CMAX Grill Cover Testing, 2-5 MPG Gain

[fbov]

Scan Gauge is a stand-alone device. For about $20, you can get a OBDII diagnostic plug-in with WiFi or BT, and interface it with your smart phone (Torque app is $5) or Nook like one poster here did. I find it real easy to use Torque, but I've not yet gotten everything synced and seen internal engine data... maybe when it warms up... it will warm up, right?

 

HAve fun,

Frank

[ptjones]

I hate to tie up my smart phone and may eventually look for something that has even more info on the screen. :) 

 

Paul 

[ptjones]

Filled up 3/26   50.8mpg, 640mi , 390mi EV and 12.6gal. About 50% City and oil pan heater makes a significant difference between using it and not on 5 mile trips or less. Temps are moving up a little bit improving MPG's as expected. Got Fuelly back to 45mpg and Smart Gauge Life time to 46.1mpg.  At this rate should be approaching 58-60mpg per tank by Summer. :)

 

Paul

Edited April 4, 2014 by ptjones

[ptjones]

Now with temps consistently in 70's-low 80's MPG's are going up. Still have full Grill Covers on MADMAX and only takes 1/2mile for WT to reach 128*F, still takes 15-20min. to get to 200*F WT in city driving.  4/10/14 made filled up at BJ's, 656.2mi.,13.04gal and 50.3MPG w/50% city. I added Chevron Techron Injector Cleaner ,because I have 53k miles on odometer, figured it was time to clean injectors. Immediately my MPG's went down about 2mpg's, how bazaar! I filled up at BJ's on 4/19/14, 662.2mi.,13.7gal and 48.3MPG with 50% city. I did have a little more carrying my bike around on the back of MADMAX than usual, but not that much. With 250mi on this tank I really bounced back with currently 55.6mpg which means probably 54mpg actual. I'm surprised that gas additive would hurt MPG's that much when it is in the tank. It looks like my average MPG's this summer are going to be up 5mpg maybe more than last year. :shift:  :) 

 

Paul 

[Jus-A-CMax]

The grill covers are not working for the long grades & steep grades. I drove to Las Vegas this week and on the Cajone Pass, it triggered the overheat. Woo..wee. Lucky I kept an eye on temp gauge in MyView so I slowed down and pulled into the truck lane but it was DARN EMBARASSING to go at 40mph & at 2000rpm for the climb up, slower than the trucks! Then later on the same trip, the long grade past Baker to Mt Holloran(?) it again peaked...and again, back down to the 40s and truck lane.

 

Finally I had it with the covers and stopped at a rest area to pulled off the main grill cover but left the bottom one on and temps were normal in the grade climb. Yah!.

 

Got to Vegas with 48.2MPGs and except for the traffic on the 210, I15 and the over heat, made it under 4 hrs 40something and 65-70mph.

 

On this trip, I had the AC on (thanks wifey) and the outside temp was around 75-80F.

 

So the moral of the story is that for long trips where there are mountains & long grades, forgetabout-my-covers. It just ain't worth it and as I said, embarassing to be slower than the trucks up these grades while I wait for the engine to cool. I might drill some holes to let in some air in like what Matt did. Also, the bottom cover is not the most aero for the fit either so I will re-think that lower one. I did keep the lower one on, not an issue and I drove like that to Mammoth as well. Not sure if any MPGs are saved there.

 

Now, for city driving, these covers are the bomb. That I will keep.

 

PS Usual disclaimer, these are my cover grill and not Pauls but essentially, they are very similar. Be wary, if you intend to use these covers for long drives with mountains & long grade climbs.

 

Jus my 2c.

Edited April 27, 2014 by Jus-A-CMax

[ptjones]

The grill covers are not working for the long grades & steep grades. I drove to Las Vegas this week and on the Cajone Pass, it triggered the overheat. Woo..wee. Lucky I kept an eye on temp gauge in MyView so I slowed down and pulled into the truck lane but it was DARN EMBARASSING to go at 40mph & at 2000rpm for the climb up, slower than the trucks! Then later on the same trip, the long grade past Baker to Mt Holloran(?) it again peaked...and again, back down to the 40s and truck lane.

 

Finally I had it with the covers and stopped at a rest area to pulled off the main grill cover but left the bottom one on and temps were normal in the grade climb. Yah!.

 

Got to Vegas with 48.2MPGs and except for the traffic on the 210, I15 and the over heat, made it under 4 hrs 40something and 65-70mph.

