Oppai

Hi guys,
Horrible news... my Pink FD is dead...
I took the car out for the first time in about 6 months. The car had Marvel mystery oil put in the rotors before sitting, fuel stabilizer and premix put in the fuel.
Car turned on instantly with absolutely no problems and ran like a dream...
Drove the car about 5 miles (city) for half an hour and then on my way home tried to redline it at about 3/4 throttle at normal operating temperature as you would do with rotaries..
In hindsight this wasn't the smartest idea considering the fuel is 6 months old albeit with fuel stabilizer in it... Go ahead and laugh at my stupidity.

I'm 99.99% sure I blew some seals and ruined the engine due to detonation but here are the symptoms anyway so you folks can help put the nail in the coffin.
3/4 throttle hit 7500 RPM car immediately lets go and stops revving up with my foot still on the throttle, drops from 7500 to 5000 rpm almost instantly
limped the car 1/4 mile home, car struggled HARD to idle, chugging and vibrating like hell at idle and progressively got worse throughout the 1/4 mile.
Both rotors sound the same, issue is not localized to a single rotor
By the time I got home, car shut off 3 times just trying to back it into my driveway and also had lots of trouble going into gear.
Cranking the engine after getting home the engine sounds like it makes absolutely ZERO compression in both rotors on all faces. No weird clinking scratching or rattling noises that I can make out.
Obviously the car won't turn on..

In the NYC area, probably going to call IRP for a rebuild or swap.. any input would be appreciated.

Howard Coleman

iTrader: (6)

sorry to hear about your motor. i don't know your engine but if you have the newer aftermarket apex seals and had detonation the most common failure is corner seal springs. many of the newer apex seals often don't break. corner seal springs, when faced with a doubling of combustion chamber heat to as much as 3500 F, flatten. while this may sound like a "so what" flat corner seal springs drop compression about 40%. if you have OE apex seals or Atkins you will have broken apex seals. of course either way the motor will have to come apart.

broken apex seals generally score the rotor housings and gouge the rotor. and on the way out ding the turbine wheel.
collapsed corner seal springs just require replacment. specify ONLY stock FD corner seal springs which are made of inconel.

Oppai

The engine has definitely never been rebuilt before stock everything, 55,000 miles and was making around 87 +/- 5 psi compression in both rotors on all faces before failure. I guess probably broken seals as you say. Unfortunate.. hope the rotors and housing are salvageable but not really holding my breath for it. Drove it 1/4 mile home after the catastrophic failure.

Testrun

Sorry to hear. I know that is a horrible feeling. Have you pulled a plug and verified no compression?

Oppai

No but the plan is to do it soon and stick a borescope in there to see if my motor needs replacing to avoid the labor cost of having IRP doing it for me
Still debating if I want to do the swap myself or drop the car off let IRP take care of everything.
The major pain point right now is I think the detonation could have been caused by the aggressive tune that was on this car on it's weird japanese "eco-cpu" tune which uses EEPROM to store the maps and from what the owner of the company that makes this ECU system said there is no easy way to get engine data logs out of it.
With this being known, I'm not sure it's worth it to just do an engine swap because I could find myself running into the exact same issue down the line with a new engine...

I also can't adjust the tune for a new engine which is definitely a no-go. Nobody stateside knows how to tune this silly thing.
Even if somebody knew how to change the map values nobody here in their right mind tunes these motors without looking at any engine logs.

Furthermore, if the turbos are also damaged as Howard pointed out is likely, that will be an additional major expense.
What I'm looking at to do this right is.... Brand new engine, Standalone ECU & Harness, single turbo setup...
An absolute gargantuan expense...

Oppai

If anyone has a ballpark to how much parts cost and labor cost would be to do:
EFR single turbo 325-350 whp setup
haltech 1500 + harness + tune
fresh mazda motor

Price to do it all in one go would be much appreciated. Just trying to figure out my options right now and if it's worth it to try to bring it back to life.

DaleClark

iTrader: (55)

OK, first off, take a DEEP breath.

Chill out.

Take a week off from the RX-7 and do something else.

Blown engines happen to everyone at some point. It's not the end of the world. There are tons of options and tons of ways of tackling this problem.

My first engine I blew in my '88 turbo back in the day was heartbreaking - I was a broke college kid living on credit cards. Ended up selling my desktop PC and some other odds and ends, bought the parts, rebuilt myself. Screwed up a TON of stuff but I learned a lot.

