Engine doesn't seem free revving
 

My 09 370Z with 7800 miles and manual trans doesn't seem to be as free revving as I'd like. My daily driver is an 06 Honda Element with a 2.4 ltr four cylinder engine and a manual trans, it has 58,000 miles on it.

When I rev the Honda from idle or any other rpm it responds quickly and willingly. The 370Z on the other hand is slower to rev and seems to be held back somewhat.

Would this be normal when comparing a high powered V6 to a much less powerful 4 cylinder, or will the Nissan rev more quickly as the mileage adds up and engine loosens up a bit?

Or perhaps, the 370Z has a larger, heavier flywheel that will never allow it to be as responsive as the much smaller Honda engine.

Of course, in normal driving and especially when merging onto the highway the
370Z gets me up to speed in a hurry.

If you are revving in Neutral there is a lock of sorts so that you won't over rev the engine.

Yes, I am revving in neutral at a stand still, and I have noticed that there is a rev limit of about 4500 rpm when in neutral and a no load condition. No doubt this is a good thing.

I suppose, what I may be experiencing is this rev limiter in action. Although, I will say that when blipping the throttle for a down shift I would like a quicker response.

Blipping the throttle for a down shift is a new thing for me so, perhaps, it's just an adjustment on my part that's needed.

No, the Z is ungodly slow to respond. It's partly the heavy flywheel and the partly the electronic throttle. I'm looking into the Speed Booster which improves throttle response as a possible solution.

Alex, can you tell us more about the speed booster?

A lightened flywheel and crank pulley helps a lot with the lazy revving.

same here lighter pulley and flywheel helped alot, except for the noise

I need to fix this issue. It makes the engine feel very much un-refined and lazy like you said.

[QUOTE=RCZ;699481]Alex, can you tell us more about the speed booster?

I found out this product is called the "Sprint Booster" and it attaches to your gas pedal. There are a couple of install videos on You Tube. It looks real easy to install and is pricey at $329 for something so simple, but it's probably well worth the cost if it's built to last the life of the vehicle.

I want to get this product, but dang it, why is everything I want so costly?
WHY DO I ALWAYS HAVE TO SUFFER?

^ if it does what it says, $329 is cheap..

At that price, could a similar effect be built in to a tune?

Accelerator by wire technology is still lacking imho.

That and a massively heavy flywheel.

I hear the UpRev tune gets rid of the throttle lag a lot of guys speak of. Think that may help????

Mustangs, 'vettes, etc. I have talked to the owners of after a tune always say a good tune fixes the issue.

I emailed the speed booster folks and I'm working out either a free demo or a 30 day trial with money back guarantee. I'll post something as soon as I know more. Hopefully it helps response rather than just make the throttle a hair-trigger on/off switch.

NST Pulleys do help in this department :tup::tup:

I actually have the sprint booster in my 335 BMW coupe. The car's an automatic, and it helped immensely. I used to get so annoyed when passing in normal drive, that I found myself always using the sport mode and paddle shifters.

So in normal Automatic mode, it actually works by reducing the lag a lot. I'm not referring to the turbo lag, that's still there. It's not bad, but the two together in normal auto make the car sluggish when passing.


That's the good, the bad, is your fuel economy drops. *Not just me but a friend has it in VW GTI, and another in his 550 bmw.

Don't ask me why, but since I installed it, I lost about 2mpg. I used to get a combined 24.3 in that car. Now I get 21.8-22.2mpg. Same driving style, same shift points, same roads etc. I'm not sure what changed. All I can think of is that it revs sooner, and holds the rpms up which in turn burns more fuel??

Also, when the car's in sport mode using the paddle shifters, i can't tell a difference at all.

Which in theory leads me to believe the ecu runs a different map or something in sport mode on the BMW. Changing the pedal response and shift points.

Now with my Nismo and a 6spd, I think it would be wasted money.
But if you have a auto trans, its worth it.

YMMV....

I had the sprint booster intalled on my RX-8. It had a button that let you change how reposive you wanted the throttle to be. From normal to aggressive. It works to a degree, but it won't make the car any faster or free revving. Cuts maybe a few milliseconds off since it's already sending a signal before your foot goes down or something about the voltage. I can't remember which. I personally don't think the Z really needs it and money can be better spent elsewhere for real power gains.

I don't expect the device to increase the power, but I do want a much faster response to my right foot action. Right now, it's especially frustrating when blipping the throttle for a downshift. My Honda Element is much more responsive in this regard.

The latest version of this product offers 3 different settings. I'll probably find that the middle setting will be just fine for me.

I agree. The most aggressive setting is way too sensitive and your passangers will hate you for it. It's a pretty easy install by the way. You just remove the pedal and install the device before the harnest. Easy to take off in case you need to have warranty work done.

Sprintg Booster
 

I does what they claim I have one installed

From what I read, yes, it just makes it a hair trigger. Actual response is unchanged, you just don't have to move your foot as far to get the same response. A proper tune should eliminate these issues. $20 in parts being sold for $330 is a bit much for so little.