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Discussion Starter #1 (Edited)
decided to check my plugs today anyway I did a compression test while I was at it, just wanted a baseline of what the cylinder pressure was. ( I know that cams have alot to do with changing it )


Now the results were interesting.. anyone care to chime in

Cylinder 1 : 130
Cylinder 2 : 130
Cylinder 3 : 126-9 ( needle was inbetween 125 and 130 )
cylinder 4 : 130

now those numbers are low ??? I was really suprised.. btw I tested each cylinder 3 times

my old 89 Conquest tsi with SEVEN to one comp ratio made 140 on a cold block..


this doesn't seem right, I was expecting at least 150+ even if the cams were making it lower.


on a side note, I called up tripoint today, asked a bunch of turbo related stuff and the 2.5, seems the 2.5 is capable of handling 300whp on bone stock block. Another thing I was told other then having a CEL light on, our cars CAN use piggybacks. Mark @ tripoint told me the cel light is the only thing that will happen, no timing curve changes etc.. on an AEM FIC.which is great news. Another thing is they offer base map tunes for turbo 2.5s on AEM FIC with 44lb injectors and the harness for =850$.. nice!
 

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College Zoom-Zoom
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decided to check my plugs today anyway I did a compression test while I was at it, just wanted a baseline of what the cylinder pressure was. ( I know that cams have alot to do with changing it )


Now the results were interesting.. anyone care to chime in

Cylinder 1 : 130
Cylinder 2 : 130
Cylinder 3 : 126-9 ( needle was inbetween 125 and 130 )
cylinder 4 : 130

now those numbers are low ??? I was really suprised.. btw I tested each cylinder 3 times

my old 89 Conquest tsi with SEVEN to one comp ratio made 140 on a cold block..


this doesn't seem right, I was expecting at least 150+ even if the cams were making it lower.


on a side note, I called up tripoint today, asked a bunch of turbo related stuff and the 2.5, seems the 2.5 is capable of handling 300whp on bone stock block. Another thing I was told other then having a CEL light on, our cars CAN use piggybacks. Mark @ tripoint told me the cel light is the only thing that will happen, no timing curve changes etc.. on an AEM FIC.which is great news. Another thing is they offer base map tunes for turbo 2.5s on AEM FIC with 44lb injectors and the harness for =850$.. nice!
They do know their stuff...
 

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Discussion Starter #5 (Edited)
I don't think he lied, but there is a reason why people don't do piggybacks for the Mazda 3. Most people hear piggyback they think of the Apexi Neo, I'm not a pro but the AEM FIC is a bit more complex.
obviously, but it is still a piggyback like greddy e manage ultimate. and other " almost standalones"

so i'm guessing nobody thinks my cylinder pressures are out of whack.:rulez2 1::sad 1::argh 1:
 

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obviously, but it is still a piggyback like greddy e manage ultimate. and other " almost standalones"
Should ask all the people on the first gen forums that shoot down people asking about piggybacks why they don't recommend their use.
 

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Smells of Elderberries
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In the factory manual under the technical data section it lists the compression for the 2.5L as 1324kPa (192psi) max and 927kPa (134psi) min with no more than a 196.1 kPa (28.5psi) variance between cylinders.

Personally I'd buy a new gauge and check it again or try the small bit of oil in the cylinder bore and check again and hopefully the compression doesn't go up :sad 1:
 

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On that college budget
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Dynotron I don't think said it would never work it is just they are a PITA to tune and harder to use aka not recommended for tuning a car lol. But, if everything works out it would be great to hear. Give people even more reason to go turbo/supercharger or whatever.
 

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Discussion Starter #9
im gonna try the oil in the cylinders, i'm thinking my elevation + 90 degrees outside played a factor into it?
 

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Smells of Elderberries
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You are correct that altitude is playing a part in the reading also the quality of the gauge affect the reading. I wouldn't be to concerned unless one cylinder was reading dramatically less than the other 3. Here is a chart I found for the altitude correction.

