Jande063

This may seem like a strange question, but is it normal for these engines to have a throttle off delay where lifting from throttle input results in a delay where the engine will still accelerate for about .75-1.00 second before leveling and beginning to decelerate(it feels like the throttle body is still wide open with pedal fully off, so maybe just delay in the electronic throttle body)? Is this normal, and if so, will a tune help sharpen up my throttle releases(I autocross, so release response is important to me)?

MustangInTexas

Can't say what is normal but I get the same thing. In my '13 V6, when I hit the gas hard and then let off and hit the clutch, the engine stays rev'd for what seems way too long (as you described). I have a tune and it still does that. IDK if Bama can tune that out or not.

Nuke

A tune should resolve that in addition to other driveability issues.

J7erry

I noticed that in my 13 V-6. Whenever I disengage cruise or let off the gas, it takes a bit to take effect. Don't know why.

13V6coupe

I haven't had that issue in my 2013 V6 in the 8000 miles before or the 3000 miles after the tune.
I let off the gas/shut off cruise and the revs drop/car slows in or out of gear

WindyMustang

Ditto...but I will say that this engine as a LOT more "flywheel effect" than the V8s I'm used to driving. That is to say, once revved it wants to stay revved. It's a not a good or bad thing, just different.

MustangInTexas

I think that's kinda what we're talking about. It stays revved up for too long after you let off the gas. I guess I'm comparing it to older direct link accelerators that when you let off, the revs come right down. I hate revving way up and then need to push in the clutch and have the motor stay revved way up for a bit. Maybe I just need to learn to use the clutch differently but that still wouldn't make it right.

audioAl

I too have this situation, I am buying a tuner soon to stop it.

MustangInTexas

My basic Bama tune didn't stop it. I suppose if you request they work on that issue, it would work a lot better. Let us know.

WindyMustang

Folks, this is kind of a mechanical issue. We can mask it a bit with the tune, but it doesn't really change the mechanical physics issues. We could think about in on two fronts.

First, we need to think about rotating friction. That friction that we're used to is part of what lead the engines of old to drop revs the way we remember. Unfortunately, this friction also robs fuel and turns it into waste heat. All the tricks the Cyclone engine has to reduce friction help a LOT with specific fuel consumption (and therefore helps with MPG). The side effect is that the friction reduction also means that the engine isn't going to spin down as quickly, because there's not friction to slow it back down when there's no energy input (read: we're off the gas).

Second, we need to think about the losses due to pumping action. During the intake and exhaust strokes the engine is more like an air compressor. When there are big restrictions in getting the "air" in or out of the engine, there's force against the piston and that slows the engine down (assuming we're off the gas). The Cyclone engine was heavily optimized on it's intake side, so that the "resistance" to sucking in the air is lower and therefore doesn't consume as much energy. Yeah! But it does mean that there's less drag on the motor so it wants to keep spinning. We could debate how well the exhaust side is optimized...for the most part the crappy headers we have are going to provide more resistance than they should.

The third factor would be related to the choice of flywheel. I suspect this engine has a relatively heavy (for its displacement) flywheel, so probably more inertia there too. Does anyone know the weight of the stock flywheel? It might be interesting to see how a Cyclone performs with an aluminum flywheel (if it doesn't already have one)....