MadDog

Since things are running so good at 8.5-9 psi right now, I'm about to start up-ing the boost. I've extrapolated the current MAP to 10psi. I used the same method as I did last time to extrapolate to higher boost levels: fit a linear function to the highest 4 pressures in a given RPM column and evaluate the fitted line at the new pressures. It worked great going from 7.5psi to 9 psi. The resulting values on needed fine tuning by a couple of percentage points. Tuning seems to be pretty linear on the Renesis.

You can see that the bottom left cell in the 10psi MAP pushes the 490cc injectors to 100% duty cycle. I started looking for where the 490cc injectors really start to peter out. Paying attention only to the cells that actually get used in WOT driving, I could boost to about 12psi before running out of capacity - I think. For now, I'm thrilled to be on the brink of double-digit boost! 10psi is as high as I want to go for now. If only I had a T4 at these boost levels....

One more thing - if it weren't for the ridges in the MAP around those lean spikes, there would be much more available capacity from the 490cc injectors. Someone needs to figure out how to get rid of those by controlling the port timing. I haven't tested the always-open state. That might be the ticket.

MazdaManiac

iTrader: (3)

I'm going to look into having RC re-port the OEM 390cc injectors out to 550cc.
I am also going to look at RX-7 injectors and see if they are the same as ours, in which case it will be cheaper to simply buy 550cc injectors on e-bay.
That should get us out to 12 PSI quite safely.

epitrochoid

cool to hear you and MM have the emanage working properly. greddy owes you two a favor!

fwiw -- the interceptor can control the port timing, although I don't know if there's much power to be gained by that alone. if it did allow you to push the injectors higher across the the useable power band, then you could pump more boost, but with this dinky turbo I'm not sure how much power that's gonna actually give you.

MazdaManiac

iTrader: (3)

Power isn't the goal with regards to port actuation - control and transitional smoothness is. Increased power would be a byproduct.

The turbo isn't dinky - remember, I did the compressor flow map comparison and it will produce way more boost than we need and still stay in the most efficient part of the map.
Now, the turbine could probably use a porting (to actually slow spool a bit and reduce exhaust manifold pressure which is probably 2 or 3 times higher than manifold pressure right now) and the WG flapper should probably be enlarged, but the turbo is powerful enough.
People that are having boost drop-off issues are experiencing something else and I'll get to the bottom of it, but it isn't because of the size of the scroll.

I was using (and will be using again at some point) a T4 compressor and it is operating at the absolute bottom of its efficiency range in our application. The main advantage is low RPM surge avoidance, but we have tackled that with the WG signal mod on the TD06-18g that Greddy uses.
If you intended to build a Renesis fuel delivery system that could support 21 PSI or more, than I'd say the Mitsu turbo is too small. But since we are pretty much limited to sub 14 PSI peak, I think it is just right.

The boost fall-off, BTW, may be premature WG opening (because of extreme exhaust pressure), but if people are experiencing it with external WGs, then probably not...

WantedTwo

iTrader: (4)

ok Here go some questions; In regards to fix #2 the pressure sensor for the e-manage needs to stay on the manifold right? if this is the case than my EO-1 that leaches this signal to control the wg will be like nothing happened if I move the wg tube. so do I need a second presure sensor for the EO-1? Second, 7 psi is all we can get from just useing the 2nd injectors? it seems that is its max since tim said he had to push some of it off on the prims. So the question is were does this map end? Thanks for the help on this, and MM and tim, you two are the ****. I'm gone on tdy for a month and you two bust loose. I think I should be gone more

BTW is this map cool for people running catless?

MazdaManiac

iTrader: (3)

No. You still want the E-01 to see manifold pressure. It will decide what to do with the WG signal. This is the beauty of a computerized boost controller. When it sees vacuum in the intake, it will allow the WG signal to continue unabated to the WG can. This means less un-used boost in cruise situations. When the manifold pressure climbs into boost, it will start to modulate the WG signal to hit the target boost based on the set, start and duty cycle settings.


