|
Originally Posted by MazdaManiac
Just another fix - I'll post it elsewhere as well:
Switch the first rotary switch inside the E-Manage from "B" to "8" and all four ignition circuits become active. This means, you can wire the ignition harness and control timing on the leading AND trailing plugs. I don't know why I didn't try this sooner. This doesn't seem to affect any other aspects of the E-Manage operation and the RPM is still correct. I'm not up on the extreme deatils of the timing of the sparks and the rotor's position during those events, but here's a question: If we start to retard the firing of the trailing plug, how much headroom do we have before we start to preignite the next chamber as it rotates over the trailing plug? I'd just like to have some idea before I start to fiddle with retarding trailing plugs. |
It would be so retarded that it would be outside the range of the E-Manage's adjustability.
Since you are only concerned with spark under power, remember that the Renesis is already running 20° to 36° of advance under load (40° at throttle lift!). This means you couldn't even get the trailing to fire a TDC with the ±20° range of the E-Manage. You will never want more than 16° of retard, anyway. The main advantage of my little discovery is that the timing split is retained and we don't have to wory about the trailing causing knock (which was unlikely to begin with). |
Originally Posted by MazdaManiac
It would be so retarded ....
:lol: :lol: :lol: Sorry. Couldn't resist when I read your phrasing... haha |
:ylsuper:
|
How much spilt is there at load? Is it possible that by retarding only the leading plugs that the trailing could fire in advance of the leading?
|
I guess it is possible. RotaryGod would have a better idea of how that works.
I imagine that at some times, there might not be any split, which means retarding the leading might yield a negative split. That would be bad, mmm-K. |
^I've been wondering about that. By wee-tahding the leading plugs so that they fire after the trailing plugs, the effect would still be wee-tah-did ignition, but not by as much as you would be specifying with the emanage, since the amount of wee-tahd would be capped by when the PCM fired the trailing plugs.
Since its so easy to do, and apparently I can't wee-tahd the trailing plugs so much that they ignite the next chamber, I'll just rig it up when I get back to NM on Sunday. BTW: I got my custom 3" exhaust made and installed while I was away. I'll be tuning this week and dynoing next weekend! WOO! |
I'm Sofa King Pea Said Off. I'm going away for work and won't be here in Phoenix for 10 days.
I was hoping to spend some time tuning as well. Time to ditch your CAT, too. |
MadDog, first i would like to say thanks for doing all this work as some People do not understand the risk you were taking doing all this testing.
I am an owner of a very highly modded 3rd gen RX-7 and found that running high boost I needed some aftermarket ignition parts like amps and coils. I am wondering what plugs you are using right now with your map? Again thanks for saving us a ton of money and time making this a very cost effective and safe kit. In the RX-7 community it is like pulling teeth to get help with maps. I will be installing a Greddy kit and am very interested with timing control. Thanks again Steve |
Also, have you guys upgraded your cooling system yet and if so were there any fitment issues with your after market rads(Fluidyne,Koyo)?
Thanks |
No problem. I do what I can.
I'm using the Denso Iridium plugs one step colder. I haven't yet added an aftermarket radiator. But, I did add a Fluidyne oil cooler and switch to Royal Purple. I did a DYI thread about it. That cooler adds about 1.25 qts as I recall. |
good luck getting a Mazda Tech to reprogram a used computer from a different car ... |
Originally Posted by TeamRX8
good luck getting a Mazda Tech to reprogram a used computer from a different car ...
a im waiting for someone to play that one out. beers :beer: |
Originally Posted by swoope
yea,
a im waiting for someone to play that one out. beers :beer: I haven't been able to come up with the second unit yet, but I'm confident the the dealer will work on it when I do. |
Originally Posted by MadDog
So, on to why I'm all of a sudden wanting to control timing. Well, we were all wondering why the GReddy turbo can't hold boost in the higher RPM. I'm now convinced that the majority of the problem is the wastegate actuator. I cranked down on the adjustment as far as I could, so as to preload the spring as much as possible. With the additional load on the wastegate flapper holding it closed, I can just about hold 7.5-8psi all the way to redline. This is about 3psi more than I could before! The actuator is just too weak to hold the flapper closed as the exhaust gas pressure increases in the higher RPM.
