whats inside the ms3 motor??

[nig3]

New owner here(spin) uuuhhh so this 2.3 turbo motor...... whats the scooop on the inside components?? does it have vvt, oil squirters, any forged parts, how well does it respond to mods? whats the most whp you have seen on modified ones? are they able to take abuse/do they last?
all i know is that it makes great power from the factory and is a high compresion turbo motor with direct injection and runs a million psi of fuel pressure. please teach me, thanks!!!

[SwampAss]

No one knows how long they will last as that car has been out almost a year.

Here's the sure fire link to all you would ever want to know.


All you ever wanted to know about the MS3 (http://www.mazdas247.com/forum/forumdisplay.php?f=187&nojs=1#goto_forumsearch)

[VermZ06]

New owner here(spin) uuuhhh so this 2.3 turbo motor...... whats the scooop on the inside components?? does it have vvt, oil squirters, any forged parts, how well does it respond to mods? whats the most whp you have seen on modified ones? are they able to take abuse/do they last?
all i know is that it makes great power from the factory and is a high compresion turbo motor with direct injection and runs a million psi of fuel pressure. please teach me, thanks!!!

Well first you should search the forums...there's a lot of info on that very topic.

VVT? No if you're looking for that snag up a honda or mitsu.

The engine does have forged parts. I believe the rods and maybe the crank, but not the pistons.

Oil squirters? No I don't think so...although there is supposedly some sort of system that helps to cool off the turbo after we turn the car off.

I have a CAI on my MS3 and the car responded very well to it and some people claim up to an increase of 20hp with just that single mod...i don't think it's quite that much, but the CAI sounds incredible though and is worth the $$. CBE will give you a little extra hp too, but is probably not as good of a mod as the CAI. A few companies make upgraded TMIC, but I don't see the point unless you're going bigger turbo, although the TMIC install is supposedly and easy one and not very time consuming one. Other then that I would just keep searching.

The only other mod I want is a short throw shifter...i miss the msp nub shifter

good luck

[nig3]

[QUOTE=VermZ06;3450310]Well first you should search the forums...there's a lot of info on that very topic.

"VVT? No if you're looking for that snag up a honda or mitsu. "

just curiouos why you would say somthing like that? vvt would work wonders for a boosted motoer and most new motors have that feature. its not a honda or mitsu thing unless you meant to say vtec.

[PeterC]

VVT? No if you're looking for that snag up a honda or mitsu.

False...the MZR does have variable valve timing. Pretty much every good engine these days does, and our turbo version of the MZR is one of Ward's 10 best engines.

Here is some info on the base non-turbo MZR 2.3:
http://www.mazdausa.com/MusaWeb/displayPage.action?pageParameter=mazdaSpeedDriving EngineCommon&sectionParameter=engine01

You can also go here and click on the "Engine & Mechanical" tab to see VVT listed in the spec for our turbocharged MZR engine:
http://www.mazdausa.com/MusaWeb/displayPage.action?pageParameter=modelsSpecs&vehicleCode=MS3

[flipstylex]

Wrong !!!! , what r u guys talking about, this engine do got vtak on it. i hear it all the time on high rpm, thats when my vtak kicks in, shit, this is the best vtak engine eva made.










lol jk, just admiring the good ol days with the vtak :-)

[Sierra117]

I think it might have pistons. Not sure though. Cylinders. Definately cylinders.

[NCZ13]

I think it might have pistons. Not sure though. Cylinders. Definately cylinders.

your an idiot. all mazdas are rotary.

[Sierra117]

your an idiot. all mazdas are rotary.

On another forum I belong to (non-vehicle specific), and this is an exact quote from another member.


I was pulling out of school the other day, and another student has a Mazda. It has a V6 badge on the back. I thought all Mazdas were rotary powered. Is he just a huge ricer?


True story. Le sigh.

[Haltech]

With a conservative tune, this motor should easily hold 450hp to the wheels.

