Unwanted engine bay heat.


"One test is worth a thousand expert opinions."
I have an 84 Trans Am. As you might know, these cars have tight engine compartments, no
front grilles, and lower hood lines than Camaros. When I finally get the 334 re-installed, my
Turbo "bulge" hood should just close - I hope. The intake manifold is a Weiand 8000,
Edelbrock 1904 Quadrajet, and the dual-snorkel air cleaner that came on the 305 HO engines.
I will gain a little room, and hopefully some under hood airflow, by no longer having the
computer control and its wiring & hoses, removal of A/C as well as deleting that huge
heater box, removal of the air pump, and mounting the passenger side mounted alternator
lower. I already removed the "cold-air induction" mechanism from the underside of the hood in
an attempt to let hot air out.
And I swapped the solid inserts in the front bumper for the grille inserts.

Eventually I would like to swap the intake for an Edelbrock Performer RPM Q-Jet, which is
supposed to be worth 20 HP over the Weiand 8000, but it is taller and I would need a taller
hood at that point. Also a taller hood would let me use the 1" taller air cleaner lid and filter for
less restriction.

Some photos (not necessarily my TA):
[005939].jpg 4F9E_3.JPG 52CD_3.JPG hose routing.jpg emission hose routing.jpg untitled1277_3d0b08a1ac549a08a02bde54ccd576bd654e47d7_7d7390be9700bf86a327a472cf54f3620c0d896d.png ac 2.JPG Heater & AC box.jpg HeaterBox_071212_3.jpg f-body non-ac 2.jpg
I am also using SLP stainless steel headers that I will be removing the air injection tubes from,
now that the car will not be computer controlled. I was going to sandblast and paint with Dupli-
Color's new header paint. But I really don't think that will last for very long, so if the cost for
Jet-Hot coatings (or one of the other brands) is reasonable, then I might go in that direction if it
actually reduces under hood temperatures as much as they claim. Does anyone have an opinion
on good header coatings?

To be continued with aftermarket hood choices.....
You could try using VHT HEADER PAINTS MIKE.
I am uploading photos taken today .
VHT Header painted my New Oldsmobile Starfire Exhaust Manifolds.
Very good results .
We used it in rhe race shop I worked inl last Year.
Turbo car guys Love Header wrap .
Just works great.
Your not supposed to wrap stainless steel headers.
Can cause cracking of the stainless tubes.
Stainless steel actually has a very high thermal expansion rate Verses Mild steel headers like Hooker or Headman.
Jet Hot thermal coatings are not impervious . IF EGT'S Get to Hot , blistering of the coating can and will occur.
Well, they are 409 SS. Supposed to be the most thermally stable type, they claim.
They also tarnish -looks like rust but not. The definitely don't stay shiny like a sink.
Maybe I will have to use a ceramic coating - only if it will reduce under hood temps.
I won't spend the money just for looks. Budget $ always a factor.

Post those pics. And do you mean a 75-80 Olds Starfire?
The photo above is close to what I would like to end up with - an engine compartment with an engine
where you can actually see the valve covers. Anything unnecessary GONE. And easy to work on.

Some hood choices:
ed_108493_1.jpg I think this one would be a problem in the rain.
trans am hood 2x.jpg I was liking this one, but I think the "nostrils" are too far forward. It's too wide at the back.
firebirdhoodisma2a.jpg firebirdhoodisma3a.jpg Better, but no cool air inlet(s). But I like the rear much better.
PCM-Firebird-21-copy-e1412315786627.jpg Way too wide at the back, and might not be tall enough.
34.jpg This might be Okay. With the cut-outs opened up.
firebirdhoodramair4a.jpg firebirdhoodramair4b.jpg firebirdhoodramair4d.jpg I like this. The "nostrils" begin further back,
and the rear portion does not extend all the way to the windshield. And it has the cut-outs for
the factory heat extractors. Does anyone know if those heat extractors work?
But I don't think this hood is available anymore, if it ever was.

I only want a cool air inlet, and hot air outlet, to create an airflow to remove engine bay heat.
I will not be connecting the air cleaner/carb to any ram or cowl induction air. I will still use
the factory dual snorkel air cleaner.
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Grumpy is an expert on Heat extraction........Summer time heat & humidity in Florida....From what I hear its bad,.....weak will die there without Air Conditioning.
He will be around in the morning.

425 Olds Starfire Mike.
1965 - 1967.
Yours did not either.
The system servers must be slow.
Your pictures showed up 5 minutes ago.