All that said, I would first off define what you want to accomplish with the rebuild. Obviously you want to get the car running again, and you want it running right so it stays happy for a long time to come.

First, the engine. You can go with a new Mazda engine from IRP, they aren't too pricey all things considered, around $5000 for the short block. Get the appropriate gaskets and hoses for a quality leak-free install and there you go. If the turbos ate an apex seal or two you can get a good used set, get some new 99 turbos, or get BNR's. You've got lots of options.

That ECU isn't going to do you any favors in the long run - it's cool, but obviously it let you down. Get a PowerFC and get IRP to tune it for you. They can have it tuned and rock solid reliable and driving awesome.

Of course the next factor is if you want to go further than that - single turbo, built/ported motor, etc. Also it depends on how much you can do yourself and how much you want to have a shop do.

Again, breathe, relax, it's OK. It sucks but it's not the end of the world. Figure out a budget, make a game plan, and move forward.

Dale

Oppai

Thanks Dale I really appreciate the support
I've already blown up a 13b MSP before so this didn't hit me too hard although still pretty disappointing.
At the end of the day it was me being stupid that blew up the car so there's no point getting too down about it.
I'm sure the folks at IRP will take good care of me, but one side of me feels I should fix the mess I made myself. The other side of me feels I should let the professionals do it right.
Lots of busy weekends in my future..

I completely forgot about the Apexi PFC option which for sure would be much much cheaper than going haltech. Thanks for reminding me--

F1blueRx7

iTrader: (5)

I really recommend putting a rotary compression tester on the car to clearly define the failure before you do anything else. Then, the faster you get the engine out and open, the less it hurts. Speaking from very recent experience, turn the anger and anxiety into motivation.

Oppai

Yeah I just needed to get away from the car when I blew it up like Dale said. The plan is to hit it with a compression test and a borescope next weekend to see if the engine is salvageable.

DaleClark

iTrader: (55)

Really a borescope won't be able to tell you much. Run the compression test, if it's bad, there you go. Most times you lose 1 rotor and that rotor and rotor housing are junk. At this point the damage is done, borescope won't really give you any information that helps anything.

Dale

Oppai

If there's horrible chatter marks wouldnt they show up on the borescope? Was figuring if both rotors/housings are trashed on the borescope I'd just get the order in for a fresh engine before even taking it apart.

IRPerformance

iTrader: (41)

Sorry about the bad luck. If you need help give us a call at the shop and we will take care of you. Any time a motor goes I like to go through the car and find what caused it so it doesn't happen again.

DaleClark

iTrader: (55)

More of a case of if one rotor has bad compression and the other is OK then you know what's up. If they are both low it's trashed.

A blown apex seal typically shows as 1 high compression pulse and 2 low - like 20/20/90 or something like that.

I guess the thing here is if you are looking at getting the motor rebuilt. But, you really can't say "motor will need x, y, and z parts" by a borescope - first it's hard to see everything you need, you can't see the water jackets, you can't check the rotors for wear in the apex seal slots, you can't check step wear on irons, you can't check bearing wear....best case you may be able to see a scored rotor housing, but it will be hard to see and the compression test will probably tell you that answer anyhow.

In other words I wouldn't spend time and effort messing with a borescope when you aren't going to get any more knowledge that a compression test can give.

Dale

Oppai

Got it, makes sense. I will go ahead and perform the compression test first and pass on the borescope.
Went over some estimates with IRP--
A rebuild isn't going to be feasible unless I do it myself as the costs end up coming pretty close to buying a brand new motor from them.
I think the game plan for the time being is going to be send to IRP for a full swap if that's what the car needs, then rebuild the old motor in my own time mostly for learning purposes.

DaleClark

iTrader: (55)

Nice, sounds like you got a solid idea there.

I would try and make a hard list of what you want with the new motor. It's VERY easy to get into "while you're in there" and you end up with a never-ending and always-spending project.

Personally, I'd get that reman in there, get a PowerFC in there tuned by IRP, make sure the twins are good, new gaskets and hoses, and call it a day. You can be easily at 300-350hp with a good twin setup that will drive sweet and be a ton of fun and it won't break the bank.

