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hey guys, just a very quick one, on my R33 i have a 3" turbo back xhaust, mines computer chip, apexi super intake, hks ssq bov and one or 2 other minor mods.

i have just bought a greddy phneumatic boost controller (good unit should only spike max of 2pound) and i will hopefully fit it in the next fortnight.

however i may not put it on as im slightly concerned that im not running an FMIC, i want to run 12 pound but i fear i may harm the car if i dont have an intercooler.

do you think it will be ok to run that boost without it? if its going to hurt the engine i'll turn it down to stock psi during the day or when its hot and just run higher boost at night. and i obvioulsy wont be running any higher than 12 as its still the stock turbo.

so in short can i run 12psi without an FMIC relatively safely?

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well for a start, you DO have an intercooler...

the first issue is that at 12psi there is a flow restriction in the stock intercooler. so if you use the stock intercooler and your boost gauge reads 12psi then in actual fact you are probably making around 14psi with 2psi being lost across the stock cooler. with a FMIC there is usually negligable pressure loss and 12psi at the boost gauge probably also means 12psi from teh turbo outlet.

the second issue is that upping the boost on an intercooler of relatively small surface area will result in minimal cooling of the compressed air and consequently higher intake temps. this may lead to detonation.

so... my advide would be to run 10psi on the stocker and wait for a FMIC before you up it any higher.

but others will probably tell you otherwise so follow your instincts.

cheers,

Waz.

i c, well 10psi will still make a huge difference im told from stock, im just over being beaten by ss commies cause i only have stock boost, and after 8months of not running higher than (is 5pound stock?) its starting to sh*t me.

its not likely i'll be getting an FMIC as, all my money will be going into my house, otherwise i would have bought an EBC to start with. but 10pound is still enough to make a big diff so it wont be to dissapointing.

10psi will definetly make a difference, if you run higher ie around 12 or 14 you will find a even more of an improvement but not as drastic because the stock IC is too restrictive.

The stock cooler also heats up too much faster with so if you run high boost and are not moving fast or its a hot day u will lose power after a while (not heaps but noticeable)

U wont harm the engine, more likely to kill the turbo so dont worry about the engine..

i ran upto 1 bar for about 7 months with stock cooler and catback (had a air leak didnt realise)

the car lost a alot of performance when i put it back to stock boost :)

and yes about 7 is stock boost but with turbo back exhaust it would be probably around 8psi.

stock is around 5 or so pound at low revs but when you hit higher revs (around 4500 i think) boost will rise to around 7psi. if i were u i would leave it around 8psi, you should be able to take any commy with that. Save up for a computer and a cooler then you can happily run 12 all day long.

yeah this is true, the b/c only cost me $50 which is great as its a good unit, i never intended to run more boost, i had just planned on selling the car(money for the house), but now it seems as though i will need to keep it for work.

so somewhere down the track i may get an FMIC but for now i guess i'll just keep it around 9-10pound and dial it up to 12 if anything lines up next to me.

if i blow the turbo i'll get over it, just an excuse to buy a big one.

Mines stock as and its running in 7psi

Don't any higher than 9psi with the stock cooler (I personally go any higher than 7Psi, for safety sake),

Everything in the first reply is absoultly correct.

It is not worthe the risk, realibility issues, go spend $1149 on a hybrid intercooler kit, install it yourself, put boost up to 10Psi, and have fun, that should be a vast improvement over 5Psi. Plenty of people go over 10 Psi on stock turbine and computer but I dont thing it is a good idea, you will run into boost cut (by ECU) problems causing and catastrophic failure of the ceramic turbine. Dont go above 10Psi.

BTW: WTF is a "mines computer chip" I have not found anyone that replaces the R33 ECU chip, what am I missing?

i ran 10psi with stock cooler for ages....it is safe as houses....

next step is a fmic tho...then you can run 12psi easy....

FYI: stock cooler is so retrictive that you lose about 7psi apparently just going through it....so when your running 10psi at your engine you turbo is actually doing 17psi.....thats why so many ppl have their ceramic exhaust wheel fly out their exhaust pipe....

stock cooler: 10psi

fmic: 12-13psi

2ez....

ps. no use really running more than 10psi even with fmic unless you have some sort of management like a safc as it will run way to rich and you wont get any gain out of it.....prolly just keep blowing intercooler pipes... :)

I ran 13psi for at least 6 months with the stock intercooler. It worked for me, so 12psi should be ok. I just wouldnt be racing around a track all day with it. Bursts here and there is fine. Half a dozen continous dyno runs are not ok, heat builds up quickly, but with some nice cool air in Canberra, 12psi would be fine.

you'll see fark all gain running much more than 10-11psi through the stock turbo anyhow so just leave it around 10-11 and be done with it.

Any boost controller that spikes isnt a good unit at all :)

My good ole bleed valve dont spike at all. Get too 16psi and stay there, doesnt go over.

Andrew - I ran 12 psi on my stockie for about 12 months and it was fine, bit I do drive like a granny :) . But the thing I'd be worried about in your setup is the ECU.

Being a Mines ECU (and probably tuned in JP) then it'll be tuned for 100ron. So turning up the boost might get it to ping. Plus summer is on it's way and you know how hot it gets in Canberra :)

I'd keep it safe at 10psi for now.

J

ok well the general feeling here is that 10psi should be fine, but going over will, possibly screw with the turbo, not allow me to get any more power after 12psi anyway and make the car to hot.

so i think for now, it will set it at 10/11psi, and on the hotter days, wind it down to 9ish.

also, i have no idea what a mines chip is either, i was just told that the car had one when i bought it, i have no idea how to find out, i just had a quick look in the boot and the ecu looks stock, just a silver box. i'll take it out tomorrow b4 work and check it out, to see if theres anything different. but if theres a "chip" in there i wont be able to find out.

sounds like bs to me though, i never really trhought much of it till now.

Cool,

Oh, the ECU isn't in the boot :) It's under the passengers side kick panel - where their left foot sits.

Pull the plastic panel off and you'll see the ECU. It might have stamped on the cover that it's a Mines, or you might have to unscrew the cover and have a look at the chip etc...

Mines ECU's tend to run more timing advance than the stock ones, so this could make it a little prone to ping.

J

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