Look at my 1965 Olds 425 A thread on recent posts, Main page.
See more pictures.
Thermal expansion is virtually the same between 409 SS and carbon steel. 304 SS has a thermal expansion more than double.
Yes, ceramic coatings do decrease Underhood temperatures by as much as 50%

The full anti-corrosion benefits of header coatings requires coating the headers on their inside as well as outside surfaces. Not coating both inside and outside of your headers isn’t good because exhaust gases themselves contain corrosive compounds. If the inside isn’t coated, the header eventually rusts through from the inside out. Coating only the outside can also cause another problem: Mild steel tubing fatigues when it gets too hot. An outer-only thermal barrier blocks the heat from radiating through the exterior metal surface, while the lack of an inner barrier exposes the metal to added “trapped” heat. So, with that said I would never recommend "wrapping" headers.

The ceramic coating’s ability to trap heat aids a marginal engine coolant system in a closely cowled musclecar by reducing underhood temperatures. And as installed in a real car, lowering the ambient temperatures could also allow a cooler, denser fuel/air charge to reach the combustion chambers, offering more power-making potential.

By retaining heat within headers, the coating is also said to increase exhaust-gas velocity because hot gasses expand and travel faster. By smoothing the internal header bore surfaces, turbulence is reduced. The net result is more effective cylinder scavenging, which yet again offers a potential power increase.

Headers aren’t the only parts that benefit from Ceramic coating; it can also be used on exhaust pipes, mufflers, and even (for emissions-reducing quicker light-off times) the catalytic converter. By applying Coating only to the top and bottom intake manifold surfaces, as well as the outer surfaces of turbocharger ducting, centrifugal supercharger ducting, and fuel-injection system air-intake tracts, you can keep incoming air and fuel cooler by insulating the charge from radiant engine-compartment heat. The extra cost justifies the end results and there is literally hundreds of tests both by the manufactures and independent labs all supporting the same benefits.
Every single of Smokey Yunicks Race Winning Small Block Chevies used Long tube headers wrapped in Fiberglass Thermal Tape.
With the engine running you can touch the header tubes with your Bare Fingers and not get burnt.
Can't do that with Jet Hot style Thermal coated headers. Burn the crap out of your fingers.
Headers are an expendable item on Race cars
Expected to last 1-2 race season years.
Street guys expect more.

Weigh options and decide .
To Jet Hot style Thermal barrier coat all in a Dual exhaust system it will cost $2,000 + Cash.
Since this group has no Racing sponsors money is tight for all.

ok, first I'll point out heat control is basically a three phase, or level, issue, and youll want to maximize the engine efficiency with an auxiliary oil & transmission fluid cooler Plus, as these can significantly reduce heat the radiator has to deal with,and adding a larger more effective multi core aluminum radiator, with properly ducted fans if you can afford it and have the room, will certainly speed up and help the heat transfer rates.
I find it rather amazing that many guys (even a few corvette owners) don,t realize that the oil cooler between the block and oil filter does remove a noticeable amount of heat from the engine oil, or that in some cases that they even have an oil cooler factory installed. ITS OIL FLOW that absorbs and initially transfers heat away from the bearings and valve train not coolant.
my 1985 corvette came with a factory oil cooler, that runs engine coolant through separate but contacting internal passages, this warms the oil faster getting it flowing but tends to reduce the heat engine oil can reach as it absorbs oil heat effectively transferring it too the engine coolant on the car, where its transferred too air flow through the radiator,

what I find absolutely amazing is the number of people that have ordered replacement radiators ,
without accurately measuring the original radiator, and then accurately, measuring, the space its seated been in,
and the distance available in front of the O.E.M radiator and behind that original radiator,
if you want too select and install a thicker, more efficient heat transfer core, aftermarket radiator
thats thicker has more fins and surface area and larger coolant flow tubes.
one fact often over looked is that radiator designs vary wildly, and the number of fins per inch of surface area and width of radiator coolant flow tubes can significantly increase or decrease thermal heat transfer efficiency., fin counts vary from 8 to 22 fins per inch on various radiator designs Ive seen.
thus a radiator might measure say 18" tall by 24" wide but depending on design, and fin and tube count, might actually have a radically more or less efficient heat transfer rate.







large hood heat extraction, vents and an efficient radiator fan and duct work can significantly reduce the time air might be trapped in an around the headers and engine thus reducing the time the air has to absorb heat thus lowering the engine compartment temperatures, get the fuel/air ratio or ignition advance curve set-up wrong and tyoull have significantly more heat energy wasted in the engine compartment