 

On this trip, I had the AC on (thanks wifey) and the outside temp was around 75-80F.

 

So the moral of the story is that for long trips where there are mountains & long grades, forgetabout-my-covers. It just ain't worth it and as I said, embarassing to be slower than the trucks up these grades while I wait for the engine to cool. I might drill some holes to let in some air in like what Matt did. Also, the bottom cover is not the most aero for the fit either so I will re-think that lower one. I did keep the lower one on, not an issue and I drove like that to Mammoth as well. Not sure if any MPGs are saved there.

 

Now, for city driving, these covers are the bomb. That I will keep.

 

PS Usual disclaimer, these are my cover grill and not Pauls but essentially, they are very similar. Be wary, if you intend to use these covers for long drives with mountains & long grade climbs.

 

Jus my 2c.

This is why I supply a second Grill Cover with small cut over grill intake and still get areo improvement. It only take 30 sec. to go from one grill cover to the other. :shift:  I still haven't been able to get the overheating message with full cover yet.

 

Paul

Edited April 27, 2014 by ptjones

[Jus-A-CMax]

It only takes less than 5 seconds to remove the main grill on mine. Plus its only on these "once off" long distance trips with lterally 500ft to 4000ft or 7800ft climbs that these overheating warning issues come up so the new design would not be of any benefit in my world.

 

Am I the only one on this forum who lives in a state with long grades? Prolly so....

[ptjones]

I didn't realize we were turning this into a competition. LOL  It takes one second to peal off my Cover, 29 seconds to go the back of MADMAX open the hatch and rip off summer Cover off the back of back seat and install it over grill. LOL   I wish you had a ScanGauge so you could tell what temp you are getting too.  I have had many long steep grades(CA & AZ) and highest temp I have been able to get to is 240*F once.I still think the Top Mark on the WT gauge is 245*F. It is amazing how just slowing down 5-10 mph can drop WT 10-15*F.  I'm going to San Diego next weekend for a week so I will be able  to do more testing.

Today I went about 100mi. on the Atlanta Fwys going between 75-60mph and averaged 51mpg per Smart Gauge. :) :shift:

 

Paul

[hybridbear]

The grill covers are not working for the long grades & steep grades. I drove to Las Vegas this week and on the Cajone Pass, it triggered the overheat. Woo..wee. Lucky I kept an eye on temp gauge in MyView so I slowed down and pulled into the truck lane but it was DARN EMBARASSING to go at 40mph & at 2000rpm for the climb up, slower than the trucks! Then later on the same trip, the long grade past Baker to Mt Holloran(?) it again peaked...and again, back down to the 40s and truck lane.

 

Finally I had it with the covers and stopped at a rest area to pulled off the main grill cover but left the bottom one on and temps were normal in the grade climb. Yah!.

 

Got to Vegas with 48.2MPGs and except for the traffic on the 210, I15 and the over heat, made it under 4 hrs 40something and 65-70mph.

 

On this trip, I had the AC on (thanks wifey) and the outside temp was around 75-80F.

 

So the moral of the story is that for long trips where there are mountains & long grades, forgetabout-my-covers. It just ain't worth it and as I said, embarassing to be slower than the trucks up these grades while I wait for the engine to cool. I might drill some holes to let in some air in like what Matt did. Also, the bottom cover is not the most aero for the fit either so I will re-think that lower one. I did keep the lower one on, not an issue and I drove like that to Mammoth as well. Not sure if any MPGs are saved there.

 

Now, for city driving, these covers are the bomb. That I will keep.

 

PS Usual disclaimer, these are my cover grill and not Pauls but essentially, they are very similar. Be wary, if you intend to use these covers for long drives with mountains & long grade climbs.

 

Jus my 2c.

I would remove the lower one before removing the upper one. The lower opening is the one that allows air to get to the hyrid components radiator and the A/C radiator. The upper grille opening just blows air across the ICE radiator. You don't want to burn out your A/C compressor or hybrid components by overheating them.

 

Ease of removal is one reason why many FFH owners have switched to using foam pipe insulation for grille blocking instead of plastic covers. Flexibility is the other reason. As temps warm we can remove one row of foam at a time to manage temps. When temps cool we can gradually add foam one row at a time. Foam is also much cheaper than the plastic covers. Under $1 of foam pipe insulation will do the entire grille on the C-Max or FFH.

