Thermal wrap effectiveness?

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

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...

I take back the good results from the starter wrap. After driving 30 miles yesterday the starter was heat soaked and just about got the car restarted. I'm pulling the right side header and going to wrap it only in the location near the starter.