Purchased a NC MX5 a while ago

Basic suspension mods done, BC coils and Whiteline sway bars 

New DBA calipers, discs and pads

Added some 17 x 8 Konig Decagrams with 215/45 17 PS5's

Added some typical NA bolt on's, i.e. full exhaust and intake 

Added 0.5ltrs with a MZR2.5 swap, nice bump in torques 

Found a detachable hard top which is locked in for a colour match with my local paint shop in Feb 25, this also includes some PDR as it has received a few love taps from parking in the local shops when in the hands of my Minister for War and Finances, me, I park nowhere near other cars and typically park on the street

The little thing is awesome, I drive it everywhere, it handles like a dream whether I'm up it or just cruising 

But now,  because I'm a idiot, I keep looking at turbo kits....... did I mention I'm a idiot

Why is dose so appealing 

All of the NA 2.5 glory, well.......until sometime in 2025 anyway....🤪

 

Hey that reminds me, are you changing your forum name to "The Hairdresser" too?

Or the cistransgender

40 minutes ago, Duncan said:

Hey that reminds me, are you changing your forum name to "The Hairdresser" too?

Nah, I think the current user name suits me pretty well

Turbo gods, some assistance and recommendations please

I'm looking into a turbo kit for my 2.5 from MX5 Mania >>>>> https://mx5mania.com.au/products/copy-of-mx-5-nc-2-5-litre-engine-conversion-turbo-2005-2013

Power wise I would like about 200kw atw, and of course dose noises, apparently if you keep a stock 2.5 under around 200kwatw the engine and drivetrain will not hate life even when ragging on it a bit

Max RPM on the 2.5 is around 6500rpm

The turbo MX5 use is something around the disco potato size as  packaging room for the turbo is pretty limited, which will, I believe, give me my power goals I want and not have the turbo either under, or oversized, but the rear housing bit is confusing 

It comes with either a 0.64 or 0.86

From my understanding, which so far is based off googling, so make of that what you will

0.64:

spools faster = good

Makes more EGT heat on boost = bad

Less topend power than 0.86 = I'm only looking for 200 atw so that point may be mute????, I don't know, hence my questions 

0.86:

Spools a "little" slower = how much slower??? remembering 6500 is my max rpm

Makes less EGT heat = good

Makes a little more power up top = again, power goals is only around 200

Also, this is a street car, so there will not really be any long track sessions, in saying this I would want it so it was happy with at least 3 hot laps at Wakefield Park if the need arises 

I already have a fancy pants triple pass radiator, and a oil cooler with thermostat will be getting installed as well

Thanks for any information or recommendations you have 👍, and of course, the comments about me wasting money on drive in drive out modifications, or any other snide remarks about my manhood for owning a MX5 🤣

 

 

This should be pretty easy.

200rwkW is just about the max power out of an RB25 stock turbo. So, 12ish psi on a 2.5L. That boost limited mainly by the prospect of seeing the turbine in the cat after the smoke show. A steel wheeled equivalent would likely happily do ~220rwkW at something like 17 psi, where it would probably be bumping into the usual limits of such a sized turbo.

These things have like a .48 rear.

You will not need the 0.86 rear. The 0.64 will be fine. In fact, if you were looking at various mid-200rwkW options for RBs, most of them would be in a 0.64 rear. So, I think you will definitely want to be no bigger than that for a same sized but probably even more efficient (at making power) modern engine.

Do you plan on using 98 or e85?

10 minutes ago, r32-25t said:

Do you plan on using 98 or e85?

98 mate

No detail on compressor or turbine sizes, which doesn't help with housing size selection with that kit.

However, from SR20DET mucking about and money torching perspective, a GTX2860R Gen 2 w/ 0.64 (46mm inducer) will do ~260kW on E85 about 1.5bar of boost. All in before 3000pm, which cause a gearbox to shatter.

Now imagine the same turbo, on a modern motor with an extra 0.5L of displacement, and heaps of cam timing adjustability (not an on/off affair like the Nissan shit boxes).

If this was my car (which I would never own or consider buying, ever!), I would go for a nice twin scroll setup, and a G30-660. Gates plumbed back, no silly shit. Lean on the cam timing, big displacement to create a flat-ish torque curve.

