MR2 Roadster Owners Club

The Workshop => Performance Related => Topic started by: inside on April 28, 2016, 17:24

Title: Stock 2zz engine response
Post by: inside on April 28, 2016, 17:24
Hi guys,

I'm just starting on the 2zz swap route (donor car on the way) and I've been thinking about engine responsiveness. One thing I really dislike with 1zz is that it is kinda laggy and slow to pick up revs in neutral, quite the opposite of what a nice 4-banger should be.

So how is the 2zz engine response in comparison to 1zz? Some say it is similar to 1zz upto 6000 rpm, although this doesn't say much about response.

Does it pay to replace flywheel or maybe machine a stock one? I'm not a fan of either option and would ideally stay stock.


Cheers
Uros
Title: Re: Stock 2zz engine response
Post by: Alex Knight on April 28, 2016, 18:03
Throttle response is obviously different to pickup.

In terms of response, it's fairly typical 4-cylnder Japanese fare to be honest. Similar to a Honda B and K-Series.

Don't let anybody tell you that the 2ZZ is the same as the 1ZZ to 6,000RPM. It's not. There's more torque (area under the curve) everywhere below 6K, and significantly more above 6K (obviously).

The gearing is also quite different, utilising shorter ratios and a shorter final drive, which undoubtedly contributes.

With regards to the flywheel, I personally am going to replace the stock flywheel with a lightweight flywheel when I replace the clutch. I've driven a 2ZZ MR2 with a lighter flywheel, and I believe it's worth the cost.

I've had excellent experiences with Fidanza flywheels in the past, very high quality, and a "fit and forget" item.

Here's the white paper on the 2ZZ-GE engine. It may be of interest to you: 2ZZ-GE (http://www.chriswilson.tv/2ZZ.pdf)
Title: Re: Stock 2zz engine response
Post by: inside on April 28, 2016, 18:46
Cheers Alex. So would you say response is significantly better than 1zz, or no difference at all?
Title: Re: Stock 2zz engine response
Post by: TiM3 on April 28, 2016, 22:06
I also like engines that zip up and down the revs when you blip the throttle, not sure why, I thinks it's because I had quite a few bikes when I was younger.

The 1zz does feel quite lazy in that respect, I have a 2zz with a TTE lightweight flywheel and I would highly recommend it!
Title: Re: Stock 2zz engine response
Post by: J03 on April 28, 2016, 22:20
They might share the same displacement, but one is a mass produced eco engine, the other, a Yamaha screamer  s:D :D s:D
Title: Re: Stock 2zz engine response
Post by: JoeCool on April 29, 2016, 00:17
Fidanza flywheel.

That's all you need.

Absolutely zero detriment to day to day driveability (I've stalled it 4 times total) and it just makes ththrottle response/gear change/driveability a dream.

I'm honestly not lying when I say it's then best £250 I've spent on a car ever.

Idle is fine, pulling away is fine, heel 'n' toes is awesome! Just do it if you're doing the swap. It's the flywheel the 2zz needs.
Title: Re: Stock 2zz engine response
Post by: Alex Knight on April 29, 2016, 09:10
Quote from: "inside"Cheers Alex. So would you say response is significantly better than 1zz, or no difference at all?

It's been so long since I drove a 1ZZ, I honestly can't remember!
Title: Re: Stock 2zz engine response
Post by: inside on April 29, 2016, 21:42
So I got the donor celica today, and managed to take it for a quick spin. It felt night & day difference compared to 1zz in terms of response and liveliness. I think stock flywheel will do for me. Great engine, I know now what you meant saying it screams...  s:D :D s:D  Can't wait  s:) :) s:)