What Mod Next? Larger Tb/wrap Header?
 

95 JEEP 4.0 6CYL.

I have a ceramic coated aftermarket better flowing header and have been told wrapping the header will keep heat in and better MPG, i have to pull it anyway to do a new gasket so while its off i thought to do it?

Also while intake has to come off ive gone to the better flowing one off the 2000 jeep intake manifold which adds 15 hp to the older 4.0 jeep motors that have the bad flowing intake manifold. while changing out my old intake manifold i have been told a larger throttle body is better for mpg too and will go well with the new intake and exhaust combination.

I already have a 3 inch intake Warm air off the header. i guess my header wont be as hot as it used to be if i wrap it just curious probably wont affect the wai that much.

The header wrap keeps engine bay temps down and is a little counter productive to what you are going for. Wrapping the exhaust from the header down can keep exhaust gas temps up and therefore EGV stays up but you'll lose a lot of your WAI functionality if you wrap the header.

Maybe combine a wrapped header with a grille block? Then again with a grille block the wrapped header won't be as important.

I wont block the grill, i have a tranny cooler, oil cooler, and hydrogen cooler in the grill. Plus my jeep see's no highway driving only city not many lights 35 to 45 mph.

as for wrapping the header it does keep heat down but not totally gone so i think the wai will still work good.

My truck drives mostly in urban areas. My average speed reported by Scangauge is usually only about 15 - 20 MPH. When I installed the grille block I made sure that the holes in the block were put right in front of the oil and tranny coolers. I agree. Those things need to breathe, but you can still do a grille block.

-Jay

header wrap will kill your ceramic coating over time. a larger tb is definitely NOT good for mpg. it will be a lot easier to throw too much fuel in the motor. you will improve throttle response though...

I second the "NO Larger TB" opinion.

In my observations of the 4.0L I6, I find that staying out of 2500+ RPM is ideal. I do not gain any power above 2500. To see for your self, try shifting at 1800 RPMs and no higher. The engine has plenty of low end torque and is very hard to stall under load.

Throwing money on larger TB and header wrap is an effort to increase HP which leads to more fuel consumption.

i drive like an old lady, hypermill all the time and shut her off on this 1 2 mie hill everyday. So still no larger throttle body.

What about the header rap i thought that would be a gaurantee for better mpg

how again?

have you done an electric fan swap? those tend to help, but since uve got the 4.0 i dont know if it would help all that much...

Sorry i just wanted to clarify that the header wrap doesnt improve the fe, as for the throttle body i drive like an old lady and dont get above 2500 like ever just figured more air the better.

as for the fan yea already have the electric fan it comes on at like 205 is that a good degree

yea i wont do header wrap it will just rot them from inside out, as for the TB im still not sure on that yet

another no on the TB. the only time a larger tb helps is WOT at high rpm, unless youve done alot already to help your engine breathe, it might not even help at all.
the feeling of increased throttle response from a larger TB is in perception only. with a larger tb opening the throttle 25% way feels like opening a stock tb 30% or so.... because thats what its equal to in air flow. anyone that likes this throttle response would be better served stabbing the gas pedal a little harder and faster.

i've been there done that... few years ago,modded an 89 camaro about as fast as one could be w/ stock heads and no power adders. larger TB was the biggest waste of money i've had on any vehicle mod ever. i think i actually got worse mileage with the big tb. larger tb makes it more difficult to modulate the throttle because it lets more air in faster, twice as bad in an overpowered vehicle. i was always touching the throttle, tring to back off, coasting, getting on the throttle some...

big TB = bad idea

Yep the wrap will ruin the header, because the header gets so hot that it will just erode.

... no i dont think thats it. the header wrap will hold onto moisture which will rot the header.

I read some where that because the header gets so hot from the wrap it can't cool down enough, so the header is some what molten which makes it erode. You are correct too. It does hold on to moisture.

Moisture means it depends on where you live. Here, humidity is regularly under 30% most of the year and I can tell you with utmost certainty that the wrap isn't holding on to ANY moisture at operating temps no matter where you are. So it's only a problem in moist climates I'd assume.