I don,t remember, where I purchased most of the oil/trans fluid coolers Ive used ,
but I've purchased and installed several oil and trans fluid coolers
over the decades, almost all were used 1/2" or an#8 connections and were purchased from summit or jegs
as always read carefully,
and measure accurately, remembering you must be leaving room for the hot oil or trans fluid hose and connections
and access to get the cooler in and mounted and connections made too it!
you would certainly not be the first or last guy to buy a cooler that will not fit in the space you though it would,
due to the connections and hoses required or forgetting about the thickness or lack of easy access.
yes adding an auxiliary electrical fan cooled,
oil cooler and or trans fluid cooler,
does drop your engines operational temps and in the case of transmissions,
a trans fluid cooler,
and reduces the heat load on the existing radiator.
btw, adding a few accurate dash gauges ,
to monitor the fluid temps certainly won,t hurt either.







https://www.summitracing.com/search?PageSize=100&SortBy=BestKeywordMatch&SortOrder=Ascending&keyword=oil cooler with fan



(1) control of engine produced heat being generated , is the first step
a large baffled oil pan, an auxiliary oil and trans fluid cooler , and correctly tuning the engines fuel air ratio and ignition advance curve, and a larger radiator and ducted fan can all reduce heat







(2) ceramic header coatings can significantly reduce engine compartment heat transfer rates, as the thermal coating significantly reduce heat from the exhaust from entering the engine compartment


you'll want too stop and think things carefully and measure accurately

its never a bad idea to measure the oil and transmission fluid temps during your cars operation, this is the most consistently accurate I.R temp gun I've used for testing

http://www.testequipmentdepot.com/e...1100200223789&utm_content=All Extech Products
Wide temperature range from -58 to 1832°F (-50 to 1000°C)
any time that your dealing with a potential temperature issue or a trouble issue where , knowing the exact temperature vs what a gauge might say, it helps to have a handy and accurate infrared temp gun handy to locate and confirm heat, levels.




(3) rapid and significant transfer of heat to the outside mass of air flow







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That chart is not accurate measuring the hp/tq between paint and coating.
A car strapped down on a chassis dyno with the hood fully open and hurricane fans blowing isn't nearly the same as a car running under real driving conditions
Thanks guys. Good info. I will have to check out all the links later, but right now I'm leaning
towards coating the headers and Y pipe up to the "fake" catalytic converter. This will reduce
under hood temps and also help with not essentially having a heater directly under the oil pan.
Fake meaning that I plan to fabricate a "catalytic muffler". I cut the case of an old cat converter
open and I'm going to use a 4" SS pipe inside (cat is 3" IN & OUT, oval case) that I will drill holes
in opposite sides to perforate it. Then I will pack SS scrubber pads between those holes and the
case (like a glasspack, but without the fiberglass to burn out). Inside of the 4" pipe will be a SS
spiral insert - the center tube is 1.5". I'm hoping this will break up the sound wave to make the car
quieter, without hurting the flow. A portion of the exhaust will flow straight through the 1.5" pipe.
The rest will take the longer path around the spirals, being dampened along the way by the holes
in the 4" pipe and SS scrubber pads. The 2 exhaust streams will join back together at the exit end,
and then to the SS transverse muffler at the back of the car.
Even though I do not have to go through emissions anymore, I still want it to look like a working
converter is still there. Plus it adds to the sleeper disguise. I have blown up the transverse mounted
SS muffler all the way at the back of the car in the past. And a working cat converter was in there
at the time.
Can I get recommendations for coating companies, please?

If you think about it a bit all a knock sensor does is retard ignition advance timing,
to the point the engine no longer detonates due to too much heat in the combustion chamber for the advance curve and fuel octane.
obviously if you have experience tuning a certain engine and your fuel octane is fairly consistent, you can change the ignition advance curve to match ,
the engines documented and tested power potential.
that does not mean a knock sensor is not useful , simply because fuel quality and engine cooling efficiency varies with outside air temps.
and your cars radiator and oil and trans fluid cooling efficiency, but a good tuner can avoid getting into detonation range, with a known engine combo, a high percentage of the time.
obviously boosting your fuels octane, and fuel to air ratio to cool the combustion helps so thats the first part of the equation,
retarding the cam timing reduces effective compression,
retarding the ignition curve will reduce cylinder heat and effective pressure,
all factors should reduce detonation,
easily 60% of the most common engine detonation is not in the normal adult humans hearing range
detonation damage is cumulative!













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I can see the pics of you manifolds now. They look great. I hope that VHT paint holds up.
Too bad the outlets are so small. I see you used a heat gun to cure the paint. I use my
oven - no wife.