Going single is great and you can make some serious power, IRP has some killer single turbo setups, but be mindful that going that direction leads to a lot more stuff - bigger intercoolers, bigger fuel, bigger clutch, bigger brakes, etc. etc. etc. It's easy to triple the cost of what you would have spent to get the car running.

Remember no project car is EVER done. Don't feel like you have to do EVERYTHING "while it's in the shop". Get it running, you can always go back and upgrade other things down the road and it's a lot easier to go from a position of a car that starts, runs, and drives and do some modification or upgrade on it.

Dale

Testrun

Very good points on here.
No one knows your budget. Most economical imo is drop in a new crated motor. You could open it up and swap Apex seals if it will make you feel more fuzzy inside for the possibility of detonation in the future and If you do that you could consider porting as the motor is already open. Throw on some new "sp" twins. The SP are suppose to be good for another 20-30HP and the efini turbos sp or not can handle higher boost. Are generally more durable. Pfc, tune, and water injection. As Dale stated...easy 320-360 HP. I am around 350-360 with negligible knock, very conservative timing, and 13.5 - 14psi. This thing is quick. I am pleased. Everything is new, I stayed twin as it was designed to be (just with an extra 130-140 HP to the wheels), saved a lot of $$ which went to other upgrades like new water pump, radiator, sensors, bushings, belts, 4.44 gears..., whatever.
Or go single. If I went single I would be searching for serious power. 400+ for sure.
I was going to keep and rebuild my old motor, but I needed to many other things while I was "there" so I sold it to offset the cost.

Just do your research about seals. There are always trade offs with everything.

Water injection is a must imo.

DaleClark

iTrader: (55)

BTW there's more to just swapping the apex seals on a Mazda crate engine. Since you have to open it up, you have to re-clean everything, get all the RTV off, you may need to replace water seals and dowel pin O-rings.

In other words there will be some parts costs involved and it needs to be done carefully to make sure the motor goes back together properly.

Dale

shawn1331

Word to the wise I wouldn't bother with a pfc. I lost an engine due to a pfc not having ANY engine safeties. For the few hundred extra to get the haltech/adaptronic do it abd save another engine

Testrun

Apologies as I thought this was obvious when I brought up porting.

Testrun

I am curious as to what safety features your speaking of that could have saved your motor?
When I started looking I to the Haltech it was well over a "few hundred" more for safety features.
You can add some "soft" rev cuts on the pfc (retarding the timing) and use an aftermarket boost cut with a failsafe afr. Not sure if it will be quick enough, but I don't think it would be quick enough on the haltech either.

IRPerformance

iTrader: (41)

While base pricing for a Haltech initially seams to be not much more than pfc, by the time you add the sensors, harness, and other options it adds up fast. Running a better ecu with a 27 year old harness and sensors doesn't give much benefit. Second, it will only be able to read what the stock ecu can unless you add the options. At minimum you should be monitoring coolant temp, air temp, boost, fuel pressure, oil pressure, afr, and knock.

Testrun

My quote was another $1500 on the Haltech eith adequatesensors.... That's a lot of $.

shawn1331

My engine died due to knock that the pfc didn't do anything to control. Its not a guarantee that a modern ecu would have saved it but there is a good chance. I believe a link and I know adaptronic allow for oil pressure, knock, fuel pressure, water over temp, and afr safeties with out adding on much of anything you don't already have (assuming you have an afr gauge, the oil and fuel sensors are about $100 a piece give or take)

Link and adaptronic i believe are around 1300usd brand new. I agree with Ihor though that if the harness is in bad shape the ecu can only do so much. Personally I would put a link plug and play for similar price of a new pfc.

DaleClark

iTrader: (55)

The Haltech is newer than the PFC. It has more features, can be easier to work with, has safety features. Does that mean you will never blow up a motor with one? No.

My rule of thumb - car with stock twins and bolt ons? Power FC all day long. It's easy, it's reasonably priced, it does the job great, there's tons of support for it. Going single turbo and/or chasing big power? Haltech. You're going to have more work cut out for you and you're going to need a lot more money as well but there's more flexibility.

I see this on FB all the time, people bashing the PFC and saying "you gotta do a Haltech". I bet 99% of them haven't touched a Haltech (or a PFC). The PFC has proven itself over and over again as a good computer. You can blow up your engine with either setup - "safeties" can't account for everything.

Dale