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if you limit yourself to about 12psi you won't have to do any work to the internals.

i'll let someone else explain what needs to be done if you decide to go to 15psi.

i dunno, for an extra 3 psi it just doesn't seem like it's worth the extra time and money (lots of it) to me.

all the info i have read says yes, you can as long as you don't thrash the f**k out of the car.
haven't done it myself yet tho.

At about 15PSI you will start to blow things up.

Sabretooth is doing a massive thread in this section of the forum about his rebuild. He wants to run serious boost - 15+PSI. Guys like Sean, Sabretooth, MX5_DriftFury, Sheck and a few others are running quite high boost, some did rebuilds, some didn't... They are the kind of guys you need to spot this thread and answer a few of the more technical questions... However, several guys run turbos at lower than 15PSI and can lend a hand anywhere else you need.

Boags

The stock injectors are not even good for 5psi at stock pressure. They can be made to fuel 8psi with high pressure.

The stock fuel pump with big enough injectors will be good for up to 10psi.

So add both of those to your list. I think the 190l/h is what most of the guys use. And 330cc GTX, 305cc Supra or bigger - RX7 440cc injectors are all plug and play.

And yes, you would need a piggyback/standalone.

Boags

ant, check your private messages. i sent you a link to a whole bunch of info that should answer lots of your questions.

you will also most likely need to upgrade your clutch, diff, and brakes.

Fatty wrote:i'll let someone else explain what needs to be done if you decide to go to 15psi.

On the size of turbo you're going to run i don't think you'll have problems at 15psi.

I've run a lot more on stock engines for limited periods, and can constantly run 17-18psi in a stock engine with no prblems over 40,000kays on a second hand engine that nalready had about 100,000 kays on it.

Just make sure the car is tuned right and 15psi won't be a worry.

ALso remeber that 15psi is the upper limit (if you choose 15psi). In city driving to work etc, in traffic, you'll be lucky to see double digit boost figures anyway.


SO engine itself is fine at 15psi - but i'd change clutch probably diff and make sure your cooling system is up to speed and functioning perfectly too.

davie_baby16 wrote:ANNNNNNNND you can chuck 30psi somewhat safely if
u like high psi!!!!!!!!!!!

Hmm, not in a stock one....
Not if you like reliability....


You'd need considerable dowling at the very least.

davie_baby16 wrote:Just go 13b turbo hell yeah thats the way im going!!!!!!!!

No valves to drop, no circular pistons to worry about, no modifing of engine internals!!!!!!!!!!!!!!!

BRAP BRAP!!!!!!!!!!!!

Just lotsa apex seals to sh*t into the very spendy turbocharger.

davie_baby16 wrote:Just go 13b turbo hell yeah thats the way im going!!!!!!!!

No valves to drop, no circular pistons to worry about, no modifing of engine internals!!!!!!!!!!!!!!!

BRAP BRAP!!!!!!!!!!!!

thats sorta what im doing, i've saved over half the money i need for a 20btt

im running a VF10 turbo and its a fantastic turbo for the mx5.It gets to 7 psi at exactly 3000 rpm and holds all the way to redline. Ive dyno'd it at over 140RWKW at nearly 8 psi boost. The boost level you can run will be limited my the engine management you have....id stay under 10 psi if your using a piggy back or rising rate fuel pressure regulator over 10 psi you need a good stand alone ECU and over 12-13 psi your gonna need a good supply of diffs and gearboxes.
have a look:

http://www.cardomain.com/ride/264041/6

Why is everyone here so against rotaries?
Get a decent built block and you will have sooo much fun,
Id Know!
And you'd rip most turbo cars a new bunghole with such simple mods!
brap brap

Duj wrote:Why is everyone here so against rotaries?
Get a decent built block and you will have sooo much fun,
Id Know!
And you'd rip most turbo cars a new bunghole with such simple mods!
brap brap

Simple mods?

No.

The ability to rip a new bunghole - in most cases - hell yes.

Why are most people against them? $$$$$$$$$$$ Try a full $4000 rebuild every 30-100K depending on how you treat it. Not to mention the cost of conversion.

I love rotaries, my mate has an RX4 and a Datto 1600 with a 13B Bridgeport, but he is broke. Always.

Boags

Boags'MX5 wrote:Try a full $4000 rebuild every 30-100K depending on how you treat it

Full seal kit and 2 new rotor housings are around 4K just in parts...and you'd wanna hope your eccentric shaft and end plates are serviceable too...and the dude with the hairy back that's building it for you actually replaces the parts he's charging you for!

That said I've owned heaps and I love them...

4sfed5 wrote: The boost level you can run will be limited my the engine management you have....id stay under 10 psi if your using a piggy back or rising rate fuel pressure regulator over 10 psi you need a good stand alone ECU

i'm running 460cc injectors on the stock ecu using a dfa piggyback. they should be supplying enough fuel for more than 10psi, i think. this setup also should eliminate the need for a rising rate fuel pressure regulator.
note i haven't actually got the turbo on yet, but i know there is a guy in the states running the same injectors as me on the stock ecu and he's doing 14psi of boost without a rrfpr on a big turbo (edit - but he is running a walbro pump)

Hi Fatty.
While it \"can\" be done... cane it be done reliably???
There are a few guys who run big injectors (bigger than 330cc) on stock ecus and say they run fine but then you find out that \"running fine\" means crap gas mileage even worse cold start running and \"a funny flat spot on throttle tip in\". The big problem is that the higher the boost the more control you need on timing to stop things going bang. Things like the DFA are only a piggy back and so should not be relied upon at HIGH (12+psi) boost.

The reason i say this also is that the factory ECU cannot cope with a voltage from the afm above 3.9 volts at idle...And when using the emanage when you put in the correction for the 330cc injectors the resulting voltage is................3.9volts. so any bigger correction(bigger injectors) are NOT going to be in the realmes of the factory ecu to control. Under hot running off of the O2 sensor this effect isnt noticed however except on throttle changes and over 4000rpm running.