 

5 hours ago, The Bogan said:

Turbo gods, some assistance and recommendations please

I'm looking into a turbo kit for my 2.5 from MX5 Mania >>>>> https://mx5mania.com.au/products/copy-of-mx-5-nc-2-5-litre-engine-conversion-turbo-2005-2013

Power wise I would like about 200kw atw, and of course dose noises, apparently if you keep a stock 2.5 under around 200kwatw the engine and drivetrain will not hate life even when ragging on it a bit

Max RPM on the 2.5 is around 6500rpm

The turbo MX5 use is something around the disco potato size as  packaging room for the turbo is pretty limited, which will, I believe, give me my power goals I want and not have the turbo either under, or oversized, but the rear housing bit is confusing 

It comes with either a 0.64 or 0.86

From my understanding, which so far is based off googling, so make of that what you will

0.64:

spools faster = good

Makes more EGT heat on boost = bad

Less topend power than 0.86 = I'm only looking for 200 atw so that point may be mute????, I don't know, hence my questions 

0.86:

Spools a "little" slower = how much slower??? remembering 6500 is my max rpm

Makes less EGT heat = good

Makes a little more power up top = again, power goals is only around 200

Also, this is a street car, so there will not really be any long track sessions, in saying this I would want it so it was happy with at least 3 hot laps at Wakefield Park if the need arises 

I already have a fancy pants triple pass radiator, and a oil cooler with thermostat will be getting installed as well

Thanks for any information or recommendations you have 👍, and of course, the comments about me wasting money on drive in drive out modifications, or any other snide remarks about my manhood for owning a MX5 🤣

 

 

STOP GOOGLING

FAB9 MAKE BORG WARNER EFR KITS FOR THE NC. THEY PACKAGE AN EFR 6758.

DO NOTHING ELSE. CAPS INTENTIONAL. THE BEST RESPONSIVE SETUP EXISTS FOR YOUR CAR, AND HAS BEEN PROVEN FOR QUITE SOME TIME NOW.

IN B4 "BUT I WANT EVEN MORE RESPONSE, IN A SIMPLER, MORE RELIABLE PACKAGE" WHICH IS A LS.

2 minutes ago, Kinkstaah said:

STOP GOOGLING

FAB9 MAKE BORG WARNER EFR KITS FOR THE NC. THEY PACKAGE AN EFR 6758.

DO NOTHING ELSE. CAPS INTENTIONAL. THE BEST RESPONSIVE SETUP EXISTS FOR YOUR CAR, AND HAS BEEN PROVEN FOR QUITE SOME TIME NOW.

IN B4 "BUT I WANT EVEN MORE RESPONSE, IN A SIMPLER, MORE RELIABLE PACKAGE" WHICH IS A LS.

I somehow quoted my post instead of editing it. I regret nothing.

This came quicker than I thought. It ain't even 2025 yet.

I know you don't want to hear this comment, but I can't not say it. 

I just can't see 200kw being worth the time and effort. Its like guys with NA cars, putting in headers/exhaust/tune for a massive 20% jump in power. Great, the slow car is still slow and you're down $10,000. 

My vote is leave it NA or price in a gearbox upgrade and shoot for at least 300KW, preferably 350KW+. 

Now you have a NC that will try to kill you from time to time and will be exciting to drive

6 hours ago, Murray_Calavera said:

I know you don't want to hear this comment, but I can't not say it. 

I just can't see 200kw being worth the time and effort. Its like guys with NA cars, putting in headers/exhaust/tune for a massive 20% jump in power. Great, the slow car is still slow and you're down $10,000. 

My vote is leave it NA or price in a gearbox upgrade and shoot for at least 300KW, preferably 350KW+. 

Now you have a NC that will try to kill you from time to time and will be exciting to drive

This isn't for lotsa powers, and time and effort isn't even a thing I'm concerned about

The whole reason is "Just because fun", and "Just because fun" is what I do

And whilst there are other kits, with better and more modern turbos (Rev9 use the same Kraken manifold I believe), where in Sydney can I do a drive in drive out with the after sales support that MX5 Mania give

My Turbo 86 made around 200kwatw on a AVO turbo kit, and was over 100kg heavier than the MX5, but it was a blast to drive around the streets, until I crashed it.....DOOH, so somewhere around 200 ish level and some whooshy noises and I'll be happy driving to work, the shops, or heading into the country with Jackie for Devonshire tea

So, thanks Dose for your info, it sounds like a 0.64 will be fine for what I'm after👍

The only real racing I do nowadays is to the toilet

 

8 hours ago, Kinkstaah said:

STOP GOOGLING

FAB9 MAKE BORG WARNER EFR KITS FOR THE NC. THEY PACKAGE AN EFR 6758.

DO NOTHING ELSE. CAPS INTENTIONAL. THE BEST RESPONSIVE SETUP EXISTS FOR YOUR CAR, AND HAS BEEN PROVEN FOR QUITE SOME TIME NOW.

IN B4 "BUT I WANT EVEN MORE RESPONSE, IN A SIMPLER, MORE RELIABLE PACKAGE" WHICH IS A LS.

 

11 hours ago, Dose Pipe Sutututu said:

No detail on compressor or turbine sizes, which doesn't help with housing size selection with that kit.