[Captain KRM P5]

there are oil squirters in this engine.

the rods are cast, the pistons are cast, the crankshaft is forged. same as every piston mazda engine before it, sorry guys. see the attached pictures below. if people want pictures of the pistons as well i have those.

left - factory cast iron mazdaspeed DISI rod
middle - eagle forged rod for 2.3
right - factory cast iron mazda protege rod :) bent :)

[tru-boost]

i'll be damned.... yep those are cast !!

[VermZ06]

This will tell you everything about the flippin' 2.3 disi turbo engine...
http://media.ford.com/mazda/article_display.cfm?article_id=24323

Creating the DISI Turbo engine involved more than just changing the injection system and adding a turbocharger, though. The form and materials used for the major components are optimized to bear the added load and heat of the increased output. The aluminum cylinder block and cylinder head are made using a new implementation of the Mazda Advanced Precision Casting process, which increases their strength. In addition, cross drilling between the cylinder liners and between the valve bridges in the head improves coolant flow and heat resistance. The crankshaft and connecting rods are made of forged steel, wrist pins are a new full-floating design, connecting rods have an optimized shape and larger journal size, and pistons are designed for maximum stiffness and durability.

[Captain KRM P5]

This will tell you everything about the flippin' 2.3 disi turbo engine...
http://media.ford.com/mazda/article_display.cfm?article_id=24323

Creating the DISI Turbo engine involved more than just changing the injection system and adding a turbocharger, though. The form and materials used for the major components are optimized to bear the added load and heat of the increased output. The aluminum cylinder block and cylinder head are made using a new implementation of the Mazda Advanced Precision Casting process, which increases their strength. In addition, cross drilling between the cylinder liners and between the valve bridges in the head improves coolant flow and heat resistance. The crankshaft and connecting rods are made of forged steel, wrist pins are a new full-floating design, connecting rods have an optimized shape and larger journal size, and pistons are designed for maximum stiffness and durability.

the rods are not forged steel, i am sorry. the article is incorrect. we have disassembled three of these engines. all of them have had cast rods, with casting marks in them. they are definetely an iron rod as well. the bore for the crankshaft and wrist pin are machined, but the rods are cast. forged rods are made through a pressurization process that does leave the type of surface shape or texture that a cast rod does.

[6262MS3]

I love how even the old N/A KL V6 in my '93 626 had a forged crank. What I'd like to know is why mazda chokes off the boost/throttle plate at high rpm? Can the turbo not flow efficiently above 5500rpm? Are they just tuning extra-paranoid to avoid another warranty fiasco (like the FD RX7)? I love the torque, I just wish the engine wouldn't fall on it's face so early. That would make running through the gears a bit more enjoyable.

[Captain KRM P5]

Are they just tuning extra-paranoid to avoid another warranty fiasco (like the FD RX7)? .

they'll never say that publically, but i'd say that has alot to do with it. why do you think we've never seen a 'mazdaspeed rx-8' ?

[Fritch]

the rods are not forged steel, i am sorry. the article is incorrect. we have disassembled three of these engines. all of them have had cast rods, with casting marks in them. they are definetely an iron rod as well. the bore for the crankshaft and wrist pin are machined, but the rods are cast. forged rods are made through a pressurization process that does leave the type of surface shape or texture that a cast rod does.

article is correct, they are forged. Not all forged rods look like what you show in your post, common misconception. Forged rods can look like cast rods as well, that doesn't automatically make them cast...

[VermZ06]

the rods are not forged steel, i am sorry. the article is incorrect. we have disassembled three of these engines. all of them have had cast rods, with casting marks in them. they are definetely an iron rod as well. the bore for the crankshaft and wrist pin are machined, but the rods are cast. forged rods are made through a pressurization process that does leave the type of surface shape or texture that a cast rod does.

