Flyin' Miata : Dissecting the Mazdaspeed MX-5

[general default]

They take it a part and will be doing dyno testing in the next week with reports. Lot more changes than I thought. See how big the intercooler really is. Read more...

Guess I am the last to know that the Miata name is no longer going to be used. "Yes, it's an MX-5 and not a Miata. Thanks to a lawsuit from a bicycle manufacturer, there won't be any more Miatas. Just MX-5s."

[sammm]

Guess I am the last to know that the Miata name is no longer going to be used. "Yes, it's an MX-5 and not a Miata. Thanks to a lawsuit from a bicycle manufacturer, there won't be any more Miatas. Just MX-5s."

I noticed that last week when I saw rx7gsl's new MSM. Just an MX-5 emblem on the rear end, no Miata tag anywhere to be found.

[POS Racing]

Guess I am the last to know that the Miata name is no longer going to be used. "Yes, it's an MX-5 and not a Miata. Thanks to a lawsuit from a bicycle manufacturer, there won't be any more Miatas. Just MX-5s."

No I guess I am! What ya talking about Willis? No more Miata after almost 15 years!

[rx7gslse]

its' only the Miata here in the US..

it's the roadseter or Euno roadster everywhere else already...


And yeah, I know they've got one.. I've already talked with Keith and asked him to check on a coupel specific things

[Miatamaniac92]

What are you current plans, exhaust, intake, boost controller?

I'm curious how quick that intercooler heat soaks.

I wonder if FM is gonna try to put their bigger intercooler on with another 10 feet of piping also.

Chris

[rx7gslse]

plans?

full 2.5" exhaust with wideband setup. (probably teh AEM)

Intake? TBD.. whatever I can figure out that makes the most power.

Intercooler? Probably just a wider front mount and use most fo the stock piping.

I still don't know yet what the ECU wwill do with any of those mods, so plans for electronics & fuel system will be dependant upon what that does. (the reason for the wideband)

[Miatamaniac92]

Are you gonna wait for the expensive FM exhaust or go custom?

Intake should be a pretty easy mod with plenty of benefits, especially b/c it's turbo. The current intake is going to act like a restrictor plate ALA WRC at higher HP and/or current HP.

Chris

[rx7gslse]

yeah, it shouldn't be hard to do an intake, only problem is there is a hard metal pipe that locates the afm where it is...

It's the same basic afm, so I'd like to use the cold air box style intake.. Kinda like these boxes
http://www.good-win-racing.com/goodwinracing_003.htm

On the Exhaust? I might buy a ready made cat-back system, but I'll end up going custom for the downpipe & midpipe I'm sure. It'll probably flow better and cost less. The catback is dependant upon the muffler a lot for power & sound, so I might trust that they know what they're doing there...

Hate to go thru the effort to get a custom catback only to have it sound like deep fried a$$.

[tailchaser]

You may want to borrow my OBD data logger before going for the cold air intake unless the intake point is a lot different than the other '01+ cars...

My intake temp (measured near the throttle body as far as I can tell) rarely exceeds ambient + 10 unless the vehicle has been run hard and immediately shut down...

[rx7gslse]

nope.. in fact, the airbox is the same and in the same location as on the non-turbo cars.. I just assumed that someone had already looked into the ideal way of getting cool air into the car...

I just hear back fro the K&N guys.. They've got their system design done for the car already, but it's still 4 month out form market.. (I can only assume the intake pipe has to be molded)

blast...

[tailchaser]

As I said, you're welcome to borrow my data-logger and do some testing... I'll be curious to see what the hair dryer does to the intake temps...

[rx7gslse]

never used a data logger before....

what does it log? I'm interested :)

[Miatamaniac92]

Intake temps @ the TB are highly dependent on both the intake and intercooler. It goes as follows:
A higher intake temp(A) adds to the delta temp increase of the turbo (based on the effeciency of the compressor wheel at a certain CFM, see compressor chart in previous post), which increases the amount of temp the intercooler has to take out of the intake charge, which causes the intercooler to heat soak quicker.

As you can see the intake temp is the starting point for the entire intake plumbing temp. Consequently, minimizing the difference from ambient will keep the intercooler from heat soaking as fast.

I don't think this much matters until you increase the boost/ HP. Mazda did what looks like an "adequate" job for the masses.

If it were me, and I had the money; I would upgrade everything and say screw the warranty. If I leased the car, I would bolt on an exhaust.

Also though, intake and exhaust is easy to change out at warranty time.

Hmmm, I guess this is enough rambling. I'l try to get back to work.


Chris <---Just thinking out loud

[tailchaser]

never used a data logger before....

what does it log? I'm interested :)

23 of the OBD-II data points... Probably of interest would be intake temp, MAP (I assume this is enabled on the turbo, though it is not on my car). The resolution is piss-poor at 5 seconds, but it can be interesting, and doesn't require strapping a laptop into the car.

I've got the ability to log data in Volkswagens at 3Hz or better... I'm waiting on the OBD-II guy to get back from spring break so I can pick up the software to run on my laptop and see if resolution gets any better with a laptop doing the logging.

[Majik]

Just to respond to the questions about the intake temps. As far as I know the OBD-ii on this car takes the intake temp at the intake temp sensor which on a stock car is in the airbox, not at the throttle body. If it is this way on the turbo, then the intake temps are going to change as it is before the turbo when the temps are recorded...

[general default]

Here is flyinmiata's first MSM dyno results with an exhaust change.
The info came from this link.
http://dauntless.milewski.org/wws/ar.../msg01147.html

From: Bill Cardell <[email protected]>

To: "'[email protected]'" <[email protected]>

Subject: And what everyone has been waiting for....

Date: Fri, 23 Apr 2004 16:28:24 -0600

Drum roll. Numbers all over the place, I think due to the teeny intercooler.
Best cool run 153hp/147 lb/ft, corrected by 1.2. 20% is the average
correction our dynojet used.
Hp tended to drop by 3-5 hp each time the car was run. As an example, three
back to back runs went from 94kw/167 nm (uncorrected) to 87kw/157nm,
steadily dropping. Looks like rear FM muff gave about 2 hp, bolts right up,
tip needs a little lengthening to clear the rear fascia. Keith will post
pics Tuesday.
I'm out the door in a few minutes, so no more answers 'til Monday. The car
does feel really nice.

Bill Cardell (TurboDog's Dad)
[email protected]

[rx7gslse]

2 horsepower?

Whoo hoo! I've gotta spend my $400 on THAT.

or not. :)

[Miatamaniac92]

Ahh yes, but the sound alone is worth maybe 100 bucks, not HP.

Chris

[rx7gslse]

ok, you do have a point there... this thing is way too quiet

[rx7gslse]

ok, well FM just posted their dyno results..

The catback didn't really do anything...

Sounds like I'm just gonna have to go ahead with teh full exhaust then.