16bit

hey guys I am new on the forum. I have a 1998 nb mx5 with a rotrex supercharger. Its on about 9.5 psi and makes around 220hp at the wheels. The motor I have at the moment has a 9.5 compression ratio as it is standard. I am thinking of building a 10 compression motor with forged internals and running about 10psi through it. Will a 10 compression motor be able to safely handle 10psi providing its tuned properly? thanks guys.

patsmx5

iTrader: (16)

Sure. I'd run more boost and less compression myself. You can take the heat out of the boost.

Saml01

iTrader: (9)

Woh, a roterx? Post pictors now.

16bit

i will take some pics tonight and post them.

Braineack

iTrader: (62)

iirc, y8s is making 260rwhp on his 10:1 motor at 9.5psi.....

y8s

iTrader: (8)

we need a sticky about how boost is irrelevant.

I'd say you're safe up to 250 rwhp if you have an INTERCOOLER.

otherwise, call it 225 before the intake temps are too hot to be safe. *shrug*

cardriverx

iTrader: (12)

pics! pics pics pics!!!

RotorNutFD3S

iTrader: (33)

A 1998? I'm guessing a '99 released in '98 then?

miatamania

iTrader: (9)

Overseas they released early I think

in both a 1.6 and a 1.8 IIRC?

I could be wrong, its late, I'm tired, and I don't really care to find the real answer.

16bit

yeah its an australian car so a 98 nb. 260whp sounds great. What sort of head work do you guys recommend for supercharged cars?

emilio700

iTrader: (3)

Yes.

I use an '03 10:1 bottom end and a tiny GT2554R running 10psi. IATs are good with an 11x11x3" FMIC. Your Rotrex puts more heat into the intake charge but the fuel you have over there has better detonation resistance.

A knock sensor and EGT with proper monitoring/management are a good idea.

Ben

iTrader: (33)

No reason why you can't, as long as your engine management and tuning ability are up for the task.

16bit

my rotrex would put a lot less heat into the intake then a turbo - it does have a fmic too. and the 5th injector is just before the throttle body so that would take out whatever heat that the intercooler didn't

here is an old pic of the engine bay but its pretty much the setup:

zoom2zoom

iTrader: (5)

that is just beautiful!!

zoom2zoom

iTrader: (5)

And have you ever lined up with a new GTO for a quick race?

16bit

nope I have not really raced anything. I do a bit of mountain driving and it seems to be pretty sharp around the corners.

mike_671

iTrader: (4)

that thing looks sick

cardriverx

iTrader: (12)

is that the first rotrex miata?

Braineack

iTrader: (62)

there's a few across the pond.

Doppelgänger

iTrader: (12)

im running 10-11psi on a stock 2002 Motor with no problems. Tuning has a lot to do with how much power you can make on a given motor. For a "built" 10:1 comp. motor you should be able to make more then enough power.

BTW, its nice to know that JR wasn't blowing smoke with showing those kits. Im really curious as to what they're going to get out of them.