Why does your motor blow?

[ptperformance]

Originally Posted by Lex ^ See post 553 John. Part throttle blow-up is a misconception that you keep on perpetuating. Plenty of cars blow WOT. The bending/damage is done at high cylinder pressures. Once it's bent, the rod lets go at any time.

OK, say its not part throttle. Why is it then that guys can abuse their motors for endless miles under WOT, un-tuned, lots of knock and never blow? Several have had knock, several have pushed very hard on this motor with very big turbos and never blow? Why?

[ms3077]

The title of this thread basically implies everyone's engine is destined to blow. It sounds like a scare tactic. I suppose it’s a good way to get attention but damn it’s a bit misleading to say the least.

[06Speed6]

I feel the need to repost one of my posts here...

Originally Posted by 06Speed6 315ftlb @ 2000rpm is not at all the same stress on the rods as 315ftlb @ 5000rpm. Its all about where on the stroke the peek cyl pressure is achieved. At low rpm our peak cyl pressure comes in very close to tdc so there is very little leverage on the crank and the cyl pressure required to hit 315ftlb is very high. As the rpm goes up, peak cyl pressure is reached further past tdc when the piston has more leverage due to the increased rod angle and as a result less cyl pressure is required to hit 315ftlb. However, on paper, if peak cyl pressure is achieved at the same point on the stroke, then the cyl pressure required to hit 315ftlb is the same regardless of rpm since torque is basically just a calculation of cylinder pressure and rod angle.

That is the reason I believe we are blowing at low rpm and not at high rpm. After further research, I am also starting to believe that we need to lock the ign timing down to a certain curve so that it isnt bouncing around all over the place. Predictability is key to building a high hp engine.

[ptperformance]

Originally Posted by ms3077 The title of this thread basically implies everyone's engine is destined to blow. It sounds like a scare tactic. I suppose it’s a good way to get attention but damn it’s a bit misleading to say the least.

Why does your motor blow?

That sounds like a scare tactic to you? Sorry, but that was not the intent of this thread. How about that other thread, "The real reason your motor blows", what does that sound like to you?

There was no intention to "get attention" I have enough negitive to last a lifetime on this forums by other members that have never even owned or installed one of our parts, LOL.

I have seen several blown motors from the MS3/6 but the number of SRT4 motors that have blown compaired to the DISI motor is flat scary.

[ptperformance]

Originally Posted by 06Speed6 I feel the need to repost one of my posts here... 315ftlb @ 2000rpm is not at all the same stress on the rods as 315ftlb @ 5000rpm. Its all about where on the stroke the peek cyl pressure is achieved. At low rpm our peak cyl pressure comes in very close to tdc so there is very little leverage on the crank and the cyl pressure required to hit 315ftlb is very high. As the rpm goes up, peak cyl pressure is reached further past tdc when the piston has more leverage due to the increased rod angle and as a result less cyl pressure is required to hit 315ftlb. However, on paper, if peak cyl pressure is achieved at the same point on the stroke, then the cyl pressure required to hit 315ftlb is the same regardless of rpm since torque is basically just a calculation of cylinder pressure and rod angle. That is the reason I believe we are blowing at low rpm and not at high rpm. After further research, I am also starting to believe that we need to lock the ign timing down to a certain curve so that it isnt bouncing around all over the place. Predictability is key to building a high hp engine.

I think we need to take the time and check rod ratio's of these motors. This would give us a better starting point to determine if the SRT4 motor has more cyl pressure "leverage" on the crank than the DISI motor.

I agree with you on the timing and low RPM TQ numbers but I still feel that there is a single event that causes the motor to blow. If it were only low RPM WOT applications that caused the motor to blow... you would be able to duplicate the condition on all cars. I use to try and get my motor to blow (2nd motor) and no matter what I did, even 5th gear pulls at 25 MPH would not cause a motor failure or knock. I think that there might be something worth looking into with the timing, but yet again it should be repeatable on "all" cars, not just the handful that we see blowing up.

