mprhead5

I noticed that some of the forum members here had come over to mazda-speed.com recently to I thought I would post up some common questions and issues on the Mazdaspeed and allow anyone to ask questions that wanted answers.


Common problems:

Stock diverter valve leaks from factory. This can cause many stock mazdaspeeds to have differant power levels when stock depending on how bad the leaking is. This is a number one priority replacement as the leaking can bleed off a lot of boost 1-3 psi. A drop in replacement is available from forge motorsports.

Stock intercooler is way too small and heat soaks after just a few pulls. this can have a large effect on power and can make dyno tuning the car very annoying as power will fall off after just a few runs. a EBAY 28x7x2.5 intercooler is an easy install but T-bolt clamps are needed at least on the tubing side or they will slip off and leave you stranded. the larger intercooler will stand up to race conditions without heat soak.

Stock ECU. This is the real weakness of the MSM. not all MSM's show problems but most do. you can feel the problem as the car will accel sluggishly up to 5,000 rpm then take off as the computer kicks into open loop. This can also cause a lean spot to appear prior to switch over. FM sells an O2 mod ( clamp ) that will fool the computer into kicking into open loop as soon as you go into boost which will vastly improve drivability and smooth out the power delivery.

Stock Throttle body inlet tube Has a tendency to slip off the throttle body under load and has also been known to crack. Replacement units are available from FM and BEGI

THE BOG!

this has been a mystery in the MSM community for some time and presents as a sudden bog of the engine that persists until the car is restarted. Not all MSM's have this problem but it is well documented. recent findings have possibly linked the bog to a sticking EGR valve but as I have never experienced the bog I don't have the answers.

ADDING POWER

The MSM responds much like any turbo car in that intake and exhaust upgrades make a large difference in the power of the car.

Downpipes. FM and BEGi both make good downpipes and yield 15-17whp. BEGI makes a separated downpipe that adds a little more than the single pipe designs but can overwhelm the wastegate on the stock turbo and cause boost creep if wastegate mods have not been done. Downpipes improve spool up a good bit, maybe 500 rpm's. You can also simply gut the stock DP for similar results if you don't care about emissions

Intakes. several companies make good intakes for the MSM. The injen should be avoided as it has been known to cause a CEL. and intake and boost controller up to 10.5 psi can produce 20whp

Catback. not a whole lot of power here but will still yield 3-7 whp and improve spool up maybe 200 rpms.

Intercooler. BEGI and FM make intercooler kits but an EBAY intercooler is just as good and costs a whole lot less. 28x7x2.5 is a common upgrade size for intercoolers and will stand up to race conditions without issue.

ECU/FUEL. The limitations of the stock ECU come into play as you finish the basic boltons. By that point you will be in the 190-200 whp range. you can go with 305cc injectors if you want a little more fuel and don't have the cash to spend on an ECU option or if you are experiencing detonation at that point. The 2 Major ECU options on the market that have been proven with the MSM are the Hydra EMS and the XEDE piggyback. Both work well the hydra is a full ecu and has much better functionality and can increase the rev limit beyond the meager 6500 rpm that Mazda gave us. Megasquirt is also on the market but is as yet an un proven yet promising option and offers cost savings at the expense of more demanding install and tuning.

TURBOS. There are more options that I can go through in any detail. I have a Bloushe upgrading installed on my car but the more common upgrade now is the one from deadbolt. Deadbolt offers many services and can even fix up the wastegate on the stock unit to remove boost creep issues. Full upgrades are available from BEGI and FM and there is not shortage of options. a compressor upgrade can get you to 230-255whp depending on type, fuel quality, tuning quality.

Clutch. The stock clutch is rock solid and if treated right will last into the 250whp range without issue

Tires. Traction becomes a huge problem when boosting power past the 220whp range. Falken azenis RT-615 215/40/17 work very well to keep traction in hand but past 230whp even the best street tire will show weakness.


This is just the basics but I hope it will answer some questions if anyone is interested.

Newbsauce

iTrader: (2)

I think alot of everything you said is pretty much common turbo knowledge on every car. Adding intakes and exhausts to turbo cars = horsepower. Ebay coolers are good. The MSM specific issues were nice though.

mprhead5

yea the bolt on stuff is universal but the other stuff is MSM specific. I am told that the BOG is in fact caused by a solenoid on the passenger fender up front that goes bad on some cars. what really has been a plesant surprise is how well the clutch holds up to power. with my 240whp my stock clutch is still working great

Braineack

iTrader: (62)

Can I see the data behind this "fact?"

Does the MSM have a MAP sensor? I can't even fathom this as the truth from a factory boosted Mazda....There is a factory boost cut right? So it must be read by a MAP sensor. I can't believe Mazda would fuel the MSM like they did the 323/626/MX-6 turbo, 15 years prior.


but most of this is standard universal turbo yibber yabber.

The_Pipefather

iTrader: (5)

I'm curious to see some real data too. And I don't mean the tests that FM did. Bell has said that the MSM factory intercooler is in fact a good choice up to 200 whp.

compy

Almost as bad as HDHCHTDD

msydnor

iTrader: (3)

Quoted from the BEGI site:

"With some minor modifications, this intercooler will directly replace the stock one. This intercooler is 32% larger and has 80% more volume allowing for cooler intake temperatures. In order to make your stock MazdaSpeed Miata more powerful, the intercooler upgrade is a must have".