The article is most definitely correct...its from Mazda's corporate website. I think they know better than anyone exactly how their engine is manufactured. Plus the engine is a four popper making 280 ft lbs of torque! If you want a four cylinder to have any sort of long term life expectancy with that kind of power you need to make one hell of a strong engine which is why mazda's 2.3 disi mzr and even the new caliber srt-4 have forged parts that make up the engine.

And I've found no proof of VVT in the 2.3 disi mzr..our engine's power band drops off significantly at around 5500 rpms...if anyone can show me any proof of VVT in our cars please let me know as my ms3 certainly didn't come equipped with it. The same thing goes for oil squirters...no where have i read that our engines have this and maybe i'm wrong but i'd compare that to a dry sump oil system that are on many high performance autos like the new vettes...maybe i'm wrong though since 'oil squirters are on the new srt-4...

[Betelgeuse]

I think it might have pistons. Not sure though. Cylinders. Definately cylinders.

hahaha, yeah you forgot to mention, valves, rods and don't forget the crank!!

[Fritch]

The article is most definitely correct...its from Mazda's corporate website. I think they know better than anyone exactly how their engine is manufactured. Plus the engine is a four popper making 280 ft lbs of torque! If you want a four cylinder to have any sort of long term life expectancy with that kind of power you need to make one hell of a strong engine which is why mazda's 2.3 disi mzr and even the new caliber srt-4 have forged parts that make up the engine.

And I've found no proof of VVT in the 2.3 disi mzr..our engine's power band drops off significantly at around 5500 rpms...if anyone can show me any proof of VVT in our cars please let me know as my ms3 certainly didn't come equipped with it. The same thing goes for oil squirters...no where have i read that our engines have this and maybe i'm wrong but i'd compare that to a dry sump oil system that are on many high performance autos like the new vettes...maybe i'm wrong though since 'oil squirters are on the new srt-4...
ugh again, VVT doesn't necessarily mean high rpm power. Its not like Honda's VTEC, its variable valve timing and yes your MS3 does have it.

[SwampAss]

That's great that you say that the engine has vvt...but where's your proof?


How much do you need?

http://www.motortrend.com/cars/2007/mazda/mazdaspeed3/specifications/


http://www.internetautoguide.com/car-specifications/09-int/2007/mazda/mazdaspeed3/index.html


Hell, it's on page 8 of the sales brochure:

http://www.who -sells-it.com/images/catalogs/784/pdf_9324.pdf remove space

[VermZ06]

I've been proven wrong...:( I'll admit it

[VermZ06]

this is straight from wikipedia...so take it for what it's worth...although technically this engine is continuous variable valve timing

The MZR is Mazda's latest Straight-4 gasoline powered engine. Development was assisted by Ford, who also sell the engine as the Duratec. The MZR family features a special long intake manifold for added torque, S-VT continuous variable valve timing, and a stainless steel 4:1 exhaust header.

Mazda S-VT - Varies timing by rotating the camshaft.

[6262MS3]

I think people are confusing vtec's cam phasing with variable valve timing. vtec actually slides the cam over to a different, high rpm cam lobe. This switching from a low rpm lobe to a high rpm lobe is what creates the whole "vtec just kicked in, yo!". vvt changes the timing of the camshaft without switching to a different lobe, these timing changes allow a broader torque spread and better fuel economy. Newer honda engines have both. The power drop-off on our cars has nothing to do with the cams, mazda's ecu tuning cuts the boost and starts closing the throttle plate above 5500rpm, presumably to make the engine harder to blow up.

[Captain KRM P5]

article is correct, they are forged. Not all forged rods look like what you show in your post, common misconception. Forged rods can look like cast rods as well, that doesn't automatically make them cast...

i have sent the rods out for inspection by more than just my own eyes. they are definetely cast. there are even casting marks on the individual rods.

regardless of that, every forged rod i have dealt with looks pretty much like what i posted, with the exception of I-beam VS A-beam VS H-beam.

