Throttle Response: DE/HR vs VHR
 

So I'm not crazy after all! VVEL sounds like great technology. It offers great smoothness and consistency in power delivery especially for forced induction, and it pulls hard to redline. However, it appears the biggest tradeoff is throttle response. That's the one thing I really miss coming from the DE.

I had the opportunity to test drive my friend's '08 350Z, and he had a thrill of a test drive in my force-fed 370Z.

We started up the car and revved it in neutral. I barely touch the throttle in the 350Z, and it quickly revved to 2k as if it has a lightened flywheel. Since I'm not used to it, it feels a bit touchy on tip in. I don't think the 370Z can rev this quick. On for a test drive, I got in 1st and kept the revs under 2k. I tapped the throttle and literally broke loose before the revs touch 3k. This is with VDC disabled.

Of course, this is where it feels different. I opened it up a bit and expected more power beyond 3k. It's a slightly vague feeling over the 370Z (off boost), but there is still an immediate response of the accelerator pedal to the throttles.

It would be nice to have my ECU throttle tables tweaked to get this feeling back. It would make the 370Z (force-fed or not) so more fun to drive.

Have you heard of or read on here about a device called Sprint Booster? Some owners, even after forced induction claim that it helps to eliminate throttle lag.

IIRC that only increases the pedal sensitivity, not throttle lag?

I agree withe the OP, my old '05 DE 350Z had better throttle response. How much I'm not sure but that's one of the few things I miss from it.

Did the 350Z's have throttle by cable or by wire, like the 370's?

drive by wire

I guess that is the trade off of not actually using the throttle bodies and letting VVEL act as the throttle. Sometimes I like how progressive and smooth power delivery is but other times, it feels too relaxed and undramatic.

Fingers cross for a VVEL controller and that it could help out engine response!

Exactly. I believe UpRev makes available the throttle tables. I think "wstar" made a post about tweaking the table for better response, but it can get finicky.

It feels like our pedal simply provides inputs and the ECU determines how much it thinks the throttle position should be for efficiency, emissions, fuel economy, etc. Instead, we expect it to be 1:1.

It's almost like electric power steering. In my parent's '11 Sonata 2.0t, there's no confidence making turns because the steering feels numb and has a mind of its own.

definitely have noticed the same thing driving the 350s. I think part of it is in the way the 350 ECU responded, and the throttle tables, etc...but I think part of it is just the engine's nature. I think the VHR is just slow down low.

IIRC, the HR and VHR are very closely related. I think the difference is with the heads.

In theory you can advance the timing on tip in, which should give quicker response... I'm going to try experimenting with that next time assuming there's a table for it.

yeah, they are. The HR was notably slower than the DE too. I feel like the VHR was even slower than the HR, but it's hard to say...sometimes it is just in your head

I didn't get to push the HR hard, but it was enough to tell the difference in the lower revs. Although it ramps up slower, I can feel the power in the VHR. The HR feels like it has a lighter flywheel and is much more eager to rev. The throttle is definitely very touchy, so perhaps the VHR dampened the touchy throttle.

One thing I know for sure is that the throttle response in the DE/HR remains the same regardless of temperature even after a long drive. The VHR throttle response appears to worsen after a long day of driving.

It's the VVEL, you can feel the cams working

I feel like an LS6 swap is the cure for this throttle issue.

Wow. So wassup with the UPREV throttle tweak?