Frontier pickup belly pan project

[TheEnemy]

Originally Posted by graydonengineering

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.

I have the fans from Ebay (2500cfm pusher/puller) and controls to do 3 of my cars, or to double up on the pickup. The fan is finally installed on the Jeep as a pusher, I just need to wire it up. It still has the mechanical until I get the fan wired.

Fan Switches, Thermal - Cooling & Heating - SummitRacing.com

All they are is a thermal switch and relay, pretty simple really.

On the Jeep to mount the thermal switch I got a muffler shop to weld a piece of 1/2 ID threaded steel coupler to an appropriate sized piece of exaust pipe to fit inside the return hose so that it would get a good reading. I also put an aftermarket temperature guage on the same pipe. It gets a pretty good reading.

There is another type that straps to the radiator, that one might be easier to install.


Edit to add:

On the Jeep even in 4th at 70 the engine doesn't spin much more than 2000 rpm, and 5th at 75 is arround 1600rpm but I have to downshift when I'm not going down hill. I'm not expecting much of an improvement because of how low the rpm is, but on it I'm wanting more power/torque to the wheels. The other two (pickup/ 66 mustang) spin 3000 rpm at 75, and I'm hoping that I get a pretty good improvement.

[graydonengineering]

I got past the rear axle last night. I am going to use an overlap and more bungee cord so i will have a slide joint that allows for vertical axle movement without disrupting the air flow. I also had to vent under the engine as the firewall was getting too hot and cooking my feet on a recent drive that was well over 100 degrees. the intake temp is now 15 to 40 degrees over the outside temperature depending on speed.

[aerohead]

I was looking at the Ferrari 599XX race car.They've done essentially what you've done with the soffet vents,bringing the air outside the bellypan and then they suck it back into the diffuser and blow it out where the taillights would be on a road car.
It's got to help with the firewall temps.
Nice work.Love the bungee cord!

[graydonengineering]

Originally Posted by aerohead

I was looking at the Ferrari 599XX race car.They've done essentially what you've done with the soffet vents,bringing the air outside the bellypan and then they suck it back into the diffuser and blow it out where the taillights would be on a road car.
It's got to help with the firewall temps.
Nice work.Love the bungee cord!

I have noticed that but I never realized what it was for, now it makes a bit more sense. The vent I added in the pan and a fairly small hole in the driver side wheel well of about 4" squared are the only places for air to get out at the rear of the engine compartment. It would be great if the vent creates an up draft allowing more hot air to be sucked into the intake. I will be checking my intake temps and see how it goes. The intake temps have run very high which may account for part of my mpg gains so far and I don't want to loose that. May have to play around with that a bit more.

I am very close to being done with the belly pan! I should finish net week. Still need to finish the rear wheel wells an put up some vertical material next to the leaf springs to smooth the flow further. After that, I will move on to whatever I expect might give me the best gains with the lease effort. Maybe some clear lexan rear wheel well skirts. I was thinking of using lexan angle and some clear plastic fasteners... Try to make them as invisible as possible.

[graydonengineering]

I put in the last major section tonight, from the rear axle to the rear bumper. It needs some refinement still. I would say the whole job is about 80% done. I look forward to a new commute average!

[Ford Man]

I just looked at your gas log and it looks like your hard work is paying off, broke 30 MPG on that last tank. Good work!!

[graydonengineering]

Originally Posted by Ford Man

I just looked at your gas log and it looks like your hard work is paying off, broke 30 MPG on that last tank. Good work!!

Thanks! I have been able to average 30 or better on my drive to work which is 6+ mpg over what I used to get before I discovered this forum. That's a 20% increase as a result of my combined mod efforts and driving method improvement thus far! 30 MPG was my original goal and I was able to hit that with less effort than expected. I guess I have to move the bar now so my new goal is 50% over EPA (33mpg). With higher gearing I think I would be there already. Next set of tires I guess!

[TheEnemy]

I have 235 75 r15's (29X9.5") on mine, they are mild AT's. The only problem is that on hard turns the front tires rub a little. If you go narrower for the same height you shouldn't have any rubbing problem.

[graydonengineering]

I am happy to report, the vent I installed under the engine did provide enough cooling to eliminate the hot firewall problem I had before at 100 degree plus temps. I did fine that the increase intake temp did seem to lead to pre-detonation and poor engine performance and my mpg. I checked my plugs wires and distributor and everything seemed fine. I filled the current take with midgrade and the performance is back to what I am used to and my trip mpg’s came back up. I can probably switch back to regular once the hot summer is over.

I put in some time on boxing off the rear wheel well today and the rear belly ban section is not living up to it’s potential with open exposure from the sides. So far I am finishing up my 3rd full sheet of chloroplast. Looks like it will take about 3.5 sheets by the time I am done.



I had to slot the section for a hose so I added a small section of material after install to reduce drag and add rigidity:



Back on the ground, bottom edges trimmed:

[graydonengineering]

The wheel well test drive was a sucess! On my 15 mile drive to work I was able to hit a new record for 1 way mpg at 35.4! I was able to glide very nice long distances. Boxing off the wheel wells and leaf springs smeeds to have really brought everything together. I still need to do the other side.