Looking for naturally aspirated guide

tescoking · Postby **tescoking** » Fri Mar 15, 2013 8:00 am

Hi guys, I have a Mx5 NB 2001 planning to go N/A instead of turbo, because I really cannot afford that much money and I would love to drive my Mx5 for the next 10 years, I know N/A will keep my engine last longer. At the moment I have installed the K&N cold air intake and I am planning to replace the ignition leads and spark plugs with higher quality, after that I don't know what should I change, can anyone give me some ideas? This is my first time in my whole life to modify a car, please give me as muc as info as you can, even small little things like radiator, fan, tire, anything that you think is good to have to improve the performance of my car. By the way, I am not using the car for track race, drag race, or AutoX, but sometimes I would like to go a bit over on the street when there are no one, please let me know your idea of how to build a fast Mx5 on the street. Thank you.

spikes · Postby **spikes** » Fri Mar 15, 2013 8:42 am

What sort of power goals are you after. A proper NA build will be way more expensive than a turbo.

Can get some decent gains with a full exhaust, extractors, cams and an ECU. But for that money you'd be able to put together a turbo kit and pump 200HP easy. More HP per dollar spent

An all out NA build with 200HP won't last as long as a turbo 200HP motor

project.r.racing · Postby **project.r.racing** » Fri Mar 15, 2013 10:19 am

some ecu friendly camshafts is probably you next step. after that, the money will start to fly out your wallet.

Postby **NitroDann** » Fri Mar 15, 2013 11:29 am

A turbo build will be cheaper to build, cheaper to maintain,and your engine will last much longer with less maintenance.

Dann

sailaholic · Postby **sailaholic** » Fri Mar 15, 2013 11:47 am

I agree after basic exhaust intake and ecu friendly cams, your beyond the point of no return. Turbo or na, won't matter dollars wise, but turbo power will be better.

Sent from my GT-I9100 using Tapatalk 2

spikes · Postby **spikes** » Fri Mar 15, 2013 12:13 pm

an ECU with cams would be beneficial for turbo later down the track when OP can afford a turbo or bigger mods.

Postby **NitroDann** » Fri Mar 15, 2013 12:49 pm

But the cams and install buy half a turbo setup.

Either way it represents bad value.

Dann

manga_blue · Postby **manga_blue** » Fri Mar 15, 2013 1:02 pm

2001 says it's an NB8B doesn't it? So it's a VVT engine. The choice of cams is a bit limited to Tomei/Maruha Poncams at around $1,300 inc postage ( http://page12.auctions.yahoo.co.jp/jp/a ... p331610768 ) and they're very mild.

In reality with an NB8B you can put in a full exhaust and cold air intake to give a 10% increase in power and a much nicer running car. After that you only have a series of small incremental increments from cams, headwork, high comp pistons and rods, bigger headwork, etc. Gains from a better ECU are only pretty small because the NB8B ECU wasn't that bad.

The choices for a VVT come down to either a slightly sweeter car with a good exhaust or a turbo and a lot more power,

Postby **NitroDann** » Fri Mar 15, 2013 1:59 pm

Gains from cams get you 50% at least over stock, but no one makes big enough VVT cams to do this.

Dann

M1474 · Postby **M1474** » Fri Mar 15, 2013 2:14 pm

Make sure your dampers are good

Get a good wheel alignment

Buy the lightest 15" wheels you can find and fit the best tyres you can afford.

wozzah1975 · Postby **wozzah1975** » Fri Mar 15, 2013 5:42 pm

spikes wrote:An all out NA build with 200HP won't last as long as a turbo 200HP motor

In what way??

Woz

mazmad · Postby **mazmad** » Fri Mar 15, 2013 6:26 pm

Why would he want 200bhp for the street? Enough traffic light heros around already.

Intake and exhaust, maybe coilovers if you want to improve handling, and you have a real fun car. Responsive and crisp handling.

manga_blue · Postby **manga_blue** » Fri Mar 15, 2013 6:50 pm

The truth is that the NB8B head is not the modifier's preferred route. A simpler way could be to get someone like Wozzah to prepare a second NA8 or NB8A head and intakes for you while you source a matching exhaust and ECU. Head can be built anywhere from warm to stonking hot and the whole lot can be swapped in in a day, including a dyno tune. You can keep the original head and other bits so you can return it to stock anytime you like.

wozzah1975 · Postby **wozzah1975** » Fri Mar 15, 2013 8:17 pm

tescoking wrote:Hi guys, I have a Mx5 NB 2001 planning to go N/A instead of turbo, because I really cannot afford that much money and I would love to drive my Mx5 for the next 10 years, I know N/A will keep my engine last longer. At the moment I have installed the K&N cold air intake and I am planning to replace the ignition leads and spark plugs with higher quality, after that I don't know what should I change, can anyone give me some ideas? This is my first time in my whole life to modify a car, please give me as muc as info as you can, even small little things like radiator, fan, tire, anything that you think is good to have to improve the performance of my car. By the way, I am not using the car for track race, drag race, or AutoX, but sometimes I would like to go a bit over on the street when there are no one, please let me know your idea of how to build a fast Mx5 on the street. Thank you.

Ok,

IMO
Don't waste your money on fancy spark plugs. Power wise there is absolutely no difference between a std v groove NGK at around $5-6 when compared to a $25 platinum or Iridium plug. I am not a fan of long life plugs, apart from being expensive, they don't last anywhere near as long as advertised, are 99% responsible for premature coil pack and ignition failure, and because they're in there so long are prone to seizing in their and creating more headaches. Just use an NGK v groove.

In regard to leads, the same applies. Any decent quality 8mm stainless core lead will be fine. Don't be fooled into thinking you have to run big fancy 10mm leads, you don't. A very good friend owns and manufactures Hurricane Ignition leads, these are IMO the best bang for buck you will find. http://www.hurricaneautomotive.com.au/h ... leads-home
If you have trouble getting them PM me, but you should be able to organise a set. Once again, a very small increase if any from OE items in good condition.

At the moment I think the next stage of your mods should be decent 4-2-1 extractors and a sensible exhaust system.

Keep this in mind. Doing mods to NA applications requires TLC as to not go backwards in power, and generally the mods you do only give small increases in power until you start getting serious with cylinder head, cams, ECU etc. It's pretty straight forward for a 15-20kw increase in power from stock, but after that it gets alot harder and much more expensive no matter what route you decide to take. If you're expecting to bolt on a few goodies and have an extra bucket load of power it's not going to happen without spending decent amounts of money and/or turboing it.

Probably what you need to ask yourself is how much you're prepared to spend, and what power you would be happy with.

Cheers
Woz

tescoking · Postby **tescoking** » Fri Mar 15, 2013 8:25 pm

Actually I am not so sure my car have the VVT engine or not, can I tell from the spark plugs? I only have two compare with the previous version.

I really don't have patient to save up to $10000 for turbo, I love N/A is because its allow me to change parts bit by bit, I am not trying to do a engine swrap until the engine die, so at the moment I have a K&N cold air intake, what else can I change for next step? Can someone provide a detailed guide please? I really love the way that changing the car little by little and knowing my car:)