1974 13b-re Nova
Engine sounds great. Good luck on the new tune. I think things are going to go much better for you now with the new setup.
Is there any reason you didn't go with a unbreakable type seal like RXparts, Goopy, etc? That way just in case this happens again you won't take out another housing/rotor etc.
Is there any reason you didn't go with a unbreakable type seal like RXparts, Goopy, etc? That way just in case this happens again you won't take out another housing/rotor etc.
Joined: Mar 2001
Posts: 31,837
Likes: 3,234
From: https://www2.mazda.com/en/100th/
We never really came to a consensus as to why the first engine blew. Obviously it had to do with the boost spiking up to 27 psi due to denser air on a cool day, but the car was running Sonocco 116 and the afrs were right at 11.0. If everything else was correct, the engine should have been able to handle this. So, I tried to address everything that could have lead to the previous enigne's demise.
- 3 mm Hurley seals vs the previous 2mm Mazda seals. Hopefully they will be a little more detonation resistant
-MSD LS1 coils replace the stock LS1 coils on the leading plugs. The trailing coils are intentionally still the stock LS1's so they are a lower energy. (I'm pulling this out of my ***....so bare with me) Things could have possibly gone awry if the leading plug started to misfire at higher boost, causing the trailing plug to light the mixture later in the cycle. Then the extremely high exhaust temps caused by the late ignition of the mixture could have ignited the intake charge due to the overlap from the bridgeport.
-Plugs have been changed from BUR9EQ's all the way around to 10.5 race plugs on the leading and 11.5 race plugs on the trailing. There is a possibility that the BUR9EQ's were too hot of a plug (especially on the trailing) and lead to preignition.
-Haltech e8 has been replaced with the new PS1000. At the instant the engine blew, the data log dropped out for a second or two and then restarted. Haltech said that this was due to the large amount of electrical noise created by the massive misfiring when the engine blew. It still sits in the back of my mind that maybe the "glitch" that happened the instant the engine blew was the cause instead of the result. Anyway....the PS is supposed to be much more resistant to noise and has much better software that includes "engine protection".
-The overboost protection in the Haltech is now configured and active.....no explanation needed
-Allen thinks that the most likely reason the engine went "boom" was due to extremely conservative timing resulting in high EGTs and ignition of the intake charge. Hence the trip to let the pros tune this time.
-The previous gas I was using was Sonocco 116 supplied by a local performance shop. This is one of those deals where it is transferred from a drum to my container. I can't be a hundred percent sure that the guy pumping didn't get things mixed up and give me the wrong gas. So from now on...........C16 from sealed 5 gallon containers, direct from VP.
- The CAS is being replaced by a Full Function Trigger wheel with a Hall Effect sensor just in case the CAS signal got a little flakey causing the engine to pop. Anything that is more resistant to noise and gives a more stable timing signal is all good in my book. Should have the necessary parts machined to adapt their kit to my gilmer pulley this week.
- EGTs are now being logged in the Haltech. I didn't have this working during the previous dyno runs and might have been able to see that something wasn't quite right prior to the engine letting go. When the engine popped, it was the first run with the EGT's being logged, and by that time, it was too late.
-EGTs in the rear rotor were slightly higher than the front, so now I am running 2% more fuel on the rears vs the front to even them out a bit.
Let's hope the changes pay off. If they don't.....the new tow hooks will!
- 3 mm Hurley seals vs the previous 2mm Mazda seals. Hopefully they will be a little more detonation resistant
-MSD LS1 coils replace the stock LS1 coils on the leading plugs. The trailing coils are intentionally still the stock LS1's so they are a lower energy. (I'm pulling this out of my ***....so bare with me) Things could have possibly gone awry if the leading plug started to misfire at higher boost, causing the trailing plug to light the mixture later in the cycle. Then the extremely high exhaust temps caused by the late ignition of the mixture could have ignited the intake charge due to the overlap from the bridgeport.
-Plugs have been changed from BUR9EQ's all the way around to 10.5 race plugs on the leading and 11.5 race plugs on the trailing. There is a possibility that the BUR9EQ's were too hot of a plug (especially on the trailing) and lead to preignition.
-Haltech e8 has been replaced with the new PS1000. At the instant the engine blew, the data log dropped out for a second or two and then restarted. Haltech said that this was due to the large amount of electrical noise created by the massive misfiring when the engine blew. It still sits in the back of my mind that maybe the "glitch" that happened the instant the engine blew was the cause instead of the result. Anyway....the PS is supposed to be much more resistant to noise and has much better software that includes "engine protection".
-The overboost protection in the Haltech is now configured and active.....no explanation needed
-Allen thinks that the most likely reason the engine went "boom" was due to extremely conservative timing resulting in high EGTs and ignition of the intake charge. Hence the trip to let the pros tune this time.