You can see that Tim's maps start to put the injectors in to a static situation at high RPMs. By 9200 RPM, there really isn't enough fuel left to support more than 5.5 PSI or so on the OEM injector setup.
However, you can set peak boost much higher at lower RPMs and taper to that point. Some people are experiencing this in an uncontrolled manner in that they are having boost fall-off problems.
The idea would be to run out to 8 PSI until 5500 RPM and then taper off to 5.5 PSI by redline.
With the bigger injectors, you can easily boost out to around 10 PSI and start scaling back to 8 PSI by redline.

Yeah, I'm CAT-less and it works great. I'm about to install an MS exhaust which will flow even more and the net effect will be more air at the same pressure level. I'll watch the A/Fs, but I will also have the larger injectors in place by then, so YMMV.

rkostolni

There's a dyno graph posted in the Australian forum from a guy with a custom turbo, I think it was a T3/T4, and his boost dropped off to 7psi at redline as well. So I'm not convinced its a problem with the turbo being too small either, even though every other person I talk to says that's the reason. That would be awesome if we could fix that problem. We could definitely break the 300hp mark.

Does your boost fall off Jeff?

MazdaManiac

iTrader: (3)

Actually, on the Greddy it stays the same and with my T3/T4 pressure would climb past my boost target. I blame this on a WG flapper that is too restrictive.

WantedTwo

iTrader: (4)

ok sweet than I'm going to lowes to get parts, so have the boost taper down sounds great but how do I do that I look at my profec and say hope its working. all I understand with that thing is when I did my CZ tuning and the gain effects total boost pressure across the board. Also, I'm sure I need to take off the cupler after that right angle peice to sweap out shaving from the tap right? or am I not to worry about it. Thanks!

Also what in the hell do these things look like so I can find em?

damn forgot to say what things: 1/4NPT - 1/4 hose barb fitting. <----- Those

rkostolni

Wow, that's odd. Everyone else has this problem. How much boost are you running?

MadDog

Well, I just got back from running the new MAP and boost controller settings. First, let me say that I have not yet learned the boost offset settings. They appear to have a much greater effect in the higher gears. I haven't dialed them in yet, so I actually was running nearly 11psi before 6RPM!! So, I didn't run it too far up the RPM range.

That being said, I have no reason to believe that there are going to be any problems at all once I stablize the offset. Here is a shot of the e01. You can plainly see the zone that I tuned rich to handle the also obvious lean spike. The lean spike occurs in the higher RPM for higher gears. This was a 5th gear run, so the spike occurs later in the rich zone. The peak was 12.0 AFR. Like I said, I have to dial-in the offset numbers, but I have every confidence that this will be just straightforward as 9psi was.

KJ238

I just did fix #3.... I am rich in a lotta ranges including when i am not in boost and in some ranges when i am in boost.

Question: Is the air flow hooked up? I can tinker with the airflow adjustment map to correct the points when i am not in boost, correct? putting a -x% value decreases the signal by a certain voltage = yes/no ?

But other than that fix #3 was great at full throttle.... 12.5 almost all the way! Beautiful...

MM: Still can't get ignition timing to work.... I have re-checked everything... Doesnt seem to want to work. Jumpers 1 and 2 are set to 1-2. And my setting is BA2 ( i think). I even went as far to replace the 1N4003 capacitors i used before with 1N4007's that u use. Do i need to set anything with the e-manage support tool to get it to work other than turning on the ignition map?

Thanks for the help before hand...

RX8PDX

I am glad that I have waited to get a turbo kit.

The Greddy seemed like the kit to get, for the HP level I wanted, but with all the problems I wasnt daring to do there.

Thanks for all the work.

Guess I have to start working some overtime to get a kit!

Also, to the 1N4003 and 1N4007 are diode, not capacitors. A typo I am sure, but they function very different.

MadDog

What RPM ranges are you rich while not in boost? How rich is rich? If its below 6kRPM while not under boost, then its the PCM and not the eManage. The MAP for the severed injectors adds fuel to the non-boosted range only above 6KRPM. If you are rich below 6kRPM, I'd wait a couple of days to see if the PCM will adjust this range.

