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This was brought up in the thread linked by micro, but if you're going to dyno a Focus, at least if it's a ZX3 [donno if the gearing is different], use THIRD, not Fourth.
 

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4th is the closest to a 1:1 ratio, which is why it's used. But from what I can see, 3rd is closer to that in my Focus. *shrugs* I haven't looked up the actual ratios, I could be wrong.
 

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Focal... did you read that thread? You do it in 3rd because... well just look at the graph man.... speed governor...
 

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speed governer .... I'm guessing ...

In 3rd gear @ 7k I would prolly be doing 105ish see as I get about 15mph per 1k rpm in 3rd.

When I drive, I have noticed the rpm:mph are like this:

1st 1k:5mph
2nd 1k:10mph
3rd 1k:15mph
4th 1k:20mph

not exactly, but its pretty close.
 

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Discussion Starter · #14 ·
4th gear is direct drive or a 1:1 ratio, as close as your going to get.

The purpose is to start the dyno run as low in the rpm as you can. Running your car in 3rd gear is cheating yourself and giving a false reading.

Again I have dyno'd my car over 40 times alone, please don't question me on this.

If you insist, call turbotom and ask him, he owns a dyno shop and will be happy to corroborate what I am saying.
 

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So I thought it pulls timing after 100 then the fuel cut happens at 105, how exactly are you supposed to get a reading in 4th since you can't get to the rev limiter?
 

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Discussion Starter · #16 ·
eggyolk said:
So I thought it pulls timing after 100 then the fuel cut happens at 105, how exactly are you supposed to get a reading in 4th since you can't get to the rev limiter?
Not sure where you got that info, is this PZEV specific? Every focus I have dyno'd has been in 4th and never had a problem.
 

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Focaltech it seems you are a Zetec guy snd not a Duratec guy you need to do a little more homework on this engine before you make false assumptions. This duratec has a totally different computer than a Zetec and if you run you dyno pull in fourth gear the closer you get to 100mph the computer starts yanking out timing then eventually cutting off the fuel. You have to dyno a Duratec in 3rd and I dont know about the false reading claims, because when you dyno a stock one "in third" it puts out what its supposed to at the wheels 126-128aw.
 

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Discussion Starter · #18 ·
Well the problem with doing it in third depends on the transmission. See thats why they are normally done in 4th. The 1:1 ratio provides the best account of actual power making it to the wheels.

The only way you can see that it is "supposed" to make 126-128 is by the dynos you have seen. We don't know if these #'s are 100% correct.

I also cannot understand cutting fuel and timing under 100 mph, umm if this is true, that seems retarded.

I am trying to find somethings out now from ford, hopefully I will have some new info soon.
 

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Discussion Starter · #20 ·
If the gear ratios are different it could make sense to do it in third gear. The thing is to have a 1:1 ratio in third would make 5th umm just like non existant.

I am trying to find out the indepent transaxle gears, when I have those #'s it will be better explained.
 
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