engine cooling, not radiator related

[wade3570]

not sure what to search for under forums, so here goes. first of all, i haven't been on here in a while, but finally got the rebuilt engine in and am in the stages of breaking it in for a 1000 miles. (thank you, thank you...bowing)
ok, i have a NA with an intake, header & straight pipes with a magnaflow can. runs & sounds great! The "fibrous" material that lines the underside of the hood was coming all apart years ago and i took it all down. There's obviously a purpose or it wouldn't have been engineered to be there from toyota. I don't have engine overheating issues at all, but everything under the hood after a drive always seems to be extremely hot. I'm a little concerned. How it important is that hood liner? Anybody running without it? should i replace it? are there aftermarket materials?
Also, with the intake hovering right over the header, i'm thinking of fabricating a heat shield to go over the header, not too close. aluminum ok? ideas?
thanks guys.

 

[Orion ZyGarian]

My car didnt have it in for a LONG time. I think its supposed to be for sound suppression, if nothing else.

 

[ms07s]

It is there to protect the paint on your hood from engine heat. Without it expect the center of your hood to discolor and fade faster than anywhere else. I have seen this many times.

 

[trydrew]

Mine gets pretty hot with it, but I am turbo. Do you still have the engine undercover installed?

 

[Orion ZyGarian]

It is there to protect the paint on your hood from engine heat. Without it expect the center of your hood to discolor and fade faster than anywhere else. I have seen this many times.

Actually it was the other way around lol. The hood without it was better than my current hood, but my current one is black from a different car, so I dont know that I can compare them fairly.

 

[zigspeed10]

to help, you could run a lower temp thermostat. What is the outside air temp where you are at? To have excessive heat in the engine bay in the dead of winter may not normal but in a high heat environment heat in the bay is normal.

edit: just read you have a header. you probably don't have a heat sheild. yeah those were there for a reason.

 

[jdub]

to help, you could run a lower temp thermostat.

BZZZZZ...Wrong!

 

[Who]

I've seen a post about removing the rubber gasket seal that runs along the back of the engine compartment where it meets with the hood. Should help to exhaust hot air out the back of the hood.

 

[ms07s]

Actually it was the other way around lol. The hood without it was better than my current hood, but my current one is black from a different car, so I dont know that I can compare them fairly.

I worked in a body shop for several years and currently work at a dealership. Black and red oxidize faster than any other colors. Waxing, washing, climate, and salt water will change the life of your paint. The point is, the cover is to help protect the paint from being heated from both sides and thus making it break down faster. Keep your hood waxed to protect it from the sun and abrasives and keep the undercover to protect it from that hot chunk of metal below it. If you don't beleive me do as you wish, but don't come crying when your hood resembles the moon.

 

[Facime]

Its really a question of whether or not your underhood temps are normal or not. I dont know what exactly a normal temp range should be though, perhaps someone else on here has measured it. You might want to wrap your header in heat wrap, that might reduce the temp some. The hood insulator will not help reduce underhood temps, but it will protect the finish on the hood itself.

Does the car overheat? Are you basing that on a stock gauge (typically not very accurate)

 

[IwantMKIII]

my car is proof the liner is nothing but purposeful.

-its mostly there to prevent excessive heat from ruining your paint, especially important with a turbo

-i learned that its also flame retardent. it prevented a lot of damage to my block by smothering the fire

 

[AJ'S 88NA]

not sure what to search for under forums, so here goes. first of all, i haven't been on here in a while, but finally got the rebuilt engine in and am in the stages of breaking it in for a 1000 miles. (thank you, thank you...bowing)
ok, i have a NA with an intake, header & straight pipes with a magnaflow can. runs & sounds great! The "fibrous" material that lines the underside of the hood was coming all apart years ago and i took it all down. There's obviously a purpose or it wouldn't have been engineered to be there from toyota. I don't have engine overheating issues at all, but everything under the hood after a drive always seems to be extremely hot. I'm a little concerned. How it important is that hood liner? Anybody running without it? should i replace it? are there aftermarket materials?
Also, with the intake hovering right over the header, i'm thinking of fabricating a heat shield to go over the header, not too close. aluminum ok? ideas?
thanks guys.

Just fabing a shield out of aluminum won't help too much. They make a shielding material that has insulation in it. Or you can wrap the header.

 

[Pantaloon007]

I saw something around here in the sticky's about putting washers on the bolts that hold the hood to the hinges to make a gap for air to get out over the winshield. My engine bay gets pretty hot too, so I put about 3/8" worth of washers on and it seems to make a difference. I dont have a thermometer in there to check, so my results arent scientific.

A cooler stat wont do anything but keep your engine cooler which is not always the best thing

 

[cuel]

Wrapping or ceramic coating the header should help drop the temps. under the hood by quite a bit.

 

[wade3570]

ok...the wealth of info on this site is always amazing to me. experience does pay. anyways, well, my temp gauge is reading just below half, which i believe is normal. again, this is a rebuilt motor to spec with toyota parts. yes, i have noticed paint fade on the passenger side probably due to the header. at this point it doesn't matter because i'm getting it re=painted within the next year. i will consider the heat wrap. however, the header is ceramic coated. maybe it needs more. no, i don't have the lower engine cover. it was never on the car since i've had it. ""they make a shielding material that has insulation in it."" what is this? where can i find it? also, i live in tallahassee florida, 90 degrees yesterday, so i'd say pretty hot. ok guys. thanks.

 

[Orion ZyGarian]

I worked in a body shop for several years and currently work at a dealership. Black and red oxidize faster than any other colors. Waxing, washing, climate, and salt water will change the life of your paint. The point is, the cover is to help protect the paint from being heated from both sides and thus making it break down faster. Keep your hood waxed to protect it from the sun and abrasives and keep the undercover to protect it from that hot chunk of metal below it. If you don't beleive me do as you wish, but don't come crying when your hood resembles the moon.

I believe it, but I personally dont care as I have a Red Mica car with a black hood and damage here and there from keeping it in the garage and mom scraping it up. Its pretty bad. Whats important to me is it running as well as it can