cturnbull802

i think the rev limiters are set to there respective 6600 and 7100, the tachometer is the one at fault here

skaterbasist

iTrader: (3)

From what I understand, the rev-limiters is preset by the ECU which cuts the fuel in order to prevent over reving. That has never happened to my revup, and have taken it to 7400 RPM's stock.

Im guessing the ECU cuts the fuel (rev limit) on the revups at 7500 RPM?

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DMK

iTrader: (6)

Just gas it in neutral and see where it bounces off of. Not life-threatening to the engine if you hit it once in a while.

To others:
For the non-revups, would it be wise to raise the revlimit to past 7100? Say, 7500?

97supratt

iTrader: (61)

It's not just about raising your rev limit. Even if you rev to 7500, you're not making any power in that rpm range. Unless you have various parts which make power in the upper rpm's you won't get a gain out of it.

I have the HR and I shift around 7200 rpm even though redline is at 7500. Thats where peak power is made.

skaterbasist

iTrader: (3)

I actually reved to 7500 just to see it I could make it past the line in 3rd. At LACR, I can get past the line at 7200 RPM's on the revup which is fine. I tried the same thing at Cal Speedway, and ended up reving to 7500, although not on purpose.

I actually don't agree with the Peak Power theory that many go off, especially if you own a VQ35HR. Im sure you have noticed many dyno's, and the hp drop after peak power is very small.

In my case, I made peak power at about 6300 RPM's, but only lost 5 HP from peak power to 7000 RPMs. Acceleration will not stop unless theres a dramatic drop of power.

I've tried this at the track, and shifting at 'peak power' only yielded a slower time.

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97supratt

iTrader: (61)

Screw dynos, i'm comparing my own track times. What you're talking about ending in 3rd gear at LACR rather than 4th is a different story. Thats just you slowing your time down by shifting another gear.

I took my HR to LACR and when I shifted at 7500 from 2nd to 3rd, and 3rd to 4th, I got a slower time. I tried this on 4 runs. May I remind you, I got 20 runs that night.

In first gear I always shift at 7500 only because it puts me exactly where I want to be in 2nd gear plus the engine is revving so quickly that you won't feel a power loss. In the upper gears you actually feel the hp drop. If you look at the dyno, thats about where the peak power is 7k rpm. I shift at 7200 just to give a few hundred rpm of room for the next gear.

Just my opinion, but if you want I can show you the difference at LACR sometime.

Best time so far in 75 degree weather with sand and a horrible head wind 14.2@99mph. Bone stock.

skaterbasist

iTrader: (3)

Screw Dynos? Your going by peak power. That's all dyno statistics there.

Never mind the shifting into another gear story. That was just an example for something completely different.

If you believe your 'theory', that's what matters (I guess). As for me, I have always gotten better times by shifting at redline rather than at "peak" power. And no, it wasnt because an avoidance of an extra shift. I have tried multiple ways (on the same track), and redline always yields better times for me.

By the way, that's an excellent time for an HR over at LACR. Best I've seen a stock Z accomplish (VQ35DE) wasa 14.5.

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97supratt

iTrader: (61)

Another thing to remember is, what you see as far as RPM isn't exact. You might see 7200, but rev limit on the REVUPS are at 7000.

Yeah LACR is just horrible, the best 60ft I could muster was 2.2 because the prep is so bad there. I'm hoping I can go back with some more mods in a few weeks and Drag Radials and hopefully get a mid 13 second run and trap higher than 100mph.

Chebosto

iTrader: (43)

the only reason to adjust higher RPMs for for people with cams that are making more power all the way to redline, and for those that want an extra buffer during shifting as not to hit the rev limiter.


what you think you see on the analog tach is not the rpm # that the computer sees, so some might have seen the needly fly past what the factory limiter is set at...

for the 287 engine (non-rev up) i would not suggest setting the rev limit to anything past 7200/7300. (factory is 6600) there were some tests done in japan that shows that the VQ's rods failed from sustained rpms > 7600.

for the rev-up engine, add 500-600 more rpms to your factory limiter (for a new rev limit in the near the 7500-7600 range) and that is what is typically set on the reflashes.

F spec costs more than Lspec due to the amount of map editing that is needed and the added capabilties. Don't bother arguing why -- it just is. do a search and read up on the threads that we went over 4 years ago when the ECU first was released and why it's priced that way.

Feedback refers to the what a stock ECU will attempt to do to correct itself to the factory programmed maps when it senses a lean condition (due to plenum mod or hfc) by retarding timing X amount and/or adding Y amount of fuel to the mixture.

Steve-O Z33

iTrader: (10)

I hit 7500 today in 2nd and when I hit 3rd, everything in my head unit cubby hole flew out. The responsiveness and the smoothness of power delivery is GREAT.

DMK

iTrader: (6)

Sorry, I was basically asking if the non-revup has the valve springs to handle that high of a redline and would also be safe to do so. It was in regards to a car with FI, more specifically a SC application.

97supratt

iTrader: (61)

I'm sure it can handle 7000rpm.

cvt

iTrader: (1)

i want to get a reflash so bad...but technosquares business hours are only on weekdays..

DMK

iTrader: (6)

Ya, I was specifically referring to a 7400-7500 redline for the non-revups on a FI application.