To Build or To Buy? Advice Appreciated

[Skifey]

Hey guys!

Long time lurker, recently joined and first time poster on here. You guys are awesome by the way
So I'm in the market for an NA mx-5. I have a budget of around 4-6k for the purchase of the car alone and a maximum budget of around 10-12 over the duration of the project.

Here's my plan and below that you'll find my question;
I ride bikes so I'm used to impressive performance. Everyone reckons that the ONLY complaint they ever have, if any, with the MX-5 is power. I want to grab an NA series, because the NB look just bothers me for some reason (and there'll be no convincing me otherwise)
Now because it's going to be near impossible for me to pick up a 1.8L NA for the price I'm looking at I want to simply buy an earlier model NA 1.6L and drive it around until I get bored of it, at least appreciate the original car for awhile, then I want to pull the 1.6L, swap it for a 1.8L and add on a small-modest sized turbocharger. From what I've heard, read and seen it doesn't seem to be a terribly uncommon or difficult modification and I plan on doing most if not all the work myself, despite having little to no mechanical experience whatsoever. I am damn good with my hands though and I'm no egghead.
I figured by doing the engine swap I can pay less than I would (total) then I would if I were to buy a standard 1.8L NA. I'm hoping I can pick it up a decent amount of time prior to actually doing the swap and while its out of the car, breathe as much new life into as possible from a bang-for-buck standpoint. I.e all standard servicing, new injectors yada yada yada.

I am aware of;
It would be less expensive to simply buy an NB with a 1.8l already in it
The necessary additional modifications needed to turbocharge an mx5 (radiator, coil packs etc)


My questions;
Firstly: is it a dumb plan from an experience point of view and a price point of view?
Secondly: is it even doable/viable to do it this way.
Thirdly: any advice with doing it this way
fourthly: what sort of money should I be realistically budgeting for such a project. I am by no means 'rich'
fifthly; am I just a complete idiot with no idea what he's doing?

[smy0003]

Turbo gets expensive very quickly. Clutch, ECU, cooling, intercooler piping, tuning etc. Will easily blow out to $7k+ and that's before you buy a 1.8l. Engineering charges will be more money again.
A 1.6 Will need a brake and diff upgrade as well, making a 1.8l base the more financially sensible option.
If you have limited mechanical experience you'll need money to pay someone when you get stuck. A thorough understanding of how an engine and turbocharger work is required if you're going to source your own parts properly.

Where are you located?

Sent from my LG-H815

[pepejesus]

My questions;
Firstly: is it a dumb plan from an experience point of view and a price point of view?

Yes

Secondly: is it even doable/viable to do it this way.

Doable

Thirdly: any advice with doing it this way

Don't

fourthly: what sort of money should I be realistically budgeting for such a project. I am by no means 'rich'

Double whatever you're thinking

The NA6 is inferior to the NA8 in every possible way. Smaller brakes, weak (like they are known to break at stock power levels) diff, short nose crank problems in earlier cars, etc. The difference between the two is much more than just 200cc.

If you want the true original MX5 and are happy to keep it stock-ish then the NA6 can be a really good buy.

If you want to turbo it, the NA6 is easily the worst option. You'll end up replacing everything and it will cost you a hell of a lot more in both time and money.

To go turbo, starting with an NB8B is probably the most sensible option as you'll get the 1.8, 6-speed box, decent diff, big brakes, chassis bracing, etc.

But if you're dead set against an NB then starting with an NA8 would be a far better proposition, as far as bang for your buck goes.

Starting with an NA6 because you 'can't afford' an NA8 yet plan to spend 10-12k on it makes no sense to me at all. Just spend more on the original purchase and less on the modifications.

[Skifey]

Where are you located?

Sent from my LG-H815

Brisbane, western suburbs

[Skifey]

The NA6 is inferior to the NA8 in every possible way. Smaller brakes, weak (like they are known to break at stock power levels) diff, short nose crank problems in earlier cars, etc. The difference between the two is much more than just 200cc.

If you want to turbo it, the NA6 is easily the worst option. You'll end up replacing everything and it will cost you a hell of a lot more in both time and money.

To go turbo, starting with an NB8B is probably the most sensible option as you'll get the 1.8, 6-speed box, decent diff, big brakes, chassis bracing, etc.

But if you're dead set against an NB then starting with an NA8 would be a far better proposition, as far as bang for your buck goes.

Starting with an NA6 because you 'can't afford' an NA8 yet plan to spend 10-12k on it makes no sense to me at all. Just spend more on the original purchase and less on the modifications.

Fair enough, I never thought turbocharging it would wind up cost 7k+, I was thinking more like 4k max given that I was going to source cheap second bits and bobs from gumtree etc

[NitroDann]

Absolutely no chance in the world man. You will pay a shop 800+ just to tune it assuming you can build an entire turbo car with no experience for the other 3200.