The oil in the intake after a motor bends rods has be concerened. Either the oil was there before the rods bent, or it was there after. I can figure out how the oil got there before, but after doesn't make any logic. The only way to get oil into the intake after a rod bending event would be to have the PCV system fail at that exact moment of the failure. Ring seal will not put oil deposits into the intake manifold, that is imposssible.

[FORZDA 1]

Originally Posted by ptperformance ...... Ring seal will not put oil deposits into the intake manifold, that is imposssible.

Well, not directly of course, however, when the rings loose seal under boost, the crankcase pressure skyrockets and will likely fill and pressurize the PCV oil separator and cam cover breather until the driver lets off the throttle and the PCV opens under the part-throttle vacuum. Then the pressurized oil in the PCV tank is blasted into the intake manifold....

[mrFanel]

So has anyone had a chance to compare a 1st gen to a 2nd gen? I am quite curious at this point... not too much of a big deal for me since the car is under wty, has 4K miles on it and the dealer I bought it from is pretty chill but still... this is a bit disconcerting and I would hope someone at Mazda would man up....



Question though... is the fundamental block design of the 2.3 DISI block the same as the regular 2.3 NA motor (without, I suppose, the strengthened components, but you get the idea)? Wouldn't... those blow as well? (Sorry if its a rhetoric question that has been answered as well )

[06Speed6]

If a intake valve is damaged and there is no piston in the bore...

Originally Posted by mrFanel Question though... is the fundamental block design of the 2.3 DISI block the same as the regular 2.3 NA motor (without, I suppose, the strengthened components, but you get the idea)? Wouldn't... those blow as well? (Sorry if its a rhetoric question that has been answered as well )

No its almost completely different.

[Lex]

^ PCV box on the side of the block is very similar however.

[FORZDA 1]

Originally Posted by 06Speed6 If a intake valve is damaged and there is no piston in the bore...

Yup, that too

[ptperformance]

Originally Posted by FORZDA 1 Well, not directly of course, however, when the rings loose seal under boost, the crankcase pressure skyrockets and will likely fill and pressurize the PCV oil separator and cam cover breather until the driver lets off the throttle and the PCV opens under the part-throttle vacuum. Then the pressurized oil in the PCV tank is blasted into the intake manifold....

That is the best condition that I could see happening. But what about those that don't loose ring seal? I just got pictures of a car that didn't loose ring seal and guess what... ton's of oil inside the intake manifold. This is what confuses me when it comes to the oil in the intake on the DIZI motor.

Originally Posted by mrFanel So has anyone had a chance to compare a 1st gen to a 2nd gen? I am quite curious at this point... not too much of a big deal for me since the car is under wty, has 4K miles on it and the dealer I bought it from is pretty chill but still... this is a bit disconcerting and I would hope someone at Mazda would man up.... Question though... is the fundamental block design of the 2.3 DISI block the same as the regular 2.3 NA motor (without, I suppose, the strengthened components, but you get the idea)? Wouldn't... those blow as well? (Sorry if its a rhetoric question that has been answered as well )

They are different but very slight and you have to be sharp to catch the changes. I am not going to share what they are, until I have had the oppritunity to tear down a few more 2010's. One thing I can say without question... it appears that the bore diameter has changed. Confirmed this on two 2010 motors so far.

Originally Posted by 06Speed6 If a intake valve is damaged and there is no piston in the bore... No its almost completely different.

Other than the obvious reasons, LOL.

Originally Posted by Lex ^ PCV box on the side of the block is very similar however.

This goes back to my reasons for blown motors, PCV system is of a very poor design and under boost the box fills up and causes a sealed system. Then when you slam the throttle shut, open it up again under boost it creates the snap vacuum. If the box is 1/2 of the way full of oil when this happens it only complicates the problem of an already poorly designed system. But that is my therory and until I can prove it... its just therory.

[Joern]

hi PTP
how much longer will it be untill u are ready to sell your kit?

[ptperformance]

Originally Posted by Joern hi PTP how much longer will it be untill u are ready to sell your kit?

Months, we need to make sure that its working 100% on several cars before we release it to the market. I don't need to take any heat from the haters because "one car" didn't respond well to the fix.