[Captain KRM P5]

The article is most definitely correct...its from Mazda's corporate website.

mazda's usa website also states that the flywheels are interchangable between the mazdaspeed and non mazdaspeed 2.3s. been there, done that and proven thats not true either. even mazda can make errors.

http://www.mazdausa.com/MusaWeb/speedDisplayAccessoryDetail.action?endModelYear=20 06&speedAccessoryId=37&carLineCode=MZ6&startModelYear=2004&categoryId=3

not even close to being the same part. keep in mind now, i'm not trying to come across like a jerk, but i'm pretty hard to convince as a person who has pulled a bunch of these engines apart already and handled the parts personally. and we've pulled them apart mind you because connecting rods have snapped, curled or bent. i'll happily take the internals i have to any machine shop or mazda master tech and have him confirm or deny.

[SwampAss]

I have to side with Ken on this one. He's pulled the motors apart and has seen first hand what comes out.
Manufacturers aren't noted for being the most accurate when it comes to description. Even if the mistakes are honest.

[dkswim]

here is a good sight for you to check out. http://www.sportcompactcarweb.com/features/0610sccp_2007_mazdaspeed_3

[redrocketz]

if the engine was soo strong they wouldn't need to take away all the power from the top of the rpm range would they...

I have disassembled these engines and can say honestly I don't think these are forged rods I've built many of engine and seen many different forged intrernals and none look like those.

[dkswim]

the loosing power at the top is a ford thing it happens on ford focus and other ford cars. its a safety issue to keep from over reving the hell out of it. most of the stress on an engine is from rpms not boost.

[Fritch]

i have sent the rods out for inspection by more than just my own eyes. they are definetely cast. there are even casting marks on the individual rods.

regardless of that, every forged rod i have dealt with looks pretty much like what i posted, with the exception of I-beam VS A-beam VS H-beam.

a lot of manufactures that have forged rods as OEM, will look like that. Specifically GM rods, they almost always look like cast rods even if they are forged.

Research it some more and you'll see. However I do agree that most aftermarket rods do look like what you posted.

[nig3]

they are forged rods, they just arent machined all pretty like the aftermarket ones. check this shit--->> http://www.cardomain.com/ride/2230297

[nig3]

I think people are confusing vtec's cam phasing with variable valve timing.

UUUHHHH vtec has nothing to do with cam phasing, vtec is only cam lift!!! Cam phasing or timing is vvt only!!! Unless you have both like the new i-vtec motors, or toyotas 2zz-ge ect.... . Most new motors come with vvt, not vtec. and yes the MS3 motor does in fact have VVT.

[Young Roids]

The MS3 has the valve timing on the intake cam only.

[Boother]

I had to bring this back to put this mis-information to rest.

The stock rods are forged! Forged rods still have rough surface finishes and a rough parting line that can be mistaken for a casting parting line.

Here are some pitures of factory forged, aftermarket forged and aftermarket fully machined forged rods....

Factory forged.
http://images.hotrod.com/techarticles/p157192_image_large.jpg

Aftermarket forged.
http://images.hotrod.com/techarticles/p157193_image_large.jpg

Aftermarket machined forged.
http://images.hotrod.com/techarticles/p157194_image_large.jpg

[VermZ06]

The stock rods are forged! Forged rods still have rough surface finishes and a rough parting line that can be mistaken for a casting parting line.

Good to know...thanks for reopening this because I don't think this issue was ever settled. This makes me feel much more confident in the DISI...

[BlackCherry06]

Don't be over-confident :-)

http://i87.photobucket.com/albums/k133/bmman93/PICT0001.jpg

[VermZ06]

Yikes (sick)

[2.0t03speed]

subbin for later use

[ptrautne]

Don't be over-confident :-)

http://i87.photobucket.com/albums/k133/bmman93/PICT0001.jpg

The parting line is a sure sign that’s it’s a forged part. When the parting line is wide like that it’s a forged part because the dies that form the part can never touch. The cast part will have the parting line in the same spot but will be skinny because it will either be an overflow or a gate for the material

[Boother]

The parting line is a sure sign that’s it’s a forged part. When the parting line is wide like that it’s a forged part because the dies that form the part can never touch. The cast part will have the parting line in the same spot but will be skinny because it will either be an overflow or a gate for the material


Exactly what I was going to add.

