Stewart Components Top Ten FAQ
The following is a list of the 10 most frequently asked
questions that we receive at Stewart Components.
If your question is not answered
here please browse through our Tech Info Section and our
Q&A Forum. If you still cannot find the answers you
need, post a question to the
Forum and someone
will try to help you answer your questions.
Will the Stewart Hi-Flow water pump reduce my cooling
Yes. The water pump is the heart of the cooling system
and flow should always be maximized to reduce
Which pump is best for my application (cast iron or
Both are Hi-Flow and will work
well although the aluminum version is available in a
hand polished finish.
Do I need to run a thermostat
and what is the best kind?
Most street driven vehicles should use a thermostat and
we recommend the Stewart/Robert Shaw hi-performance one
that we modify for better cooling.
What about my pulley
set-up (what ratio do I need)?
For STREET applications, the water pump speed must at
least match the crankshaft RPM, to a maximum of 10%
faster than the crankshaft speed.
My engine runs cool enough
out on the highway but heats up at slow driving or at
idle. What is most likely the problem?
Most stock or OEM pumps are built to meet standard
performance requirements and at low RPMs the flow is
reduced, the Stewart Hi-Flow water pump is designed to
produce increased flow at idle as well as higher RPMs.
What is the best coolant
If freezing is not a concern we recommend water with a
corrosion inhibitor. If freezing is a concern, use the
proper amount of antifreeze required for your climate.
Which radiator is
recommended (aluminum or copper)?
We strongly recommend aluminum radiators. They dissipate
heat more efficiently than copper brass.
What size radiator should
I use for my application?
We recommend using the largest (in surface area) that
will fit into your vehicle.
What would be the correct
pressure cap rating to use?
We recommend using a radiator cap with the highest
pressure rating that the radiator is designed to accept.
Which cooling fan do you
recommend (electric or mechanical)?
Electric fans now outperform mechanical fans in nearly