2AZ-FE ENGINE DEATAILS

[JohnBrowning]

For complete article see SAE 2001-01-0327

Chain Drive DOHC
4 Valves per cylinder
Stainless steel tubular exhaust mainfold
Variable intake valve timeing 50 degrees
Resin ballance shaft gear drive
Resin intake manifold

Variable exhast tuning ( has a valve to tune exhaust system)

central cooling in head run verticly from cylinder 1-4
Inclined squish with angled pent roof design
12 orfice fuel injectors
Reduced valve train weight to decrease spring load

Low tension piston rings with single 2mm wide oil ring

Resin coated piston
Forged steel crank
Smaller mains
micro grove bearings
Compact ballance shaft
Magnessium valve cover
Light weight oil pump with intergral pickup screen

Improved warm up charteristics trhough small water jacket depth in the cylinder block.

Aluminum die cast block
Water pump houseing intergral to block.
NVH inprovement
Enhanced transmission rigidity
elimanation of mounting brackets for accesories

Torrsional damper to protect the resin gears on ballance shaft from torque loading.

Conclusion

1) Higher output and flat torque curve.
2)Better fuel consumption.
3)Meet LEV regulations.
4)Good sound quality (NVH).
5)17% lighter then previous model abd more compact with an increas in displacement.
6) Resin gear drive ballance system.

 

[Ken4]

Here are some pics to accompany your detailed description. Enjoy!

goes 15,000km or 12months with any SJ, SL oil!

 

[JohnBrowning]

Ken is the driver seat on the right hand side of that car???? I noticed that the master cylinder is on the oposite side of the car.

What oil are you running? What have your UOA shown? Does this engine settle down nicely or does it throw alot of wear metal?

Do you have a hard time keeping the RPM's below 4000. This engine is so quite that all I can hear is wind noise and tire noise. If not for the tach. I would be clueless. The torque curve is so flat that you can not go by power fall off to know when to shift. I have 540 miles on it and have hit 6000 RPM's a few (twice) times. I hate to go that high on a new engine. I never hit the rev limiter so I have no clue where that is. It must be some place between 6500 and 8000 as that is wear the redline begins and ends on mine.

So far I really like this car. I never thought I would ever get excited about a little 4 cylinder but this engine is sweet!! This engine begs to be turbo charged.

 

[Greaser]

quote:

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Originally posted by Steve S:
IMO to much plastic !!!!! Toyota has a sludge motor with plastic parts? Plastic worries me to no end. It just might work.

---

Ditto dude..

 

[Amkeer]

What plastic are you two refering to? I am curious.


Daily Drives
-2003 Toyota Tacoma PreRunner XtraCab, Impulse Red, Peppy 2.7 Liter 4 Banger, Running Mobil1 Synthetics SS 5W-30.
ODO 3400 Miles.
-1995 Toyota 4-Runner, Evergreen, 3.0 V6, Running Mobil1 Synthetic SS 10W-30.
ODO 76000 Miles.

 

[Ken4]

Amkeer, Resin = Plastic.

John, yes it is a RHD made in japan model. Did my first UOA here:

http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=3;t=000387#000000

Presently using Castrol RS 10w50. Never had a chance to go beyond 4000rpm, Im still breaking it in gingerly. I find it noisier than the previous outgoing 2.2L 5S-FE, possibly due to the timing chain that gives it an annoying whine. Fuel economy also seems to be worse than the previous model

. But it is a larger engine.

 

[Terry]

Thanks for the pix Ken. I like it ! I like chains instead of timing belts !

John do you know if timing chain is a moly alloy similar to Nissans very quiet design ?

 

[Steve S]

IMO to much plastic !!!!! Toyota has a sludge motor with plastic parts? Plastic worries me to no end. It just might work.

[ June 29, 2003, 12:12 PM: Message edited by: Steve S ]

 

[Shannow]

If you ever get a chance to read Sir Harry Ricardo's book "The high speed internal combustion engine".

