I have been running my setup reving to 9000rpm for quite some time today, but today I installed an MSD soft touch rev limiter to cut ignition instead of fuel in the top end rev limit so I set the MSD to 9000, and went to set the ECU fuel cut to around 9200 but every time I set it at anything above 9000rpm it would default and reset back to 9000 whenever I click elsewhere. Upon playing with it more, I find out that the lowest hot rev limit is 2500, so it seems that the hot max rev limit is 9000 only??? Am I missing something or what, i thought I read on ZDYNE's site somewhere it can rev safely to 10,000-11,000? Any input would be great... I tried changing high rev limit on diff tunes as well and it did the same thing.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">Rev Limit can be reconfigured to any value from 1000-9000RPM. Not simply removed, that is unsafe read on...More on Rev Limits.</TD></TR></TABLE>

http://www.zdyne.com/alterhome.html

 

Aw **** well that's no good..

 

Yup.

There simply isn't enough space on the OBD0's for that many RPM/load columns.

Man, that site hasn't been updated in like 8 years. I wonder how he can still sell those things?

 

Haha I know. if he were to make a new release of ZDYNE, I think it would sell quite well if it has all the up to date features. Cause we all know, ZDYNE is OLD school. But for me it works just fine. But a little more features would be nice. I left him a voice mail.. he'll prolly call me back today and I'll ask him about it maybe.

 

Yeah, too bad he hasn't continued development of it. Even if he doesn't have the knowledge to do it he could hire the development out. Oh well.

 

i agree totally, if he did some updates, got his datalogging working(that he has been saying forever that he would do). it would be an even sweeter unit for us obd-0 guys.

 

I rock Zdyne. The launch control and WOT shifting is sweet, but yes, an updated version would rock even more.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SpeedingHatch &raquo;</TD></TR><TR><TD CLASS="quote">I rock Zdyne. The launch control and WOT shifting is sweet, but yes, an updated version would rock even more.</TD></TR></TABLE>

But too bad the ECU uses a fuel cut to control the launch and WOT shifting...

 

Yeah.. I use an MSD 2 step to do all that. If onyl ZDYNE took today's features adn upt it into a enw ZDYNE, he would sell so well.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Bryson &raquo;</TD></TR><TR><TD CLASS="quote">

But too bad the ECU uses a fuel cut to control the launch and WOT shifting... </TD></TR></TABLE>

doesnt hondata as well use fuel cut for their launch control?

i am curious about this, why would fuel cut be so bad, no fuel = no combustion, i did a bunch of searching and people have mixed opinions about this. i couldnt find any "expert" opinions.

 

Honda felt it was a safe enough method of rev limit control.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by speeddave &raquo;</TD></TR><TR><TD CLASS="quote">

doesnt hondata as well use fuel cut for their launch control?

i am curious about this, why would fuel cut be so bad, no fuel = no combustion, i did a bunch of searching and people have mixed opinions about this. i couldnt find any "expert" opinions. </TD></TR></TABLE>

it does work, but doesn't work that great. It's easier to get an exact RPM for a limit VS the fuel cut. From my experience the fuel cut has a fairly large rpm variance compared to ignition cut. I used the Hondata 2 step with my last setup and found that it would knock a couple seconds into it, and wouldn't hold the RPMS stable at all. I havn't had any issues with my MSD however.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by crxrocks &raquo;</TD></TR><TR><TD CLASS="quote">Honda felt it was a safe enough method of rev limit control.</TD></TR></TABLE>

But then again, Honda motors are all N/A from the factory. When you factor in load and boost, I think ignition cut is a much safer method.

 

I agree it is safer, but for launch control (when you aren't seeing boost anyway) it is ok. ;-)

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by crxrocks &raquo;</TD></TR><TR><TD CLASS="quote">I agree it is safer, but for launch control (when you aren't seeing boost anyway) it is ok. ;-)</TD></TR></TABLE>

But chris, thats the point of the launch control. The 2 step helps you build boost at WOT, so you have more power off the line, and all you have to worry about is clutch modulation.

 

You don't really build boost while reving in 'neutral' anyway, do you?

 

Depends size of turbo.. I can build about 10psi with an ignition cut 2 step at 4000rpm

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Bryson &raquo;</TD></TR><TR><TD CLASS="quote">
But then again, Honda motors are all N/A from the factory. When you factor in load and boost, I think ignition cut is a much safer method. </TD></TR></TABLE>


How much load is on a boosted motor when it runs out of gas? I would personally prefer ignition cut over fuel cut but if the motor is getting no fuel, its not being stressed.

 

On a fuel cut limiter, there is still always taht one chance in a million sparks that the engine can reintroduce fuel halfway through a ignition, which results in a really lean combustion.

 

Honda ecu's are pretty smart, it's not real likely that it's accidentally going to open the injector during an engine cycle when it's not supposed to...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by crxrocks &raquo;</TD></TR><TR><TD CLASS="quote">You don't really build boost while reving in 'neutral' anyway, do you?</TD></TR></TABLE>

It's different than reving in neutral though. like Tchleung said, you can built boost with the 2 step. can't do that in neutral. I would get about 8psi with the MSD set at 7K on my last setup.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tony1 &raquo;</TD></TR><TR><TD CLASS="quote">Honda ecu's are pretty smart, it's not real likely that it's accidentally going to open the injector during an engine cycle when it's not supposed to...</TD></TR></TABLE>

Indeed. I think it's just easier to aim for a certain RPM with an ignition cut VS a fuel cut.