However, from SR20DET mucking about and money torching perspective, a GTX2860R Gen 2 w/ 0.64 (46mm inducer) will do ~260kW on E85 about 1.5bar of boost. All in before 3000pm, which cause a gearbox to shatter.

Now imagine the same turbo, on a modern motor with an extra 0.5L of displacement, and heaps of cam timing adjustability (not an on/off affair like the Nissan shit boxes).

If this was my car (which I would never own or consider buying, ever!), I would go for a nice twin scroll setup, and a G30-660. Gates plumbed back, no silly shit. Lean on the cam timing, big displacement to create a flat-ish torque curve.

 

 

 

 

7 hours ago, Murray_Calavera said:

I know you don't want to hear this comment, but I can't not say it. 

I just can't see 200kw being worth the time and effort. Its like guys with NA cars, putting in headers/exhaust/tune for a massive 20% jump in power. Great, the slow car is still slow and you're down $10,000. 

My vote is leave it NA or price in a gearbox upgrade and shoot for at least 300KW, preferably 350KW+. 

Now you have a NC that will try to kill you from time to time and will be exciting to drive

This isn't for lotsa powers, and time and effort isn't even a thing I'm concerned about

The whole reason is "Just because fun", and "Just because fun" is what I do

And whilst there are other kits, with better and more modern turbos (Rev9 use the same Kraken manifold I believe.....EDIT... nope, the Kraken is a cast jobbie, the REv9 uses welded up stainless, plus $8000 AUD before shipping, installation and tuning)

Where else in Sydney can I do a drive in drive out with the after sales support that MX5 Mania give

My Turbo 86 made around 200kwatw on a AVO turbo kit that Pulse fitted, and it was over 100kg heavier than the MX5, but it was a blast to drive around the streets, until I crashed it.....DOOH, so somewhere around 200 ish level and some whooshy noises and I'll be happy driving to work, the shops, or heading into the country with Jackie for Devonshire tea

So, thanks Dose for your info, it sounds like a 0.64 will be fine for what I'm after👍

The only real racing I do nowadays is to the toilet

11 hours ago, Dose Pipe Sutututu said:

No detail on compressor or turbine sizes, which doesn't help with housing size selection with that kit.

PULSAR PSR2860R 0.86A/R or 0.64 GEN 2 Turbocharger

Both are -50*67mm 8 blade billet compressor wheel

Cheers

 

I’d go the smaller rear just because you’re staying on 98, if e85 I’d go the bigger one

47 minutes ago, The Bogan said:

PULSAR PSR2860R 0.86A/R or 0.64 GEN 2 Turbocharger

Both are -50*67mm 8 blade billet compressor wheel

Cheers

 

What kind of power delivery are you after?

If it's nice and linear, the 0.86 would be better. If you're after bake tyres and head snaps on boost the 0.64 would be fun.

I'm boring and old, so linear power is preferred.

Lately I've been watching videos on Z06 Corvettes and super charged Mustangs.... 

11 minutes ago, Dose Pipe Sutututu said:

What kind of power delivery are you after?

If it's nice and linear, the 0.86 would be better. If you're after bake tyres and head snaps on boost the 0.64 would be fun.

I'm boring and old, so linear power is preferred.

Lately I've been watching videos on Z06 Corvettes and super charged Mustangs.... 

Cheers for the info mate, I'm old too, 60 years old next May, so a more linear delivery of the 0.86 would be better as baking tyres and snapping heads isn't on the cards for me or the car

I assume a more linear power delivery would be better for engine and drivetrain reliability as well, IRT the torque load at lower RPM???, as well as lower EGT's???, if my understanding of that is correct, have I got that right???

I've only got a really basic understanding of turbo sizing and all there characteristics 

Cheers for the useful information 

19 minutes ago, The Bogan said:

Cheers for the info mate, I'm old too, 60 years old next May, so a more linear delivery of the 0.86 would be better as baking tyres and snapping heads isn't on the cards for me or the car

I assume a more linear power delivery would be better for engine and drivetrain reliability as well, IRT the torque load at lower RPM???, as well as lower EGT's???, if my understanding of that is correct, have I got that right???

I've only got a really basic understanding of turbo sizing and all there characteristics 

Cheers for the useful information 

Nah nah nah nah. Don't do it.

It's not all about the full throttle power delivery. The main "street fun" and drivability gains from smaller rear (in this case) is how you will have boost available from a low rpm when yo just roll onto the throttle. Think jinking in and out of traffic, coming out of roundabouts, etc etc, where you just want to roll onto the throttle a little and have the spooly noise from ~2000rpm and a swell of torque. More of what you've already achieved by going to 2.5.

And then, towards the tail end of 2025 you can pull the turbo 4 out and put in a V8 like we originally suggested. :P