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Zoom Zoom BOOM - I joined the blown up club.
- Thread starter flyrevs
- Start date
Yes, many. Another forum has a list and it's pretty high - over 30 I think. Any body know the number ? Plus the number is much higher because a lot of people are not on the forum so they are not included in the total.nice.. are these things really blowing up alot??
wow great write up russum, thanks for taking the time out to even write all that.. well this suks man, and here i thought making alot of tourque quick was a good thing... so it pretty much comes down to tuning these things so that the boost doesnt spike so fast therefore not making so much tourque early in the rpms.. man thanks alot for that write up, if more people read this and take the advice, i think that blown motor number might start 2 slow down a bit..
This is great info, BUT who would tune our engines? Mazda? If we did it on our own and then still zoom zoom boom, I see voided warranty right there. I'd be crying...can't afford to buy new /rebuild engine. Hopefully Mazda will come out with a solution. They must be concerned since they are losing money with every engine that blows.
Excellent analysis, Russm. I've followed this "small end rod taper" issue on another forum and am glad to see the discussion coming here.
There are many reasons to believe that this taper does produce much higher levels of torque induced stress at low rpm, where torque is applied at its greatest strength when coming on boost and where exposure to the force is longest due to the low rpm.
Your suggestion that some low end torque should be tuned out of the car at low rpm makes sense. I'm thinking that one way Mazda could do that in the future (besides ECU remapping) would be by modified camshaft lobe profile and in remapping the variable valve timing, which could keep torque down at low rpm, even if boost were raised.
I think this issue may be why boost creep or raising boost levels above stock levels may be poison to these engines at light throttle and low rpm settings.
Just thinking out loud without giving it a lot of analysis.
I wonder if the short term lesson band aid in this for us is to remember to keep rpm up a bit by staying in a lower gear than we might otherwise when we are coming up on boost. That way we are at least keeping the engine closer to 3500 rpm rather than 2800 when we roll onto boost where boost pressure and torque are both at their highest. It's not a fix, but it might be good to think this way when we drive.
In short don't lug the damn engine and don't drive around at the typical 2500-2700 just off boost rpm and roll into boost. Downshift first, then bring in the boost.
A couple of thoughts:
1) A lot of the "inherent tuning" of this engine is a product of the turbo itself (a small turbo that can spool up quickly but becomes inefficient at higher RPM's).
2) One possible contributing cause to blown engines is a boost spike which often occurs at low to mid RPM throttle transitions. If detonation doesn't occur, the boost spike results in a "torque spike". If detonation does occur, that is also bad.
A couple of thoughts:
1) A lot of the "inherent tuning" of this engine is a product of the turbo itself (a small turbo that can spool up quickly but becomes inefficient at higher RPM's).
2) One possible contributing cause to blown engines is a boost spike which often occurs at low to mid RPM throttle transitions. If detonation doesn't occur, the boost spike results in a "torque spike". If detonation does occur, that is also bad.
Im not sure about #2.
This is great info, BUT who would tune our engines? Mazda? If we did it on our own and then still zoom zoom boom, I see voided warranty right there. I'd be crying...can't afford to buy new /rebuild engine. Hopefully Mazda will come out with a solution. They must be concerned since they are losing money with every engine that blows.
i don't think their losing that much money...
they are using every excuse in the book to deny warranty for blown motors and hoping people forget about warranty service or force them to take legal action ...
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A couple of thoughts:
1) A lot of the "inherent tuning" of this engine is a product of the turbo itself (a small turbo that can spool up quickly but becomes inefficient at higher RPM's).
2) One possible contributing cause to blown engines is a boost spike which often occurs at low to mid RPM throttle transitions. If detonation doesn't occur, the boost spike results in a "torque spike". If detonation does occur, that is also bad.
I think tons of low end torque is what blows these motors. Torque shouldn't be peaking so low in the power band. And then equate a boost spike in at 3500 rpm's without detonation. I've seen as high as 413 ft-lb's of torque created by a spike, in fact, that dyno is in this forum.
Darth Vader
Member
Having a good quality bypass valve (Forge) has tamed the spikes on my engine. It pretty much runs to 16 and stops dead there, which is fine with me, I'm trying to see what I can do without adding more boost to the already close to surge K04.
That said, boost spikes don't kill motors, unless they are sustained, which makes it not a spike anymore. The low end grunt does put a HUGE amount of strain on the rotating ass'y. This isn't a diesel. At light throttles, not such a big deal but, load it a bit with less than 3K on the tach and the strain is gigantic, way higher than WOT. I try not to do this if I can help it and, it doesn't take Boom threads to know that's good practise with any engine.
That said, boost spikes don't kill motors, unless they are sustained, which makes it not a spike anymore. The low end grunt does put a HUGE amount of strain on the rotating ass'y. This isn't a diesel. At light throttles, not such a big deal but, load it a bit with less than 3K on the tach and the strain is gigantic, way higher than WOT. I try not to do this if I can help it and, it doesn't take Boom threads to know that's good practise with any engine.
I tried to drive the car in the manner I posted on this tread -- trying not to roll onto the boost in a higher gear with low revs, trying to avoid that transition from 2500 to 3000 where you come up on boost -- trying to downshift first to bring the revs up a bit. It can be done, but it is very unnatural, counter intuitive, and I don't think most people will want to drive that way.
I found myself this morning running on the Interstate at 2800 rpm in 6th gear just barely into boost and wanting to just ease into the throttle to pull around another car. I did it without thinking about how the sudden boost rise at that rpm was torque hammering the s*** out of my connecting rods.
