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Holidays in December, I am away for 2 weeks.

Want to wind up the boost on my car to achieve around 200kw atw.

Currently, Garrett T28 turbo, built up clutch 1400 lb pressure plate, PWR radiator, coolant bypass reroute, 440cc injectors, after market fuel pump.

Currently, 168.2kw atw at 12 psi.

After recommendations for building up engine and costs for achieving 200 mark.

Any help appreciated.
Cheers Novice1

I'm only a newbie but from what I've read so far you'll need stronger (and possibly lower comp) pistons and stronger rods, but the crank may be ok as is.

I'll be watching for responses from those who know more than me for when I put the high flow turbo on mine.

Turn the boost up to 18psi or so. You'll make 200 at the wheels, once...

From the reading that I've been doing, www.miataturbo.net has a bunch of people who really know their stuff. If you're looking to expand your knowledge, it's a great place to start. The only problem is it's a brutal place, so if you ask a dopey question they'll let you have it!

As far as I'm aware, you'll mainly want to do pistons and rods. I've never heard of anyone changing (or needing to change) the crank for that kind of power. I have no idea as far as cost is concerned, forced induction is waaaay out of my budget atm so I never bothered looking

One thing to note, if I remember rightly the 5 speed transmission starts getting fragile at around the 250 HP mark (186kW), so if you don't treat it nicely it might just go to pieces on you.

Of course, I've never dríven or owned a turbocharged MX5, so take everything I said with a grain of salt!

[quote="Kain"]From the reading that I've been doing, http://www.miataturbo.net has a bunch of people who really know their stuff. If you're looking to expand your knowledge, it's a great place to start. The only problem is it's a brutal place, so if you ask a dopey question they'll let you have it!

As far as I'm aware, you'll mainly want to do pistons and rods. I've never heard of anyone changing (or needing to change) the crank for that kind of power. I have no idea as far as cost is concerned, forced induction is waaaay out of my budget atm so I never bothered looking

One thing to note, if I remember rightly the 5 speed transmission starts getting fragile at around the 250 HP mark (186kW), so if you don't treat it nicely it might just go to pieces on you.

I, was sort of hoping that changing the transmission might not be a necessity, but realistically its probably the next weakest link in the chain. Having to change to transmission may make the project beyond my budget. Realistically, though the transmission is probably the next weakest link.

Thanks for the input guys.
Cheers
Novice1

MX52NV where art thou?
440cc may JUST cut it, but I think it's stretching its safe 80% duty cycle.
If you're gonna do it, go for at least 550cc.

168kW@wheels is a very good figure for "just" 12psi IMHO.
Take it to a lofty "BS Performance" dyno and you'll get your 200kW figure without doing any mods

wanna sell the 440's then? :p

440's will be enough if you have a higher pressure fuel pump and a good rising rate regulator. hp won't kill your transmission. torque and your driving style will. but if you are making 200wkw then you will be making well over 400nm so will probs need a 6 speed. just drive it nicely until it breaks or you can find a good priced box.

440's will be enough if you have a higher pressure fuel pump and a good rising rate regulator. hp won't kill your transmission. torque and your driving style will. but if you are making 200wkw then you will be making well over 400nm so will probs need a 6 speed. just drive it nicely until it breaks or you can find a good priced box.

Head studs, main studs, good rods and the best rod bolts you can buy. Double valve springs would be a good thing. Conversion to a returning fuel rail with surge tank and decent pump (bosch 044) would be advisable with a decent 1:1 FPR. I would suspect 550ccs would be a minimum too - I use 580ccs. Gearbox will not last long - at 190rwkw, the teeth start to strip off the gears -the 5sp is crap, the standard 6 is better, the SE one is best, brakes might need a tweak too - stopping is handy. You will also start to trouble the driveshafts at that power level - lucky for you we already have had billet ones made.

16bit wrote:440's will be enough if you have a higher pressure fuel pump and a good rising rate regulator. hp won't kill your transmission. torque and your driving style will. but if you are making 200wkw then you will be making well over 400nm so will probs need a 6 speed. just drive it nicely until it breaks or you can find a good priced box.

Can't remembre whether they were 440, 450 or 550 injectors, will have to check my invoices.

Fuel pump is aftermarket walbro, but no rising regulator.

Torque figure is 370-380 NM at 5250rpm, on 12 psi

Retune as soon as a few tidy up jobs done on the car. Boost up to 12.5psi. If, it breaks, it breaks.
Will also be on the lookout for some 15'' inch lightweight rims and tyres, just for track days.
Cheers Novice1

I happen to have BEGI RFPR sitting in a box here - wanna look and make an offer?

Got to also say - I always found the guys over at miataturbo to be an amazingly helpful bunch.

Uncle Arthur wrote:I happen to have BEGI RFPR sitting in a box here - wanna look and make an offer?

Got to also say - I always found the guys over at miataturbo to be an amazingly helpful bunch.

Car back from retune. Tuner doesn't believe I need a RFPR.
Cheers Novice1

Why set a target of 200kw? (or any number)

200kw is easier on some dynos than it is on others if you get my thought process...

Sean wrote:Why set a target of 200kw? (or any number)

200kw is easier on some dynos than it is on others if you get my thought process...

In the mountains big power figures can be more difficult to deal with.

I, am happy with what I have got now.

Cheers Novice1