Modifying an SE

[Dre]

I did a bit of a search but got a few red herrings so I hope you don't mind me creating a thread.

I'm looking at getting an SE (just comparing it to an nc3), and I wonder what nuggets of wisdom you can offer on modifying it to a nice power output (nothing crazy).

I had my s15 built and tuned to 300rwhp so I have some basic knowledge on mechanics and modifying cars and I'm not afraid to spend some cash. What I don't want is a shoddy or unreliable car, which in my experience is often the case with turbos.

I see the mx5 mania stage 1 kit (2.5" exhaust, air pod, big front mount fitted for $2800) bumps power from 121kw (flywheel) to 145rwkw. This seems quite significant to me so I'm guessing the engine is very restricted from factory.

I read around a little bit and apparently the stock ecu has a boost cut over 10psi, and the fuel system maxes out quite easily. Also read that the blow off valve isn't much chop? A solid intake pipe (on the plenum?) seems to be popular too.

In my experience fitting a big front mount took away throttle response and messed with the tune on my s15, almost enough to warrant a retune.

If I was to skip the cooler and just go with a nice exhaust, pod + solid intake + bov, would I have decent performance?

And any thought on reliability of this car or comparison with an nc?

[ManiacLachy]

Plenty of info on upgrading the SE out there, but you'll find most people happy to help out here too.

Checkout FlyinMiata's Mazdaspeed Miata upgrade path: http://flyinmiata.com/tech/MSM_upgrades.php
And the Mazdaspeed Miata Forum: http://www.mazda-speed.com/forum2/
(FYI, in the US, the SE was called the Mazdaspeed Miata )

So yeah, you have it on the nose, Mazda strangled the engine on intake and exhaust, reducing the power significantly. An intake and 2.5" or 3" turbo back exhaust will see you breathing easier ... not 145kw, but better! Replace the throttle body inlet elbow, it's rubber and blows off easily, and while you're at it, replace the BOV which leaks. Speak to NitroDann on here, a forum sponser for a great bit of kit for these 3 bits - I did. A lot of people will also upgrade the intercooler, not for more power but because the postage stamp that pretends to be an FMIC in these cars will heat soak VERY quickly, it shouldn't noticeable affect your spool up.

At this point you could turn up the boost, but the ECU will be struggling, and it's a good idea to do the ECU if you want to go further. There's an option from Chiptorque to flash the ECU, which is great if you're ready to set it and forget it, but if you ever think you might make further mods to the power, you'll probably want to get a standalone ECU from Adaptronic, Haltech, or Megasquirt (or other). Injectors, boost control and a wideband should go in at the same time, making this an expensive jump, but a good one. It's next on my hit-list. This should net you the 145 - 150rwkw, and is the equivalent of Mania Stage 2, or FM's Big Enchilada.

After that ... you could upgrade the turbo, but you'd have to upgrade internals if you wanted make a decent jump, or you could get a flex sensor and tune for E85.

It all adds up. And it's probably worth at least considering buying a normal NB or NA, and turboing it. Get the good bits all at once, with a lower entry price.

[ManiacLachy]

Oh yeah, and read through several of the many SE builds in the Garage forum, plenty of inspiration there. Just don't be scared off by Lokiel's epic build

[davekmoore]

Oh yeah, and read through several of the many SE builds in the Garage forum, plenty of inspiration there. Just don't be scared off by Lokiel's epic build

or put off by my epic fails - brought about only by failing to look hard enough for one shop to do all the work and take responsibility for it all working correctly together.

[Nevyn72]

Lachy sums it up pretty well, everyone with an SE ends up going down the same path for a reason..... it works!
In short, there are 5 things you need to do to get a ~50% power increase on the factory car;
- Intake
- Exhaust
- Intercooler
- ECU
- Injectors

To this you add the following for reliabilty;
- Better BOV
- Improved boost control for higher boost, either electronic or manual

There are lots of other things you can do to the car but these are the ones for power improvements.

That being said, there is merit in the argument that you start with a base NB (cheaper) and do it from scratch. Although the SE does come with some other niceties from the factory you don't get on a standard car......

[Okibi]

All really great advice.

Intake and exhaust will let the engine breath better but you may start to have a boost cut around 5,500 rpm in 5th, so unless you're on the track it's not really as issue.

Some have also had a "bog" issue, which I think is blamed on a boost sensor near the drivers side strut top. I think a 3 way valve can fix this.

This is also solved if you upgrade the ECU, I have an adaptronic plug and play in my SE.

My SE engine mods are basically
Begi Intake > ebay Intercooler > FM up pipe and BOV > ID 725 injectors > cast pipe back 3" NitroDann exhaust > Adaptronic

I'm making 167.6HP at the wheels, not a massive improvement on paper but the car has more torque and is much more drivable.

To see how tiny the SE turbo is there's some pictures linked off here: http://www.mx5cartalk.com/SP_SE_Comparison/

[Okibi]

Also recommend putting one of these in the drain line from your catch can to the sump.

[ManiacLachy]

I should probably pick one of those up myself

[cookie]

It almost sounds like you'd be better off going down the nb + turbo kit vs se + upgrades. However how does this affect resale or insurance. Personally on an NA, my insurance barely changed when adding turbo addition. (Low powered t28 with ps1000, injectors, nitrodan manifold, fmic etc only cost me $1200)

Depends if you can find an se already upgraded, that'd be the most sensible option it'd seem.

[lizard]

The best way to devalue a good SE by $1000s is to spend $1000s on it

[ManiacLachy]

The best way to devalue a good SE by $1000s is to spend $1000s on it

That's true for any car. However the best way to get the SE to fulfill its potential is to spend a bit on it.

[Okibi]

The best way to devalue a good SE by $1000s is to spend $1000s on it

If cars are an investment then don't be a car enthusiast, be one of those guys who buys something like an MG and spends his life polishing it, trying to keep it "as original" and trailering it to car shows because it has 140,000 original miles.

If you like driving, buy an SE and modify it so it suits you.

[lizard]

The best way to devalue a good SE by $1000s is to spend $1000s on it

If cars are an investment then don't be a car enthusiast, be one of those guys who buys something like an MG and spends his life polishing it, trying to keep it "as original" and trailering it to car shows because it has 140,000 original miles.

If you like driving, buy an SE and modify it so it suits you.

[Dre]

It almost sounds like you'd be better off going down the nb + turbo kit vs se + upgrades. However how does this affect resale or insurance. Personally on an NA, my insurance barely changed when adding turbo addition. (Low powered t28 with ps1000, injectors, nitrodan manifold, fmic etc only cost me $1200)

Depends if you can find an se already upgraded, that'd be the most sensible option it'd seem.

Yes I was thinking the same.

I thought SE's came with 2560's until I read the replies here. So I would probably be upgrading almost everything on an SE anyway. Turbo + intercooler etc

I had a look on carsales.. I only like the post 2000 NB's styling but there are a few around the 10k mark with lowish k's. I think they've got the best rear end of all the models.

I have to remind myself that I was happy with the stock NC performance too so I might be chasing my tail. I'm going to line up a test drive in a fiesta ST before I act.

[smy0003]

You can find some already turboed nb2's. There's a black one for sale on here.
They are bargains because the average mx5 buyer won't touch them.