An appendix at the back has a mid 20s Vauxhaul race engine. DOHC, 4 valves per cylinder, pentroof chamber, cams driven from between cylinders 2 and 3 to reduce flex, half water jackets (top half of bore only cooled - quicker warm-up, and more even cylinder temps).

It's a blast to read what they had 80 years ago, and see where modern technology has gotten us.

(It's all materials science and electronics - the ideas have been around for nearly 100 years)

 

[Amkeer]

Thanks Ken! I have been sleep deprived the past 6 weeks due to my newborn so that one wizzed right over my head.

 

[JohnBrowning]

Terry I do not know. I saw some mention of the chain on another site. My article does not mention it. I remember an Austrailian site mentioning somthing about the chain. I seem to remember that it is a single not double roller chain. Sorry! If I find out more I will post more. I am suprised to see any reponce to it.

I found one thing strange! It uses shimless cam buckets? I sure hope it has mechanicly adjustable followers like the older designs! The VVT-i system is amazeing. The torgue curve is almost completely flat from 1000-6000 RPM's.

 

[Terry]

Thanks John. Is this the same engine in the Echo or a new one ? Kind of a world market engine ? Lots of coatings used I see.

I know one thing Ken 4's engines are clean inside and out as he is a valued customer ! Hey you Canadians quit whining about sending oil samples down here, Ken sends them from Singapore to Greenville, Texas with no issues.

 

[JohnBrowning]

Terry, THe 2AZ-FE is only used in the Camry and Highlander as base engines in the U.S. It is a world engine though. They also have a direct injection model in 2.0L size.

Yes their is alot of resin. The gears are attached to steel ballance shafts useing rubber elastomer dampers to protect the resin gears from shock loading. The resin is propietary and reenforced with armid fibers. It's hot fatigue strength was 20 (Mpa) greater then phenoplast at 130Cx10-8th. The bending strength was 100(Mpa)greater at 0 degrees and about 20(Mpa) times greater at 200C then phenoplast. I would rather have steel gears but I have to take it how they make it. I can rember Chevy and Dodge or Ford I think playing around with glass reinforced nylon timeing gears. The after market decided to offer a steel replacement in additon to the nylon/glass ones.

We will soon see how this engine holds up. I will be sending a sample off as soon as I change it again. My driveing style is rather agressive. I did a agressive breaking for first 58 miles and drained out factory fill. I left the OEM filter in place. I refilled it and will be changeing soon. I have tried to keep it under 4000 rpm's but I have hit 6000 RPM's at least twice by accident. The engine is so smooth and quite I had no idea I was that high in the rpm band until I looked at the tach.

My driveing is almost all high speed driveing with frequent accleration pass's to pass slow moveing traffic on secondary HWY. This should contrast with Ken's driveing style.

Terry Kens engine does not have EGR system to contend with! Could this be one reason his is so clean!!!

 

[Terry]

No EGR is a big plus !

Ken likes to romp from stop light to stop light so it will be an interesting comparison. The quality of the RS Castrol product is impressive and looks alot like a very good friends formulation developed over here in US. I have been less impressed with the RDS oils he has run since.

Of course no one in this industry borrows chemistry , would they ? HA !

Thanks alot for the in depth on the construct of the engine. Knowing Toyota they did it right.

 

[Ken4]

But unfortunately the new 2AZ-FE has got VVT, which means the closing of the exhaust valves overlaps the opening of the intake valves....meaning some of the exhaust gases are recirculated back into the cylinder at the same time the new fuel/air mix is injected which is similar to the principle of EGR.

 

[JohnBrowning]

Ken4 excellent point. You must be a car guy. The only way to truly get that internal egr effect on a streetable car is with VVT-I. It mainly funtions at low-medium loads. You really have to have you your intake pulses and exhaust pulses tuned very tightly. It is all about the intake inerita and overlap!!! You couple that with 2-3 three way converters and tight fuel controls and you get NLEV/ULEV certified engine. My engine is certified for both. This is one of the reason so many companys are bringing out variable valve timeing. Sure increased HP and broader power band are nice tools for marketing to play with but it is mostly about future emissions and C.A.F.E.!!