Wow. Bad news. At least you got some good people scratching their heads over it.



Sounds like the merging of results of multiple variables over time.

Hey I appreciate you reading the thread and I am still desperate for an answer. If you have any Ideas Please feel free to input.

You did this all by yourself? Very impressive;)

I would like to add that "ccarlisi" has been invaluable. This is not a one man job and Chris has taken his time, driven up from Boston and spent many hours of his time researching and working on my car at no charge. Many in the rx7 community have also given of thier time as mentioned above. I could not have done this alone. Thanks Chris, Sean, Steve, Judge ITO, and Demitrious.

There are people who I am probably forgetting but everyone has been helpful. I am confident all these great Rotary minds will help me solve this issue.

This problem we are having with Mike's engine is a serious pain in the ass. Before Mike brought me the engine the car was being worked at KDR and had some engine problems over there. I built this nice engine for mike and KDR installs it. I tell mike to bring me the car over so I could go over it(check ignition timing) sure enough the trigger wires to the crank angle sensor was inverted and the engine timing was too advanced causing problems with his other engines. I fix that problem and told mike to break his engine in. Before when the car was at KDR the engines were breaking apex seals from detonation(timing was to advanced from inverted sensor wires) this time on my engine the apex seals warped. Basically the seals overheated and curled up in the center and looses connection to the surface of the rotor housing causing a loss of vacuum and compression.



Later after some more searching into mike's car I found a problem with the secondary injector harness. I fix that problem, rebuilt the engine and again after some dyno tunning the apex seals warped. I do some more research. I blue print the engine. I mean I measured every single part of the engine for bad rotor houisngs bad rotors and fine every single part with in specs. In my years I have seen apex seals warp and curl up when the engine is running super lean and creates more internal combustion temperatures then what the apex seals are built to take. If the apex seals heat up past a point they will warp.



Know addressing warped apex seals. I talk to Steve kan and he told me that the engine seems to be needing more fuel then normal and that the front rotor was running leaner then the back rotor. some corrections was done to the power fc and the balance between rotors was better.( this could have been the cause of a bad primary injector) Steve told me that the tunning was very weird, that other cars with this type of fuel being pumped into the engine would not even run but mike's car was fine. clearly there is a fuel problem but where?



I talked to JIM Mederer from Racing Beat to pic his brain, and he told me a couple of scenarios.

1) fuel mixture to lean will cause high exhaust gas temperatues(we already know this)

2) not enough pre-mix(bad metering oil pump)

3)oil temperature to high and will not cool off the rotor's and transfer heat away from the apex seals.

4) after market secondary injectors may have a fuel spray pattern that will not flow in a suspended state into the intake manifold. If the wrong sencondary injectors are used the intake manifold walls will get saturated with fuel and cause a lean condition and elevate combustion temperatures.

All I could say is that I have tuned and seen engines run at 15 to 44lbs of boost and apex seals are not warping like mikes engine at 13 to 15lbs of boost. In mikes car we have a serious bug and I feel is fuel related. (not enough fuel via bad injectors high or low impedance problem with the power FC) I too want to get to the bottom of this problem and learn from it. I will not want this to happed again. The power FC is in question now.



And yes the rotor housing exhaust ports are beveled. Let's not forget I started that whole thread.

All I can say is good luck guys. You definately have the right guys searching for the problem

Wont too much fuel cause high EGTs? Maybe an injector is leaking.

do you have resistors on the pfc? the 1600's are @about 5ohms, they need to be brought up to 12-15ohms.



secondly, you may want to check the oil temps, maybe the thermostat in the oil cooler died? i know ive never seen that but you're now looking for wierd stuff, imo

The pics above look like the apex seals were rocking in the grooves.

This is typical of too much clearance on the apex seal groove (highly unlikely), inadequate apex seal lubrication (are you running pre-mix or stock OMP?), or detonation (causes the seal to chatter along the rotor housing surface)...or all of the above. :(





-Ted

We have been using 3ohm resistors on the secondairies but we have mixed opinions about them. Some say they use them with the PFC some say they dont. Some say the resistors can cause a lean condition that happens so fast the Wideband wont pick it up. Also that the 1680cc inj change thier current needs as they warm up. All very confusing. I understood that you needed the resistors as to not overheat the inj driver (chip) in the PFC.



RETed, Thanks for the reply. I had hoped to get your input.

The clearance on the motor was done by ITO and i believe the tolerances might be a little greater but i dont know on what parts. Maybe Ito can answer this one. Is this whats meant by Race clearancing? Also i would like to add I get massive fuel in my oil and the crankcase is being pressurized by the cumbustion pressure.

