IC question 4 More power was Drag times

Marc Swanson mswanson at sonitrol.net
Thu Nov 20 12:05:17 EST 2003

> I noticed the IC's are sideways, which must have air ducted to them.
> My question(s) are:
> Straight ram air best to have IC function at optimum?

Corky bell in his book "Maximum Boost" actually recommends ducts for
even straight forward facing ICs (where the ducts point inward,
preventing air from going around the core).  I think the reason that
most tuners choose to mount the IC up front with no ducting is simply an
issue of size... with such a big IC you can't really put in a whole lot
of ducting.  I'm sure that by side mounting a set of intercoolers you
could duct well enough to get the same effective airflow as a plain FMIC
if you are careful about it.

One thing to note though, the AWE S4 is using water to air
intercoolers.. they can mount those wherever they want since the cooling
is done through a separate radiator.

> Is there a General rule regarding IC size and piping size?

it is a function of required air flow.  if you make your piping too
large for a given setup you will increase the pressure drop in the
system without giving yourself any benefit in flow.  Given the size of
the I5 and the air flow you would need for about 300hp, anywhere from
2.25-2.5" diameter pipes would be just fine.

> Would two IC's in parallel, (Duct outflow from first IC into second IC then
> to intake.
> be a budget way to further cool the intake charge?  I can see space an
> issue.

If you feel you can get a significant amount more core area using a dual
intercooler setup then it might give you better efficiency than a large
single IC.  As an example, the 225hp TT uses dual intercoolers, and that
is naturally a single turbo car, so it IS done.  That said, if you can
fit the big single IC I'd go that route personally.

Best Regards
87' 4ktq
88' 90q

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