AE101 with SUPERSTRUT Suspension
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AE101 with SUPERSTRUT Suspension |
The later Corolla LEVIN Apex GT's are almost unknown amongst the range of used imports that have come into Australia from Japan over the past few years. . . . . Few people had any idea what my 101 was, and I could find very little on the web myself. I have put this page together as a reference for people who would like to know more about the AE101 and AE111 Apex GT's.
Main Features 5 valve, 4 throttle body,10.5 C/R, Variable Valve Timing System with factory precision balanced internals and tuned length 4 into1's giving 160+ hp@ 7,400 RPM. ABS, 2 pot discs and 15inch rims - all part of the "Super Strut" option that this car came with.
The Engine is Toyota's highly regarded, Cosworth inspired
4A-GE, for which Yamaha designed the 20v head. The features of the APEX Engine
are its 5 valves per cylinder, Variable Valve Timing, individual throttle
bodies, 4 branch exhaust manifold, 10.5.1 compression ratio and a lightened
bottom end compared to a normal 4A-GE. The rev limiter cuts in at 8,400rpm.
Toyota quote these engines at 160hp, with the "blacktop" AE111 at
165hp. The blacktop develops more hp thanks to its impressive 11/1 compression
ratio, even further lightened reciprocating mass ( conrods in particular) and
more efficient throttle bodies.
There is a weakness with the
electronic VVT on these engines however, not shared by the
silvertop motor. The Blacktop uses a variable control for valve timing while
the silvertop has an "off" "on" mode only. The blacktop
electronic controller unit gets more of a workout and subsequently one of the
transistors can readily overheat and literally burn out. The damage is very
visible when the circuit board is removed from its housing. If you are running
a blacktop with no bottom end this is where your problem is, it is quite
common.
Yamaha have had a long history of involvement with Toyota on cylinder head
development since the ground breaking Toyota 2000GT of the mid 60's. The three
tuning forks symbol can be seen on the head castings of some of the premium
performance Toyota engines since those days.The roots of the five valve design have their origin
with Yamaha's involvement in Formula 1 engine design and manufacturing in the
late 1980's through to the Mid 1990's. Yamaha quickly settled on a five valve
head layout as the optimum design for power production for the normally
aspirated engine.
Yamaha's five-valve cylinder head design enhances engine performance in two ways. The three small intake valves offer more effective intake area than two similarly placed larger valves. The result is greater intake efficiency allowing for higher peak power and broad torque band. The reduced reciprocating valve mass or weight allows high revs without valve float. Yamaha's application of five valves has resulted in a shallow combustion chamber that permits high compression ratios without the destructive effects of detonation and to provide both low-end torque and great top-end power. Yamaha used the 5 valve design on some of its four stroke motorcycles of the era such as the FZR750 and ? various snowmobiles. AUDI developed its 5 valve, four cylinder range of 2 litre to 1.6 litre engines in the early 90's - possibly influenced by Yamaha's commercial success with this format. They continue in production today, in normaly aspirated and turbo versions knocking out up to 200hp.
Compare an AE101Apex GT with a contemporary 1600cc sports vehicle, such as the latest Mini Cooper (released in Feb 2007). You can see what an outstanding vehicle the Levin really is when you carry out a comparison of the engine output and capabilities of the two. The new Cooper develops 111hp at 6,000rpm - the rev limiter cuts in shortly after, at around 6,400rpm. Meanwhile, the Levin is pulling strongly away as it reaches peak power at 7,400rpm (160hp) running 8,400rpm before the limiter cuts in.. . . . . . The power difference is massive.
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Toyota recommend 100 Octane for the 20 Valve Engine. Unlike a lot of cars manufactured in the past 20 years, the ignition timing is easily adjusted. Retarding the timing a couple of degrees, the car runs perfectly on more easily obtainable 98 Octane fuel.
Running standard factory timing of 10degs BTDC, you will still occasionally experience a healthy crack of pre ignition on the 98 Octane - usually moving off from standstill on a hot day -just to remind you you are driving something a little more highly strung than a Ford Falcon.
Toyota's Superstrut Suspension option. While the name is enigmatic, in practical terms this is a variation of a double wishbone suspension. Superstrut was an option on a small number of sport Toyota models of the same period. While I am somewhat unsure of the exact additional engineering, the resulting vehicle handling is absolutely stunning. The ride is quite firm but not uncomfortable or tiring. It is a very well developed set up - spring rates and shock absorber settings are spot on, with just enough give and controlled dampening so the ride is never bouncy or jarring. I prefer cars with firm suspension, particularly when they have such a well sorted rigid chassis. The Superstrut option includes a very serious brake upgrade to big diameter discs, twin piston front callipers, ABS and 15 inch rims. Link here for a great description of Superstrut. . . . NZ GT Fours Page
A Levin is a great driving experience. It's rather like driving a sprint car - the superstrut has this massive ability to go round corners at speed almost without any effort, the steering feels as direct as a go kart and the engine just wants to soar straight to 8,000rpm plus. . . Its very frustrating driving in suburban traffic - you just want it all to melt away and morph into an empty racetack . . . . . The close ratio gearbox is as brilliant as the engine, with its short throw and light and precise action. The brakes feel like they would stop a truck - they are massive for a car of this weight. The car really comes together in tight challenging cornering with the needle pointing past 7,000 RPM. Then you can feel the full benefit of the great handling, braking and power. It also makes a great cruiser, these 20 valve engines are extremely fuel efficient, seats comfortable with plenty of travel, and the split fold down rear seating makes carting large objects or lots of luggage no problem.
