I don't know about the engine, but it makes the truck LK cler.

I also believe the "heat shield" acts as a sound deadener, as well - but I have no real proof.

 

Don't think it would with the heat shield in cause it blocks the cowl part

 

I havent had the insulation on for a couple years.

I would think if it rained really hard, and somehow water got inside the cowl opening.. it would saturate it?

Other than that, I can see heat being vented at a stoplight from the grill opening.

 

Yeah I have had it off for a while now..... Perfect..... Runs about 195-200 with the cowl compared to before at about 210.... Not much difference.. but it lookd awesome... Ill get some pics up....

 

Heres some Before and After Pics

 

Nice! Looks sweet, what color is your truck?

 

I never put mine back on, but the Goodmark hood has all the holes already in the underside for the fasteners.

 

Metallic Green....