The cheapest ecu/injectors/boost control etc that an amateur can just clip in and get running at home is 2000.

Dann

[ManiacLachy]

I like the plan, if I had my time again I think I'd want a turbo 1.8 VVT NA. However, the costs will range from much more than you think to SO VERY much more than you think, depending on your mechanical aptitude.

Maybe get the NA drive for a while and see if you even like it, or hang around waiting for a turbo NA to come up for sale while saving your money.

[Skifey]

The cheapest ecu/injectors/boost control etc that an amateur can just clip in and get running at home is 2000.

Dann

Seriously? That much? I thought you could pick up rx8 injectors from the wreckers for next to nothing or go onto ebay
In the name of research I've got and dug some prices

- Found rx8 injectors on ebay for $135
(http://www.ebay.com/itm/GENUINE-OEM-Maz ... u8&vxp=mtr)
- Found a megasquirt ECU for $799 (assumedly USD) so around 1k AUD
(http://949racing.com/megasquirt-miata.aspx)
- Cannot find a boost solenoid for the life of me, does anyone know where to source them from?

That aside, (and please dont get me wrong - I'm not trying to say "i'm right your wrong" I just want to confirm) am I looking at the correct parts here or am I missing something. Understandably prices for these things would fluctuate, so realistically, is it really going to cost me 2k minimum for those parts you listed?

I should also note: I was a bit tough on myself when I said I had little to no experience - I do have experience doing basic stuff i.e. engine removals, servicing, basic upgrades like exhaust, headlights, coil sets, spark plugs, gaskets etc. I just dont think at all that I'm able to call myself 'experienced'

Thanks for all the feedback so far guys. Really appreciate it.

[smy0003]

I have been through the process of turbocharging an na8.
A megasquirt may be 799 in the states in USD but gst, shipping and duties push it up to $1.5kAUD. A mspnppro will be $2k by itself.
Listen to Dann. He turbocharges mx5s daily for a living.

Sent from my LG-H815

[NitroDann]

I'm building one now. Literally.

Add shipping and gst, couple hundred for injectors, what will you use for a TPS? And wideband, couple hundred more. Mac Valve, another 90.

[manga_blue]

Another way to look at this is to recognise that the stock NA6 is still one of the best driver's cars around, even with the low power.

So you culd buy one and just drive it stock for a while. If you want a bit more you can just free up the motor a bit with bolt-ons - a good exhaust, cold air intake, Megasquirt ECU - to give you an extra 15-20rwkw at a much better spread. You could do that with quality bits for under $2.5k and not worry about legality or other driveline mods apart from making sure all the fluids, cooling system and pads are in good shape and good quality. Drive that for a year or two and if that's not enough you can buy another motor and build it as a background project - cams, porting, maybe internals, etc - but then you wuld have to factor in brakes, diff, cooling, ...

[Skifey]

Listen to Dann. He turbocharges mx5s daily for a living.

:O What manner of god are you Dan?
In all seriousness though, lets say I manage to pick up a 1.8L NA for 6k. Assuming that nothing is wrong with it (speaking theoretics here) and all is well and nothing goes awry. What is going to come out of my wallet (roughly) by the time that little NA is sitting in my garage, running on low-medium boost comfortably tuned and living life healthily as a turbo mx5? And this is assuming I'm dam well smart about sourcing parts, and doing everything within my power as an amatuer engine tinkerer to reduce costs.

Sorry for the questions; it just seems like I'm in over my head and I'm just wanting to confirm that suspicion

[93_Clubman]

Yeah, get a cheap standard NA6 to see if you like it. If you do, then concurrently look out for a turbo'd NA. Turbo'd NA6s come up for sale reasonably regularly - turbo'd NA8s less so.
You've thought about what you'd like to achieve & how you might do it, & we appreciate it's about the journey & the destination, but in the nicest possible way, let someone else take the hit unless budget isn't so much of an issue.

[smy0003]

I purchased an na8 for $6k. It was very healthy with low kilometers. I spent two years researching and buying parts from nissan, rx8, Suzuki and Mitsubishi forums. All in I would've spent over $15k, and I got everything at an absolute steal. The ECU, the wideband and the manifold/dump I got for next to nothing and it still blew your budget.

Sent from my LG-H815

[StanTheMan]

NA8 is a better base. Believe me I've owned a NA6 for 20 years.....almost

for you it seems all about straight line speed & the acceleration?

You can beat most motorbikes around the twisters with 100 HP good suspension set up, good tyres , Torsen or LSD of your choice & good brake pads.

You have to be a bit of a nutter though. And if the motorbike still beats you. That rider must be totally insane.

Having power makes me (personally) lazy in shifting.
Having power is great for the racetrack
Having power is awesome for overtaking on country roads.
You don't need power for impressive performance

My 02