From 1975 to 1982 Toyota
produced the 20R & 22R four-cylinder engines that utilized a dual timing
chain system. It proved to be very dependable and included steel timing
chain guides. Then in 1983, Toyota decided to install the single row chain
with plastic guides on all of their 22R engines.
The single row timing chain is prone to stretching beyond the
tensioner's limits, resulting in a loose chain. As the chain stretches,
several things can occur. You experience improper camshaft timing, the
plastic guides eventually break, the timing chain can either wear a hole
in the timing cover or break entirely sending the pistons and valves to
meet their fate. Not a pretty picture. LCE does supply a very heavy-duty
single row chain with metal guides to give a little more life expectancy.
From 1985 to 1995, Toyota was still producing the single row
timing chain for the 22R series engine, but made the deck height of the
block and cylinder head shorter. This changed the centerline distance
between the crankshaft and camshaft resulting in a shorter chain. Toyota
recommends that you replace the single row chain every 70 to 80k miles.
As the evolution of our performance engines took place, LCE
was experiencing problems with the single row timing chain. So, in 1995 we
designed and started to manufacture the Dual Row Timing Chain Conversion
Kit for the late 22R series engines. What a positive impact this made on
the quality and performance of our engine packages. This kit is also
available for those who want to convert their 85-95-22R series engine over
to the dual row chain.
LCE has spent countless hours on our engine dyno machine
developing the proven quality products that we have provided our customers
for the past 16 years. Please refer to our catalog, web site or call a
very experienced sales staff at 928-505-2501 for details. |