on a jeep 4.0 the intake manifold gets as hot as header they are so close, shield it
 

Not sure if anyone has seen a straight six on a 4.0 jeep but on my 95 i have no heat shields on the ehuast aftermarket header or on the bottom of the intake manifold. i know the hotter the motor usually the better fe. But this thing really gets a lot of heat soak would you do a thermal wrap on the bottom of the intake? I was going to wrap the header but nixed that idea and dont want to ruin them by rotting out so what about the intake? i have a WAI already getting warm air off the header just curious if intake is getting wayy to hot or is it a good thing. It has to come off this weekend anyway to replace gasket and ceramic coat the header.

thanks guys, photo below of how close they are

http://images.4wheeloffroad.com/tech...m anifold.jpg

so what do you think keep the intake manifold cool or let it get as hot as the header? what is best for fe

XJ 4-Litre
 

My Mom has a 2000 XJ Sport with the 4.0L Straight-Six. I noticed the same with the intake manifold. The problem is, the IAT sensor is located way ahead of the stream -- close to the throttle body. I'm not sure of knock-sensors on these engines, which could effect timing and FE.

This design helps with Winter temps, but can be a real bugger with hot summer temps. Have you noticed any knocking/pinging at high loads and high temps? If not, you should be OK.

Too bad you're a year shy of ScanGauge compatibility. If you develop an MPGuino or similar to monitor timing, that should tell quite a bit about the heat and engine performance.

Honestly, be glad you have the 4.0 and not the 3.7L V-6!

RH77

We don't have knock sensors. On the Renix 4.0s had em.

Its not that big of a deal really. Probably easiest on JeepsUnlimited's forums (JU) but look for some posts by a dude called DinoSavva, he wrapped his IM with heat shield material and noticed a tiny difference.

Yea see iam pulling off the 95 intake for the 2000 intake for better flow and hp also when i have the intake off i am going to build a heat shield for it and wrap the whole bottum in thermo tech heat wrap

You could try some water injection to drop your manifold temps in summer. I don:t like the placement on the 4.0 either, but it makes it really easy to turbo the thing.

A lot of guys that race Chrysler 2.2s and 2.5s have gained quite a bit of power by having both the intakes and exhaust manifolds ceramic coated. This keeps the temperatures inside of the exhaust from expanding outward and keeps your cool air cool in the intake. The turbo guys do this with even greater success.