Concerned by the very high temps under the hood, I added some Gen Right hood vents. I went with just two to start with to see how they would do, and the cross bracing on the JK's hood makes it a little more tricky to add the longer ones, although it could still easily be done.
The instructions are clear and easy to follow. Obviously, the most important thing is measuring, so follow the old adage, "Think twice, cut once".
I spent a few minutes with IR thermometer looking for hot spots on the hood, and found four; Two either side of the engine, one at the rear of the engine, and one at the front between the engine and fan. You also need to give some thought to what is under the vents in terms of water intrusion, but you are kind of limited in this regard due to the cross bracing of the hood. If you have an aftermarket air intake, do make sure you will not be exposing the filter with the vent, as when it rains it may well get wet. You also need to take account of the cross bracing, and while you could work over it if you used a die grinder just to cit through the hood, you do not want to cut through the cross bracing.
I used masking tape over the area I was working to minimize scratches, etc. After tracing the outline of the vent, I marked 1/2" in and drilled four 1/2" holes in the corners. A pilot hole followed with a step drill will reduce the potential for dimpling the sheet metal. I then used a jig saw with a fine blade to cut out the areas.
Place the vents back on and position again (Think twice, cut once), and then drill the rivet holes with a 1/8" drill bit. Remove all the masking tape, remove any rough edges and paint. The vents need a little tweaking to follow the lines of the hood, but this is pretty easy. Rivet in the hood vents with the supplied rivets and you are done.
I cut some holes in the under hood insulation and replaced it, but you just as easily leave it out.
Installation took 90 minutes.
Once the engine is up to temp there is 150-160°F air coming out of the vents. I have no real way of knowing how much cooler it is under the hood, but it is definitely cooler, and I'd say there is more air flow. You don't get hit by such a blast of hot air when opening the hood, and air intake temps have dropped by between 5-10°F on the highway.
On a wheeling trip over the weekend, I didn't see intake temps go much above 130°F, with an ambient air temp of 100-105°F. Previously they would get up to 150°F or so. This indicates to me that under hood temps are definitely cooler than before by a noticeable amount.
I haven't had a chance to see how much water intrusion there will be when it rains yet, but when I washed it there was not as much water intrusion as i would have expected. On the highway, water intrusion is unlikely to be an issue, but for those in wetter climes that leave their vehicle outside it is something to think about, although I suspect it will be minimal.
I didn't get a chance to take pics as I did the work, but here's some after shots, which give you a pretty good idea.
The instructions are clear and easy to follow. Obviously, the most important thing is measuring, so follow the old adage, "Think twice, cut once".
I spent a few minutes with IR thermometer looking for hot spots on the hood, and found four; Two either side of the engine, one at the rear of the engine, and one at the front between the engine and fan. You also need to give some thought to what is under the vents in terms of water intrusion, but you are kind of limited in this regard due to the cross bracing of the hood. If you have an aftermarket air intake, do make sure you will not be exposing the filter with the vent, as when it rains it may well get wet. You also need to take account of the cross bracing, and while you could work over it if you used a die grinder just to cit through the hood, you do not want to cut through the cross bracing.
I used masking tape over the area I was working to minimize scratches, etc. After tracing the outline of the vent, I marked 1/2" in and drilled four 1/2" holes in the corners. A pilot hole followed with a step drill will reduce the potential for dimpling the sheet metal. I then used a jig saw with a fine blade to cut out the areas.
Place the vents back on and position again (Think twice, cut once), and then drill the rivet holes with a 1/8" drill bit. Remove all the masking tape, remove any rough edges and paint. The vents need a little tweaking to follow the lines of the hood, but this is pretty easy. Rivet in the hood vents with the supplied rivets and you are done.
I cut some holes in the under hood insulation and replaced it, but you just as easily leave it out.
Installation took 90 minutes.
Once the engine is up to temp there is 150-160°F air coming out of the vents. I have no real way of knowing how much cooler it is under the hood, but it is definitely cooler, and I'd say there is more air flow. You don't get hit by such a blast of hot air when opening the hood, and air intake temps have dropped by between 5-10°F on the highway.
On a wheeling trip over the weekend, I didn't see intake temps go much above 130°F, with an ambient air temp of 100-105°F. Previously they would get up to 150°F or so. This indicates to me that under hood temps are definitely cooler than before by a noticeable amount.
I haven't had a chance to see how much water intrusion there will be when it rains yet, but when I washed it there was not as much water intrusion as i would have expected. On the highway, water intrusion is unlikely to be an issue, but for those in wetter climes that leave their vehicle outside it is something to think about, although I suspect it will be minimal.
I didn't get a chance to take pics as I did the work, but here's some after shots, which give you a pretty good idea.




