Frontier pickup belly pan project

[BamZipPow]

Looks like yer making good progress! Be sure to study yer work and do more brainstorming/thinking before progressing on. It can keep yer costs down and provide less waste in materials.

I set goals fer my belly pan...

Allow fer easy installation/removal of the belly pan when maintenance is required
3 segmented sections to allow fer access
Rigid frame to allow fer sectional panels
No additional holes in the frame or body (use existing holes/frame/supports)
Ability to return to stock configuration quickly

The addition of the aluminum flashing on top of the belly pan (under the exhaust system) has eliminated melting/distortion of the Coroplast. However, it's also reflecting heat back on to the floor pan. I have to add some aluminum flashing on there to make a heat tunnel...

[JRMichler]

Originally Posted by BamZipPow

Be sure to study yer work and do more brainstorming/thinking before progressing on.

Amazing how this looks like drinking beer.....

[kach22i]

My custom chin spoiler is higher than about 75% of the bumper blocks out there, and does not catch the snow on the road, no matter how much has fallen. I really think for the effort given, that it is your best deal.

Chin Spolier - fast/easy/cheap/effective - Pelican Parts Technical BBS

I've sent the same link to a gentleman which drives a 1998 electric Ford Ranger, bet he extends his range some if he does one.

It saves me about 3 mpg on the highway.

[graydonengineering]

Last night I installed a full sheet just behind the skid plate. I now have the front 2/3 of the truck done. Now all I need to do is take care of the back and rear wheel wells. I attached to any low hanging frame member that was handy and cut an access hole for oil changes. I still need to add a bit more clearance around the cat before I drive it.

The parking brake cable attachment point is the lowest part on the truck (other than the cat) so I cut a hole in my pan and made a bracket to attach through the frame here. You can see it in the center of the second pic.




I used self tapping sheet metal screws into the frame members everywhere else.




Time for a test drive. I'm interested to see how it sounds and how the engine temp is affected since the motor no longer has open road bellow it.

[graydonengineering]

Drive impressions and results:

First impressions:
I drove to work with the 2/3 belly pan and boy o boy and I a fan! The truck was very willing to accelerate to 75 on the freeway which was never the case before. Once I got up to 70, I was able to maintain 33 mpg. Previously I would have to maintain about 50% thottle for that speed and I would be around 26 mpg. The truck is quieter and has much better throttle response at freeway speed. The engine bay is now boxed off from below and the engine noise heard with the window open is significantly less.


Results:
This morning I set a new mpg record into work, 33.0 which is 1 mpg over my record and 3 mpg over my average. My previous record was set by driving behind a semi, this time around I was solo the entire time. I also now need to adjust my coast down points as I found myself using the breaks way more then usual. Once I get used to the new driving characteristics, I expect I can hit a 35 average on this same rout.

Conclusion: It's too early to calculate the net improvement. That will take a month or two. I can say with certainty that MPG improvment is there and the belly pan seems to be worth the effort, especially since my truck is only 140 hp. I can use all the help I can get to keep up with traffic.

[graydonengineering]

I am plannning on working on the rear axle area today. Right now, the center section ends in mid air about 20" in front of the rear axle. Due to the 2" lowering blocks, the bottom of the axle is about flush with mid sheet I already installed. The Diff drops down an aditional 3 inches from there. I would like to make a smooth transition without limiting axle movement. As such, I will probably mount a second directly onto the axle and try to taper the back side of the diff. Then I will have a bit of overlap from the front section to the axle section and from the back section to the axle section. Maybe I need some type of spring to keep each section tight through the axle travel. Ideas?

My question is, has anyone seen this done before? I am not 100% sure yet how I will mount to the axle. Maybe hose clampsThis is a different approch than the t-100 done by bamzippow as I trying to maintain the origonal ground clearance of the truck of about 6" or less as it is but provide a smooth bottom. Would a taper on the front of the diff do me any good?

[TheEnemy]

I was looking at axle trusses for my Jeep to give the axle a little bit of taper, but thats quite a bit of weight. The bonus to trusses for me is it also strenthens the axle.

On my Frontier I was figuring on just a lip on the front pannel to divert most of the air arround the axle, and another panel behind it that is rounded and cover all but a round hole for the spare tire, boxing in that section back to the bumper.

[TheEnemy]

Are you still using the mechanical fan?

You are making me feel bad for not getting much done on mine yet.

[graydonengineering]

Originally Posted by TheEnemy

Are you still using the mechanical fan?

You are making me feel bad for not getting much done on mine yet.

This project has been a lot of work BUT I still think it has been well worth the effort. I think so far if you skip the bumper light shaving I have spent about 30 hours on it. Lots of taking the wheels off and fighting with the self tapping screws to get them through. I have lost a bit of steam on the project but my MPG's are so much improved after installing the main section I am motivated now to finsh it off. I also have a lot of planned mods to the truck and I refuse to leave a job un-done.. Must finish!

Yes, I am using the good ol' clutch fan. I Have you changed to electric? What fan did you use and what results did you get? I am very reluctant to run an aftermarket electric fan for relyability fears. I would be inclined to pull one from a wrecked Maxima but I am not sure what type fo controller that would use and if I would need to get an aftermarket one anyway. It's genearally the controllers that cause issues. May be installation error.

[graydonengineering]

Ugg, I spent all night making a custom bracket to hang off my tail pipe and mounting a section of aluminum angle to my front leaf spring frame pivot mounts... On the plus side I think I have a very nice idea for getting over the axle seamlessly involving some springs and a bit of "service loop" of chloroplast warped around the rear axle to allow for vertical axle travel while maintaining zero gap between the front and back transition. Time will tell if the idea will actually work. It looks good in my head lol. I have high hopes for it!

Design work 10 hours a day plus ecomodds at night is wearing me thin but I am so close it's hard to put the breaks on this project. I hit 35 MPG average on the way to work this morning for 15 miles city/highway and I know I can do even better once this is done!