These two are fitted with the C56 5 speed box - that came with the later 101 levins and ran in the 111 for 2 or 3 years before it was replaced with the 6 speed.
The C56 is a fine gearbox without any particular vice - they are slightly more efficient than the 6 speed in respect to energy absorpbtion, Despite having one less gear, I have the satisfaction of knowing that more of my horses are getting through churning the 2.6 litres of GL4 90W gear oil to warm my CV joints.
Speaking of gear oil, I have mixed Castrol VMX-M multigrade transaxle oil 50/50 with
a 90W oil for the 111 gearbox. The VMX-M is a GL4 oil of 70/85 viscosity so the
net result is a subtle thinning of the gearbox lubricant. .. . . resulting in a
far nicer gear shift especially when the car is cold. There are some expensive
synthetic multigrade gear oils out there but I am pleased with this relatively cheap
solution - cheap is actually $0 as I had the oil already. . . . Normal owners
would probably choose to use the multigrade synthetic transaxle goo at about
$25 a litre. If your Levin has a harsh shift, its probably been filled with a
straight 90 GLUG during a service by some cut price service chain - drain
it and replace it with a multigrade 75-90W API GL4/GL5.
Levin BZ-G has a 70Kg weight advantage over a 101 Levin
The fact that an engine in this state of tune can be used at all in everyday driving is really a celebration of variable valve timing, and black box electronics. In fact to drive the Levin in traffic is not too much different than your mum's SECA - not quite the same, but amazing that Toyota have managed this engine so well that it can operate all the way from 1,800rpm to 8,500rpm. One thing. . . . I need to hear it running or I can easily stall it on take off in stop start traffic, this applies to both Levins. It does require some careful clutch use on take offs. I prefer to let it run in third if I'm sitting around the speed limit in town - it feels happier spinning at 3,000 - 3,5000rpm than 2,400 in fourth. . ., though it will do it with no complaints.. . . It will even pull cleanly from around 2,000rpm in fourth if you have to give it a bootfull . . . I don't like doing it though. The electronic control on the VVT system does suffer overheat failure on the "Blacktops". A single transistor fries - its very obvious when the circuit board is inspected - the transistor in question is clearly visible . . . If your Blacktop has no bottom end, have a look at the control unit - it's behind the radio.
I have been driving the Black Top BZ-G as my everyday car and it strikes me as having a little more torque than a silvertop right across the range and definitly stronger at the top end- sounds much the same. I have been told in competitive circuit driving with equal skill levels, a blacktop will end up a full cars length ahead of a silvertop on performance advantage.
A lot has been made about the differences between the two, but for me so far it has been very subtle. The Black top never suffers from pre ignition or pinging while the silver top is easily prevoked - The 101 runs at its best with the ignition timing advanced just to the point of knocking , anything less and it feels somewhat flat- the 111 has plenty of power and I haven't touched the timing. If your looking for maximum output for your silvertop - try short velocity stacks for a 7 hp gain.
Toyota ceased production of the Silvertop motor in 1995. At this time a new version of the 20v 4A-GE was produced. The new motor has a black cam cover and was therefore named 'Blacktop'. There are several differences between the two, but there is some argument over which engine is 'better'.
Shipping and Compliance the Levins took forever, approximately 6 months waiting for shipping space while Australians were going on a purchasing frenzy of BLACK RAV 4's and other assorted ego boosting SUV equivalents,etc, etc
A Word on Wheel Bearings and CV Joints........ I can only speak for Australia here, but I was surprised to find out that the front wheel bearings and CV joints are not easy to find as they are not common with Corollas sold in Australia. . .
To replace a wheel bearing I had to have the driveshaft pressed out of its spline in the hub - for the same reason I had to replace the bearing - moisture had penetrated it while it was waiting to be shipped from Osaka. I chose KENT ENGINEERING to do this - a local company that specialises in clutch and brakes and also have a load of experience in front wheel drive.
They told me most of the levin driveline components are unique - in size and other ways such as the no of splines on the CV joints and driveshafts.
There may be a match for a Levin non ABS CV joint, with a Ford/Mazda light 4wd ( Courier) but they were not aware of any match for the ABS type.