Ted, can we narrow down this list by taking into conisderation the fact that mike only has this problem at 13.5psi+ We did a bunch of pulls at less than 13.5 without incident, but as soon as we hit 13.5 it starting losing vac with each pull.







I think it's important to note that Steve said the variance between the front and rear rotor would normally be considered insignificant, but he decided to correct for it only because we asked him to be extremely careful with every aspect of the car's tuning since mike had already gone through a couple motors. I was the one pulling the burning hot plugs after every run :-p. The front plugs were less damp than the rears, but the variance was minor.



Also, Steve's fuel comment is slightly misleading. His point was that the car ran ok with an extremely rich AFR on the wideband, not that it ran ok with extremely high duty cycle settings. Just to clarify, high duty cycle settings were not needed to get normal/conservative afrs.

The variable list to date in no particular order (culled from the messages):



1-secondary injectors

2-primary injectors

3-front to rear rotor lean condition and being corrected in PFC (usually the REAR needs the extra fuel!)

4-crank wire trigger wires being reversed

5-caca map (at one point in time too much timing)

6-secondary injector harness

7-OMP / pre-mix issue





Could somebody add what I missed? Just trying to get a clear picture.



Questions:

Oil pressure behavior at 13.5psi versus other times? What is it reading?

Oil temperature behavior, too?

The apex seal to rotor groove clearance is .002 of an inch. .002 is ideal for rotor tip to apex seal clearance. 002 is nice and tight in the groove for good sealing compression but enough room incase the metal on the rotor tips tries to expand(grow from heat) and not jam the apex seal in the rotor groove.

cas wires and sensors? is this the original engine harness?



has anyone verified tdc on the engine vs the crank pulley?



send the injectors to be flow tested?

We put a brand new factory main wiring harness in the car before the last motor got tuned. As I believe Mike said before the timing is accurate (or at least consistent) from idle to redline. Not sure about the TDC thing, maybe Ito can confirm that.

1-secondary injectors



Secondary injectors as well as primary inj were sent to RC engineering to be flow tested. The pri were dirty and were cleaned. The sec inj were odd balls and suggested we replace them with equal units.

I in fact bought 2 new 1680cc inj and ITO installed them.



3-front to rear rotor lean condition and being corrected in PFC (usually the REAR needs the extra fuel!)



Well this was a marginal change in fuel but was noted as there is no aspect of this tuning i want to omit. The Break -in plugs were white but the car was carefully broken in with only vac driving and the car rolled up onto the dyno with great idle VAC. As soon as Steve adjusted the map the idle vac went to -15 inches. Best i've seen on this motor. It also sounded fabulous. Pulls were made on the wastegate spring at 10 psi and the map was set up for very rich air fuels. There wasn't a dry eye in the house. It def wasnt burning it all. Everyones skin and eyes were covered with Fuel. Very nasty. Oh the burn and tears. It was so rich it was spitting out fuel and flames were showing out the pipe. Fuel pressure was steady and Air fuels held on wide band in the 10's and Duty cycle on the inj low to mid 80% max.

Im skeptical the car needs more fuel but i am willing to entertain any ideas toward progress. The fact the car is running lean with this fuel set-up doesn't make alot of sense to me. The car could run on stock fuel sys at 13 psi yet I have alot of upgrades that all my friends use with even up to 500 RWHP with no issues. I put down 350rwhp 13.5 psi and the motor was failing. Fuel issues usually show up on pressure gauges, if not pressure then elevated duty cycle on Inj due to volume loss. The one issue is the resistors and im temped to yank them just to eliminate the possible problem. Just want to make sure it wont fry the PFC.



4-crank wire trigger wires being reversed



This happened on the very first motor. the car had very high coolant temps 106degrees on the PFC. I got to ITO's and he found the problem and fixed it. He could hear the car running rough and put a light on the crank and sure enough the wired had been crossed. he fixed the issue. The motor had about 50 miles driven on it with the crank angle sensor wires reversed. The harness was replaced before the 3rd motor was tuned and the timing verified at idle on the dyno before tuning.



5-caca map (at one point in time too much timing)



This was also something ITO fixed when he fixed the Crank angle sensor. John Dewer (sp?) fixed the negative split and made sure the map was safe to drive till tuned. Ito was there supervising.



