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Discussion Starter #1
Hi, I have a 5d 1.8 sport. (FK2)
Is there anyone who can tell me what happens at 5500 rpm.

Sometimes during acceleration, the car pulls noticeably stronger when it reaches 5500 rpm.
 

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Tarmacadam Terror
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that will be the vtec system engaging lol, switching cam profiles
 

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Tarmacadam Terror
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Think it depends on throttle position


"Powered by dinosaur bones"
 

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Tarmacadam Terror
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Lol my vtec comes in at 4400rpm, slightly different engine though ;)


"Powered by dinosaur bones"
 

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My VTEC doesn't VTEC
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Lol, just a bit seeing as we don't have proper VTEC, I describe it as switching from the eco cams to the **** cams ;)
 

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What he say's ;)

The 1.8 does not have true vtec, i.e it does not switch into a performance mode, what you feel is it coming out of an eco cam profile into a 'normal'

From the WIKI

The VTEC mechanism changes the valve lift and timing by using more than one cam profile.
The 1.8 uses the VTEC system totally differently to the Type R - it has a normal cam lobe which is used nearly all the time. So when you are accelerating, it uses the normal one all the time, and there is no "extra performance" kick. Just like a normal engine.
But under very light "cruising" (just a touch of throttle and less than 3500 rpm), the engine uses the VTEC system to switch cams to cause the inlet valve to close very late. At the same time it re-adjusts the throttle butterfly to a wide open position. This reducing pumping losses. It's an economy thing.
When the VTEC system jumps cams and opens the throttle, you can sometimes feel it as a slight stutter, or hesitation. Many owners complain about this, but it's the price paid for economy on the 1.8. Software updates may reduce the effect, but probably never get rid of it (since there is such a big change in the way the engine is working, and it takes time to make the change).
More info here:

VTEC - Civinfo Wiki

The stutter has been eliminated on the R18z1 engine used in the 9Gs I assume by means of a software update.
 

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Tarmacadam Terror
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Lol dude want high cam gots to have a k20 ;)


"Powered by dinosaur bones"
 

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Tarmacadam Terror
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the r18 is a great engine, streets ahead of any of its NA rivals imho
 

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Type EX,A guy called Mark
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You guys are wrong the 1.8 does have true VTEC.

VTEC (Variable Valve Timing and Lift Electronic Control) is a valve train system developed by Honda to improve the volumetric efficiency of a four strock engineThe VTEC system uses two camshaft profiles and hydraulically selects between profiles. It was invented by Honda engineer Ikuo Kajitani,and was the first system of its kind.

I have never read anywhere that it states that only Type R has VTEC.
 

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the r18 is a great engine, streets ahead of any of its NA rivals imho
Excatly :like:

Some will slate it on here because it's not as quick or performance orientated as a K20... Some can't even see past the fact Honda make Civics other than the CTR.

But, compared to other similar engines in it's class, it very good and has very good performance for an 'Ordinary' family car.

Drive a 2.0 Focus or Astra... Nice cars, comfortable, quiet, but it terms of performance and putting a smile on your face... the 1.8 R18xx is much better.
 

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You guys are wrong the 1.8 does have true VTEC.

VTEC (Variable Valve Timing and Lift Electronic Control) is a Valvetrain - Wikipedia, the free encyclopedia system developed by Honda - Wikipedia, the free encyclopedia to improve the volumetric efficiency of a four-stroke Internal combustion engine - Wikipedia, the free encyclopedia. The VTEC system uses two camshaft profiles and hydraulically selects between profiles. It was invented by Honda engineer Ikuo Kajitani,[1][2] and was the first system of its kind.

I have never read anywhere that it states that only Type R has VTEC.
The critical thing is that the cam profile is totally different. The 1.8 merely goes from an economy one to a more normal one with slightly more lift and duration but nothing compared to the R.

Without looking at the R18 figures in detail id imagine you would be in the vicinity of where max power is produced which could be why you see this as a sweet spot.
 

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You guys are wrong the 1.8 does have true VTEC.

VTEC (Variable Valve Timing and Lift Electronic Control) is a valve train system developed by Honda to improve the volumetric efficiency of a four strock engineThe VTEC system uses two camshaft profiles and hydraulically selects between profiles. It was invented by Honda engineer Ikuo Kajitani,and was the first system of its kind.

I have never read anywhere that it states that only Type R has VTEC.
True... Good point, it just works in a different way.
 

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My VTEC doesn't VTEC
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I did say "proper vtec" as in the vtec everyone talks about when discussing Hondas, I know the 1.8 has two cam profiles just its not as pronounced as the type r
 

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The critical thing is that the cam profile is totally different. The 1.8 merely goes from an economy one to a more normal one with slightly more lift and duration but nothing compared to the R.

Without looking at the R18 figures in detail id imagine you would be in the vicinity of where max power is produced which could be why you see this as a sweet spot.
The change can come at different points... baisicaly when there is reduced load on the engine i.e cruising or driving like a granny, it will go into eco mode.

Boot it, and it will switch to normal... it is however more noticeable in the 8g over 4k rev's
 

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The change can come at different points... baisicaly when there is reduced load on the engine i.e cruising or driving like a granny, it will go into eco mode.

Boot it, and it will switch to normal... it is however more noticeable in the 8g over 4k rev's
Yes I left out the throttle position part just making the example, it is a clever system, and the 1.8 is no slouch.

4K and above is where most N/A engines come into their own anyway with max torque and power being hit and also very linear delivery.

Wonder what the R18 would produce if allowed to rev to 8300?
 
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