Ian:Stainless sheetmetal brackets and 7075 spacers I fab'ed.
http://the-rotary.net/images/rx-7/CY...BMEP_coils.jpg


The thermal/reflective tape was lifting but has been fixed since. Also decided to reverse the orientation to better isolate the plug wires.
http://the-rotary.net/images/rx-7/CY...Overhead_1.JPG

I can not find any faults in your set-up. All I can say is WOW. Please continue to educate the rest of up.

Go the Mercury Coil !
 

Hey Carlos,

I've been a member of this forum for ages and have been reading it for much longer, but this is my first post. Your sagas with ignition ( and your seriously cool car ) have inspired me to add to the discussion.
I run an EMS Dual Sport ECU, M & W Pro 14 CDI, Mercury coil setup on my GT40R BP FC and love it ! Mine are mounted in a similar position to where you had yours and have been there working perfectly for about four years. I would be the first to admit though that the Mercury coils can be little devils ! When I first installed them I also had the broken ferrite thing and some grounding problems. The one thing I can suggest though is that it is most important to use a quality silicone between the ferrite tube and the coil body. This little trick makes all the difference !
I hope you go back to the MM coils eventually coz when they work the way they are intended they are awsome.
Good luck.

Cheers,

Tony

Do you have the R500 installed in the engine bay or cabin ? Be careful , I installed one in my engine bay and it died a premature death . I suspect it was heat related .

What is that on the transmission tunnel? A grounding strip?

https://www.rx7club.com/attachment.p...4&d=1231914822

It looks like all the wiring labels say GND, so I would think that's a safe assumption.. The new Boddington's bracket is pretty nifty if I say so myself.. Car is getting new ID2000's (click for more info) and some tuning pretty soon here. I for one, am excited.

Doh... they all do say ground don't they! :)

Wow, six months without a post and we come back from the thread abyss... thanks.

VWH: yep, Grounding Bus to prevent ground loop issues... how'd ya guess? :lol:

Aaron: You're not the only one that's excite ! For anyone else that cares, I've been struggling to find the the time for the mechanical "due diligence" I've been able to afford in the past. Well, I've been coming up short. I finally swallowed my pride and sent to the car off to a pro to finish the tuning and complete a couple of small projects relegated to the back burner. So Yaw Power is going to stand in as my very capable mechanical surrogates. It's amazing to see progress without any effort on my part... I think this could be addicting! :rock:

The attached picture captures the first volley in my latest upgrade war. Thanks again for the Boodington's coolant overflow bracket Aaron! It finish off my rotary "black and tan" brilliantly!

wow those ID2000's look very promising.

Is it a special order to get them methanol compatible? Or are they all the same for $259/piece?

They are all the same. Where did you see them advertised for $259?

I assume the $259 came from the T1 Race Developement website...
http://www.t1raceparts.com/product_p/id%202000.htm.

Ahh, I think I saw the sale price of $239!

What EGT system do you have or xhat make are those EGT sensors for that matter?

Speedworks: I assume you're asking about the Exhaust Manifold Pressure (EMAP) ports. Those are just the two backpressure inputs that combine into an EMAP signal for the M4. The primary fuel & ignition tables for the MoTeC are mapped to ratio of MAP/EMAP by RPM, vice the more traditional MAP/Throttle by RPM.

I had a HKS EGT that I ran in the rear port. I chose to give up the input since I wasn't using as part of the ECU fuel/ignition compensation. I may add some in the future to just log in the the DASH. But that's for abother year...

sick build keep up the good work.

So rumor has that May might bring a shakedown just in time to make the Mazda Driver's event at VIR in June... guess we'll see if Murphy is still pissed at me!

Hey Aaron, any pictures of the newest sensor install would be very appreciated! :worship:

Murphy's agent and my conversion to a Bosch fanboy
 

Murphy's newest agent, E85, strikes at the 11th hour. Let this be a lesson to all of you converting, corn WILL scrub every last bit of rust from your tank and deposit in onto the absolute worst place.

