Intake Manifold temp

[akadeutsch]

After installing this stainless header with no insulation between it and the stock 99+ intake manifold I attached a thermocouple to the top of the intake manifold and read temp during idle, then in stop and go traffic, and then again at highway speed. Here is what I found.
After driving to the grocery store (far enough to warm up to operating temp) I went in to shop (20 min). When I came back out, before I started the truck the temp of the intake manifold was 162°F and climbing. The drive home was stop and go and the temp got as high as 140°F while stopped and 130°F while driving under 45 mph. If I cruse steady at 45 mph the temp will drop to 120°F on the top of the intake manifold. And on the highway the temp will hold around 110°F.
Today I ordered some Thermo Tec exhaust wrap. I am going to wrap the header and then collect more temp data. Does anyone out there have any data regarding stock intake manifold temperature during operation?

I want to get my intake air temp as low as possible.

any advice?

[Root Moose]

Here's what I did with mine. It's probably a good example of "quick and dirty" or more likely how not to do it but the main thing I figure is to wrap the cats. I was short on time and material when I did this - critical path to our family ~8000 km road trip was three days at this point IIRC.

I didin't have it instrumented but I expect it helped.

I didn't wrap the headers themselves as I didn't have enough material and did not have time.

This probably helped the most:



Then I draped the little bit of material under the intake manifold and tried to protect the intake manifold that way. It's not shown very well in these images but it is more or less pinned enough to not flutter when the fans are on.



I had one small piece left that I put on the top of the intake manifold:



Completed:



When I have to pull the head again over the winter I will redo it properly and re-wrap the intake manifold completely. It's not 100% coverage now and I worry that being draped like this there is potential for oil spills to collect on the material and ultimately ignite if it really gets saturated. I had an issue with a leaking power steering pump while in road tripping and it sprayed a lot of fluid around over the course of a few weeks - not on the material though in this case.

[Cheromaniac]

After driving to the grocery store (far enough to warm up to operating temp) I went in to shop (20 min). When I came back out, before I started the truck the temp of the intake manifold was 162°F and climbing. The drive home was stop and go and the temp got as high as 140°F while stopped and 130°F while driving under 45 mph. If I cruse steady at 45 mph the temp will drop to 120°F on the top of the intake manifold. And on the highway the temp will hold around 110°F.
Today I ordered some Thermo Tec exhaust wrap. I am going to wrap the header and then collect more temp data. Does anyone out there have any data regarding stock intake manifold temperature during operation?

Yup. I collected some temp. data years ago before and after sticking a Thermotec heat blanket on the underside of my intake manifold. Here's my article:

http://www.angelfire.com/my/fan/manifold.html

[akadeutsch]

Hey, thanks for posting. I like what you did. I wish you had some temp data to prove it worked. What was that matierial called? I dont have cats on the down pipes like you do, but I will still wrap the pipe.

[jeepxj3]

You put your thermocoupler on the outside of the intake manifold?

Don't you want the temp on the inside? Of the intake air?

[akadeutsch]

I agree that it would be better data coming from inside the many. But I am not really looking for accuracy here as much as I am looking for a comparable difference. In other words, I don't really care what the exact temp of the air is. I just want to make it cooler. So as long as I take my readings from the same place I will the get the consistent data that I am looking for. And although it would be more accurate to measure your way, I think I can achieve very similar results this way...without dismantling my truck to place a t/c.

[Cheromaniac]

Hey, thanks for posting. I like what you did. I wish you had some temp data to prove it worked.

I took some temp. readings with the probe of my digital thermometer secured onto the IAT sensor before and after doing this mod. I took readings at a steady 20mph, 40mph and 60mph with the outside temp. at 95*F each time. The results were as follows:

Idle: Without heatshield-increases in seconds to 160+*F, With heatshield-much slower rise in underhood temp.
20mph: Without heatshield 157*F, With heatshield 132*F
40mph: Without heatshield 139*F, With heatshield 122*F
60mph: Without heatshield 127*F, With heatshield 121*F

[akadeutsch]

Aw yes. That is exactly what I was looking for. The temp here is getting pretty cold so I will probably not worry about this until it starts to warm up a bit. Thanks for the info.