- I received a set of
1.75:1 roller rockers for my TR6 from Creative
Engineering & Design as a "beta" tester for
his new product. I have installed and evaluated the product on
my daily driver '74 TR6 and I'm presenting the results of my experience
on this web page.
The package I received was well packed and included very good
installation instructions.
I started the project by reading the manual to ensure I would
get the installation correct. The manual is very detailed (including
illustrations and pictures) so any novice mechanic should be ale
to perform this job. I removed the old rocker assembly and laid
all the new rockers out in the order they would be installed.
I removed the old rockers. My rocker shaft was in good shape (having
been replaced in the last 8k miles) so I was able to reuse the
shaft. If your car has very many miles, you probably need to replace
the shaft as they are very prone to wear.
I reassembled the rocker assembly using the new rocker arms. A
good diagram is provided that will assist you in getting the assembly
order correct.
I trial fitted the new rocker assembly and found I had some push
rod binding against the cylinder head in several locations. I
have checked with Jim Swarthout (the owner of Creative Engineering
& Design) and it has been discovered that if you are using
OEM push rods you will not experience push rod binding. If you
are using after market push rods, then you could possibly have
push rod binding. After market push rods have a larger diameter
which cause the push rod binding. My push rods were replaced with
after market push rods when I rebuilt the engine. To remedy the
problem I marked the path of the push rods on the cylinder head
and then removed the rocker assembly and push rods. Take care
to keep the push rods in the correct order for reassembly. I then
cut and pushed rags into the push rod gallery to prevent metal
filings from entering the engine. I cleaned the areas with carb
cleaner and then used a dremel tool to remove material from the
cylinder head to ensure the push rods would have adequate clearance.
The push rod is closest to the head when the valve is closed so
you only need to remove enough material to ensure the push rod
does not contact the cylinder head with the valve closed. After
the grinding was complete, I took a shop vac and vacuumed all
the material up and then carefully removed the rags. I reinstalled
the rocker assembly and ensured I had clearance between the cylinder
head and the push rods
The next step is to
set the valve clearance using instructions from the manual. A
nice laminated shop card is included that details valve adjustment
procedures. After the adjustment I fired the engine up and ensure
all rockers were oiling.
After the installation was complete it's time for a test drive.
I'm pleased to put it mildly. The car picked up some more bottom
end and midrange power. I also picked up some more "useable"
RPM on the top end and the engine sounds throatier when you open
the dual webers up. Before the installation, the webers wouldn't
really"moan" when you hit the secondaries. After the
installation they will moan so I'm obviously moving more air/fuel
mixture through the engine than before. This is a daily driver
so I was concerned about a rough idle. The rockers did not change
the smoothness of the idle. I also noticed the valve train is
somewhat quieter after the installation. I suspect this may be
because the roller is more efficient than the stock rocker arm
and with less side loading on the valve stem. Also, the elimination
of the side loading on the valve stem should increase the life
span of your valve guides.
Engine Details:
1974 block with 15k on a rebuild
Stock camshaft
Early cylinder head (bigger valves, higher compression)
No emissions controls
Dual weber DGV downdraft carbs
Stock exhaust
Crane electronic ignition w/Lucas sport coil
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Well packed, good instructions
Removing the rocker assembly
The old rocker assembly is ready for disassembly
New rockers laid out in the order they will be
installed
New rockers installed on the shaft
New rockers with adjusters installed
Push rod binding occurred here #1 valve
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