1NZFE disappointingly slow; what can be done?

[sergei]

My sister just bought 2005 Vitz RS manual to replace a very ageing AE101 20v.

I thought no "performance vehicle" can be as slow as AE101, I was wrong.
Toyota should be ashamed for creating an "RS" car with such abysmal performance. My estimate of 0-100 is about 11-12s.

In my family we already have couple of 1NZFE powered vehicles, but they are either coupled to Auto or CVT which masks the asthmatic engine.
Well, I think the auto one feels faster (in an IST) than the manual Vitz RS, there is better throttle response, and it revs more freely.
The biggest difference between IST and Vitz is that IST has conventional throttle (vs fly-by-wire). Oh and on that IST I threw away factory snorkel in favour of 63mm pipe (S shape). The factory snorkel starts as 63mm but narrows down to about 30m opening with a tiny trumpet (I guess restriction is for intake noise reduction) . I will probably do that to it first.

So, what can be done to make Vitz RS less asthmatic?

I have driven other Vitz RS manual while looking for a car and all of them were extremely slow.

What would be quarter mile time on those things? I know AE101s do 15s easily.

[Dell'Orto]

A Blitz supercharger kit will wake it up nicely.
/thread

[sergei]

A Blitz supercharger kit will wake it up nicely.
/thread

lol

I have looked into it a while ago for IST, it was a bit pricey and not available.

I will do the usual clean MAF sensor, air filter, reset ECU and see how it feels after that.

[GDII]

2JZ no s*** swap!!

Did I say 2JZ? I meant 2ZZ. Or buy a RUNX Z with the 2ZZ already in it.

[sergei]

2JZ no s*** swap!!

Did I say 2JZ? I meant 2ZZ. Or buy a RUNX Z with the 2ZZ already in it.

Like this?


Why toyota didn't do this? They would sell like hot cakes.

[GDII]

Yes that exactly.

I was looking at possibly getting a Yaris with a 1NZ but glad I didn't. One because lack of power as pointed out by you, two because it is actually too small for what I needed and three that centre dash gauges is just a silly design.

[sergei]

Yes that exactly.

I was looking at possibly getting a Yaris with a 1NZ but glad I didn't. One because lack of power as pointed out by you, two because it is actually too small for what I needed and three that centre dash gauges is just a silly design.

Apart from DOCH Vtec Civics, there is really nothing recent out of the Japan that is exciting.

The centre gauge cluster is easy to get used to (and benefit that you can slap GPS in place of existing cluster without obstructing the view), but lack of power... Actually it is not lack of power but more of really boring power delivery. They could have made it little bit more rev-happy (ie square bore-stroke)...

[Al]

2gr swap.

It's the answer to everything.

[Kiwi-Corolla]

Since it's fly-by-wire, chuck a throttle controller in there. Will make the response a lot better.

[Leon]

The newer Vitz RS's are indeed the most tragically slow car out there.

I had much the some opinion when I drove the ex's Vitz. It has the sporty exhaust and bodykit, and absolutely none of the fast.

The earlier Vitz's with the 1500cc engine are hilarious levels of fun, and fairly sprightly. Later ones it is generally quicker just to walk places.

[sergei]

After doing some reading there are two relatively easy fixes (compared to engine transplants ):

1) Get throttle controller
2) 1ZZFE throttle body with 1NZFE electronics.
3) Sell the car and buy a Civic (not serious option).

I personally would prefer the option 2 as it is transparent from end-user point of view (no mysterious buttons). Not so sure about throttle outlet diameter matching intake manifold inlet...

[RS13]

Agreed, my 1NZ RunX is ridiculously gutless. I've had it with the fly-by-wire throttle as well, after trying everything to get rid of the hesitating off idle its' only marginally better than when I got it 3 years ago. My brother has an Allex with same drivetrain, his isn't much better either.. so I've given up and accepted it for what it is.

The 1NZ-FE has only 80kW and in my RunX with myself and 2/3 fuel load, kerb weight is around 1200kg so can't expect too much performance! Thinking about upgrading to 1.8 Auris or Blade soon anyway so don't mind too much, lol.

[GDII]

I find drive-by-wire an odd sensation compared to the old throttle cable. You feel disconnected from the car at times due to your foot no longer being a direct connection to the engine and in theory the ECU.
Lack of response from low RPM/speed in the Demio but then it's not that powerful and once you hit 3k it picks up well. The one thing I hate about drive-by-wire in a ZRE142 Corolla is the over run from throttle lift when you go to change gears. Normally I would lift the throttle and depress the clutch at the same time and get smooth gear changes but with this version Corolla you have to lift off the throttle a good 1 second before even thinking about depressing the clutch. Otherwise it revs up 500rpm more than where it was when you lifted the throttle due to no load on the engine from the depressed clutch.

The Demio has 66kw @ 6k but isn't too bad a for 1,348cc engine and a 1070kg car. It's got much more torque than the Starlet once the car is moving and driving around town. You actually get minor push back in the seats The Starlet had 48kw new @ 6k but weighed 720kg. It was so slow compared to the Demio even though it had in theory more KW per ton than the Demio. I guess it's down to low down torque and 20 years newer tech.

Starlet 67kw per ton
Demio 62kw per ton

That's an interesting idea changing the throttle body to a 1ZZFE unit.

[sergei]

Just bought these things:

• 1ZZFE drive-by-wire throttle body
• 1NZFE drive-by-wire throttle body

Once both arrive will combine them into a hybrid throttle body that will work with 1NZFE ECU.
The reason why I bough 1NZFE throttle body is so I would not touch original throttle body on the car, as the mod involves removing rivets on the covers and swapping boards.

I wish Toyota would have open ECU like subaru, as actual fix would be changing throttle maps.

[sergei]

Success!

The 1ZZFE throttle body conversion fixed the throttle response and power drop after 5k rpm.

Here is the write up:
http://sergei.nz/toyota-vitz-rs-and-its-disappointing-throttle-response/

[RS13]

Good write up! Incidentally, whereabouts did you source the 1NZ and 1ZZ throttle bodies from and for what cost? In your opinion, is it worth the cost and effort?

[sergei]

Good write up! Incidentally, whereabouts did you source the 1NZ and 1ZZ throttle bodies from and for what cost? In your opinion, is it worth the cost and effort?

Trade me about $100 each.
The 8mm plate is about $50 cut. Also will be 1 hour of my labour just to get tapper into the plate to match 46mm to 56mm.
So total is about $250 and 3 hours of labour.
In hindsight it is cheaper to get Apexi or similar throttle controller.

It will be worth it if I solve random high idle issue. I believe I need to reduce default idle opening with the adjuster screw.

I will report back by the end of the week.

If you ever driven new-ish subaru with SI drive, the difference between 1NZFE and 1ZZFE throttle body on 1NZFE is similar to difference between I-mode and S# mode.

If it was my car, I would have got a custom made alloy manifold with large plenum, with opening to suit the throttle. Since the car is non-turbo and has MAF it should be quiet flexible on the manifold side. The factory plastic job is piss poor and completely kills the induction noise.

[sergei]

Update:

I have got plate cut (~$60), couple of hours filing in the tapper.
I have adjusted the screw on the throttle to fix idle oscillations etc.

All sorted and performs more or less OK.

Here is the detailed write up:

http://sergei.nz/toyota-vitz-rs-throttl ... -out-bugs/