The Chances of blowing my motor.

[Lex]

Originally Posted by bf360 high rpm as in what, 8000rpm? so your saying 300hp at 5500rpm puts more load than 350ftlbs at 2500rpm in a high gear

Read the attached document. It explains the phenomenon much more thoroughly. It also shows that some myths are born in forums based on word of mouth.

[martyxattack]

what book is that from

[Lex]

Originally Posted by martyxattack what book is that from

Corky Bell's Maximum Boost.

[94jedi]

Originally Posted by Lex Corky Bell's Maximum Boost.

This is a must read for ANYONE in the turbo game. I own it and love that book. It's a bit technologically outdated now but the basic principles still apply and always will.

[94jedi]

Originally Posted by Lex This no WOT at low RPM business doesn't add up. You are putting a lot more "load" on the rotating assembly when you're WOT at high rpm. So unless someone intelligently explains this low RPM load issue instead of the usual regurgitating it because someone else said it, I wouldn't buy it.

to be honest, it never made sense to me either. I'm not mech eng. but I have read Max. boost and for the most part, understand the main points. The going up hills thing doesn't add up either....unless you mean going 70 up a hill in 6th and going WOT. Then, yes. But if you go wot up a hill in 3rd?

Seems like there's a lot of forum myths about why these cars blow and I'm positive that alot of it comes from the owners not wanting to own up to abusive driving habits.

[lidokrantz]

Grim;quote...don't even worry about blowing the motor,i beat my car hard like a redheaded step child and it has given me no problems.you are getting too paranoid man

indeed....paranoia..been there and i said "FUCK IT" and kept the Speed...drive correctly/keep the car at a reasonable power level/ 300whp tops, IMO, keep the rpms in the power range 3-6000 rpms and all should be ok.

--------------------------------------------------------------------------------
quote ...Gong Show
FWIW, I chatted with my local Mazda service manager yesterday. They have yet to see a MS3 come in with a blown motor. I know that doesn't mean a lot, but I think these are still VERY limited cases.

i was at my Mazda dealer that installed all my mods...and shazaaaaaaam Gomer...no blown Speed3 engines there as well....a replaced smoking turbo on a couple of Speed6's and all in all the Speed3 has been a reliable car stock or slightly bolted////you want more power than 300 whp then built it like Y2 mentioned, or take some chances and blame no one but yourself if something happens, otherwise less is more with this car if you want to be on the safe side...and i decided that i have 3 years left on my engine warranty...and being this car may be a little tempermental..LOL i am choosing the safe path and keeping things in balance and power at a stock/bolted level till my warranty is up. The will see...

[Lex]

Originally Posted by 94jedi to be honest, it never made sense to me either. I'm not mech eng. but I have read Max. boost and for the most part, understand the main points. The going up hills thing doesn't add up either....unless you mean going 70 up a hill in 6th and going WOT. Then, yes. But if you go wot up a hill in 3rd? Seems like there's a lot of forum myths about why these cars blow and I'm positive that alot of it comes from the owners not wanting to own up to abusive driving habits.

There are a couple of things that I can think of that can be a problem:

1. Lugging the engine at low RPMs when there isn't much oil flow results in poor lubrication under high stress on the bearings

2. A high amount of torque at low RPM can cause detonation, but this car pulls timing until after TDC (negative timing advance) for a reason when you spool up

3. The engine is moving so slowly that the rotating assembly is "hammered" on each power stroke due to low inertia of the assembly. You'd have to lug the engine pretty badly though.

If you're thinking about all this as an issue, then you should not get off the gas immediately at high RPM - the tensile forces become great on the rods very quickly under high vacuum.

[bf360]

The thing with these motors is no one has blown up full throttle really, i dont think anyone has pushed the limits of the motor yet.
whoosh had what, 386awhp on the mzr, and he never blew, neither did chris with his 35r, shit if whoosh had that motor in a speed 3 he would have dynoed over 400whp easy, while still on the stock block

So until someone blows up because of to much power and not creep, load, or open closed loop or whatever other bullshit is in the mazda ecu, no one knows the limits of the stock motor

[08_ms3_gt]

Originally Posted by Lex Read the attached document. It explains the phenomenon much more thoroughly. It also shows that some myths are born in forums based on word of mouth.

*smacks head*

fuuuuuuck i read that book. i've been brainwashed by the forums.

[DaleNixon]

Originally Posted by 94jedi to be honest, it never made sense to me either. I'm not mech eng. but I have read Max. boost and for the most part, understand the main points. The going up hills thing doesn't add up either....unless you mean going 70 up a hill in 6th and going WOT. Then, yes. But if you go wot up a hill in 3rd? Seems like there's a lot of forum myths about why these cars blow and I'm positive that alot of it comes from the owners not wanting to own up to abusive driving habits.

Can anyone recommend some good driving habits?

When I started with this car, I was getting to 6th gear as quickly as possible no matter what speed I was cruising at. Now I cruise in 3rd up to 30 and 4th up to 40. I shift into 5th at 45 and don't touch 6th until I'm going at least 60.

