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High Gear WOT???

Kip2MyLou

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#1
I don't know if anybody watches this guy but I do, and he owns a Eco Mustang and just found out that you can't go WOT in 6th gear. I know there's a lot of new members here everyday so I liked to bring this to their attention also. I try my best to always downshift to 5th on the highway, for this very reason. But I also like to point out the comments in the video. People are blaming it on the tune and calling the Ecoboost a terrible engine and all that BS.

https://www.youtube.com/watch?v=z5_K2P49hyw

So free feel to leave comments especially you people who do all the tech talk on here. You know who you are!!!
 


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Bristol
#2
Good Info! I wast just thinking to my self on the way home yesterday while going through an interchange that I should be using 5th gear more. I'm on the freeway a lot so it gets neglected.
 


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#3
If you're referencing LSPI(Low Speed Pre Ignition), it's been discussed ad nauseum here and elsewhere. Barring all the previous mentions, it should be common sense to not beat on your vehicle in high gear...any vehicle, let alone a high-strung high-boost small displacement engine.
 


frankiefiesta

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forked river
#4
Yes been discussed but always good to bring up for those who may not know.

I always down shift to 5th, sometimes 4th depending on how much and how quickly I need to accelerate.

If nobody else is on the road and I am just changing lanes or passing somebody slow and can take my time I don't downshift
 


JasonHaven

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#6
This is the first I've seen of this... I haven't gone WOT on the highway in 6th, but I've definitely dipped my foot into the gas to make a pass, so I'm not sure where the 'line in the sand' is in regards to safety... I'll try to remember to downshift more now, though o_O (I haven't had any issues yet)
 


GAbOS

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#8
Is it the gear or the rpm though? It sounds like low rpm wot issues. Our highway cruise speed where I am is 80 or your getting run over. That puts me above 3000 at cruising speeds.
 


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Georgetown
#9
It's any high load situation. Typically high gear + low rpms + load(I.e. Passing or climbing a steep hill). Boost comes easily in high load, and things break.
 


JasonHaven

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#10
You may not know you have issues till you have big issues. Pre ignition is no joke.
Any gauges one should look at to make sure everything is ok?

Like I said, I haven't done WOT in 6th, I generally shift down if I need to accelerate quickly to pass, but I have dipped into the gas a bit in 6th for passes that aren't as rushed, so I'm kind of wondering where the line in the sand is, and if I passed that already haha
 


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Georgetown
#11
Run good fuel, and develop good driving habits, are my best advice. I track ignition corrections in cylinders 1 & 4, specifically to watch for trouble signs...though even those monitors aren't 100% a sign of trouble.
 


GAbOS

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#14
It's any high load situation. Typically high gear + low rpms + load(I.e. Passing or climbing a steep hill). Boost comes easily in high load, and things break.
This is where I get confused. (Is my scenario above unsafe to WOT in 6th)

I understand "load" as it's loosely defined and using a vehicle at low rpm with the incorrect ratio.

What is the minimum RPM in 6th to WOT?
 


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Location
Georgetown
#15
You're thinking way too hard on this one. Simply put, don't stomp the throttle in sixth. Ever.

I've seen the way you drive. You've got a heavy foot. You'll blow yourself to piecessssssssss...
 


CanadianGuy

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Southern Ontario
#16
Thanks Kip2mylou for posting the video.

I must agree with a point from the video. [MENTION=555]COBB Tuning[/MENTION] If this is such a problem (big or small) why would the tune not limit the boost in 6th? I know it does in first. Would be an easy way to prevent stupid. Another option could be a warning feature on the accessport. Again this is not for everyone but one this is true that if this is a concern it should be better communicated to the drivers. Especially those new to the turbo cars.

As for my drive I do dip in 6th to go from 60mi/h(100km/h) to 80mi/h(130km/h) but keeping an eye of the boost it rarely goes above 7-9 psi in those situations. But I may change that to drop shift for more piece of mind and a little more fun.
 


dyn085

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Vancouver
#17
Tuners aren't going to limit boost in gears unless you ask for it specifically because it's a waste. Why limit the car if you have control over your right foot and the gear you're in?

For those that want to go WOT in sixth-just do it. It's a waste of time for the community to continue trying to explain why it's a bad idea. No one is going to tell you a specific rpm that is 'safe' for it so just pick one and roll the dice.
 


JasonHaven

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#18
I can't speak for everyone, but it's not necessarily a desire to go WOT in 6th, it's just getting a feel for what's safe and what's not. I understand it's a bit of an abstract, and it's hard to put exact numbers on, but getting a general idea helps a lot, imo.

My previous cars were naturally aspirated econo cars, so shifting down to accelerate/pass isn't anything new to me. But, having low end torque all of a sudden, I've found myself not shifting down as much, because why bother? Now I see that's a potential problem (though again, I haven't done WOT in 6th), I'll go back to shifting down to accelerate/pass if I need to do it with any aggression.
 


BoostBumps

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#19
Tuners aren't going to limit boost in gears unless you ask for it specifically because it's a waste. Why limit the car if you have control over your right foot and the gear you're in?
This might be of some interest to some...

COBB's newly released v220 OTS MAPs stages 1,2, and 3 appear to now slightly limit max boost through their "Boost by Gear" / WGDC mutliplier table for 5th and 6th gear found in switchable map section...

Here is the BBG table for stage 1 for example (which is populated by values identical to stage 2, and 3 as well)....As you can see 5th & 6th gear boost is somewhat limited by multiplying values found in this the table against those in the WGDC map (see highlighted in table below)...Part throttle boost conditions appear to be limited even further in both 5th and 6th gears...Multiplier Values of less than 1.0 will reduce max achievable boost close to the fractional multiplier amounts shown...

Boost by Gear Limiting.jpg

Description below directly taken from COBB ATR :

"WGDC Boost By Gear Multiplier

This table allows a throttle based per gear adjustment of wastegate duty cycle. This multiplier will be applied to the final WGDC after all other WGDC calculations and compensations.

Tuning Tips - A setting of 0 will eliminate WGDC at a given throttle position in the desired gear. A value of 1 will apply no correction, and a value of 1.5 would apply a 1.5 times the final wastegate amount. This can aid in preventing overboost in lower and higher gears.

Please be aware that the OEM P/I dynamics will constantly try to fight this multiplier when in use, so be sure to adjust the P-Term, I-Term, and PI-Error (Max) tables so they play nicely"
.
 


Hijinx

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Auburn, AL, USA
#20
I can't speak for everyone, but it's not necessarily a desire to go WOT in 6th, it's just getting a feel for what's safe and what's not. I understand it's a bit of an abstract, and it's hard to put exact numbers on, but getting a general idea helps a lot, imo.

My previous cars were naturally aspirated econo cars, so shifting down to accelerate/pass isn't anything new to me. But, having low end torque all of a sudden, I've found myself not shifting down as much, because why bother? Now I see that's a potential problem (though again, I haven't done WOT in 6th), I'll go back to shifting down to accelerate/pass if I need to do it with any aggression.
Here's your general warning: Just don't.
 




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