Nissan 370Z Forum

Nissan 370Z Forum (http://www.the370z.com/)
-   Member's 370Z Gallery (http://www.the370z.com/members-370z-gallery/)
-   -   dmhenderson's Nismo '12 GTM supercharged build thread where I freak out a lot (http://www.the370z.com/members-370z-gallery/71817-dmhendersons-nismo-12-gtm-supercharged-build-thread-where-i-freak-out-lot.html)

Baer383 08-22-2013 12:16 PM

Quote:

Originally Posted by carlitos_370z (Post 2456653)
sound like a fuel cut or like Baer383 said!!!

Throttle cut is always first followed by fuel cut followed by fuel restore in that order.

Sh0velMan 08-22-2013 12:18 PM

Quote:

Originally Posted by dmhenderson (Post 2456569)
Odd behavior (and this may just be me not knowing boosted cars):
Pulling hard in 2nd and got a little too close to redline and near peak I had a sudden and almost complete loss of power. Shifted into 3rd and was fine. What gives?


Sent from my iPhone using Tapatalk - now Free

If you have not disabled ETC in your ROM, this is throttle cut. Completely normal. It literally closes the throttles on you.

If you disable ETC it can only cut fuel, which is a slightly less safe way to limit RPM, especially if you're boosted. (Ideally you'd cut fuel and spark, but cutting spark results in backfiring and emissions-conscious automakers won't blow fuel out of the engine no matter what.)

I have ETC disabled so fuel cut is all I have, and for me, it's fine. It's a lot less abrupt than throttle control, but can cause the engine to stumble when you get back into the throttle, if you're really beating on it.

Sh0velMan 08-22-2013 12:19 PM

Quote:

Originally Posted by Baer383 (Post 2456657)
Throttle cut is always first followed by fuel cut followed by fuel restore in that order.

This is correct.

Fuel restore is generally a lower RPM than the fuel cut (rather than the same RPM). If your ETC is enabled, you shouldn't really hit fuel cut in normal circumstances, at least N/A. I suppose you could have so much boost in the pipes that revs could continue to climb after the throttles begin to close, under low loads (1-2 gear).

Baer383 08-22-2013 12:28 PM

Quote:

Originally Posted by Sh0velMan (Post 2456664)
This is correct.

Fuel restore is generally a lower RPM than the fuel cut (rather than the same RPM). If your ETC is enabled, you shouldn't really hit fuel cut in normal circumstances, at least N/A. I suppose you could have so much boost in the pipes that revs could continue to climb after the throttles begin to close, under low loads (1-2 gear).


It is on,he is running Sam's tune.

dmhenderson 08-22-2013 12:39 PM

Learned something new today. Thanks!


Sent from my iPhone using Tapatalk - now Free

dmhenderson 09-06-2013 09:48 AM

Update on tune: With the cats off it and the ART pipes on, before even starting to tune the car we are at 470whp. Lesson we've learned here: Superchargers do not like cats.

Whoever bet I was going to lose power with those pipes owes me a beer.

Baer383 09-06-2013 09:51 AM

I have 516 rwhp with stock cats on.

carlitos_370z 09-06-2013 09:57 AM

great to hear that my friend!!!:tup:

dmhenderson 09-06-2013 10:00 AM

Cats on: 450whp (no tune)
Cats off: 470whp (no tune)

I'm not trying to beat your dyno number, I am only interested in gains. This might be useful info for someone else on down the line.

Baer383 09-06-2013 10:02 AM

The cats keep back pressure and with the VVEL in these cars the back pressure will help with cylinder fill,I put Berk HFC on and lost 35 rwhp.

dmhenderson 09-06-2013 10:10 AM

Definitely strange. You'd think pipes would cause more of a loss but they didn't. Same dyno, same tuner so it's definitely a legit gain.

Chuck33079 09-06-2013 10:12 AM

So how much fun have you been having with it since you've gotten it back? It's amazing how well these motors take to boost. And the chassis handles the power like it was meant to have it.

theDreamer 09-06-2013 10:29 AM

Quote:

Originally Posted by Baer383 (Post 2475504)
The cats keep back pressure and with the VVEL in these cars the back pressure will help with cylinder fill,I put Berk HFC on and lost 35 rwhp.

I wonder if it is since he is just running the GTM canned tune, and it is fairly tamed overall, that just opening it gives some extra HP.

jpritche 09-06-2013 11:41 AM

Quote:

Originally Posted by theDreamer (Post 2475579)
I wonder if it is since he is just running the GTM canned tune, and it is fairly tamed overall, that just opening it gives some extra HP.

:iagree: My thought process exactly.

dmhenderson 09-06-2013 09:36 PM

I'll have final numbers once they get in there with the Uprev software tomorrow morning. Dropped off the GT-R spark plugs earlier this evening.


All times are GMT -5. The time now is 09:30 AM.

Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
Search Engine Optimization by vBSEO 3.6.0 PL2