Forged parts can still break when pushed too hard or if they have a manufacturing flaw.

[PeterSellers]

Thank you for adding this info about the forged rods...I am starting to get really sick of people spreading these rumors around about the rods being cast.

[GoFast]

this is one the instances i intended this thread for...

http://www.mazdas247.com/forum/showthread.php?t=123704139

[Captain KRM P5]

Thank you for adding this info about the forged rods...I am starting to get really sick of people spreading these rumors around about the rods being cast.

i guess the machine shops, engine builders, rod manufacturers who have verified for me and a few other vendors that the rods are not forged are either incompetent or spreading rumors. i guess the casting numbers on the side of the rod aren't an indicator either. i guess the fact that mazda has blatantly mis-stated or lied on thier own corporate website about mazdaspeed parts doesn't matter either. i guess the fact that my protege rod looks identical to that 'forged' part and its not forged at is mere coindence.

but hey, i'm only guessing here :)

my final guess is this; i would guess that anyone who wants to make real power on these engines wouldn't want to have these particular rods inside of it - regardless of if you think its forged, cast or fisher-price plastic. real speed, real horsepower does not come cheap. lets argue for the moment that the rods are forged. congratulations, you still have weak thin I beams that haven't shown themselves to be any stronger once you start seriously modifying the car. if just thinking that they are "forged" helps restore false confidence in how strong this motor is, then by all means sleep better at night, crank up the boost and go to town.

fact is, nearly everyone with blown motors has had a rich air/fuel ratio, not lean, a safe EGT, not overly hot - a real strong forged rod shouldn't do that. i can see a piston giving out under too much load, or even a crank. facts are facts - its always the rods first. it doesn't matter how the rods are made, it doesn't matter what they are made of. they are not bulletproof, they really aren't even all that strong and shouldn't be relied on when you have people snapping rods even on bone stock cars, on the street for no freak reason whatsoever. granted, this is oversimplifying and there are more variables, but how many times - when you have perfect AFRs, good EGTs and no detonation mind you - should you see a strong well designed forged rod snap and punch through your cylinder block?

so - manufacturing arguments aside - if just knowing in your heart of hearts that these rods are forged is enough to instill supreme confidence, i wish you the best of luck.

[Boother]

i guess the machine shops, engine builders, rod manufacturers who have verified for me and a few other vendors that the rods are not forged are either incompetent or spreading rumors. i guess the casting numbers on the side of the rod aren't an indicator either. i guess the fact that mazda has blatantly mis-stated or lied on thier own corporate website about mazdaspeed parts doesn't matter either. i guess the fact that my protege rod looks identical to that 'forged' part and its not forged at is mere coindence.

If you have more pictures showing the parting line and the "casting" numbers, please post them.

Have these sources of yours done any tests on the material or are they just eyeballing the stock rod and assuming?

[PeterSellers]

i guess the machine shops, engine builders, rod manufacturers who have verified for me and a few other vendors that the rods are not forged are either incompetent or spreading rumors. i guess the casting numbers on the side of the rod aren't an indicator either. i guess the fact that mazda has blatantly mis-stated or lied on thier own corporate website about mazdaspeed parts doesn't matter either. i guess the fact that my protege rod looks identical to that 'forged' part and its not forged at is mere coindence.

but hey, i'm only guessing here :)

my final guess is this; i would guess that anyone who wants to make real power on these engines wouldn't want to have these particular rods inside of it - regardless of if you think its forged, cast or fisher-price plastic. real speed, real horsepower does not come cheap. lets argue for the moment that the rods are forged. congratulations, you still have weak thin I beams that haven't shown themselves to be any stronger once you start seriously modifying the car. if just thinking that they are "forged" helps restore false confidence in how strong this motor is, then by all means sleep better at night, crank up the boost and go to town.