Guess I'm now a triple Bosch setup: one in-tank feeding the surge tank and two pressurizing the fuel rails. Might come in handy with the 4 2000IDs in the rails.

Did you ever get the injectors working and the car tuned? Or did you find this rust during that?

Found it after preliminary tuning with new injectors... Dyno next week!!

Stump the Chump!
 

Well, we've been getting our arses kick all up and down the street by the new EFI install. Car runs like a champ: Start like OEM, idle smoothly, transitions seamlessly, runs great, hauls ass, and falls on its face at about 7K rpm. We've only tuned to 9psi so far until we figure out what's degrading the engine at the top. You can clearly hear the top-end hesitation in this dyno video: WTF!

At first we thought that it was a trigger or ignition issue. So out came the entire CDI setup and in went the Bosch inductive setup... same shiet!

We've exhaustively reveiwed the datalog... I know that I have at least 3 hours scouring just a couple of minutes of total dyno and street pull logs. I've ran correlations between every single channel in the car, and still the score is CYM Beayatch 1, Rotary Geeks 0!

Below is a representative log segment. Boost is controlled to 9 psi, fuel is E85 (actually 85% ethanol), and the CAS signals show no anomoly or interference. The vertical cursor is right at the hestitation onset... you can see it in the RPM slope's flattening.

http://www.the-rotary.net/images/rx-...YM_MoTec_1.jpg



The latest idea is to check for a possible restriction in the intake that might be acting like a restrictor... I just hope I didn't make a NASCAR mistake and leave something in the intake path (ala restrictor plate). Though I woudl be embarassed, it would be worth it just too finally solve the problem and finish this project.

OK, so what are some of you ideas? I've obviously failed miserably at solving the puzzle, so I'm hoping that a little "Rotary cowd-sourcing" might help. Bring it!

There can never b a restriction that kicks in only above 7000 rpm ! Check your trigger signals , and maps !.....................I rev to 11000k all day ! ..................u shoulda got a VIPECV 88 !

Sorry to hear about this, I've always been impressed with the things you've done with this car.

Does the dyno suggest the car is making abnormally low power? If there were enough of a restriction to keep the engine from continuing to rev, I'd assume the car would be down on power even before the 'false redline.'

On that note, what is the rev limiter set to? Are there any secondary rev limiters (launch control, etc)? Have you tried adjusting the rev limiter to a lower RPM (say 5000) to ensure it sounds or feels differently?

Have you tried using a timing light to verify the spark isn't doing anything odd? I'd think you would hear more popping and banging from a spark problem, but it should be a pretty quick thing to test.

Can you rev past that RPM at part throttle / light load?

The other thing we noticed is that the EMAP exceeds intake pressure almost exactly where the motor stops accelerating. We have a log from another car with almost identical turbo setups and EMAP increases gradually towards intake pressure nearing redline, but doesn't cross it...

Forgive me if I'm out to lunch, but weren't you guys going to try some Yaw-based experimenting where your maps (fuel and presumably ignition), used the ratio of MAP to EMAP as the independent axis? If so, I could imagine there being an issue here if the EMAP overtakes the MAP, as it would tell the ECU to select the fuel and ignition settings from that portion of the map. In this way, you'd have a negative feedback mechanism preventing further power production once that condition is met.

If you've got another car with the same setup running, maybe there's a faulty wastegate? A somehow obstructed runner that generates backpressure more rapidly? How do the EGTs compare between the two cars?

MAP/EMAP isn't really an experiment and is a standard efficiency calculation option in Motec ECU's. I've been running my car this way for the past couple years, as well as numerous other cars, including T1's 8 second integra. If EMAP overtakes MAP, the motor is at a lower efficiency and so should use less fuel... We're trying to figure out what's causing the restriction and decrease in efficiency, as the compressor map shows the turbo is well in its happy range at that point.