The following chart provides conversion factors for correctly compensating for changes in altitude:

Compression Test Altitude Compensation Factors
Altitude Factor
500 0.987
1500 0.960
2500 0.933
3500 0.907
4500 0.880
5500 0.853
6500 0.826
7500 0.800
8500 0.773
 

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Dynotron I don't think said it would never work it is just they are a PITA to tune and harder to use aka not recommended for tuning a car lol. But, if everything works out it would be great to hear. Give people even more reason to go turbo/supercharger or whatever.
Bingo

BTW, I know the guys at Tri-Point very well, and while Mark (or Craig) would never lie to you, he also did not tell you that the piggy back solution is not what they prefer, which is why they called us when they started working on the 2.5 turbo kit.

An you keep mis quoting me, as I have told you time and again that yes you can make the better piggy backs work on fueling, however the factory ecu is NEVER going to allow the piggy back to simply dump more fuel. Again, you can do the exact same thing with a rising rate regulator.

The big problem with the piggybacks is the simple fact that they cannot correctly adjust the sync and ref signals for the timing, its that simple. The Mazda MZR uses a very complex set up to keep the ecu aware of the engine timing, and without being able to modify this signal and duplicate it as an offset, you cannot adjust timing, and timing advance is the one thing you need to adjust instantly at boost onset.

I suggested the regulator because you keep trying to cheap this project, and its far less expensive. You seem determined to reinvent the wheel here, so please, don't let a bit of free advice stop you. I think I have been more than supportive of your project, and have tried to offer constructive input to help you on your way. But that said, it seems you take offence if someone trys to give you advice you don't want to hear.

If you feel that you understand the control system on the Mazda3 well enough to play russian roulette, then by all means, press on regardless
 

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General
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Tri-point came out with a couple of kits priced at $4500, are there any left?
 

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General
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NVM, looks like they still got them.
 

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Discussion Starter #14
Bingo

BTW, I know the guys at Tri-Point very well, and while Mark (or Craig) would never lie to you, he also did not tell you that the piggy back solution is not what they prefer, which is why they called us when they started working on the 2.5 turbo kit.

An you keep mis quoting me, as I have told you time and again that yes you can make the better piggy backs work on fueling, however the factory ecu is NEVER going to allow the piggy back to simply dump more fuel. Again, you can do the exact same thing with a rising rate regulator.

The big problem with the piggybacks is the simple fact that they cannot correctly adjust the sync and ref signals for the timing, its that simple. The Mazda MZR uses a very complex set up to keep the ecu aware of the engine timing, and without being able to modify this signal and duplicate it as an offset, you cannot adjust timing, and timing advance is the one thing you need to adjust instantly at boost onset.

I suggested the regulator because you keep trying to cheap this project, and its far less expensive. You seem determined to reinvent the wheel here, so please, don't let a bit of free advice stop you. I think I have been more than supportive of your project, and have tried to offer constructive input to help you on your way. But that said, it seems you take offence if someone trys to give you advice you don't want to hear.

If you feel that you understand the control system on the Mazda3 well enough to play russian roulette, then by all means, press on regardless
I asked mark about this aswell, for timing, He said they have a hexadecimal file that will work with the FIC to be able to recognize mazdas timing signals.

i'm not trying to cheap on this project, and I don't think the rising rate regulator will do anymore good then bad. if your shop was closer to me, i'd be happy to take my car in and pay for a tune. if these mazdas were not drive by wire, then it would have been problem solved ages ago with megasquirt/ems. I don't really understand how the ecu will never allow a piggyback to dump fuel, when the piggyback is intercepting the pulse to the fuel, for what is set priorly in the piggyback, regardless of what the ecu wants, that's the entire point to it.

that's saying a fuel controller wont add more fuel when X amount of Y is reached ( air,boost,kpa etc ) because the ecu doesn't want it too? what's going to happen , the ecu will no into negative trim to what -25% , then throw a cel and leave it at -25%, and the piggyback would say " ok i give up? ) it's not like the ecu is going to completely drop from pulsing the injectors even at max - trim. I'm not trying to say i'm right your wrong, or your right i'm wrong, or argue, I just really don't understand how this ecu is SOO special that it can overcome everything.

i'm about to drive my car off the side of a mountain because of these stupid ass MAF's..worst thing mazda ever though to do was use this shit ass maf.
 

