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Discussion Starter #1
Anyone notice how their car goes into an engine braking mode when they coast in gear?

What I think is happening, after 1 or 2 seconds after going to zero throttle position and as long as the engine speed is under 1500 RPM, an engine mode is activated which minimizes fuel delivery for economy. That means two things: 1) the momentum of the car fully sustains the engine and 2) the car is burning next to nothing in terms of fuel, much less then idle.

This is very noticable going down steep hills. Normally you would have to downshift to an extremely low gear or apply the brake to slow your decent down the incline, but in the SVTF the engine braking is enough to slow the car even in 6th gear.

I've applied this theory to achieve optimal fuel economy by coasting as much as possible, espeacially going down hill or into stop signs and lights. I would do this anyway, but because of this engine braking mode the engine slows the car much more then I am acustomed too.

Any comments?
 

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Pretty much all cars do this. Make sure ya rev match ur downshifts though because the clutch will take a hug beating if ya dont and the svt isnt the car to strain the clutch on.
 

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Discussion Starter #3
Pretty much all cars do this. Make sure ya rev match ur downshifts though because the clutch will take a hug beating if ya dont and the svt isnt the car to strain the clutch on.

I always rev match. I can do it without using the clutch.
 

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all grown up
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my svt braked hard when i downshifted...my honda doesn't slow down as hard when i downshift...it's probably a matter of weight. SVT weighs only 2700 lbs, honda weighs a stout 3300 lbs.
 

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damn is that weight for real thats suprising
 

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I always rev match. I can do it without using the clutch.

Clutchless downshifting. Not the greatest idea with syncos. I would rather replace a clutch than a synconizer. If ya use the clutch it will be much easier on the transmission. big rigs you can drive like that because they have straight cut gears and no syncros. Its up to you but its hella easier on the transmission and your wallet to use the clutch on a downshift. Upshifts without a clutch are easier on the trans because the sycros arent fighting the weight of the car and momentum. Just the weight of the flywheel for the most part. And its more noticed because of the higher compression of the SVT engine vs. the honda engine.
 

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Discussion Starter #9
Clutchless downshifting. Not the greatest idea with syncos. I would rather replace a clutch than a synconizer. If ya use the clutch it will be much easier on the transmission. big rigs you can drive like that because they have straight cut gears and no syncros. Its up to you but its hella easier on the transmission and your wallet to use the clutch on a downshift. Upshifts without a clutch are easier on the trans because the sycros arent fighting the weight of the car and momentum. Just the weight of the flywheel for the most part. And its more noticed because of the higher compression of the SVT engine vs. the honda engine.
I was hoping someone would call me out on that. I'm aware of the abuse it causes to the synchros, 99.9% of the time I use the clutch. But on a quick 4th to 3rd down-shift it can be fun.

On a racing gear box with straight cut gears with dog rings it's the proper way to shift.
 

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Its easy to downshift quickly with the clutch. This is all done is quick succesion. Push in clutch, rev motor, shift down, release clutch, floor it. Then there is no hurting anything. And when I mean quick, like within a second. Almost done all at once.
 

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Discussion Starter #12

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Obama Can't Gymkhana
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I rev match and DownShift all the time to brake.. Of course I use the Clutch.
 

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I always rev match. I can do it without using the clutch.

Clutchless downshifting. Not the greatest idea with syncos. I would rather replace a clutch than a synconizer. If ya use the clutch it will be much easier on the transmission. big rigs you can drive like that because they have straight cut gears and no syncros. Its up to you but its hella easier on the transmission and your wallet to use the clutch on a downshift. Upshifts without a clutch are easier on the trans because the sycros arent fighting the weight of the car and momentum. Just the weight of the flywheel for the most part. And its more noticed because of the higher compression of the SVT engine vs. the honda engine.
 

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all grown up
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Clutchless downshifting. Not the greatest idea with syncos. I would rather replace a clutch than a synconizer. If ya use the clutch it will be much easier on the transmission. big rigs you can drive like that because they have straight cut gears and no syncros. Its up to you but its hella easier on the transmission and your wallet to use the clutch on a downshift. Upshifts without a clutch are easier on the trans because the sycros arent fighting the weight of the car and momentum. Just the weight of the flywheel for the most part. And its more noticed because of the higher compression of the SVT engine vs. the honda engine.
10.2/1 vs. 10.0/1 compression ratio shouldn't make a difference...maybe it is just the flywheel. Either way USE YOUR CLUTCH...clutches are damn expensive now adays.
 
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