratio as soon as it detect pedal lift of or cruising.It does this much quicker than the CVT on an Iriz. Newbie to CVT might mistaken it with normal autobox.

Not sure abt other make but on the Iriz the engine rev is limited in N.Newbie or haters like u will think its broken...heheheh
 

YellowFlash

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Yes but the difference in performance for my NA cars are barely noticeable so doesn't justify the price difference between the 2 Ron. Maybe I am old uncle already so butt not that sensitive anymore to such marginal difference. If true high performance sports car and turbo cars surely should have much more difference
Yea I guess unless you are going to the track, the difference may not be that noticeable. It may be more noticeable for higher hp cars. M
Nice. You that's a GRF chassis WRX STI isn't it? Since you mentioned 2.5
Yup, that's right, mine is the GRF, the 2.0 would be the GRB.

ECU already controls the CVT, right? Step on the fuel rev goes up, then slowly pick up speed until final ratio. The paddle shifters also changes the CVT ratio....
Just read up and found out that there is no fixed ratio for the CVT as it is just a pulley system and gear ratio can be electronically/artificially controlled. Learnt something new today, haha. I didn't really take note on CVT although one of my previous vehicle was on CVT.

Good article on CVT -> https://practicalmotoring.com.au/car-advice/continuously-variable-transmission-explained/

So if I understand you correctly the "sports mode" is just a boost controller + throttle controller. I assume your model its drive by wire already right.

ECU can control CVT ratio? Wow that's new. I never bothered about CVT cause I hate it with a passion.
Yea, its drive by wire. Only the much older versions were drive by cable and i heard the throttle response is definitely much better by cable.
I think the SI-Drive is more of a throttle controller rather than a boost controller but somehow by altering the throttle mapping, the boost is controlled.

Subaru SI-Drive -> https://www.greencarcongress.com/2006/04/subarus_new_sid.html
 

vr2turbo

Beyond 20,000 RPM!
Helmet Clan
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May 11, 2010
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wah..u hated it so much till dont bother abt it. There are different programming too for example on the HRV it will shift to highest ratio as soon as it detect pedal lift of or cruising.It does this much quicker than the CVT on an Iriz. Newbie to CVT might mistaken it with normal autobox.

Not sure abt other make but on the Iriz the engine rev is limited in N.Newbie or haters like u will think its broken...heheheh
For town driving I actually like the CVT over my old 4 speed auto as 4 speed the ratio too far apart. If 6 speed auto then different story.....hhahhahah
 

RENESIS VIII

7,000 RPM
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Yea, its drive by wire. Only the much older versions were drive by cable and i heard the throttle response is definitely much better by cable.
I think the SI-Drive is more of a throttle controller rather than a boost controller but somehow by altering the throttle mapping, the boost is controlled.

I've heard about this too from people who had driven the latest WRX STI. Local spec 2.5 VAF chassis. Said got delay during throttle input unlike older Impreza like those GDB chassis.
 

YellowFlash

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I've heard about this too from people who had driven the latest WRX STI. Local spec 2.5 VAF chassis. Said got delay during throttle input unlike older Impreza like those GDB chassis.
I think its not that noticeable under normal driving but probably more when you really push the car. After all, today's cars are mostly driven by wire and the response of a STI or any performance cars would already supersede those of normal road cars.
 

^pomen_GTR^

7,000 RPM
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haha...i can't stick to Ron 97 cause there is a high risk of engine knocking, in fact the decrease in performance is pretty obvious once i pump Ron 97. Manufacturer's recommendation is Ron 98 and above, i'd have to de-tune to safely use Ron 97.



I am not driving a SUV, driving a 2.5L turbocharged flat 4 Japanese hatchback :driver:, the premium price for fuel is part of the price to pay for performance...:laugh:

impreza v10 2.5 sti if use lower than it spells ringland! :driver:
 

6UE5t

6,000 RPM
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Oct 8, 2010
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I've heard about this too from people who had driven the latest WRX STI. Local spec 2.5 VAF chassis. Said got delay during throttle input unlike older Impreza like those GDB chassis.
Nothing that you can't fix easily with adding a cheap throttle controller. I also install one on my Mark x.
 

ixeo

4,000 RPM
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wah..u hated it so much till dont bother abt it. There are different programming too for example on the HRV it will shift to highest ratio as soon as it detect pedal lift of or cruising.It does this much quicker than the CVT on an Iriz. Newbie to CVT might mistaken it with normal autobox.

Not sure abt other make but on the Iriz the engine rev is limited in N.Newbie or haters like u will think its broken...heheheh
I don't like the "feel" and "sensation" derived from CVTs. Floor it and it goes to peak torque and it stays there and the engine just drones. My CVT experience limited to the current gen Honda City, Proton Suprima and Proton Inspira.

Automatics like the ZF 8 speed is just godlike, engagement like DSG is exhilarating. I don't understand the need for CVT's existence.
 

Random Post Every 5 Minutes

Engine died many times, uncountable times precisely. Must be the fuckerama idling problem, need to tune.

Another question is, i'm using K&N filter for 1.6/1.8 (but mine is 1.3), will there be any problem? Right after I fix this Air filter, the problem occur.

Before this, my idling isn't that bad, but still fugged up I know. I couldn't start the car easily, have to step on the oil pedal when I turn on the ignition.

Any good workshop to do tuning?
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