fact is, nearly everyone with blown motors has had a rich air/fuel ratio, not lean, a safe EGT, not overly hot - a real strong forged rod shouldn't do that. i can see a piston giving out under too much load, or even a crank. facts are facts - its always the rods first. it doesn't matter how the rods are made, it doesn't matter what they are made of. they are not bulletproof, they really aren't even all that strong and shouldn't be relied on when you have people snapping rods even on bone stock cars, on the street for no freak reason whatsoever. granted, this is oversimplifying and there are more variables, but how many times - when you have perfect AFRs, good EGTs and no detonation mind you - should you see a strong well designed forged rod snap and punch through your cylinder block?

so - manufacturing arguments aside - if just knowing in your heart of hearts that these rods are forged is enough to instill supreme confidence, i wish you the best of luck.

Can you point out where I said that just because these rods were forged, that I thought they would somehow instill "supreme confidence" in the strength of the motor? I've seen the rods, and they are indeed quite thin, but that is irrelevant to the argument at hand. I'm not dumb enough to think that just because a rod is forged, that it is somehow unbreakable.

I also think that you cannot accurately say with any certainty that "nearly everyone with blown motors has had a rich air/fuel ratio, not lean, a safe EGT, not overly hot". You simply do not know that. One of the main reasons why I think our motors are failing is because of our bizarre ecu that likes to adjust fuel delivery and alter A/F ratios widely when temperatures begin to change (at least, and possibly during other scenarios too, who knows). People have gotten the car tuned with a safe A/F ratio, and then found out later through datalogging that they are running a full point or more leaner during cold weather. The real fact is, this ECU is quite complex, and coupled with DI, we have a bit more to learn before we have truly figured out this engine.

[ptrautne]

Why do you think numbers on the part will say if its cast or forged (you think they cant forge the numbers)? The easiest way to tell if a part is forged it to look at the parting line of the tool. Compare the parting line of your protege and the MS3, do they look different? The other issue you’re going to have is some aftermarket companies consider parts machined from a solid block of material “forged” but you don't get the strength benefit of a true forged part (aligned grain structure and slight higher hardness if no other heat treatment is done). Also cast parts can be strong as long as you can insure there will be no porosity in critical areas of the design which can be can be very difficult.



i guess the machine shops, engine builders, rod manufacturers who have verified for me and a few other vendors that the rods are not forged are either incompetent or spreading rumors. i guess the casting numbers on the side of the rod aren't an indicator either. i guess the fact that mazda has blatantly mis-stated or lied on thier own corporate website about mazdaspeed parts doesn't matter either. i guess the fact that my protege rod looks identical to that 'forged' part and its not forged at is mere coindence.

but hey, i'm only guessing here :)

my final guess is this; i would guess that anyone who wants to make real power on these engines wouldn't want to have these particular rods inside of it - regardless of if you think its forged, cast or fisher-price plastic. real speed, real horsepower does not come cheap. lets argue for the moment that the rods are forged. congratulations, you still have weak thin I beams that haven't shown themselves to be any stronger once you start seriously modifying the car. if just thinking that they are "forged" helps restore false confidence in how strong this motor is, then by all means sleep better at night, crank up the boost and go to town.

fact is, nearly everyone with blown motors has had a rich air/fuel ratio, not lean, a safe EGT, not overly hot - a real strong forged rod shouldn't do that. i can see a piston giving out under too much load, or even a crank. facts are facts - its always the rods first. it doesn't matter how the rods are made, it doesn't matter what they are made of. they are not bulletproof, they really aren't even all that strong and shouldn't be relied on when you have people snapping rods even on bone stock cars, on the street for no freak reason whatsoever. granted, this is oversimplifying and there are more variables, but how many times - when you have perfect AFRs, good EGTs and no detonation mind you - should you see a strong well designed forged rod snap and punch through your cylinder block?

so - manufacturing arguments aside - if just knowing in your heart of hearts that these rods are forged is enough to instill supreme confidence, i wish you the best of luck.