[Joern]

Originally Posted by ptperformance Months, we need to make sure that its working 100% on several cars before we release it to the market. I don't need to take any heat from the haters because "one car" didn't respond well to the fix.

can i join the testing? u will get the chance to test it on an european car..

[ptperformance]

Originally Posted by Joern can i join the testing? u will get the chance to test it on an european car..

Contact me via email or PM and we can discuss some options.

[blacksin]

I've got a 2007 MS6 with 35,000 miles. My only mods are the AP with Stage 1 + SF 91, and the COBB SRI. My MAF has been calibrated (oddly enough, my AP shows +5 LTFT at idle with AC on, but it's being recorded as 8.42 in the spreadsheet. When my AC is off, the LTFT @ idle goes back down to +1 - +2).

I had my cruise control set @ 70 m.p.h. for about 25 miles in this record MD humidity. Pulling off the highway to a low throttle, vacuum state, I noticed the knock on my AP wiggin' out. I recorded the following:




Now I've lurked all around the forums, and I've seen so many theories. I've read all 15 pages of this oil theory. Some people tell me that this is "normal" because it's the car adjusting timing. Others say that the golden ticket is just adjusting the load for low throttle in ATR. Others say that this is phantom knock since the knock is going down to zero, and I should just "ride it out." This knock only happens when the car is warmed up and from a very slow start in vacuum. Like most other people, I don't have any knock during high throttle situations. To me, this isn't normal, and I want to find a way to make it stop. I've seen everything from "it's completely normal" to "you're car is going to die! AHHH!"

I guess I don't have much to add to this thread, other than just saying I hope this isn't the oil issue... but then again, some people say that the MS6 doesn't have the oil pop issue as much as the MS3... It just doesn't make sense to see that much knock when the acelerator position is only on 10-20%.... so confused....

[ptperformance]

Originally Posted by blacksin I've got a 2007 MS6 with 35,000 miles. My only mods are the AP with Stage 1 + SF 91, and the COBB SRI. My MAF has been calibrated (oddly enough, my AP shows +5 LTFT at idle with AC on, but it's being recorded as 8.42 in the spreadsheet. When my AC is off, the LTFT @ idle goes back down to +1 - +2). I had my cruise control set @ 70 m.p.h. for about 25 miles in this record MD humidity. Pulling off the highway to a low throttle, vacuum state, I noticed the knock on my AP wiggin' out. I recorded the following: Now I've lurked all around the forums, and I've seen so many theories. I've read all 15 pages of this oil theory. Some people tell me that this is "normal" because it's the car adjusting timing. Others say that the golden ticket is just adjusting the load for low throttle in ATR. Others say that this is phantom knock since the knock is going down to zero, and I should just "ride it out." This knock only happens when the car is warmed up and from a very slow start in vacuum. Like most other people, I don't have any knock during high throttle situations. To me, this isn't normal, and I want to find a way to make it stop. I've seen everything from "it's completely normal" to "you're car is going to die! AHHH!" I guess I don't have much to add to this thread, other than just saying I hope this isn't the oil issue... but then again, some people say that the MS6 doesn't have the oil pop issue as much as the MS3... It just doesn't make sense to see that much knock when the acelerator position is only on 10-20%.... so confused....

Does your clutch pedal vibrate when you push it in? Something is wrong with your car or sensor considering you have knock all the time, which is bad!

[blacksin]

Originally Posted by ptperformance Does your clutch pedal vibrate when you push it in? Something is wrong with your car or sensor considering you have knock all the time, which is bad!

Nope, my clutch pedal doesn't vibrate, and i'm not knocking all the time as the spreadsheet attached to my previous post shows, just @ that rpm in the pic, under vacuum, after cruising on the highway. I think I had a tank of bad gas 'cause i'm getting much less knock now. But I still have a few degrees right at that point of the rpm band with very light throttle. But again, no knock whatsover under medium to wot above 3000 RPMs... Plus, it's silent, no rattling or pinging whatsoever. I feel like if it was knocking that much, you would hear/feel/see something.

[ReD BoY]

first of all, I didnt read through the middle 9 pages of comments to this thread... I read the first thinking there was only one and when I realised there were 12 pages I just skipped to the last one.

