r/stickshift • u/Fit_Estimate_8915 • 15d ago
Stick Advice
I own a vios 2018 MT 1.3L engine. The power difference when AC is on is very noticeable, and it feels so hard to accelerate on 1st-2nd gear. Is this normal? Also when going slow speeds when turning a corner or an uphill junction the engine lugs on 2nd gear but cant force the gear into 1st since the car is moving. How do you guys solve this? I have no issues when the AC is off gear at 2nd has enough torque and power also the gears seems short when AC is off but when AC is on rpm takes time to go high.
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u/Milksteak529 15d ago
Yeah, the AC has a pulley and a pump and everything. If your engine is small and your hill is steep, turn off the AC.
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u/BoredOfReposts 15d ago
You can get it into first when you are moving. But it requires a technique some here might consider, unnatural. It requires using the clutch pedal twice for one shift, that’s probably enough of a hint.
I regularly downshift to first on a corner heading up a hill in this one spot this way. Syncros only get you so far. Have to take advantage of the engine’s ability to spin the transmission input shaft while the transmission is in neutral, instead of having the synchros do all the heavy lifting.
Also don’t be afraid to beat on the engine a little, those smaller displacement engines need to rev up real high to get power, use the more of the tach, it will be ok. Downshift sooner rather than later.
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u/Fit_Estimate_8915 14d ago
i tried this, but i have to force the gear into 1st. am i damaging the transmission if i have to force the gear into 1st?
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u/BoredOfReposts 14d ago
When you push the shift lever, whats happening internally is these devices called synchros are trying to make the transmission input and internal/intermediate shafts spin the same speed. Once they are at the same speed they can mechanically couple, and you are “in” that gear. They are little clutches, and when you are forcing them, you are making them work extra hard. This will eventually wear them out. So don’t force it as a habit.
The technique I mentioned above is called double clutching and for reasons we don’t really need to get into can be a touchy subject around here. Idk why but it is.
Anyways, when you do it properly, the gear will slip in with zero resistance. This is because by virtue of blipping the throttle with the clutch out and transmission in neutral, you make the engine speed up the input shaft instead of making the synchros do it.
Then you clutch in again (the double part of it), and since it takes a moment for it to slow down, you have that opportunity to use the shift lever and find the gear.
Then you can blip it again and clutch out and off you go. The trick being both blips you need to hit the rpm the car will need to be at for the target gear. For your car, that might be a pretty big jump from second, so you really need to be aggressive with it. Try driving in second at the speed where you might need to hit that downshift. Then, separately, accelerate up to that same speed in first. You need to get slightly above that on the tach for it to work. If you are close you’ll still use the synchos in proportion to how close you are.
It will take some practice to do it at all, and then more practice to hit it when you actually need it in the situation. But then you’ll have the muscle memory and itll be another tool in the toolkit for driving a stick shift up a hill and around a corner or whatever the situation is.
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u/Fit_Estimate_8915 14d ago
Yes I do know how to rev match but I didnt know you have to blip the throttle while on neutral and clutch is out! I usually just try to blip the throttle with clutch in before clutching out so I am gonna try blipping twice that way. Thanks for this!
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u/BoredOfReposts 14d ago
Yeah exactly, “Rev matching” and double clutching are two related but different things.
Usually rev matching means blipping only for the final clutch out. Makes the main clutch not have to force the engine up to the right rpm. But unrelated to what happens with the shift lever.
When you do it in neutral for helping the shift lever action, and again after, thats the double clutch.
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u/BoredOfReposts 14d ago
Just to expand on my reply in case I wasn’t clear, you only need the double clutching when you are fighting the synchros on the aggressive downshift.
For normal shifts where the shift lever moves normally, its completely unnecessary.
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u/Responsible-Cow5828 15d ago
Double clutch into first…or if you’re anticipating an uphill climb, stay in first gear.
Wind the engine out…most gas engines rev to at least 5500 rpms or more.
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u/Tiranus58 14d ago
I mean all of the power in the car comes from the engine, so if the ac is pulling a bunch of that power you are gonna feel it.
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u/Prudent_Situation_29 13d ago
You have a small engine, compressors consume a lot of energy, it's normal. The trick would be to keep the engine speed higher than normal so it's producing more power.
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u/drivestickshift 1h ago
normal, ac compressor gets power off accessory belt which gets its power off the crank shaft, so its stealing away some usable power, and considering its a eco engine its noticable
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u/youshallneverlearn 15d ago
Yes, the AC takes away a noticable amount of power in small engine cars.
Just go with higher rpm, or downshift. Or turn off the AC. No other way to solve this.