What is the difference between the base and the GT engine?

1.8-liter VVTL-i (2ZZ-GE) and VVT-i (1ZZ-FE) engine, transmission, exhaust, intake, and performance tuning discussions
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ebslopp
Posts: 676
Joined: Thu Feb 19, 2004 5:22 am

What is the difference between the base and the GT engine?

Post by ebslopp »

I was just curious, since they are both the same size and both have variable timing. What did they do to the GT to boost the HP like 50?! Is there a way that I can turn my engine into a GT engine by swapping a few parts, or would I be better off to drop a GT engine into it?
--------------------------------------------------------------------------------2004 Base - TwoTone Neptune - 5 speed There are 10 types of people in life. There are those who understand binary and those who do not.
ragingfish
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Re: What is the difference between the base and the GT engine? (ebslopp)

Post by ragingfish »

First off, why not buy a GT if you wanted a GT?Anyway, two major differences. Compression and lift.Compression of base engine is 10:1, while GT is 11.5:1.GT's higher CR requires premium fuel.GT also has Lift. Quote, originally posted by http://www.newcelica.org/other/faq/vvtl-i/vvtl-i.htm »VVTL-i einges also have a second set of cam profiles on each cam to give you the "race car when you want" it approach. Tach it up to 6 grand and the motor turns into a monster. The motor puts out a scream as it warps into hyper drive! It feels like a race turbo kicking in with all the added horsepower and torque in a matter of a few hundred rpms. Lift uses oil pressure to push a pin under the rocker arms and cams to force the motor to use the bigger profiles that are not used under normal driving.Converting a base engine to a GT engine would proably cost more than just dropping in a GT engine.
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AKLGT
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Re: What is the difference between the base and the GT engine? (ragingfish)

Post by AKLGT »

or just buy a s/c!
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Mavrik
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Re: What is the difference between the base and the GT engine? (trdvibe)

Post by Mavrik »

Quote, originally posted by trdvibe »or just buy a s/c!Hope beat me to it. The base engine is compatible with a Supercharger which will pretty much even the odds. Lift is always there at low end were as the GT has lift at the high rpm end. Sadly though the Vibe base auto is the only one with the supercharger... Sometime soon... or so it will be available on the base Vibe 5spd.
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NovaResource2
Posts: 146
Joined: Mon Jan 19, 2004 8:18 am

Re: What is the difference between the base and the GT engine? (ebslopp)

Post by NovaResource2 »

While both engines are 1.8L, they are not the same. The GT engine has a larger bore and a shorter stroke compared to the base engine. No, you can't "bolt on" parts to your bas engien to make it a GT. The only way to get a GT engine is to install one (or trade in your base and buy a Vibe GT). Like other have said, installing a supercharger will give your base the performance of a GT.
NovaResource2
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Re: What is the difference between the base and the GT engine? (Mavrik)

Post by NovaResource2 »

Quote, originally posted by Mavrik »Lift is always there at low end were as the GT has lift at the high rpm end.Incorrect. The base engine does not have lift. Both engines have Variable Valve Timing at the low end but only the GT has Lift. That's the difference between VVT-i (base) and VVTL-i (GT).
scherry2
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Re: What is the difference between the base and the GT engine? (ragingfish)

Post by scherry2 »

Quote, originally posted by ragingfish »First off, why not buy a GT if you wanted a GT?probably wanted the auto trans.
HIGHREV2
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Re: What is the difference between the base and the GT engine? (scherry2)

Post by HIGHREV2 »

The other difference people neglect to mention with the base vs GT is the transmission. I am convinced that the tight gear spread in my 6sp alows me to exploit the rpm range more. I would like to see some race comparisons between the GT and a S/C 5sp. Not just straight line performance, you know curves and stuff are more common that dragstrips. People say the GT is hard to keep above 6K, The only time I feel that is an issue is the 1st-2nd shift. Othe than tha if I hab=ve the room it stays above the6K mark when I want speed.MatrixVibeNet has some cool tech info on the engines. The technology in the 2ZZ engine is wild. Composite block & liners, laser cut valve seats, etc. They also go into how they made the choices in building the engines.
HIGHREV2
Posts: 16
Joined: Wed Dec 31, 2003 9:41 am

Re: What is the difference between the base and the GT engine? (HIGHREV2)

Post by HIGHREV2 »

Quote, originally posted by HIGHREV2 ». Othe than tha if I hab=ve the room it stays above the6K mark when I want speed..Wow, Too much coffee. I should pay more attention when typing
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