I ran stock boost, front rotor blew with less then 3k on new engine. They blamed it on the PFC with stock map and street port, but the plugs were not white, they were dark brown on one and oil black on the other. The only other factor was the ACV had disconnected. They gave me the possiblity of side seals failing but without opening it up, I won't know and may never prove since i'm still driving it. I need to do two races for the Mazdacomp membership before I tear it down so I can can some discounts. My finish place or time does not matter as long as I complete. There was no bang, no noise other then a woosh, woosh, woosh, like the seals just fell out. This was the 2nd time I opened her up. The 1st at 6krpm but this time I hit 8k with a possible peak of 8.2krpms. Boost was at 10lbs and on the 6k run it never creeped nor spiked but without a recordable gauge or datalogic, I have no proof of anything. I don't want to blame someone for something I did but at the same time I don't want to be blamed for something I didn't do either! Oh, eccentric shaft/front cover bolt was never torqued down. I did tighten it when I found out but my torque wrench is inch lbs and not foot lbs (D'oh). https://www.nopistons.com/forums/pub...O_DIR#>/11.gif



stock twins

Apexi FMIC & intakes

Apexi PFC w/stock map

HKS DP

Border Racing Burnout Exaust & Hi-Flow Cat'

Stock injectors (cleaned before install)

Stock fue pump

boost = 10lbs (PFC controled)

Street Ported block with water jacket mod

Eccentric shaft oil jet mod

SS braided oil lines w/ new injectors

5-20 oil on break in and switched to 10-30 on last change. oil pressure peaks at 110, idles is at 30 and highway cruise is 60.

Take off the ehxuast manifold and have a peak inside.

GoRacer,Dec 14 2004, 12:30 PM



I ran stock boost, front rotor blew with less then 3k on new engine. They blamed it on the PFC with stock map and street port, but the plugs were not white, they were dark brown on one and oil black on the other. The only other factor was the ACV had disconnected. They gave me the possiblity of side seals failing but without opening it up, I won't know and may never prove since i'm still driving it. I need to do two races for the Mazdacomp membership before I tear it down so I can can some discounts. My finish place or time does not matter as long as I complete. There was no bang, no noise other then a woosh, woosh, woosh, like the seals just fell out. This was the 2nd time I opened her up. The 1st at 6krpm but this time I hit 8k with a possible peak of 8.2krpms. Boost was at 10lbs and on the 6k run it never creeped nor spiked but without a recordable gauge or datalogic, I have no proof of anything. I don't want to blame someone for something I did but at the same time I don't want to be blamed for something I didn't do either! Oh, eccentric shaft/front cover bolt was never torqued down. I did tighten it when I found out but my torque wrench is inch lbs and not foot lbs (D'oh). https://www.nopistons.com/forums/pub...O_DIR#>/11.gif



stock twins

Apexi FMIC & intakes

Apexi PFC w/stock map

HKS DP

Border Racing Burnout Exaust & Hi-Flow Cat'

Stock injectors (cleaned before install)

Stock fue pump

boost = 10lbs (PFC controled)

Street Ported block with water jacket mod

Eccentric shaft oil jet mod

SS braided oil lines w/ new injectors

5-20 oil on break in and switched to 10-30 on last change. oil pressure peaks at 110, idles is at 30 and highway cruise is 60.







A side seal failure will generally show up as compression lost on one rotor face.



Apex seal and corner seals show up as lost compression on two faces. How this helps you I don't know. Measure the compression, and if there has been a failure, pull the engine and fix it. Why put it off. Out, fixed and back in, in one day should be possible.



Lynn E. Hanover

Air tools are nice to use when you're under the clock.

Why put it off? Money! another $2k-$4k ...assuming it was my fault.



Compression check was:

Front = 0-0-0

Rear = 7-7-7



Compression lost to all three faces, which you don't have listed. Can all three side seals fall out if improperly installed? Can you blow side seals?



Spark plugs do not show lean condition but would it show for only run?



I'm getting two different answers on PFC

1. Timing is advanced on stock map

2. Stock map is fine for 10lbs even with street port.

stock timing is fine on pfc, its more advanced then most people run, after 10 psi i woudl retard a bit just for safety.

with the motor ported you most likely have to add some fuel. if that wasnt done i am sure thats why you blew up. the stock pfc fuel map is good for mostly stack car and some boltons after that you start to lean out.



0 on all 3 faces pretty much means all teh apex seals in that rotor are busted, apex seals are mostly what blows up, side seals dont alwasy go.

take the exhaust manifold off look inside the port at the apex seals see if there broken if not than the springs are flat either way youll have to take the engine apart. https://www.nopistons.com/forums/pub...IR#>/wacko.png

Man, that sounds like an overheated engine???



Who did the rebuild?





-Tedh

o-o-o compression sounds ugly. Apex seals should be broken..

You don't have to have race results to get a membership with Mazdacomp. If your car isn't running, you can send them a picture of your car, with a copy of your SCCA membership car. You just have to tell them when you think the car will be runnning again, and then go race and send them results.