[GongShow]

For once, some great knowledge in this thread. Car forums are great places to sensationalize and parrot urban legends. As I've mentioned in other threads, CAI hydolocking, underdrive pulleys, motors blowing constantly, pop rocks and Coke making your stomach explode, etc...date back decades. This isn't Jerry Springer. You figure just about everyone on this board has modded their car to some degree. A lot know WTF they're doing but there are some that don't. You're going to see a few busted motors and those people are going to be ALL over this board about it. Most run just fine.



I've had many online chats with Corky as the BEGI folks are on the Miata forums quite a bit. He had convinced me to go turbo with my supercharged Miata. Very few people know as much about turbos as Corky.

[Sanch]

Hmm nice way to throw in my face smart guy. JK it is very uncommon to blow your motor haha. Guess we can answer the question of this thread. hahahaha

[y2kc0wb0y]

Originally Posted by bf360 The thing with these motors is no one has blown up full throttle really, i dont think anyone has pushed the limits of the motor yet. whoosh had what, 386awhp on the mzr, and he never blew, neither did chris with his 35r, shit if whoosh had that motor in a speed 3 he would have dynoed over 400whp easy, while still on the stock block

I've said to you in another thread already that you need to realize the learning curve you're dealing with here. These guys are very smart when it comes to this stuff. Back in the day guys were running 22 psi on stock SVT Focus blocks and pistons for years before they blew. Big difference is they now how to walk the razors edge. If you don't have that skill set...seriously back away from the WHP.

Originally Posted by Sanch Hmm nice way to throw in my face smart guy. JK it is very uncommon to blow your motor haha. Guess we can answer the question of this thread. hahahaha

This thread needs to die.

[bf360]

Originally Posted by y2kc0wb0y I've said to you in another thread already that you need to realize the learning curve you're dealing with here. These guys are very smart when it comes to this stuff. Back in the day guys were running 22 psi on stock SVT Focus blocks and pistons for years before they blew. Big difference is they now how to walk the razors edge. If you don't have that skill set...seriously back away from the WHP. This thread needs to die.

lol are you guna go around and pick on all my posts lol

honestly i know what your saying but it sort of proves my point in that most of the motors that blew were due to lack of knowledge/or other error as creep etc

[bf360]

Originally Posted by Sanch Hmm nice way to throw in my face smart guy. JK it is very uncommon to blow your motor haha. Guess we can answer the question of this thread. hahahaha

your motor is going to blow















might happen in 1000 miles might happen in 500000miles but its guna happen

[mexicant]

yep. 100% gonna blow up and kill 3 babies. you bought a mazda, not a well engineered car

[Lex]

Here's another read. Before bashing the DISI MZR engine, take a look at what it took to take a 2.2 litre Ecotec to the different power levels.

Also note that the engine blew stock at ~250crank hp when it was designed for 160 crank.

This sounds about right as the upper level that you can take a stock motor - around 50-60% above rated power.

This puts the MS3 stock motor at high risk anywhere above 400 crank hp if you're not being stupid about it. Considering 15% drivetrain loss, this makes the motor "safe" below 350whp.

No these numbers are not exact, but they give you an idea. I wouldn't ride 350whp, I would keep it around 300-320whp for longevity and a great reliable fun ride - again if you're smart about it.

Remember that wear in every form is accelerated as more heat and more force in placed on the assembly. No rod is meant to last for ever and no engine is meant to last for ever. Every material has a lifetime and a number of cycles it can go through before it yields.

[Tomas]

Originally Posted by y2kc0wb0y lean fuel pump conditions don't bend rods...they fry pistons or burn valves

+1

[Lvis]

Originally Posted by Lex No these numbers are not exact, but they give you an idea. I wouldn't ride 350whp, I would keep it around 300-320whp for longevity and a great reliable fun ride - again if you're smart about it.

what about 350 tq? (this is probabbly a stupid question i know but wouldnt the tq reach 350 before the hp)

[Lex]

HP is calculated from torque. It throws RPM in the mix. Our cars have higher torque numbers compared to hp. torque measures the real force applied to the components but hp establishes a relationship between how much torque you have at what RPM.

If you have 350 ft lbs of torque at 7000 RPM you'd have 466 hp.

[GongShow]

torque gets you there, hp keeps you there.

[cld12pk2go]

Maximum Boost = entry level knowledge to mod/build a turbo car.

I read it. Twice.

My background is chemical engineering, and I thought it was an excellent read.

The bottom line is that modding turbo cars requires significant understanding of the basic principles or epic fuckups can rapidly result.

Enjoy.

[94jedi]

Originally Posted by cld12pk2go Maximum Boost = entry level knowledge to mod/build a turbo car. I read it. Twice. My background is chemical engineering, and I thought it was an excellent read. The bottom line is that modding turbo cars requires significant understanding of the basic principals or epic fuckups can rapidly result. Enjoy.

My Audi A4 was my first turbo car (circa 2004). when I bought that car, first thing I did was go on an Audi forum and make a few stupid posts based on my supposed general knowledge of turbo's. I knew the very basics but nothing of what was in Max. Boost. Someone suggested I read that book before making a bigger ass of myself than I had already done. So I picked up the book and at least now I can somewhat defend myself lol. It's still a learning process for me though...everyday I learn something new. These cars are incredible in that no two behave the same way.