What is 1zz and 2zz

[ride22]

I always see 1zz and 2zz engines. What does this mean, and which does the GT-S have?

[2kgtx]

The 1zz-fe is the GT engine and the 2zz-ge is the GT-S engine or is it ge is the GT and Fe is the GT-S anyway 1zz is the GT and 2zz is the GT-S

[scapamouche]

The 1zz is a couple years older than the 2zz. It's been used on Corollas before, I think.

It's in Corollas, Matrices, Celica GTs and MR Spyders these days.

The 2zz is a redesign of the engine with high rpm power in mind. It has a larger bore and shorter stroke (wider pistons that move a shorter distance vertically) to achieve the same displacement (2cc off, anyway.) It uses a Lift pattern on the intake cam very similar to VTEC to make high end power. It also has VERY high compression: 11.5:1. By way of example, you don't want to run more than about 10.0:1 on a carburated engine, using pump as (92 octane) because of detonantion concerns.

The 2zz only appears in the Celica GT-S, Matrix XRS and Vibe GT

The 2zz is a VERY peaky engine that makes LOTS of high end power at the expense of low end performance and torque.

Any more you want to know? Ask, or look at the FAQ on the home page. I think there's some more useful info there.

[2kgtx]

Originally posted by scapamouche
The 1zz is a couple years older than the 2zz. It's been used on Corollas before, I think.

It's in Corollas, Matrices, Celica GTs and MR Spyders these days.

The 2zz is a redesign of the engine with high rpm power in mind. It has a larger bore and shorter stroke (wider pistons that move a shorter distance vertically) to achieve the same displacement (2cc off, anyway.) It uses a Lift pattern on the intake cam very similar to VTEC to make high end power. It also has VERY high compression: 11.5:1. By way of example, you don't want to run more than about 10.0:1 on a carburated engine, using pump as (92 octane) because of detonantion concerns.

The 2zz only appears in the Celica GT-S, Matrix XRS and Vibe GT

The 2zz is a VERY peaky engine that makes LOTS of high end power at the expense of low end performance and torque.

Any more you want to know? Ask, or look at the FAQ on the home page. I think there's some more useful info there.

:eek: Wow you know your sh!t,

[ride22]

Thanks for the info!

[Da Kine Guy]

Actually, the Lift occurs on both the intake AND exhaust valves, it is the variable valve timing (VVT) which only occurs on the intake valves.
http://www.greganti.com/celica/specifications/valvetrain.jpg
Here you can see the VVT controller (oil pressure controlled screw type mechanism which advances or retards the ignition timing continuously) on only the intake valve. Here it is up close:

http://autozine.kyul.net/technical_school/engine/vanos.jpg

You can also see the two different cams (in the first picture) for each rocker arm, the smaller being the low RPM cam and the larger the high RPM cam. If anyone wants to know how lift works just ask and I will try to explain it in another post.

[HisFrogness]

I thought I read somewhere that the 2zz has a LONGER stroke than the 1zz.

[Da Kine Guy]

Originally posted by HisFrogness
I thought I read somewhere that the 2zz has a LONGER stroke than the 1zz.

Nope, shorter stroke, bigger bore. A shorter stroke is more ideal for high-reving applications because there is less piston travel.

[GTS LAID]

Originally posted by Da Kine Guy


Nope, shorter stroke, bigger bore. A shorter stroke is more ideal for high-reving applications because there is less piston travel.

Yup Yup Yup... remember it has to maintain the same overall volume (to 3cc) which means if its a longer cylinder it would have to have a smaller cross section (bore).

[ride22]

Couldn't have asked for better responses. Thanks eveyone!

[scapamouche]

That stroke vs bore thing confused the heck out of me, too, at first. Some of the literature out there seems to have misquoted the bore and stroke of the two engines.

I wasn't aware that lift affected the exhaust as well. i thought it was only intake. AS they say, a picture is worth lots o words. Thanks, Kine.