Now that my truck is up and running finally (22R- 261C cam, header and 2.25" exhaust) I've noticed that the header seems to get really hot. You can really notice this if you touch the hood on the side which the header sits under.... after doing a bit of driving and wheeling today, I put my hand on the hood and it was freakin hot! <img src="/forums/images/graemlins/scared.gif" alt="" /> (to a point where it would be uncomforatable to keep it held on there!)

Is this typical for having an aftermarket header and no heat shield anymore? Would header wrap be a good idea at all? (although there seems to be a good amount of pros and cons from what I've read). It's not affecting my engine temps at all (I've got a nice big 3 core rad and a good working fan), but I'm just not sure if it's normal for a header to get the surrounding areas that hot.

They make header wrap for a reason. <img src="/forums/images/graemlins/smile.gif" alt="" /> Sounds like a pit stop by NAPA, esp if your feet are feeling a little warm too! How's the new config running?

I don't see what the con for header wrap would be; what were you reading?

Con....



moisture gets trapted and rusts out the header.

I'd endure that over burning up my ignition/charging system!! <img src="/forums/images/graemlins/lol.gif" alt="" /> MUCH cheaper to replace; on this end of the planet anyway. Thanks for the input Tater!

I always wondered why no one seemed to come up with an adapter shield; too much hassle I guess.

I put the cat on for smog and it feels like the heater is on all of the time.
It seems to make the Header run a lot hotter!


<img src="/forums/images/graemlins/angry.gif" alt="" />

Headers dissipate heat faster than a cast iron manifold, so yes, there is more heat under the hood. That's why ceramic coating is used on a lot of headers.

Cons, besides moisture, header wrap retains too much heat and will make the metal brittle. Over time the header will crack. Why do they use it in racing? Because it does reduce underhood temps and they really don't care about swapping out headers every so often, part of racing. Plus they probably get them for free or close to. Remember what works in racing doesn't always work on the street.

moisture and brittle headers, BAH!

I've been using it for nearly five years now. I recently (on the third year) pulled my downey 4:1 header to install a thorley tri-y. the downey was wrapped for 3 years. I originally installed header wrap because of the heat issue and to reduce the noise associated with headers. out of curiosity, I pulled the header wrap to see if the metal was fatigued or "melted" (some guys claim you can heat your header to the point of melting it if you wrap it - total bs.) and aside from minor surface discoloration and a little rust, there was no noticeable damage to the header. there was one spot down near the collector where all four tubes come together that had some rust flakes, but other than that, tip top shape.

I have my thorley wrapped, and will continue to wrap any future headers I install. I much prefer the reduced engine bay temps along with the reduction in the header tick noise. I'd rather cook a header (if that can even happen with a daily driver) than heat damage other components in my engine bay, which is more likely with the increased temp a header puts out.

but that's just the humble opinion of person who's actually used the stuff.

I had the header on my old FJ-55 header (F engine) wrapped and had no problems with it for many years that I drove it. To help seal up the wrap, I saturated it with silver hi-temp exhaust paint and that seemed to help keep the moisture out of the wrap.

The LC header I have in the 4Runner has the ceramic coating and that seems to help quite a bit. You could always send the header out to Jet Hot and have it ceramic coated.

Header wrap does trap moisture,thus increasing the chance of rust. However, if your truck is driven often (like a Toy should)it has little chance to ever take hold. In other news the wrap increases scavenging through increased velocity in the exhaust so you may expect some power/mileage increase. <img src="/forums/images/graemlins/cheers.gif" alt="" />