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R34 gtt RB25det series 3 2001 skyline (automatic)

Steel blade turbo

mods:

Turbo back exhaust 3 inch

Jrr dump pipe 3 inch

K&N Filter with stock airbox

apexi turbo/ Air fuel/ o2 sensor/ timer( if that helps :S)

What is the max psi i can run Safely without a FMIC?

cos im thinking of getting a manual boost controler do i need anymore parts aswell so i dont get boost cut. and what psi will it boost cut anyway?

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There is no "safe" boost level. An SMIC will heatsoak faster than an FMIC due to the small surface area, so i'd say even on standard boost you'd be getting good heatsoak on a hot day. Save up for an FMIC man.

Exactly - there is no set boost figure... End of the day the stock SMIC is rubbish.

Without a proper ECU & tune, there is little point increasing boost as most ECU's hit the age old "rich/retard" mode when you increase boost to anywhere from 9-11psi. Some cars it kicks in at 8psi for example. It's just luck of the draw.

A good tune will do more wonders for the car than just upping the boost and having the stock ECU shit itself.

i would be more worried about the turbo then then induction, Altough my mates Rb30det with 240,000km on it was hammered for years with a manual boost controller at around 12-14psi and no dramas,

Correct me if im wrong, But thoes old holden rb30det VK's didnet even have a side mount?

The overall point is this. On the standard turbo and standard management, there is no boost limit resulting from the SMIC being too small. The management gets in the way of progress before the SMIC does. With a tuneable ECU, you can probably still run the standard turbo up to the sensible maximum with the SMIC anyway. That's in the order of 12 psi, and results from the increased risk of death of the ceramic turbine above that boost, and also the fact that you will be getting close to the max on the injectors also. On a street car just being driven around normally (pont, squirt, hide from the cops) you'd probably not even notice that the SMIC was a bit undersized. Extensively thrash it through the hills or give it a dyno session and you'd probably end up having to tune it richer and with less timing.

If you go past all of that onto a different turbo/injectors etc, then you'd be foolish not to put a FMIC on it. Having said that, a decent FMIC is really one of the earliest mods that could/should be done. Reduces pressure drop, makes more cool, which takes the load off the turbo and the exhaust temps and so on and so forth.

Question is, how cold can you keep it? imagine that SMIC covered in dry ice, then hey run as much as you want through it.

On that note, many 1.8T Audi boys use their stock sidemount and ram 1bar boost through it using remaps, they seem to be all running fine.

As far as reports from R34 SMIC users go, 200-220kw seems the max you can get from a R34 factory sidemount. The upper limit of 240kw with a ARC sidemount. But there is no escaping heatsoak on a SMIC, hotter the air the less power you make.

On that note, many 1.8T Audi boys use their stock sidemount and ram 1bar boost through it using remaps, they seem to be all running fine.

I think you'll find a 1.8T turbo @ 14psi will probably be flowing as much as a RB25DET turbo does at maybe 5-6psi

Not just about pressure, it's also the airflow restriction and the ability to cool the air being sent

As far as reports from R34 SMIC users go, 200-220kw seems the max you can get from a R34 factory sidemount. The upper limit of 240kw with a ARC sidemount. But there is no escaping heatsoak on a SMIC, hotter the air the less power you make.

Id like to see any smic not get heat soaked at those powers with consective power runs or working the car hard for several minutes. They might work for giving a single squirt every once in a while thats it.

the smic is rubbish for anything over standard boost

if you increase boost, change the intercooler core, simple

forget about 200-220rwkw is fine on standard SMIC

its not and its ass. its been done to death. find the thread about 4years when rekin tried to keep the SMIC on his 32 and use the 34 SMIC

it was ass, we all said it was ass and it was ass. a new FMIC should be around $600 installed ish anyhoo so you would be mad not too

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