[ptjones]

I would remove the lower one before removing the upper one. The lower opening is the one that allows air to get to the hyrid components radiator and the A/C radiator. The upper grille opening just blows air across the ICE radiator. You don't want to burn out your A/C compressor or hybrid components by overheating them.

 

Ease of removal is one reason why many FFH owners have switched to using foam pipe insulation for grille blocking instead of plastic covers. Flexibility is the other reason. As temps warm we can remove one row of foam at a time to manage temps. When temps cool we can gradually add foam one row at a time. Foam is also much cheaper than the plastic covers. Under $1 of foam pipe insulation will do the entire grille on the C-Max or FFH.

hybridbear are you monitoring inverter temps? If so do you see a difference in inverter temps with cover on and off?  I do recommend  removing lower cover first, it's worth 5 degress on WT, I need to test how much of a difference it makes on A/C. I don't close off the Top Grill to the ICE compartment to allow some outside air flow around electronics and Hybrid components.  The advantage of LEXAN cover over foam is less areo drag, improved MPG's. Also my Grill Covers only take a few seconds to put on or off as compared with foam minutes and they look better too. IMO :)

 

Paul

[ptjones]

Filled up at SAM's today 13.25gal, 710.8mi. and 53.63mpg. YA :yahoo: First 700mile tank this year. My last tank I got 48.3mpg with Techron fuel injector cleaner, this tank I gained 5.3mpg over last. WOW :yahoo: and my Life Time went up another .1mpg. So it looks like the Techron Injector Cleaner works after using it.  Friday I will be driving to San Diego for a few days working and then coming back, about 5000 miles total. Will be stopping in AZ both ways. :)

 

Paul

[hybridbear]

hybridbear are you monitoring inverter temps? If so do you see a difference in inverter temps with cover on and off?  I do recommend  removing lower cover first, it's worth 5 degress on WT, I need to test how much of a difference it makes on A/C. I don't close off the Top Grill to the ICE compartment to allow some outside air flow around electronics and Hybrid components.  The advantage of LEXAN cover over foam is less areo drag, improved MPG's. Also my Grill Covers only take a few seconds to put on or off as compared with foam minutes and they look better too. IMO :)

 

Paul

I am. I have not seen an increase in temps with keeping my grille blocked as temps have warmed and thus have left my foam in. Most of our daytime highs have maxed out around 60 with overnight lows in the 30s & 40s so it isn't warm here yet. We're still running almost a month behind schedule on our spring weather.

[ptjones]

I am. I have not seen an increase in temps with keeping my grille blocked as temps have warmed and thus have left my foam in. Most of our daytime highs have maxed out around 60 with overnight lows in the 30s & 40s so it isn't warm here yet. We're still running almost a month behind schedule on our spring weather.

I'm On trip across the country and have done some testing. The lower Grill Cover is worth 15 degressF drop in WT. Strangely the low cover doesn't effect A/C very much at all. I'm suprised lower cover would lower WT so much.  I'm thinking of drilling some holes in cover to control temps better. :)

 

Paul

[ptjones]

Well I finally did it Jus! LOL AZ people know the long up hill grade going south out of Camp Verde on I17, I got the over heating Message at 247 degrees F as I was cresting the hill going 65mph, OT of 93*F. I actually hit 249*F for about 2 seconds and 5 seconds at 247*F. I had the A/C on and the temps drop very quickly when you let off the accelerator, down to 230*F in 30 seconds. Most of the time car runs cooler with A/C on because of fan running all the time. The fan is very strong and will suck the cover out of your hands when installing it with the fan on. Most of the time with the A/C on the WT is in the 190's with lower cover on and 170's with it off, so I leave it on. Also I didn't notice any significant difference with lower cover on or off with the A/C out put. I did put three 1.5" holes in lower cover to improve cooling going up long uphill climbs, but it doesn't seem to make a difference. :) 

 

Paul 

[ptjones]

I thought I would mention I got 45mpg average on my  5K mile trip to San Diego and back with A/C and strong winds. I think I would have gotten 47mpg without A/C and Winds. :happy feet: :shift:

 

Paul

[ptjones]

Just made another trip to AZ and back, about 3800mi. averaged 46mpg, 62.5mph (top speed in TX I10 of 89mph, 80mph speed limit) with A/C and wind. It looks like I'm getting 47mpg at 70mph on the FWY now and I have a few more aeromods to try out. :happy feet: :)