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I asked mark about this aswell, for timing, He said they have a hexadecimal file that will work with the FIC to be able to recognize mazdas timing signals.

i'm not trying to cheap on this project, and I don't think the rising rate regulator will do anymore good then bad. if your shop was closer to me, i'd be happy to take my car in and pay for a tune. if these mazdas were not drive by wire, then it would have been problem solved ages ago with megasquirt/ems. I don't really understand how the ecu will never allow a piggyback to dump fuel, when the piggyback is intercepting the pulse to the fuel, for what is set priorly in the piggyback, regardless of what the ecu wants, that's the entire point to it.

that's saying a fuel controller wont add more fuel when X amount of Y is reached ( air,boost,kpa etc ) because the ecu doesn't want it too? what's going to happen , the ecu will no into negative trim to what -25% , then throw a cel and leave it at -25%, and the piggyback would say " ok i give up? ) it's not like the ecu is going to completely drop from pulsing the injectors even at max - trim. I'm not trying to say i'm right your wrong, or your right i'm wrong, or argue, I just really don't understand how this ecu is SOO special that it can overcome everything.

i'm about to drive my car off the side of a mountain because of these stupid ass MAF's..worst thing mazda ever though to do was use this shit ass maf.
in short, and I think we have done this a time or two, the ecu is NEVER IN AN OPEN LOOP SITUATION on the later model cars. So when you add fuel thru the piggy back, the ecu removes fuel because the lambda gos ape shit( remember you just added fuel), so once this happens, you come back and add more fuel to your piggyback, and the same thing happens. Now on your car this gos on for two or three cycles untill the stft and ltft are bottomed out, then very interesting things start to happen with timing, egr cycle and cam duty cycle because the poor ecu thinks it has a fueling issue, and is trying to get back to commanded lambda. And this is just the begining of the cycle, it gets so bad that the car is not even driveable.

If you do a bit of digging on the other platforms that have this engine. You will find that lots of information is out there about why the piggybacks don't play well with the FI set ups. Thousands and thousands were spent on the MX5 to fit and tune a piggyback when Cosworth put out the SC kit for them. Xede, has a first class unit that is way more advanced than anything on the market so far, and there are a ton of them on shelves now because they were ripped off in frustration

Like I said before, there are ways to make it work, but the cars really don't run anywhere near as well as they could, and drive like shit due to the conflicts of operation.

All I am telling you is you need to understand what it is your working with before you make a modification. You have been f^&king lucky so far with what you are doing. Case in point is your MAF issue. there is nothing wrong with the MAF sensor itself, but you don't understand how or why it works, and its relation to the rest of the system. Study the system, understand why it does what it does. And why the engineers placed it where it was, and what the air flow looks like both before and after your modifications. Look to see what it is you have done that could cause the issue your having.
 

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Jackf where did u get your DPtune ECU flash? And Orange what turbo is reccomend for the 2.5?
I'm not JackF, but it is the dynotronics tune, check out the group buy thread. I am sure you could fill one of the spots. A few of us, me included, are having it done sooner than later.
 

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Discussion Starter #20
If you understood how it worked you would see what you have done to make it"touchy"
Well being honest i have only ever worked with mitsu honeycomb larger mafs. Which arent as touchy. I fixed my maf placement and seems to be better. Afrs are still out of whack but i believe i found the culprit. The gas vapor purge ( i believe that is what is it) ( large vac line to solenoid to hardline on firewall ) well i think it was leaking or stuck open because i disconnected that, closed the line and my idle afr is 14.7 on the spot. Sometimes goes to 15.3 but then back to 14.7 i think i will still run lean until i fill up again cuz i have like 4 gallons of E85 in the tank.

I have the maf about 2 or 3 inches from the throttle in the same diagnal direction as the throttle, with a same size pipe on the other side of the maf then it goes to 2.5

As for the person who asked about what turbo. Well the speed 3 manifold and speed turbo bolt right up, but spool up is retarded quick. Like fully spooled by 2200rpm
 
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