Thermal wrap effectiveness?

NIKwoaC

中國製造
15 Year Member
Oct 31, 2006
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Chengdu Province
Not really looking for a performance gain out of this, but really just trying to save on under hood component lifespan.

I've been having hot start issues and I'm pretty confident my chrome BBK equal length shorties are baking my starter, thus causing the problem.

Because I don't want to dump money into redoing my exhaust setup right now, and I plan on eventually going 351+ anyway, switching to ceramic coated headers is out of the question.

So, does thermal header wrap really work? Is there any type that works better than others?
 
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Header wraps work as far as keeping underhood temps down, but it is very hard on headers. It causes them to rust faster than normal, most header mfr's won't warranty a header that's been wrapped.
 
Sounds like the header wrap will just be covering up the problem.

They work, but they trap moisture, i've heard of peoples headers having rust holes in them after a year, I've heard of people having them last longer.
 
Wrap the starter, not the headers. Aside from rust issues associated with wrapping the header, it also "superheats" the metal. This is great for scavenging purposes and increasing exhaust velocities, but really shortens the life of the header. Where a lot of said heat would have normally transferred out under the hood, it now stays inside the exhaust itself. This causes the metal to overheat and become brittle and prone to cracking.

The only coating I would consider for a header would be a true Jet Hot Ceramic set up both inside and out. Not only will it control under hood temperatures, but it will increase the life of the header itself. Anything else is going to have a downside in the long run.
 
I hesitate to wrap the starter, because at first it will keep the heat out, but eventually it will keep the heat IN, especially after driving the car for long periods of time. Also, the starter seems like something that would be much more prone to failure by trapped moisture than what headers would.

What about some sort of a fabricated heat shield? Seems like 10 minutes in a junk yard and some garage ingenuity would have something pretty functional. Whaddya think? :shrug:

BTW, thanks for the replies, fellas. I think header wrap looks kind of cool in a traditional salt flats hot rod sort of way, so I guess I'm a little let down, haha. But I believe in function over form, so I'll have to avoid the wrap and find another solution.
 
I got the starter wrap today an installed it. It a woven fiberglass mesh with a shinny silver reflective finish on the outside. It's the type of material that a worker in a steel mill might be wearing. I ran the car for twenty minutes and shut it down, waited a minute and started it back up with no problem. I guess that it's working.
 
Hmmm ... been having the same issue, myself, on both my '84 and my '89. I upgraded to a mini-starter on the '84 because the starter I had on there was REALLY bad about heat soak (even though it would bench-test perfectly fine, even when it was still pretty hot), but I can still hear it turning over a little slower when the engine's warmed up and I've been driving for a few minutes VS when I'm cold-starting. The '89 has a stock-style starter which I already replaced once with a brand-spankin' new one (not a reman), and it still has the same issue. I have clean connections and new cable, but I never thought to upgrade to 2-gauge cable in either case. Might hafta try that, perhaps in addition to the starter wrap.

FWIW, I don't see a metal heat shield as having much potential because metal conducts heat rather than blocking it - it would work at first, but once the metal of the shield heats up, then you have a hot piece of metal hanging right close to (or bolted directly onto) your starter and you'll still have the same outcome. I've seen metal heat shields on a lot of GM starters that just sort of clip onto the starter solenoid, so you if there's room under there you might be able to find one of those in a junkyard (I think they even sell them in the HELP! section of parts stores), and then poke one of those on there to see if it helps a little, but I wouldn't expect any miracles.
 
my BBK long tubes are wrapped with Thermo-Tec header wrap and then painted with their high heat header wrap paint... the dyno sheets on their website show some impressive gains on high horsepower applications due to the increased scavenging and velocity of escaping exhaust gases... i'm not too worried about the rust issue as of right now, my car lives under a car port and doesn't ever get driven in the rain :shrug:

check out Thermo-Tec: Dynamometer Tests
 
First off, heat wrap is a PITA to install, especially if you have tight clearances. Your starter issue can be solved by converting to a 92 starter setup. It's smaller, leaving more room between the starter and header. A heat shield will block radiant heat, which is heating up your starter. Header wrap will solve the starter problem for the future (make them last longer) and protect everything else in your engine compartment.

If you want to get ceramic coated headers in a couple years, drive in mostly dry weather, and want to spend a few hours wrapping your headers (wear a mask) go for the wrap.

Otherwise, get a new 92 starter set-up, at most add a shield.

Moisture should evaporate off the wrap...