i had a rebuild with only 7k miles on it..i did a comp test on it and had no compression on the rear rotor but good comp on the front..i tore the engine apart and found all three apex seals where intact but the apex seal springs were flat and the corner seal springs were flat too and the apex seals where worn more on one side then the other..what could cause this to happen? i need to find out so when i install my new motor the same thing dosent happen to it

 

oh yeah this is a s4 13bt motor

 

heat and time possibly? I dunno.

 

Too much heat. Generally caused by running lean.

 

i had this thing dyno tuned and i had a wideband o2 and never saw it go above 12 under boost...it is possible it went lean once or twice and i didnt notice..a couple people told me that my fuel pump may be going out but its a walbro that i put on when instaled the motor so its almost new

 

Long shot, but did they go in the right way? Opening outward?

 

RA seals? they always flatten

 

12 AFR?

What psi you pushing? If above 12 pounds of boost that is lean my friend?

 

Not really.
You might want to check the oil jet for the rear rotor, since the rotor is primarily cooled by oil. You might also want to make sure the rear rotor MOP jets are working, and make sure the front and rear rotor have the same AFR's... a single channel wideband can only read the average of the two... you could be running lean on the rear and very rich on the front.

 

I seem to recall somebody telling you this is what you'd find inside that engine

IF the seals are rotaryaviation, then they often cause the springs to warp...even if you trash the RA springs and use oem mazda springs. This is another reason I won't use them.

IF you warped the springs with oem, atkins, etc. seals in there then the rotor had to be seeing some very high temps. IT's one of those things that generally only happens on a dyno, or a track car.

 

the seals are 3mm atkins so im not sure if they use oem springs or have there own...i was running around 12 psi during the life of the motor..i had the car dyno tuned and i had a wide band o2 if i would go WOT down the highway my EGT guage would max out at 1600 thats all the further the guage went to so i dont know if it went further or not but when it was that high it wasnt running lean on the wide band..and timeing was set by my tunner..what else could cause such high EGT's?

 

Where is the EGT probe located?

If it's AFTER the turbo, 1600C is too hot.
If you're pegging the EGT gauge with the probe after the turbo, then that's your answer.

Do you know what kinda ignition timing you're using?

What kinda gasoline are you running?


-Ted

 

1600C = 2912F !!

 

Oops...1600F. :P


-Ted

 

im running the stock ecu..im assuming that the timing is set close to stock but i dunno cause i dont mess with that i leave that stuff for my tuner to do..and i was running 93 pump gas..EGT probe is mounted about 8 inches after turbo

 

whats the highest EGT temps i should be seeing at WOT

 

Your set-up?
I wouldn't go over 1400F.


-Ted

 

old setup was SAFC2 720 sec. BNR stage 2 turbo RB full exhaust..setup on new motor is T04R turbo 850 pri 1600 sec microtech lt10 ECU

 

You know what kinda ignition timing you're running at full boost?


-Ted

 

no im not sure...i didnt set it

 

I wouldn't freak out about EGT's. I took my car to Virginia International Raceway back in December and ran it 5000+ rpms for about 20 minutes boosting continuously. EGT's pegged 1600 (probe is in the downpipe), timing was whatever the stock ECU was throwing, and the car ran just fine

 

anyone else have any ideas?

 

Back from the dead, but did you ever figure this out? Did it happen again?

 

bump same thing happened to my friends fc, anyone have more info on this?