The wastegate seems to be functioning, as boost holds stable at 9psi. I've also thought maybe a physical obstruction in the manifold, but haven't had it all apart yet. I believe Carlos does not have any EGT sensors on the car, so can't compare that as of right now..

Thanks for all of the inputs gents. Definitely plenty of sound thoughts, some which we've also had.

Marcel Though I think you're right about an obstruction not being a point failure, were just checking for whatever sounds even remotely possible. It's sort of like when you've lost your keys or wallet and you start to look in places you know it can't possibly be (i.e the fridge or closets) but you're just perserving on hope at that point!

SCOTTY: Thanks for the kind words and very resonable questions. As for this challenge, it's all good. Been here several times (though to a lesser degree) in this rotary-masochistic fetish that I've developed over the last decade and a half. This too shall pass!

As is evident from Aaron's replies to your questions/comments, obviously great minds think alike. Unfortuantely I think we've already rejected most the possibilities posted. I have asked about rev limiters and confirmation that the MoTeC Traction Control was completely off, though I had low confidence that either was truly the problem source. If they were, it should have been a more dramatic cutout.

Calculon You had me thinking about the Map/EMAP efficiency mapping, till Aaron's reply. Unfortunately, I gave up the EGT ports to plumb the EMAP ports, so no EGT sensing in the setup. I think your right though, in that it might give critical indications especially between rotors.

Aaron THANK YOU for the contributions to this thread ! Your comments and replies are exceedingly welcomed. Best of all, you've saved me quite a bit of typing! ;-)

I've mentioned that the power drop correlated with low Lambda values and wondered if a malfunctioning LSU sensor might be faulting to a lean-bias. This may be no real correlation, but if there is, it might be sufficiently rich to rich-misfire even though it's not obvious in the dyno video or the log. In desperation, I wonder if E85 might have milder rich-misfire characterization than straight gasoline and therefore be asymptomic relative to the rich-mifire of gasoline. I'm sure the E85 tuners on here know how E85 rich-misfires... Enzo, Chris, Brian, Glen... a little help please!!

Have ya'll changed out the O2 snesor to reject the possibility.




I know there are one or two smart tuners on this list that have ideas. I sure would appreciate you thoughts. I've paid for my first track event in FIVE years and sure would love to drive the VIR Full Course at the end of August, but I could really use some help to pull it off at this point.

Carlos, I have a brand new bosch lsu 4.9 at the shop we could swap in as that sounds like a reasonable enough possibility.

I'm more than happy to contribute and try and get this thing going. It's just ridiculous that something like this happens to the most detailed person ever...

Carlos, nice to see you've got the right attitude about this. I had a professor who once said "How do you eat an elephant? One byte at a time." It was partly a cheezy programming joke but partly a reminder that even complicated things are just a lot of simple things stacked up or arranged in a very particular manner. I'm sure you guys will find it eventually. Didn't mean to imply that something simple like a rev limiter or traction control should catch you guys off-guard, but it's a nice simple thing to check and rule out quickly.


For what it's worth, I haven't personally done much work with E85 (just a couple of piston-engine cars), but what I've heard from more experienced tuners is that E85 seems less likely to misfire due to an overly-rich mixture. Both E85 cars I worked with made better power with a richer Lambda using E85 compared to pump gasoline (we tested on both fuels at one time or another). A friend's non-turbo Miata was happiest at an indicated 0.80-0.82L, and a turbocharged Nissan SR20 made better power simply by richening the mixture from 0.8-ish Lambda (E85) to 0.7-sh Lambda (E85).

