ICE Radiant Heat Reflector for the Gen II

I've got a piece of "super insulation/radiant barrier," made up of heavy
duty aluminum foil bonded to both sides of 1/4 inch thick plastic foam.
The piece is about 36 in. by 48 in. I'm thinking about using it as a
radiant heat reflector/thermal blanket over the top of the ICE in my
Gen II. The goal is to help retain heat as the temps drop and help keep
FE/MPGs up. Here's a view of the engine bay:



I won't cover the electronics package on the right, as I don't
want/need it kept warm. By cutting the sheet in half, I can extend
the blanket about halfway down between the ICE and the radiator and
keep well away from the serpentine belt on the far passenger side of
the ICE. By feeling over the top and behind the ICE, I can cover it,
and maybe extend the insulation /barrier half way down the back side.
Here's a picture of the insulation/barrier in place:



I can work the two pieces of insulation around the various bits of
piping and wiring at the front of the ICE, and between the ICE and
electrical boxes going to the rear. Here is a view looking down
between the ICE and the radiator with the insulation in place:



As I'm not going to try to mold the insulation tightly to the
block/head, there will still be an airspace and some moving air
between the insulation/barrier and the block. I expect that the only
real contribution to heat retention will be to reflect radiant heat back
to the block when I'm stopped in traffic with the ICE off and block
temps plummet. I'm thinking the insulation/barrier will stay in place
due the many bends and curves created in working it into place.

I use grill blocking already. I'm using a ScanGaugeII, so I can monitor
ICE temps.

My questions are:
* Have any of my fellow Gen II Prianistas experimented with
something like this?
* If so, did you see any noticeable/measurable FE/MPG results?
* Did you encounter any problems, or incur any damage?

I welcome constructive comments, suggestions, concerns, etc.

(I know what you're thinking....
No, there isn't enough left over foil/foam/foil to make an insulated
aluminum foil hat. )

 

KjF,

I got my scrap piece from a friend.
However, you can get it, or something like it, at Lowes:

Reflectix at Lowe's: 16" x 25' Double Reflective Foil Insulation

 

I thought of that, but it's against the "easy-in, easy-out" nature of
this project as initially conceived. That said, on a 30 mi. trip
earlier today, I monitored both OAT (Outside Air Temp) on the
MFD, and IAT (Inlet Air Temp) on the ScanGauge for the first time.
Outside air was 55 defF, Inlet Air varied beteen 62 and 88 degF.,
with a peak of 92 when stopped with the ICE off. The SG booklet
says that IAT will be "a few degrees" above OAT. That seems like
more than a "few," but since I've got no base line to compare
against, I'm going to have to do some data gathering on this.

I'm also going to check and see how easily the air box is to
remove/replace. If it's quick and easy, I may try this. Thanks.

Sorry. My OP is less than perfect; I didn't make it clear that I am
considering this only for cold weather use this coming winter.

I pulled and poked at that when I opened the hood. I didn't see any
obvious stuff to suggest that it would act as a radiant heat
reflector. I toyed with the idea of putting the stuff I got behind it,
but decided it was too far from the block itself.

As I drove around today watching various temps on the SG, I
thought about this as well. The oil sump is pretty much hanging
out in the breeze under there. Wrapping it would seem to be a good
idea, although I'm not in a position to get under there easily, if at
all. You would also probably need a thin gauge, well attached
aluminum shield to protect from rocks, pebbles, small road debris,
etc. Keeping the shield in place in heavy snow/slush would
be problematic.

For those interested in further reading, here is a thread I found
over at EcoModder:
Insulated Engine? - Fuel Economy, Hypermiling - EcoModder.com

Buried in that thread is this jewel of a link:
Randall's Insight - MIMA Honda Insight Modified Integrated Motor Assist

Holy Cow! a permanent, zippered closure, multi-layered ICE Cozy
sewed of some unnamed fabric/foil/insulation laminate. Hot stuff!

 

I've made two out and back trips of about 30 miles with the radiant
heat reflector/barrier in place. It is too early to quantify any benefit it
may provide. It appears that initial ICE warm up is hastened, WT cools
more slowly at ICE-off stops and no-arrows glide, and steady-state
running block temps are somewhat higher. I'm holding off putting
numbers to these conditions as I collect more data over a longer
period of time, maybe a week or so.

Some casual observations:

For the first time, I've been simultaneously monitoring three temps:
Outside Air Temp (OAT) on the MSD,
ICE cooling Water Temp (WT),
and Inlet Air Temp (IAT)
on my ScanGaugeII. Fascinating stuff. In the discussion that follows,
OAT is between 55-57 degF.

Inlet air Temp is a strange beast. I don't know where it is measured,
but it is subject to great variability:
* it appears to be located close to or in the engine block, head, or
intake manifold because after turing the car off, over a period of ~30
min. temps rise dramatically up to 110 deg in one case. As the car
sits, WT slowly falls, IAT slowly rises. When the two roughly match,
they then fall roughly together. The same thing happens when you sit
ICE-off at a light or in a long, no-arrows glide.
* it appears to react to large volumes of air passing it because with
the ICE running over 2 or 3 minutes, the temp begins to drop.

In general driving around, IAT runs from 5 to 55 degF above OAT. The
higher differentials are reached as the car fully warms up, this is well
beyond the Stage 4 warm up period, at least 20 minutes from start up.
Also, higher differentials occur in roughly steady state driving at
freeway speeds.

I haven't puzzled out what meaningful information I can learn from
further observation of IAT. However, I do wonder how to make head
or tail about the earlier postings about high IA temp with lower
density air and conversely low IA temps and higher density air. With
the 55 degF swings that i've see in very gentle driving in moderate
OATs, there must be a whole lot of computer based compensation
going on in real time. I suppose this is one reason why computer
controlled fuel injection is so vastly superior to a carburetor.

 

Time for a preliminary assessment of this proposed cold weather
thermal retention enhancement.

I've been doing my regular ~28 mi. round trip commute and weekend
errands runs with the radiant barrier in place on my Gen II for 13 days
now. Temps have been between 43 and 63 degF. I'm also running a
full upper grill block, and all but the lowest slot on the lower grill
blocked.

The radiant barrier seems to be having a positive FE/MPG effect. :rockon:

On my commutes, I'm seeing an apparent 2-3 MPG gain. On the stop,
park, and go weekend errand runs, the gain may be as much as 5
MPG. In addition, I am seeing an apparent 5-10 degF higher coolant
temps across the board.

I am being intentionally fuzzy about the possible gains. What with
driving safely and using hyper-mileing tactics, I haven't been able to
record hard coolant temp data despite having a ScanGauge to read
coolant temps and get trip and daily MPG numbers. I have made
numerous runs over very familiar routes, and I am seeing both MPG
numbers and coolant temps that are higher than I would have
expected to see without the barrier.

And that friends is about as good as I can do. FWIW, I plan on keeping
my reflector in all winter.

I'd like to encourage the members who have the more sophisticated
monitoring gear and data recording capabilities to give the barrier a
try and get some good, hard numbers so we can know for sure if this
is worth adding to our cold weather bags of tricks... er, thermal
retention enhancements.