So my question may have already been mentioned, but this is what's on my mind... I know that people have talked of relieving the car of backpressure by eliminating cats enables the oil to leak past the turbo and cause the exhaust to smoke.

some argue that if you have a leak after you had a leak before and the cats were just hiding it.

you mentioned oil everywhere, could relieving backpressure increase this risk..? significantly?

by the sounds of it you're developing a fix, the supposed fix to having the catless pipes was a pill, an oil catch can, or switching to 40 wieght oil. Im not too technical and I dont really know why switching oild would help leaking but do any of these seem to be headed on the right track? Or is what you're doing now supposed to be the "all powerful" fix?

I think Im getting a full CorkSport turboback exhaust next week and I just want to know what Im risking.


thanks

[wcm250f]

hey ptp. just curious was there a specific reason why you got to tear down a couple 2010 ms3? or did something happen to the motor?

[ptperformance]

Originally Posted by ReD BoY first of all, I didnt read through the middle 9 pages of comments to this thread... I read the first thinking there was only one and when I realised there were 12 pages I just skipped to the last one. So my question may have already been mentioned, but this is what's on my mind... I know that people have talked of relieving the car of backpressure by eliminating cats enables the oil to leak past the turbo and cause the exhaust to smoke. some argue that if you have a leak after you had a leak before and the cats were just hiding it. you mentioned oil everywhere, could relieving backpressure increase this risk..? significantly? by the sounds of it you're developing a fix, the supposed fix to having the catless pipes was a pill, an oil catch can, or switching to 40 wieght oil. Im not too technical and I dont really know why switching oild would help leaking but do any of these seem to be headed on the right track? Or is what you're doing now supposed to be the "all powerful" fix? I think Im getting a full CorkSport turboback exhaust next week and I just want to know what Im risking. thanks

I am going to say yes that the reduction in back pressure causes the oil pressure to overcome the seal in the turbine side of the turbo, or we just have a horrible oil return system that backs up with oil because of the PCV system.

The pill that we made has solved 99% of all oil burning issues.

Originally Posted by wcm250f hey ptp. just curious was there a specific reason why you got to tear down a couple 2010 ms3? or did something happen to the motor?

I ordered new parts from the dealer to see the differences when we started a forged motor build for a customer. The very first thing that I caught was the drivers side nipple off the valve cover was smaller inside and a few other changes that made me go hmmm.

When I pulled the motor down I wanted to be sure that I was seeing the proper things so I decided to order a few items up to verify. Pistons are different and rods weigh more then the older version.

[wcm250f]

alright thanks. just wanted to see if you had any bad info about the 2010 ms3

[ptperformance]

Originally Posted by wcm250f alright thanks. just wanted to see if you had any bad info about the 2010 ms3

Nothing yet.

[turbospeed]

the pcv hole is smaller thats all ive heard about the 2010

[pzr2874]

Why in the hell would mazda make a smaller diameter on the PCV for 2010 ?? If that's the case, what does Mazda know ?

[PAM.srt4]

you don't need a fix for the 2010, the oil burning problem was fixed by Mazda with the new year!!!!!!

[pzr2874]

Ok, so WTF were the fixes? Other than the oil burning issues?

If you're saying "a fix" was done.... And the oil issue was done... then we can ALL just order the new PCV system ?

[GoSpeed3Go]

hopefully poeple can see that the 2010 speeds arent blowing cause they dont have many playing at home dyno tuner with the software yet thanks to a lack of support for the moment which is probably a good thing.

[treyclash]

with this problem being able to be proven i vote someone making an example of mazda and taking them to court for a recall like they did a few months back to hyundai for the tiburon clutches

[pzr2874]

Originally Posted by triplejumper18 Fixed

Funny shit...

BUT.... what I get out of what you are saying is that tuners are responsible for this(these) engines having problems. I disagree....

1-these engines had issues prior to many of the tuners

2-COBB and likes DO their R&D, they have WAY too much to lose from half-assing their products.

3-We wait and see what the GenPu have to show and go from there.

4-You would think FORD and Mazda would man-up and show some love for MS buyers.