Now, I realize that the opening of the runners results in a step increase in exhaust gas pressure. This increase in force on the flapper exceeds the preload on the actuator and opens it - resulting in the boost dropping after 6kRPM. I don't know why we didn't think of this before. So, while I didn't need to control timing before, once I adjusted the actuator I started to get a little detonation in fourth gear above 6kRPM. The AFR was fine - 11.5 and the injector (490cc) duty cycle was only at 78%. Fuel wasn't the issue. It was just time to get my ass in gear and start adjusting timing using the eManage. I used the timing MAP that Jeff posted a while back. Bingo - no more pinging. So there you have it folks. I have some concrete evidence that the wastegate actuator is to blame for the boost falling off. An external wastegate is the best option, but, you should be able to hold a few more pounds just by adjusting the actuator to max out the spring preload. Wow. Adjusting timing and completely controlling my injectors with the $289 eManage blue. I'm still less than $5k into it and I'm faster than an STi! I'll head back to the dyno soon for some concrete numbers. The WRX guys have also tried to tighten down the wastegate like you have, one problem that arose was the wastegate would not fully open after this adjustment. Causing boost creep at higher rpms. So instead, they are installing helper springs to keep the wastegate closed but still allow the full movement of the wastegate. Its cheap and seems to work. Here is a link to a write up. *Warning* This MAY change the wastegate open psi by alittle bit. http://forums.nasioc.com/forums/showthread.php?t=589293 |
I cannot find any 1n4007 Diodes at any local stores..
will a 1n4005 work? |
Yes. Tecnically, LEDs will work. However, they don't like staying at 200°F for too long....
|
Originally Posted by VarneyMazda
I cannot find any 1n4007 Diodes at any local stores..
will a 1n4005 work? http://www.futurlec.com/Diodes/1N4007.shtml There is a pdf that compares them. I'd send you the 15 or so extra ones I got in the package but the postage is worth more than the parts. |
Radioshack has them in the back of the store, you can use pretty much any of the series 1N4001, 1N4002, 1N4003, 1N4004, 1N4005, 1N4006 or 1N4007. They range from 50v to 1000v, all at 1.0 amp. You'll never come close to the voltages that they're rated for in the car unless your RX-8 gets struck by lightning. I'm using the 1N4005 because that's what Radioshack had in stock, 600v at 1.0amp. It came in a pack of two for $2.59, I tossed the other one.
Just refer to TurboX8's link above for the specs. In the very unlikely event that any of these fail, they pop like fuses with no harm, just go up one in this diode series to replace. Many electronic device use diodes as a secondary fuse on the circuit board. |
this is redundant, but i must say after i got the fix #2, all i can say is WHAT A DIFFERENCE!!
i don't know why i didn't do it sooner. powerband is alot more predictable, and just the overall driveability improved tremendously. time to start increasing the boost :mdrmed: by the way, my mechanic opened up the plastic flap in the right front wheel well cinderliner & drilled the hole in the exposed pipe there. is this an acceptable location? |
FYI everyone install your fixes, for some reason my air compressor brunt up prior to installing the fix.
Not that its a huge problem but i do get CEL's once every 500 miles |
Has anyone posted pics of these, so called, severed injection wires?
https://www.rx8club.com/attachment.p...chmentid=76821 |
Originally Posted by carbonRX8
Has anyone posted pics of these, so called, severed injection wires?
Originally Posted by stickmantijuana
well... couple weeks later, my rx8's back to its old self again. i think pcm retuned itself. :wallbash:
Mine just keeps getting smoother and smoother. |
A couple of questions before I go ahead and do this....>
For fix number 2 > Any pics on this? Exactly what hose do I remove from where? and what do I do with the "opening" that is left where the hose was located? :) *confused* For fix number 3 > When cutting off the primary 2 injectors, what purpose do they do? The tertiary intake port will still open at its specific rpm, but will the p2 injectors still deliver fuel there? The reason I´m asking is that I´m planning on upgrading to a bigger turbo in the future, wich will most likely requre more fuel. Wouldn´t the p2 injectors come in handy then? If cutting them off we are left with 4 functional fuel injectors and not 6. Please correct me if I´m wrong here. |
You still use the P2's...the e-manage just controls them 100% instead of piggybacking them and letting the stock ECU use them as well. This gives better control of the fueling and less fuel trim problems
|
| All times are GMT -5. The time now is 10:58 PM. |
© 2024 MH Sub I, LLC dba Internet Brands