-The previous gas I was using was Sonocco 116 supplied by a local performance shop. This is one of those deals where it is transferred from a drum to my container. I can't be a hundred percent sure that the guy pumping didn't get things mixed up and give me the wrong gas. So from now on...........C16 from sealed 5 gallon containers, direct from VP.
- The CAS is being replaced by a Full Function Trigger wheel with a Hall Effect sensor just in case the CAS signal got a little flakey causing the engine to pop. Anything that is more resistant to noise and gives a more stable timing signal is all good in my book. Should have the necessary parts machined to adapt their kit to my gilmer pulley this week.
- EGTs are now being logged in the Haltech. I didn't have this working during the previous dyno runs and might have been able to see that something wasn't quite right prior to the engine letting go. When the engine popped, it was the first run with the EGT's being logged, and by that time, it was too late.
-EGTs in the rear rotor were slightly higher than the front, so now I am running 2% more fuel on the rears vs the front to even them out a bit.
Let's hope the changes pay off. If they don't.....the new tow hooks will!
Thread Starter
Joined: Jan 2008
Posts: 438
Likes: 5
From: Ft Worth, Tx
I modified the Full Function Engineering trigger wheel to work with my gilmer setup. Just had to lathe out the center of the pully a bit so the center piece would fit, space out the trigger wheel, and machine a new bracket for the hall effect. Fired right up and runs great!
I modified the Full Function Engineering trigger wheel to work with my gilmer setup. Just had to lathe out the center of the pully a bit so the center piece would fit, space out the trigger wheel, and machine a new bracket for the hall effect. Fired right up and runs great!
Thread Starter
Joined: Jan 2008
Posts: 438
Likes: 5
From: Ft Worth, Tx
Took the car to Steve Kan's new shop in Lewisville, TX today to have him tune the car. Steve was awesome, and the final results are great driveability and 531 whp@21 psi on his mustang dyno. At the end we dialed the boost down to 15 psi for a blast up and down the street. The thing was an ANIMAL! It actually broke the tires loose in 1st gear when the boost hit (with 315 bfg drag radials!).
Vids and dyno charts tomorrow..........
Vids and dyno charts tomorrow..........
Rotary Enthusiast
Joined: Mar 2001
Posts: 1,414
Likes: 0
From: Southern Cali
Took the car to Steve Kan's new shop in Lewisville, TX today to have him tune the car. Steve was awesome, and the final results are great driveability and 531 whp@21 psi on his mustang dyno. At the end we dialed the boost down to 15 psi for a blast up and down the street. The thing was an ANIMAL! It actually broke the tires loose in 1st gear when the boost hit (with 315 bfg drag radials!).
Vids and dyno charts tomorrow..........
Vids and dyno charts tomorrow..........
-Bern
Rotary Enthusiast
Joined: Aug 2006
Posts: 1,216
Likes: 10
From: Melbourne FL/San Antonio TX/Okinawa Japan
Looks like your problem was you turboII CAS. Hate them!
Ive run under 10deg timing over 30psi with no issues.
High EGTs with less timing? Could that just be the fuel is being burned in the manifold causing the high EGTs. But the actual combustion temps are low. ??
Ive run under 10deg timing over 30psi with no issues.
High EGTs with less timing? Could that just be the fuel is being burned in the manifold causing the high EGTs. But the actual combustion temps are low. ??
Thread Starter
Joined: Jan 2008
Posts: 438
Likes: 5
From: Ft Worth, Tx
Dyno chart scan didn't turn out so great, but here it is and a couple of little vids. Need to post the ones of the dyno pulls themselves.
http://www.youtube.com/watch?v=Gu0Tw_udDHQ
http://www.youtube.com/watch?v=VuN-sJPJFOA
http://www.youtube.com/watch?v=Gu0Tw_udDHQ
http://www.youtube.com/watch?v=VuN-sJPJFOA
Thread Starter
Joined: Jan 2008
Posts: 438
Likes: 5
From: Ft Worth, Tx
Couple more vids....
http://www.youtube.com/watch?v=2pdgee0q17E
http://www.youtube.com/watch?v=NMdW-4wrJbs
Thread Starter
Joined: Jan 2008
Posts: 438
Likes: 5
From: Ft Worth, Tx
Thread Starter
Joined: Jan 2008
Posts: 438
Likes: 5
From: Ft Worth, Tx
Finally finished the chassis wiring and took the car for it's first semi-legal outing. Had to drive the car to the painter in Houston to have the bumpers, glove box, front fill panel, and the gas tank I just sumped for Dad's corvette painted. Got lots of thumbs ups and WTF looks. One kid was even following alongside in a WRX and taking a video. The car did great on the cruise, even in the Houston heat.
No barking from the dogs, no smog, and momma cooked a breakfast with no hog....today was a good day.
No barking from the dogs, no smog, and momma cooked a breakfast with no hog....today was a good day.
