I'm thinking
make all the other changes but run with the Mazsport coils being very carefull about backing off at the first sign of a misfire . If the problem is still there - then replace the coils and retry . That way I'll know for sure

 

yes, because risking your new engine is worth finding out if it's the coils.

 

but am I actually doing that . I did read that Detonation - preignition etc that would kill an engine is not caused by weak coils anyway ......

 

all I can say is that my car ran fine before these coils. Once I installed them the car ran lean and something wasn't right. I brought the car to mazsport, they checked the connections then retuned it. I had detonation on the drive home. If Scott can't get it working, I have no faith in them.

Ultimately I don't think it was the coils, rather, I think it was the tune. Something wasn't right, but this is all speculation. I'd rather err on the side of safety than risk a second engine. Your money though.

We had this exact same discussion just before you went turbo, and this was my recommendation back then too.

 

BTW, with the advances with tuning on the rx-8, I would recommend FI to anyone that asks. Just make sure you have the accessport, a good tune on it, and a proper flowing intake so the MAF is happy. There's no more reason for engines to blow anymore unless you're playing with fire (too close to the edge).

 

I couldn't make that connection either - what has bum coils got to do with either pre-ignition or detonation?

Unless the allegation is that bad coils produce sparks at the wrong time, I don't see the connection - the worst that could happen is no spark, right?

S

 

One more time for the nose-bleed seats:

If you have a LEADING coil failure or misfire, such that only the TRAILING produces an ignition event, you can - and probably WILL - have a massive detonation event, especially at or around the torque peak.

In other words - trailing ignition only = snap, crackle, pop.

I don't mean to beat a dead horse, but "tested and proven" apparently has a different meaning depending on who the vendor is.

 

ouch - the front of my teeshirt is looking gruesome now.
Just a thought from a nose bleeder :
If your leading did not fire - wouldn't your trailing going off 15 degrees later just be a little retarded . Just trying to understand .
I always thought over advanced ignition was more dangerous .....

 

The trailing is following the leading by 15° of crank rotation, but think about where it is located physically in the housing relative to the forward motion of the rotor and the charge pocket.
Now, imagine if the whole charge is lit from back there instead of on the leading edge of rotor motion.

 

OK - here is the damage

One of these apexs is not like the other


Bits of apex make a nice gouge in the housing ....

 

suck

 

Don't worry it is supposed to be like that....

 

/\ say what ?

 

Sarcasm.... FTL?

By the way - got a notice your Int-X showed up; have to sign for it; I'll get it tomorrow.

 

cool - good luck with it .

On the positive side - the rest of the motor is in great condition .
The builder says I dont even need bearings ....

He is also pretty sure that detonation caused the failure

 

Corner piece - exit,stage left.
That is usually what goes.
It didn't gouge the housing? If not, you are lucky.

 

yes it gouged the housing - about 2" long by a good 1.5mm deep

 

You usually don't unless it is REAL high mileage.

 

I'm imagining but I still don't see it.

 

The whole charge is not uniform; there is a higher concentration of fuel and air by the trailing plug (richer mixture) due to the sweeping motion of the rotor; then as the flame propagates out toward the leading plug - this takes a long time in our chamber - heat and pressure are pushing out to this leaner mixture (faster hotter burn); it will not be a smooth flame front consuming everything. Most likely the heat and pressure will cause the mixture in the leading area to explode uncontrollably = detonation.

 

 

ouch so do you need new housing ? what about the rotor it self ?

 

rotor is fine - no sign of damage . Housing is now an ornament - needed one to compliment my rotor clock so isn't that lucky ...

 

what's the ETA on the rebuild?

 

possibly this week depending on if parts are in stock - still waiting for the parts list