6-secondary injector harness



This had seemed to be a problem with motor # 1 but with # 2 Ito had fixed it # 3 Chris and I replaced the entire engine harness with a Brand new OEM harness and I soldered the Resistors myself. I have done soldering before and i did these fine. I took extra care.





7-OMP / pre-mix issue



Well The OMP seems to be working ok, i have also added premix and the car is stumbling all over itself at idle. Smokes alot due to premix and OMP combined. Also so far this issue isnt consistent with OMP failure. Also the Oil temps don't seem like a problem because there is no Apex seal spring flattening, no bearing wear. No elevated coolant temps to indicated higher oil temps. No chatter marks on the housings from Apex seal springs loosing tension.



Oil pressure is very high. I see higher pressure due to ITO installing Racing beat Plug. doesn't seem out of the ordinary except for crankcase being pressurized by Combustion

it might do that. i know of one pfc that popped due to no resistors.

So has anyone actually measured the resistance of the injectors?



Some injectors are sort of "medium impedance" - I've measured ~5.2 ohms for some large injectors. Adding a resistor to those might be a problem.



If the PFC has requirements for injector impedance, be sure to heed them. Don't put low impedance (~2 ohm) injectors on a saturated driver - either the driver or the injectors will die quickly.

thats right the 1600's are like 5ohms. i think its right on the edge as far as keeping the pfc alive. i believe the pfc has a 1 watt chip



ah its 3w https://www.nopistons.com/forums/index.php?...&hl=6+injectors

Okay so that's 3 watts total rating for all 4 drivers. I wonder if Apexi has ever heard of a "heat sink". sheesh. So if your 1680 cc injectors are 5 ohms (measure this!), this would be ~3 amps, with 0.25 ohm FET "on" resistance is 1.25 watts per secondary injector. You sort of have to work the duty cycle in there, but this is the

upper bound. Primaries (high impedance) would come to about 0.25 watts each.



Total is then 3 watts @ 100% duty cycle for 2 "medium impedance) 5 ohm secondaries (no resistors) and 2 high impedance primaries. This looks to be within spec, but remember to check the resistance of your injectors to verify.



Also it's a good idea to make sure your fuel pump is getting enough voltage.

You need to check the voltage between pump+ and pump- as close to the pump

as possible. Checking pump+ to chassis ground is not valid as it does not

consider voltage drop across the ground wire.



Finally, I know this is silly, but check the fuel filter.

DOH! MATH ERROR!



So it comes to 5 watts total at 100% duty cycle. Sorry about theat...

At 60% you're within spec (and it actually takes ~ 1ms for an injector

to pull max current)



That being said, you _might_ get away without resistors on the secondaries,

but it's risky.

83,



Mike's fuel pressure was rock solid. I watched a fuel pressure gauge during each run because this was something I was concerned about. If the pump was going beyond its volume capacity his fuel pressure would roll off at high rpm as the volume requirement increased (or not increase with each lb of boost)



The supra pump is rated at 225+ L/hr at 70psi at 13.5v.

At 85% duty cycle with a total fuel pressure of 70psi (15psi boost+40+15 line restriction) that is enough fuel for more than 480rwhp with headroom. If anybody is unsure of this, use Maxcooper's fuel system calculator. I did this and looked at the pump dyno sheets before deciding on the supra pump. It's one of the best pumps you can get for this car. It significantly outflows most of the walbro pumps at equal fuel pressure. Bottom line is Mike has the capcity for 480rwhp.



Given that he is running into problems at 350rwhp@13psi when, according to the test data by RC engineering his pump has enough capacity for 490rwhp at more than 15lbs of boost AND

his AFRs are extremely rich AND

his fuel pressure is holding at the set valve, AND

there are several people producing a lot more hp using the same fuel system without any problems, I would be extremely surprised if his problem was fuel related.



The injector resistors could be an issue, but again, there are many people using these injectors with resistors (myself included). Mike has gone through two sets of injectors with two different kind of resistors and it has had no effect on his problem. What are the odds of what is described to be an intermintent problem at best occuring every single time the car is boosted to 13.5psi on the dyno with two different sets of injectors?



Step back and look at all the INPUTS and OUTPUTS

INPUT:

timing: the map is conservative, I've checked and rechecked for anything funky such as negative split.

Fuel: fuel pressure has been confirmed, the injectors have been flow tested, the harness is new

Boost: 3 seperate boost gauges confirm the MAP sensor is accurate.



OUTPUT:

afrs: 10.2-10.8. The car was actually stumbling at times because it was so rich. We know the plugs for each rotor look the same and are both WET.

egts: ???