If the rod taper design is the problem, it plays right into the normal driving habits of even unmodded drivers and explains the zoom, zoom pop.
With my mods, I'm already out of warranty anyway. I'm leaning toward an AP tune now with an idea of trying to find a custom tune that would hold boost back a bit at lower rpm, while still providing the benefits of a good tune from 4k rpm on up.
Travis @ Cobb? Where are you? Maybe you guys could work on developing some mapping that would focus on this issue. We really don't need and won't miss 400 pounds of torque at 2000-2500 rpm, do we?
I found myself this morning running on the Interstate at 2800 rpm in 6th gear just barely into boost and wanting to just ease into the throttle to pull around another car. I did it without thinking about how the sudden boost rise at that rpm was torque hammering the s*** out of my connecting rods.
If the rod taper design is the problem, it plays right into the normal driving habits of even unmodded drivers and explains the zoom, zoom pop.
With my mods, I'm already out of warranty anyway. I'm leaning toward an AP tune now with an idea of trying to find a custom tune that would hold boost back a bit at lower rpm, while still providing the benefits of a good tune from 4k rpm on up.
Travis @ Cobb? Where are you? Maybe you guys could work on developing some mapping that would focus on this issue. We really don't need and won't miss 400 pounds of torque at 2000-2500 rpm, do we?
How was your BPV set up when you blew. I had been running blue w/2 but removed one shim when I went AP. I tried the stg2+SF93 & 91 v104 maps but got scared with all the boost and went to stg1+93v104. I will probably reflash with the stg1+sf91 v104 soon for a little more peice of mind.
forge with blue spring / no shims, I would hit 20 and then taper down, worked perfectHow was your BPV set up when you blew. I had been running blue w/2 but removed one shim when I went AP. I tried the stg2+SF93 & 91 v104 maps but got scared with all the boost and went to stg1+93v104. I will probably reflash with the stg1+sf91 v104 soon for a little more peice of mind.
yesterday I joined the club. I was handed some pieces from my 2007 mazada 3 engine block, I am still in shock. I just had my car inspected the week before. Here is what I experienced. Going about 60MPH a ticking sound started on what seem like the passenger side dash board, heat looked good, no indicators were lit. About 5 min after the ticking started, the car thumped, I pulled over to the side of road, then a white puff of smoke come from under the hood on the passenger side, I rolled to a stop. My car is still under warranty, I owned it for 2.5 years and it has only 33K miles on it.
Anybody experience anything like this? Did Mazda honor the warranty? They are requesting all my oil change records. I am not sleeping well these days.
Anybody experience anything like this? Did Mazda honor the warranty? They are requesting all my oil change records. I am not sleeping well these days.
yesterday I joined the club. I was handed some pieces from my 2007 mazada 3 engine block, I am still in shock. I just had my car inspected the week before. Here is what I experienced. Going about 60MPH a ticking sound started on what seem like the passenger side dash board, heat looked good, no indicators were lit. About 5 min after the ticking started, the car thumped, I pulled over to the side of road, then a white puff of smoke come from under the hood on the passenger side, I rolled to a stop. My car is still under warranty, I owned it for 2.5 years and it has only 33K miles on it.
Anybody experience anything like this? Did Mazda honor the warranty? They are requesting all my oil change records. I am not sleeping well these days.
pretty much that what happens when we blow-up ...
a ticking time bomb .... we should gather for class action lawsuit
Super Unique
Member
- :
- 2008.5 Mazdaspeed 3 Black Mica
The engine in our car is common among the speed3, the speed 6, and the cx7, albeit slightly different tunes, Has there been a similar rash of engine failures in the cx-7 crossover suv?
The engine in our car is common among the speed3, the speed 6, and the cx7, albeit slightly different tunes, Has there been a similar rash of engine failures in the cx-7 crossover suv?
No CX7 has a standard transmission. So I am thinking that the give (slippage) in the automatic disperses the torque a little more evenly, rather than our spike.
Ha! That was 3 weeks ago! I drove to Daytona for the Rolex 24 race on Jan 22nd, so now I'm something under 76,000.
I fully expect well over a quarter million miles before I'm done with it in a few years unless fuel prices go back up and force me to buy something slow & thrifty. Bought around Nov 6, 2006 -- I think it was the 2nd or 3rd MS3 in the Richmond VA market.
That was in February, so its probably in the 80,000 or more now.
I tried to drive the car in the manner I posted on this tread -- trying not to roll onto the boost in a higher gear with low revs, trying to avoid that transition from 2500 to 3000 where you come up on boost -- trying to downshift first to bring the revs up a bit. It can be done, but it is very unnatural, counter intuitive, and I don't think most people will want to drive that way.
I found myself this morning running on the Interstate at 2800 rpm in 6th gear just barely into boost and wanting to just ease into the throttle to pull around another car. I did it without thinking about how the sudden boost rise at that rpm was torque hammering the s*** out of my connecting rods.
If the rod taper design is the problem, it plays right into the normal driving habits of even unmodded drivers and explains the zoom, zoom pop.
With my mods, I'm already out of warranty anyway. I'm leaning toward an AP tune now with an idea of trying to find a custom tune that would hold boost back a bit at lower rpm, while still providing the benefits of a good tune from 4k rpm on up.
Travis @ Cobb? Where are you? Maybe you guys could work on developing some mapping that would focus on this issue. We really don't need and won't miss 400 pounds of torque at 2000-2500 rpm, do we?
this post is so full of truth my head almost exploded...
nice work!
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