Each car was using a different O2 sensor and tuned on a different dyno... neither was using a Motec O2 sensor or tuned on a Mustang dyno so don't get too hung up on the values. I've heard that most O2 sensors are generally designed and built for streetcars so they tend to be accurate near stoich and less accurate as the mixture gets further from stoich... then from there you've got to worry about the aftermarket circuitry that's talking to the sensor and interpreting the data. Long story short I'm not sure I'd trust the O2 sensor as the end-all be-all way to determine that the fueling is what the engine wants... presumably the tuner has already tried adding or removing 10% fuel to see if the misfire gets better or worse?

If exhaust pressure seems high (I've never measured and don't know what would be 'too high'), have you tried disconnecting exhaust pipes downstream of the turbo? Don't forget your earplugs!

Aaron: Thanks for the help, in what ever maner you chose!!

As for the O2 sensor, the hard part is actually going to be changing the sensor connector since I think there was an old LSU 4.0 in there. For that matter, Paul had asked me whether it's easier to change it from the top or the bottom, so he may have already done it.

Scotty Every input is welcomed. It's so easy for problems to often "hide in plain sight." Like you intimated, due diligence requires checking the obvious as well as the nuanced.

Your comments about low AFR (as read on a gasoline calibrated Wideband) make perfect sense. When you correct those values back to Lambda and compare to E85's stoich, it correlated well. As for the exhaust backpressure, it is the one sensor correlation that appears to be the most suspicious. Just have to keep my fingers crossed that there is something there, and if not, that the "Rotary Muses" look kindly on us! ;-)

Cheers, Carlos

Looks like we'll know unconditionally by next week if the problem is a electronic control system problem or not. A recently purchase 4-channel PicoScope will be put to good use logging all of the key trigger and ignition signals to unequivocally determine input/outputs and function. If the logs don't reveal any anamolies during the hi-RPM hesitation, then we're moving on to mechanical obstructions or deficiencies. Got my fingers AND toes cross!!

Aaron. Any chance I could bribe you into a picture or two of the new Bosch coils. Already thinking ahead to how I'll permanently wire and mount them before VIR at the end of next month. Keeping the faith!!

Coil itself:

http://i15.photobucket.com/albums/a3...7-09144532.jpg

Coils on bracket resting in engine bay during testing:

http://i15.photobucket.com/albums/a3...7-14110425.jpg

Baby steps!
 

Amazing how much easier thing are with the right tool (PicoScope 4223 Automotive O-scope). Even though I had scoped the ignition trigger output before, without logging it, I didn't have enough resolution to see the problem. First log with the PicoScope, and Paul found a clear problem.

A test of an ignition coil (TF) ECU input trigger, primary coil amperage, and secondary votage clearly shows the misfire rate. The attached picture is just the primary coil winding amperage with the dashed cursors bracketing ~7300 RPM.

Now it's back to the CAS sensor, wheel and wires to hopefully eliminate what should be an erratic trigger input.

That PicoScope is an amazing tool! Would have loved to have it when I was experiencing ignition difficulties..

Planning Tool - Fuel Pump & Injector Spec Spreadsheet
 

Much as "Nature Abhors a Vacuum," my Wrenchin Abhors a Rotary Vacuum. And so I fill it...

The fuel pump and injector planning tool I've been using to assess 044, Cosmo and Supra pump capacity is attached.

Spreadsheet - Fuel Pumps Specs

Hope someone else finds it handy.

Car is fixed! But, spreadsheet won't open unless I get proper crudentials???

Right on Aaron!! Got the good news in the mist of some crappy personal events so it was doubley welcomed.

Anyways, as the old saying goes, "For want of a nail (or wire)..." Guess I did a shitty crimp tying in the tach input to the Lead Coil trigger.

As for the spreadsheet, I've gotten rid of the credentials requirements, so it should be viewable. Please let me know.

Glad it's fixed. The OEM tacho wiring gets its signal directly from the stock ECU, does the M4 not have a spare output that can be used to send a tach signal to the dash?

Scotty, there is an MoTeC tach ignition adapter/expander. However, reading off the Leading coil trigger works fine as an input to our stock tach and saves from using a dedicated ECU output just for the tach.