Timing: verified all the way to redline-the motor is getting the timing the ECU is set at



Conclusions/items that I for good or bad have ruled out:

Fuel: The car is setup to run rich and the outputs indicate that it is in fact running rich.

Timing: The timing appears to be accurate



What's left

-extreme oil temp: doubtful given that the problem seems to correspond to BOOST and the dyno runs are short. Also, according to Mazdatrix high oil temps cause chatter marks on the housings, which Mike does not have.

-lack of oil metering: Maybe the metering pump is worn and cannot fight against the positive combustion chamber pressure at 13.5psi to meter oil in. However, I've spoken to several drag guys that don't meter oil in or run premix. Apparently, it wears down the housings but doesn't have much of an impact on the seals.

-bad seals: doubtful because he's used both 2 and 3 piece mazda seals.

-clearancing: I don't know much about this so I can't say

-exhaust porting: too wide?-again not my area of expertise

-bent E-shaft? a track guy I spoke to suggested this

I think the problem has something to do with the ported motor because the problem did not start until he got the motor ported. He lost a few motors under the supervision of KD before that, but they weren't losing compression on the dyno, they were detonating and at higher boost. The last stock motor he put in got off the dyno without a problem and then blew a rear seal on the street a few weeks later at around 16lbs of boost. As Ito mentioned, this was probably due to the fact that KD wired up the crank angle sensors wrong. Remember, Mike was making 400rwhp with the stock motors (about 50 more than he is making now) and didn't have any fuel related problems. Ito obviously knows how to build a motor and has a good track record, so I tend to think the cause is a defective part rather than worksmanship.

Air/water/fuel temp sensors and wires okay? Just a thought.

I know you covered "what happens without metering oil", but I'm wondering if

being that overrich is washing oil out of the motor and causing problems? (like

the crankcase pressure)

Ito mentioned 0.002" - that's perfectly fine.



Resistors on fuel injectors shouldn't affect anything.

If anything, reaction time (or fuel injector dwell time) induced by the resistors should not affect fuel injector capability with much significance. We've messed around with fuel injector crossover phase-in, and the engine can absorb a slight lean condition (easily seen on any O2 sensor - narrow or wide) without much fuss. If you do not see a lean drop on the wide-band, I doubt anything weird is happening.



Now, this leads up to the "1600's"...

I got a heads up from Paul Ko @ K2RD that some of these 1600's are blueprinting at very widely ranging flow rates. I've heard anything from 1100 to 1800! The dual EGT set-up will confirm this right away. The "cheap" way to confirm this is to send them out to get flow-benched.





-Ted

Interesting, but do you really think this could happen on both sets of 1600s?

Also, why didn't the non ported motors fail the same way with the same injectors producing more HP?

Where is fuel pressure being measured? You might want to try checking it

just before the regulator, in case there is an obstruction in the line. (I'm assuming

it was checked sort of upstream, given the 15 psi system loss noted).

Fuel pressure is being measured on the regulator. Also if there is an obstruction Wouldnt the Wideband show the lean Air/fuel ratios? Also the car NEVER detonates.

We only run this rich now due to the Cars problems. We originally ran in the low to mid 11-1 range for air fuels with same issue. Also car has a brand new factory harness before this last motor was dynoed. Wires are all new.

a couple of things



fuel: it seems to be rich, you might want to use a couple different wb's, or actually record the fuel consumption on the dyno (our its car is very roughly .80 bsfc @10:1afr stock ecu and about .72bsfc at 13.5:1 afr, same hp level)



i think you'll find that it is rich and can eliminate the fuel system as a cause



ignition: maybe verify that t1 and t2 are correct (prolly they are), maybe try a different leading coil?





or actually we need to back up a step; what makes apex seals warp? heat? pressure? why does this happen at 13psi? is it ok at 12? what is different at 13?

3 different widebands were used. All showed proper air fuels.

As far as the coils. Well Anything is possible. Usually if a coil is firing wrong its due to the Coil driver on the ECU. If the coil driver gets stuck on for instance the coil will overheat and crack/ fail. Also the car wont run right, car seems to run fine besides the melting seals and crankcase blowing oil out dipstick.

First off sorry to hear about your troubles.



Here is what I would do going from here...



I would definitely try another PFC to make sure it is nothing with the ECU.



If you cannot get another power FC, I would then change the injectors back to the stock ones and run the car with a stock computer with race gas and higher fuel pressure than normal (just to be safe) Your A/fs should be safe.



