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I realise it is probably a stupid question but has anyone ever fitted or heard of someone fitting a supercharger to a NB8A automatic?

These cars have quite a tough 4 speed auto transmission with torque converter but I was wondering how they would stand up to another 40+ hp. and if other mods would be needed on transmission, suspension etc. as well.

My car is a 1999 model with 135,000km and the motor is in good nick using no oil or water etc.

I know the obvious answer is ditch the auto and buy an SE or something similar but I just thought I would get some ideas on feasibility/cost of this exercise.

xmx106 provided some info ref the NA auto transmission, which I believe carried over to the NB:
viewtopic.php?f=18&t=47371&p=594853&hilit=L4N71B#p594853

Hello,
I have an Eaton MP-62 Supercharger fitted to my 2002 Titanium manual. I understood the six speed standard gearbox is tough enough to cop the extra power ( running only 6 pounds boost ) so i would guess the standard auto would be up to the task. Might be worth a call to the MX5 factory to see if the experts know.
Cheers -

Thanks for reply. I have tried various MX5 dealers and the manufacturer. Unfortunately they wouldn't know a crankshaft from a mailbox and are only interested in selling new cars.

Sorry to hear you can't get any definite answer.The only other thought is to possibly post on an American or British site - a bigger market -
Best of luck,
Cheers -

Umm, okay...

Firstly, I don't know much about the automatics and there probably isn't a huge wealth of info on them as they were never all that popular on NAs and NBs. I would be very surprised if it couldn't handle an extra 40 hp though.

Secondly, how much research have you done on superchargers in general? They have a bit of popularity in the US but they're generally considered to be much more of a pain than a basic turbo setup for no real advantage. A simple turbo setup would get you the same level of responsiveness and comfortably the same power and torque characteristics with less hassles.

Finally, I don't know where you're located but your best bet to talk about aftermarket modifications is to talk to an MX5 specialist workshop, e.g. MX5 Mania in Sydney or MX5 Plus in QLD.

Yeah, thanks....I live near Wollongong NSW and I might give MX5 Mania a call. They probably have never done an NB auto but may have some advice.
I have been told the auto gearboxes are very strong but more recent enquiries have yielded other mods that may be needed with suspension, brakes etc. so it will probably prove too costly anyway for either turbo or supercharger conversion.

Probably finish up more economical to sell it and buy a good used SE or SP.

if its the same auto box as referred to earlier(jatco as used in vl rb30 engine'd commodore),these were tough as standard.
a regular party trick several of my friends would do from time to time in their vl's was.
1 select reverse
2 apply full throttle til approx 4500 rpm
3 select drive
4 apply full throttle
5 watch smoke from back tyres
6 do it again (or sometimes goto 1)
none of them blew up a box.although I wouldnt buy a used car off them,then or now!
Mick

You will have absolutely no problem adding 40hp to ANY car I can think of, Buy the bets bet would be to buy a turbo na6 manual.

Dann