[Boother]

I also think that you cannot accurately say with any certainty that "nearly everyone with blown motors has had a rich air/fuel ratio, not lean, a safe EGT, not overly hot". You simply do not know that.

Or like the Celica and RSX (or ANY manual car for that matter), with their close gated shifters, a simple mis-shift that overrevs the engine can lead to premature rod failures very easily. How many people have blown their engines? Has anyone even asked if they have ever mis-shifted?

[Captain KRM P5]

Or like the Celica and RSX (or ANY manual car for that matter), with their close gated shifters, a simple mis-shift that overrevs the engine can lead to premature rod failures very easily. How many people have blown their engines? Has anyone even asked if they have ever mis-shifted?

mrlilguy mis-shifted from 6th to 2nd on the freeway and threw a rod through the side of his block.


Can you point out where I said that just because these rods were forged, that I thought they would somehow instill "supreme confidence" in the strength of the motor? I've seen the rods, and they are indeed quite thin, but that is irrelevant to the argument at hand. I'm not dumb enough to think that just because a rod is forged, that it is somehow unbreakable.

i wasn't referring solely your remarks, sorry if thats what you thought i was doing



I also think that you cannot accurately say with any certainty that "nearly everyone with blown motors has had a rich air/fuel ratio, not lean, a safe EGT, not overly hot". You simply do not know that. One of the main reasons why I think our motors are failing is because of our bizarre ecu that likes to adjust fuel delivery and alter A/F ratios widely when temperatures begin to change (at least, and possibly during other scenarios too, who knows). People have gotten the car tuned with a safe A/F ratio, and then found out later through datalogging that they are running a full point or more leaner during cold weather. The real fact is, this ECU is quite complex, and coupled with DI, we have a bit more to learn before we have truly figured out this engine.

i simply do know that. its not rocket science that a car runs leaner when it is cold outside. or leaner when you are at different altitudes, or richer when you have hotter coolant temps, etc etc. this by the way has nothing to do with the fact that the engine is direct injection. the ECUs are programmed to run rich from the factory prior to any of us tuning the car because of variations in altitudes, temperatures and other environmental conditions. what the wideband or datalog says on a hot dyno on a summer day should never reflect what it would say on the road in wintertime. ECUs use input from the sensors to make fuel and timing map changes and the correction factors are going to be widely variable from Mazda. again, being direct injection has nothing to do with it and it should not surprise any experience tuner to get different wideband readings or EGTs when you go from one climate to the next. thats part of the reason many people have summer tunes and winter tunes. what you are doing is not only adjusting the map, but how well the correction factors in that ECU adjust on top of that map. its really a misnomer and misconception that there is so much different when it comes to tuning these motors. direct injection has been on the market in german cars for over three years now, and in other cars even longer. there are dozens of companies tuning those cars. the only reason the mazda market isn't getting that support is because frankly, there isn't nearly enough volume in this market to draw those companies in.

we've talked to everyone we are able to who has blown one of these motors. without fail nearly everyone, whether it be an owner or a shop, of them reports that the AFRs were rich under load and the EGTs were normal. this should also dispel the notion - and i have seen numerous people throw this out there - that you can run alot leaner on these motors than on standard injection motors. i tune for 11 or 12 to one on alot of boosted engines and these engines have blown under richer conditions than that. are there people who have probably blown thier motors other ways? i am sure there are. the overwhelming majority i have dealt with has not been outside that grouping.

all "are they or aren't they" arguments aside, the rods are a weak link in this motor when you want to make serious numbers and regardless of how or what they are made of doesn't change the fact that they're inherently weak. good to 350whp? maybe. good past that? i wouldn't bet on it.

