Okay so general SHO question..
2013 non PP with LMS stage 3 tune, why is it that sometimes this car hauls bass and other times its like the car has trouble getting its legs stretched.
Like earlier today, doing 55, a dodge caravan pulled up and the younger dude driving took off, so I punched it, and I mean I pulled away from him alright, but it wasn't like a twin turbo tuned high performance sedan walking a damn minivan pull.
And then how is it that the F150 economist makes so much more torque than our identical motor? Ford dropped the ball on the SHO.. Same ass motor in their truck, flex, and explorer.. This motor needs something different to stand out as a Super High Output option for their sedan.
Trucks have bigger turbos.
And while the motors are similar they are not he same.
The trucks are built much more stoutly on the lower half.
In it's OEM state the SHO is tuned for comfort and more importantly 'shock tolerance'. When you drop 3 gears it REALLY thinks about it and applies tons of TQ management so you don't rip the tranny's guts out at 65 by dropping 3 gears into the 5000+ rpm range with 350-ftlbs of TQ 'instantly'. So when you stomp on it with a minivan next door.. initially.. you both are making about the same Wheel TQ until the ECU decides to applly full boost, then full spark.
Tuned... well that depends on you tuner. Again even while modified a number of base tunes and canned tunes leave a lot of TQ management in place to make sure you don't go from 6th gear @ 175ftlbs to gear 3 @ 450+ftlbs for the same reason. Going balls deep without TQ management WILL lead to a drive-train failure eventually.
thing to keep very close in mind, the gm/ford hybrid 6F55 transmission is only rated to 350hp/TQ. ( https://en.wikipedia.org/wiki/GM-Ford_6-speed_automatic_transmission )
lastly .. dependant on the air density, heat, humidity your downshift may not be generating top power levels immediately
Edit :: As Glock-coma just mentioned the turbos are different (but not that much) and the exhaust is better as it is not a transverse build. both those combine for better low end TQ, and better TQ longevity which is better for moving that Brick through the air.
One small correction: there is no official capacity rating for the 6f55. But from what people have experienced over the years, 500-550 hp/tq at the crank seems a reasonable barrier to longevity in stock form.
Quote from: SHOdded on January 08, 2018, 02:00:52 PM
One small correction: there is no official capacity rating for the 6f55. But from what people have experienced over the years, 500-550 hp/tq at the crank seems a reasonable barrier to longevity in stock form.
Fair enough!
FMC has seen trans failures overvthr 700hp threshold. They wouldnt say what failed only to say it was over 700hp. 2 of the higher hp cars SHOs have had failures. BPD is still on his original trans and has run the middle track file which is 680hp at the motor.
I ran full Friday night street racing at my dragstrip with my 2012 and 2013. Had no issues. Over 200 passes on each car. They are stronger than you think. Keeping good quailty fluids and changing them more helps a lot.
As for your car car not seeming to go. You actaully get used it over time, so it may not feel as fast. You running V10 or V11?
I'm not quite certain but is a stage 3 tune a 93 octane tune ? Found using Top Tier-gas @ busy high turnover stations to be ideal for optimum performance preferably Shell-93,Chevron-93 stations! Spark Plugs gapped @ 0.030 ?
I found the original plugs to be scattered from the factory from 0.035-0.045 gap range! Z
I also think mine is very quick to learn driving habits. If I am putzing around with the family for a few days it is almost like it forgets how to be fast. Give it a few good WOT runs and it is back to full power. By full power, I think it has more to do with the timing the ECU is allowing more than anything. I can feel it and I can see the numbers if I have Torque open too. It can be annoying at times as it feels like it just let you down. The remedy is to punish it and then it wakes back up!
I also notice a little better power with Shell 93. I try to only do top tier for the detergents, but Shell is tops.