I would go this route now since when you get the dual EGTs, if the readings are off, you will probably do some of the same things.



If that does not work, I would spend $1800 on a dealer reman and install it for testing purposes. I personally have seen Judge Ito's work and he is very highly respected in the rotary community, maybe something/somewhere has a hairline crack that will spec ok but will open up under boost etc.. (just speculating)



If the issue goes away after installing the dealer reman I am sure you can easily sell that motor for $1500 and replace the defective parts on your current motor. This way it will only cost you $300 plus whatever the installation was.



I am not a rotary specialist in any way but this is what I came up with. I just nextelled Rx794 to see his thoughts, he should be posting when he gets home. He might have some more ideas on where to go with this.



It should all work out soon, you will probably look back at this and laugh after your first 10sec pass https://www.nopistons.com/forums/pub...IR#>/smile.png



Anthony

I have ported many engines similar to mikes engine using a similar set up like mike's car. from power FC to 1600cc's injectors to the same fuel pump and regulator. And no problems what so ever. One car was even tuned by Steve Kan with no problem. I have also seen stock engines lean out and warp apex seals. The problem here is the melting of apex seals. when an apex seal warps there is a reason behind that. I have melted apex seals with racing engines and every single time I hurt an apex seal it was due to a lean condition. I know this because I pulled fuel out purposely to try to gain more power and I ended up paying the price.(warped apex seal) I just can't figure out why mikes engine is seriously warping seals at such low boost with conservative a/f ratios on the wide band.

Has anyone checked to see if fuel wasn't leaking from anywhere outside of the motor, OR if the rail was limiting fuel to the injectors from any improper machining facing the feed side of the injector(s)? This is the only new thing I can think of other than what's been already stated in this thread as to what could be leaning out the one rotor more than the rear, remember a wideband will ONLY show you a COMBINED A/F ratio of BOTH rotors combined, NOT each chamber. I'm only stating this because you keep saying that 1 rotor is giving you more issues than the other one, and the only reason that you would get seals to warp is from them overheating(lean). Hope this helps, it's the only thing I could think of.

Just to add to my post, remember you said that the tuner tried to add fuel to one rotor more than the other one, and nothing happened, which leads me to believe that something is blocking this from happening.

True, but since his combined AFR is so rich, one rotor would have to be extremely rich for the other to be running lean enough to cause damage. Given that the motor was stumbling when the afrs got down to around 10:1 I doubt it would be able to run if the split between the rotors was extreme enough to cause damage.



I put together a spread sheet to explore this further.



Here is the formula I used:

overall afr=(rotor1+rotor2)/2

overall afr * 2 = rotor1+rotor2

(overall afr * 2)-rotor 2 =rotor 1 afr

With this equation I can set the overall afr to whatever I want, enter an afr value for one of the two rotors and it will return the afr value for the other rotor. I hope someone will jump in if my reasoning is off.



Here are the numbers I got:

overall:--rotor1:-- Rotor2:

10.5--------10----------11 not lean enough to cause damage

10.5--------09----------12 doubt it would run with afr of 9

10.5--------8.5---------12.5 Even less likely to run and the afr on #1 is still not that bad.



While we're on this subject, what AFR can melt the seals?





Re the tuner adding fuel:

We noticed a slight variance between the dampness of the plugs. Steve initially overcorrected and then brought it back to a near even split. In the end the difference was not something significant enough to warrant concern under normal circumstances. Regardless, the system was always responsive to adjustments.

One more thing to check is timing advance under a load. The engine is running negative timing at idle and positive timing under boost and light crusing. If by any chance the power FC is running a negative timing under a load(boost) the egt's will go up and cause the seals to warp. Next time when the car is on the dyno and making a light pull somebody needs to varify with a timing light for timing advance. If the engine does not advance timing and stays in a negative timing, this will be the reason for loss of power and warping seals. I have not been to any dyno sessions with mikes car but I'll be there for the next one and would like to try and help with this problem.

The more I sit here and think about it. I'm almost sure the car is having a timing issue. Not enough timing will cause egt's to go seriously high and damage seals. Since proper fuel pressure was checked, injectors cleaned and balanced proper fuel pressure under a load. I going to say timing needs to be addressed with a timing light under a load.



High egts will melt apex seals. High egts come by easier with not enough timing then a lean air fuel mixture.

Mike I remember you telling me the turbo melting due to high egt's I think we might have found the problem. I have also played around with negative timing on the race car and seen a faster apex seal damage(warping) then damage from a lean condition.