[PeterSellers]

i simply do know that.


So what you are saying is, you have datalogs of "almost every" motor that has blown, at the exact time that it blew, that shows a rich AFR at the RPM range that the failure occured and with low EGTs? I find that hard to believe.



what the wideband or datalog says on a hot dyno on a summer day should never reflect what it would say on the road in wintertime. ECUs use input from the sensors to make fuel and timing map changes and the correction factors are going to be widely variable from Mazda.


Agreed. However, when a person who claims that his motor blew running only 11:1 AFR, is he basing this number off of a previous reading he took off the dyno, or what? Like you said, the correction factors that the ECU will implement are widely variable from Mazda, so at the time of motor failure, their AFR's likely weren't what they thought they were. Also, when someone throws out an AFR number like that, what point on the curve exactly are they referring to? It's widely known that the CDFP cannot deliver as much fuel in lower RPM's, resulting in higher AFR's right around the time the turbo begins to fully spool. That alone is a potentially dangerous condition for these motors.



all "are they or aren't they" arguments aside, the rods are a weak link in this motor when you want to make serious numbers and regardless of how or what they are made of doesn't change the fact that they're inherently weak.


I'm not trying to argue about whether or not the rods are the weak link or not, as that definitely seems to be the case. All I'm stating is that the rods are forged, and that there is not enough evidence to assume otherwise. That's it. For some reason, that is getting interpreted as "I think these rods can handle 400+whp with no problems". Maybe with a properly tuned car they can, who knows, but it hasn't happened yet (then again, I haven't seen any built DISIs with 400+whp either)

[Captain KRM P5]

So what you are saying is, you have datalogs of "almost every" motor that has blown, at the exact time that it blew, that shows a rich AFR at the RPM range that the failure occured and with low EGTs? I find that hard to believe.

i have seen quite a few. what you want to believe/question my credibility or honesty is up to you.




Agreed. However, when a person who claims that his motor blew running only 11:1 AFR, is he basing this number off of a previous reading he took off the dyno, or what? Like you said, the correction factors that the ECU will implement are widely variable from Mazda, so at the time of motor failure, their AFR's likely weren't what they thought they were. Also, when someone throws out an AFR number like that, what point on the curve exactly are they referring to? It's widely known that the CDFP cannot deliver as much fuel in lower RPM's, resulting in higher AFR's right around the time the turbo begins to fully spool. That alone is a potentially dangerous condition for these motors.

i've already asked what the conditions were at the time the motor blew. i cannot say i know of one that blew in the low rpm lean spot - which you will find is not entirely the cause of the fuel pump either. i am not saying that customer x was running 11:1 on the dyno, went out on the street not knowing what they were running for an AFR and then blew the motor. i am saying they knew, at time of failure, what the AFR was and what the operation condition was. i have had a few people with thier eyes on thier widebands/dashhawks/etc see the AFR in real time as the failure occured. you are also misinterpreting what i said about the correction factors and AFRs somewhat. but to summarize, no i am not saying people blew thier motors at point B and knew only what the AFR was at point A. i'm fully aware the kind of sense that wouldn't make.

i disagree that an initial lean spot as the turbo initially spools is detrimental. its quite common to see tuners run a mid 13:1 AFR as you initially pass zero PSI, but only briefly. some people may not consider this truly 'lean' by nature.




(then again, I haven't seen any built DISIs with 400+whp either)

there really are only a half dozen built DISIs out there that i can speak of, mostly in mazdaspeed6s. you will see it, but those people will breaking alot more than motors on the way to that number.

[mrlilguy157]

my motor popped without any load whatsoever, about 1350 Fahrenheit EGT's, no boost at all. a mis-shift/over-revving will do that to you.

oh well - forged here I come, thanks ken! The motor will be built an in a mazdaspeed 3 with a spec clutch and big turbo, and some sort of tuning (undecided at the moment)