 

Paul

[Jus-A-CMax]

Well I finally did it Jus! LOL AZ people know the long up hill grade going south out of Camp Verde on I17, I got the over heating Message at 247 degrees F as I was cresting the hill going 65mph, OT of 93*F. I actually hit 249*F for about 2 seconds and 5 seconds at 247*F. I had the A/C on and the temps drop very quickly when you let off the accelerator, down to 230*F in 30 seconds. Most of the time car runs cooler with A/C on because of fan running all the time. The fan is very strong and will suck the cover out of your hands when installing it with the fan on. Most of the time with the A/C on the WT is in the 190's with lower cover on and 170's with it off, so I leave it on. Also I didn't notice any significant difference with lower cover on or off with the A/C out put. I did put three 1.5" holes in lower cover to improve cooling going up long uphill climbs, but it doesn't seem to make a difference. :)

 

Paul 

 

:clapping:  Ah so u jus validated Jus wasn't that crazy, speed freak long grade climbing nut job with lexan grill covers - u now have that title :lol2:

 

In jest, friend :hat_tip:

 

I did the Cajone run yesterday without the lower grill cover - and it was fine. In fact, I was climbing that grade at 63 mph eco, temps stayed in the middle, External was 73F. I think I will leave the middle cover on. Its a nice balance between saving the heat in the morning, aero efficiency. The lower grill cover is more of an air dam than a aero mod, imho so its now off permamently.

 

Drive on :shift:

[ptjones]

Friday I tried to break my MPG record for going down to Deltona,FL and back. It's about 850mi. and I got 62.7mpg on that trip and was hoping for around 70mpg, but ran out of time. I left about a hour and a half late and would have gotten there after 9:30PM which wouldn't work. Also I was getting the same MPG's as before, but was average about 2.2mph faster than last trip so the new Aero Mod's seem to be working. Front spoiler and air dams, Wheel covers and wheel well covers . Going from Pure Gas to Reg is definitely a -2mpg. OUCH!  I will have to try again when conditions are more favorable, It got up to 97*F on the trip, I had to use A/C ;) 

 

Paul 

[fordfan82]

Where do you get a grill cover from ?

[ptjones]

Where do you get a grill cover from ?

I was selling them awhile ago. I don't know if I have any left. You can PM me if you are interested. :)

 

Paul

[marshtex2]

Paul,

What is "Pure Gas" and how does it compare with "Reg"?  It is hard to see how our little ICE would return better mpg on a higher octane rated gas.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

i 

[ptjones]

Paul,

What is "Pure Gas" and how does it compare with "Reg"?  It is hard to see how our little ICE would return better mpg on a higher octane rated gas.

Pure Gas has no ethanol in it so it has more BTU's for about %5 better MPG's I see about two miles per gallon. The Octane was 89 that I last used. Premium can be up to 93 Octane, but might be 10% ethanol which raises the Octane but lower the BTU's. :)

 

Paul

Edited August 3, 2014 by ptjones

[marshtex2]

OK, gotcha.  Sure it is the BTU factor, not octane, that's making the difference.

[ptjones]

OK, gotcha.  Sure it is the BTU factor, not octane, that's making the difference.

My experience is Ethanol Free Gas(Pure Gas) gets better MPG's than Premium even though 89 vs 93 Octane. It comes down to how much Ethanol there is in Gas at the pump which they won't tell you. I can tell you I travel all over the country and some areas I get better MPG's than others. I'm assuming the amount of Ethanol in the gas is the difference. :)

 

Paul

[ptjones]

Well I tried to break my longest tank record and did by one mile on Garmin, but short by two miles on Smart Gauge, OUCH! Have new tires so Odometer is off by 1.019%.  It would have been a total waste except I found the sweat spot for best gas mileage. When I was driving through MS on SR-80 and Natchez Trace Parkway, about 150mi. I got 70.9mpg on 50mph speed limit with P & G up to 55mph and down to 40-35mph with very little traffic. As I have thought from the past going through towns and having to stop at lights and stop signs hurts your MPG's by at least 5mpg. I currently have 73.6K mi. with almost all of that with Grill Covers on and only take bottom one off if I know I'm going to have long uphill grade. I only took my lower cover off three times on my 5K trip to San Diego and back. My LifeTime MPG is up to 46.7 and Fuelly 45.8mpg. :happy feet:

 

Paul