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Old 07-19-2019, 05:00 PM   #41
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SANDDOG's Avatar
Brand: Thor Motor Coach
Model: 2017 Miramar 34.2
State: California
Posts: 133
THOR #14761
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Originally Posted by gmtech16450yz View Post
Couple quick points here...

On smog laws and these specific aftermarket tunes...

1-New vehicles in California have 8 YEARS before you'll need a smog. That's a long time.
2- If your GVWR is below 14,000, you'd be getting a BAR OIS test, which (at this time, this is changing though) doesn't know or doesn't care what the exact calibrations (CVN numbers) are during the smog test. In other words, as long as there are no codes and the needed monitors are run, you WILL pass smog with any of these particular aftermarket tunes in these particular vehicles. If you're over 14,000 GVWR, then you'd be getting a BAR 97 test (2 speed dyno), which again, as long as there are no codes, monitors have run and the aftermarket tune isn't totally butchered, you should pass even the dyno test just fine.
3- Any of these aftermarket tunes can be put back to totally stock calibrations in a matter of less than 5 minutes. So if you do need a smog, you simply load the stock tune, drive it for a few days and go get your smog done.

On trans downshifting, running rpms and gas mileage...

There's a reason why Ford drops the 6 speed from 6th to 4th really easily. Both 5th and 6th gears are overdrives. You REALLY don't want to be putting a whole lot of load on overdrive gears. So dropping from 6th to 4th most of the time is actually the right way to climb a grade, ESPECIALLY when towing.

Technically, the highest efficiency in an engine is at the lowest rpm and the widest throttle opening for the given load. I say technically because that's in a lab with 100 other variables taken out of the equation. It's basically when the engine's pumping losses are the lowest. In reality, it has to do with all those other variables, like how the engine calibration is written, how the engine itself is built (intake and exhaust runner design and sizes, compression ratios, bore/stroke, cam timing and profile, etc, etc,). I've got about 8,000 miles of data on my V10 already, I log about 30 engine PID's every time I drive. Fun fact- you actually CAN get better gas mileage at 2500rpms vs 2000rpms in the right conditions with the way these V10's are built. It's not all cut-and-dry, there's a lot to this stuff. The worst part for us with the V10? That it doesn't have VVT. If it had variable cam timing tuning would make an even bigger difference in gas mileage and torque. (That's something that makes the new Ford engine so exciting, it has VVT.)
Hey GMtech - I for one appreciate everything you wrote here and makes total sense and I understand it thank you for your input

Miramar 2017 34.2, roadmaster front & rear sway bars, sumo shock, Roadmaster stabilizer bar, Koni shocks, F150 crewcab coyote motor , 2004 40th #26th edition 911, E350 2 door coupe, Mini Paceman 2013 6 speed manual toad/ RV
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Old 07-19-2019, 07:18 PM   #42
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Brand: Thor Motor Coach
Model: Vegas 24.1
State: Florida
Posts: 583
THOR #5313
The only time I have seen over 4,200 was in Blue Ridge. It calmed down by using more brakes. On hills it never has gone higher than 3400 to 3500. I do not use cruise control on inclines. The factory tune seems conservative. I do not like to lug motors and would rather drop a gear or two.

There is one small incline on 70 east of Lake Placid that will make it drop a gear or two at 55 MPH or less. If I hit it above 60 MPH no downshift at all.

I have yet to run into a situation that v10/6 speed stumbles with in 24,000 miles. If I do then will call 5 star.

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Old 09-11-2019, 08:21 PM   #43
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Brand: Thor Motor Coach
Model: 32.1 ACE
State: Texas
Posts: 127
THOR #14323
I have the worst luck using "search this forum", I tried finding one of my previous posts about tuning, nada.

I did the 5 Star earlier this year, just bought MH in Jan 2019, power & shifting was much improved. On one long trip the check engine light kept coming on. I researched it & it seems P0300 (I think was the #) seemed rather generic & nothing serious. On the trip back home it happened once or twice early in the trip, to never return.

Once home I called 5 Star & told them what happened, I asked them to look at my program to see if it might have a small error & it never happened with stock tune. I was told to take it to Ford, I did, everything OK. I went back to stock tune b4 going to Ford.

I took a few other short trips after putting 5 Star tune back in. No issues.

I saw on one of the threads where Brazel Ultra tune was offering a tune to compare at a very good price, if you had the correct device.

First impression was Ultra was smoother, just felt good, can't describe, it just felt like it was running better. The low end power, maybe 1st & 2nd, was not quite as strong as 5 Star. Mileage was 1-2 tenths better, according to my scan gauge. Only change was and oil change at 4700 miles & DW added a few more of her must have items.

I've got another short trip to Dallas/Ft Worth area, this month & next month from Texas-Arkansas-Mississippi-Georgia & Florida. If any thing changes good or bad, I'll post my impressions. I felt like I owed feedback since Brazels gave me a chance to compare without spending big $'s.
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Old 09-11-2019, 08:46 PM   #44
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Brand: Thor Motor Coach
Model: 2018 24.1 AXISSIXxSIX
State: Arizona
Posts: 3,130
THOR #13932
About that 60 seconds pedal to the floor setting:
I was climbing a hill outside of lukachuki on the Arizona side of the Navajo reservation. Paved road so steep I thought I might have to use the low gear in 4x4 due to a hairpin turn in the middle of a 22%+- grade.
I was able for the first time to actually floor it for 60 seconds.
Holy crap!
The roar from the exhaust and engine was like a gasser at a tractor pull and it picked up about 15mph in about 3 seconds.
I may get a tune just to have that 60 seconds changed to 15 seconds.
It... Was... Astounding.

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