I'm pretty sure stephenie will tell you the stock IC sucks. Although I do not have the dyno sheet any more, when dynoing the car with the stock IC, on a 90 degree day, I lost almost 10 rwhp by the 4-5th pull. With the upgraded IC in very similar condition on the same dyno, I lost 2-3.

msydnor

iTrader: (3)

There is one guy running a MS, it's a new install and seems to be working well for him. He did not remove the factory ECU, he left it in tact and is still using some of the function of the stock ECU's (not sure which ones). He calls it a hybrid setup. When I got my MSM, much of what people told me I wrote off as BS. Example the greddy EMU. Guys here run them with few issue on non MSM cars. On the MSM, several have tried and non have been very successful at making it work very well. People like Gary at track dog racing that has done a ton of non MSM EMU setups gave up in disgust. It made no sense in my mind why it shouldn't work on an MSM just as well as a miata with a DIY setup, but it doesn't.

Stephanie Turner

Actually, the intercooler is sized properly and it a well functioning piece from the factory. It is when you start modifying the car, or raising the boost, a larger intercooler may be necessary. Each intercooler size has a specific hp rating or hp is it capable of supporting. From the factory, the intercooler is perfect for 8 psi or 150 whp.

Any intercooler can heat soak on a dyno. Especially when it is hot outside.

My personal opinion on the car is: it is a good car, good suspension, nice drive-ability. But the turbo and the ECU suck. Replace the stock turbo and add the Xede, it is a sweet ride. Especially on a stock clutch. I would own one - under certain conditions.
Stephanie

msydnor

iTrader: (3)

Agreed, maybe I should have been more clear...past stock HP levels the factory IC sucks. Most MSM owners are at 180rwhp with a couple of simple bolt ons. BTW, I love my SGDP.

hustler

iTrader: (6)

I thought 3" exhaust helped out these cars more than that?

msydnor

iTrader: (3)

I'm assuming you are being sarcastic, but the MSM computer trully suck IMO.

hustler

iTrader: (6)

all your threads talk about how "my car is not a $2000 car." If you're in a state where emissions are part of life, then I'll take the $2000 car.

mprhead5

back in the day when I only had 175whp with an intake I would heatsoak after a few pulls on the way to work in phoenix. while the stock unit worked ok for the stock car, once you up the boost you are getting a good deal more heat and the weakness of the small unit comes out. I don't need any extra data because I have experianced the heat soak first hand and so have many others with this car.

as for the ecu i was simply listing the systems that work well with the car. anyone here is free to try other routes but headachs are most likly in your future if you do.

I have a lot of knowlage on this car since every part i installed myself and even took an active process in the dyno tuning. You all can beleave what you wish but my reputation with the mazdaspeed is well known in the community as is Msydnor's

msydnor

iTrader: (3)

It's not a $2000 dollar car, I only said that once...should I say it is to make you feel better?, and I do live in an emissions state. I also like $2000 cars. So what's your point other than attempting to be a dick? Oh, I forgot, your not a real person. My bad.

The_Pipefather

iTrader: (5)

And how did you know it heatsoaked? Measured before and after surface temperatures of the i/c with a pyrometer perhaps?

This heatsoak thing is something I don't understand. How the hell can a front-mounted IC open to the airstream heatsoak in any measurable way in normal road use?

Braineack

iTrader: (62)

This is something I have done....after a 15min session on the track, ambient temps were 86*F IIRC. 12x11x3" core IC. Inlet tube measured 95*, outlet 90*. sometime to that matter, that was a few years ago. I can believe too small (inefficient) , but I'm not a believer in heatsoak for a FMIC.

mprhead5

an intercooler as you know is a heat exchanger. it can remove heat from the air charge by pulling the heat out of the charge air and into the metal of the core which in turn is cooled by the air passing over the intercooler. Heat soak is when the charge air heat is so great that the heating effect of the charge air surpasses the cores ability to remove the heat. Thus the temp of the intercooler will continue to rise and sap power for the motor. When you up the boost the heat produced by the compression of the air goes up and surpasses the cores ability to remove the heat and you get loss of power caused by the heat soaked core.

Braineack

iTrader: (62)

During boosted pulls, the intercooler heats up (heat form the compressed charge is transfered to the aluminum IC); the compressed air is now cooler.

After the run, the now hot intercooler acts like a heat exchanger: it gives up its heat to the less-hot ambient air that is flowing over its fins. (Some crazy amount of ambient airflow like +2000CFM.)

When the intercooler can't shed its heat fast enough, before the next boost session, it won't cool the compressed charge as effectively as it could have, and this is what you are referring to as "heat soaked." The intercooler isn't doing as much good when its own temperature is too high.

The fact that an intercooler acts as a heat sink actually allows it to absorb the of heat, you want it to "heat soak." So, heat soak really only refers to an intercooler that hasn't cooled down since its last job. If your intercooler doesn't cool between a few pulls at +60mph, then I'd say there was a trash bag stuck on it's face.

So the solution would be to increase the rate at which the intercooler can shed its heat. Or like you said, slap in an intercooler that requires less airflow between runs to cool it back down and also can support greater airflow absorption rates. since most of you are increasing the base HP level, then this is probably a good idea. But to simply say "the IC heat soaks, replace it," isn't the whole story. What would be simpler thing to say would be: the IC was designed as the smallest IC to do an efficient job from the factory, thus when increasing the power output and boost level, it's a wise decision to upgrade to something more efficient at higher boost levels.

The_Pipefather

iTrader: (5)

But then, you don't need intercooling when you are off-boost, do you? The scenario you describe is true of any intercooler because that's how they work. A high Off-boost IAT is not of much consequence, I would think.