Glad to hear the boosted operation is smooth. 12.5 feels great, but is a little lean. I'd add a couple of points to richen it up for safety. Now that you have a good starting point, its time to tune it yourself. That's the main advantage of taking control of the P2's yourself. Tuning is much easier, predictable, and the PCM can't do much at all to undo what you do.

-MD

KJ238

I highly doubt that the pcm will tune it out..... Coz the problem has existed for a while ard 4k for ranges ard -0.2 to about +0.2.....

Fix #2 made this not so evident...

But when i severed the injectors it is now rich from ard 3k at the range at about -0.4 to about +0.3.....

When i say rich, i mean my AEM o2 guage falls all the way to the left and shows no number (< 11) and car runs flooded and exhaust goes boop boop boop until i let off or step on the throttle.... I only get this on constant throttle mostly...

I am still not sure whether the airflow adjustment map works.. If it does i could correct this.... Am waiting for confirmation before i go out and start tuning... This is REALLY annoying as i can't really drive the car properly unless i am full throttle. In the past i drove ard the ranges... but now the range is so wide, it is hard to drive ard...

The ranges in boost i can handle by tuning the fuel mapping..

Thanks again

rkostolni

I'm going to guess you severed the secondaries instead of the P2 injectors.

MadDog

You mean you are running rich in the transition from vacuum to boost? Thats highly unusuall. Which map did you load? If you are running rich in the transition range, then take out some of the fuel that I added at 0psi. Can you post a log of AFR, boost and RPM?

MazdaManiac

iTrader: (3)

First, make sure you severed the correct injectors. Blue and green in this post:
https://www.rx8club.com/showpost.php...5&postcount=14

Second, exactly how are you wiring the ignition. Describe it exactly. If you have pictures, it would help.

MadDog

Severing the wrong injectors would seem to me to cause a lean condition below 6kRPM. Above 6kRPM I'm not sure what would happen. Both the PCM and eManage would be trying to fire the P2's for about the same duty cycle for non-boosted operation. I don't know if this would make-up for the lost fuel from the other injector that would be getting no signal if he severed the wrong ones.

MazdaManiac

iTrader: (3)

I just want to go item by item with him on it. We've been discussing the ignition thing for a while and he hasn't been able to get it to function right.
I might have to fly to Brunei to take a look!

MadDog

Well, if you go, be careful not to become one of those "ships of the desert" if you know what I mean...

BTW: 10psi feels awesome!

MazdaManiac

iTrader: (3)

Yeah 11 PSI will be the holy grail. I think for most driving, a consistent 9 PSI is really the the mark by which to measure.
On most of the aftermarket turbo cars I've worked with, anything past 11 PSI is where things start to break peripherally and drivability becomes an issue.
It is really hard to get past 11 PSI with smooth results and nearly doubling the power output of a motor does magical things to the drivetrain which follows it.

adrian-1

Sorry to ask the obvious, but what flash are you on?
Maddog and MM are still on the M-flash. The R-flash is richer.

If you had the Interceptor, there is no need to worry about what flash your on (Shameless plug for mazsport.net)

KJ238

For the injectors.... I have severed as per your intructions to the first post...

I followed the colours exactly as u described in the first post.... Both wires i severed were on the small connecter and were shrink wrapped.... The problem i have was already happening before i severed the wires, it is just more evident now after i severed the wire.

Like i said it's rich, not lean... I can see what voltage the ecu sees for o2 from the apex'i turbo timer... It read ard 1.04v when it start flooding... Only seems to start once i reach 4k rpm and am at constant throttle... Prolly ard 15%-25% throttle. I'm considering using the airflow adjustment to tune this thing out... It has made me really really annoyed.

As for ignition, I'll describe it in detail tomorrow MM.... It's 2am here and i'm really tired... Do you have msn? perhaps you can pm or e-mail me ur addy....

Maybe not serious enough for u to fly to brunei lol...

WantedTwo

iTrader: (4)

Hey MM when you get you new p2's it would be stellar to do a diy