Per Paul's (and many other professionals) best practices, I will now incorporate a pull-tests on every crimp as a SOP.

"Murphy's" resourcefulness and creativity never cease to amaze me!

Man..... all that head scratching b/c of a bad crimp... Sigh...

Glad you found it. Hopefully the car will be running and driving shortly.

Hy Carlos, I noticed the stright fit on your fuel pump exit line.


I have Bosch 044 (I think you do too) and i comes with a fitting for a Banjo fitting. (side exit) But the banjo fitting piece also has some sort of control valve in it. does it really need that? It also seems to restrict the fuel pump exit...

Iwas thinking about getting a straight fit as well but with thesame size as the fuel pipe (on the tank cover) and fuel line.

did you use a 8 or 10 mm fuel line towards the tank cover?

thanks

Sorry Speedwork, but I'll have to defer to Aaron for question about the in-tank plumbing since i didn't install that pumps. From the looks of it, the orginal Bosch checkvalve may have been replaced with a barbed hose end fitting.

BTW the banjo and checkvalve fittings have come standard on all of the -044 pumps I've ever purchased. I've always thrown away both fittings and replaced with an AN-08 outlet adapter.

Ok thanks for the info :-)

Turbine wheel damage assessment
 

Well, my CYM be-otch won't give me a break. Looks like a lost a front apex seal while on the dyno about a month ago. Best part is I have the log, and there is nothing obvious that might have cause it,. I guess I'll hopefully find out later this winter when I crack it open.

So for now, the first question is what are the effect of this level of damage to a turbine:
- Is it resueable with a few points of efficiency loss and a shorter bearing life?
- Too much damage with >5% airflow degradation; requires replacement?

Sean, Enzo, sure would appreciate your opinions!

From a practical standpoint I'd run it until the engine management is sorted. No point loosing another turbo should the engine let go again trying to nail down your current issue.
Regards,
Crispy
- **NOT A TURBO EXPERT** :)

You can clean it up and use it for now. But it will be off in performance compared to a good one, you may also run into balancing issues if you remove too much material and that will cause premature failure as well, so I would consider it a temporary thing only.

~S~

I've had a turbo shop dress and re-balance a turbine wheel for fairly cheap. It just reduces the risk of the metal fatiguing and tearing. Obviously some performance might be lost, but it will sure save you a lot of money until you get your bugs sorted!

Crispy and Sean, thanks for the helpful, pragmatic replies. I think you're on the money and will in fact use this turbo as a stop-gap until I've sorted out the rest of my setup. Guess the only question is whether it's worth it to "dress and re-balance a turbine wheel" if the turbo will only see less than a dozen hours of use before replacement.

BTW, Sean I'd still like to discuss if I have any option in turbo selection with this short manifold. Will try to call again sometime this week.

Trots, thanks for the heads-up on the potential repairs options.

Nobody to blame but myself!
 

After cracking the keg open, the failure mode was glaring and embarassing... my shitty port exhaust work!!

Looks like when I did the exhaust ported back in 2002-ish, I did't sufficiently bevel the closing edge of the RB-templated exhaust port. The ceramic 3mm eventually must have ripped the chrome off a the port edge, cracking in the process. The associated rotor broke off 3-4mm long chip off the apex seal groove at the corresponding edge.

The only small consolation was that neither side housing suffered any damage.

So my only real question now is whether I want to go back to the 3mm Ianetti's or try OEM 2mm seals...:scratch: Guess I'll have some time to mull it over waiting for Mazda Motorsports to reactivate my membership.

Damn Carlos, sorry to see those pictures :(

Good news is that we've started porting your S8 irons and you won't have to worry about any of this kind of stuff in the future :icon_tup:

Wow Carlos. Sorry to see this but the silver lining is you know EXACTLY the root cause and the associated fix.

Regards,
crispy