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Guys and Girls, i have a 1995 r33 gtst with a turbo back zorst, k&n pod and a bleed valve that was set to 10 psi till last night when i draged my mate in his 33 same mods apart from the fact that he is running 14 psi. He was just at my house before and i got him to turn up my boost to 14psi and the car seems to be going so much harder.....but i have heard and read that with the mods that i have any boost over 10 or 11 psi would not only stuff up my turbo but also give me a down turn in performance due to the stock ecu cutting out. is this true ? if so how come my car seems to be going so much harder on 14 psi ??? and also has anyone with thet same mods as me (turbo back zorst, k&n pod and a bleed valve ) ever run 14 or mor psi and how did it go 4 u.

CHEERS

DAVE :D

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^^^ Agreed...forget about the crap about your ecu cutting out...i'd be more worried about you getting your exhaust wheel stuck in your cat or shooting it out your exhaust...keep it to 12psi or under...especially since you don't have a fmic as well...

i also have 3" turbo back zorst, pod filter. but i just put on a GREDDY FMIC, and have a power fc and a boost controller coming from japan. i was planning on 14pounds when i tune it in a few weeks. i have been told that the stock turbs can handle this for quite some time if they are in good nick.

i was talking to a guy with a 500rwhp r33 skyline who was telling before he built the monster he had that he ran his stock turbo on 18psi for 2 years and it was still perfect when he took it out of the car. He was saying that its all about have the supporting mods to ensure the turbo doesnt deteriorate eg a big exhaust to let the heat exscape fast, Good intercooler, ect ect. I wouldnt want to try it myself but he knows his shit and managed to make it work some how....

youve been told 3 times already, 14psi will kill it. intercooler wont make it safer, the heat associated with running 14psi will fry the exhaust wheel. the standard turbo is well out of its effiency past 12psi and will just throw in stacks more heat.

more boost means more power only when your in the compressors wheels effiency island from the compressor map.

after that its just more and more heat with diminishing returns per psi

fekuar

You mate was bullshitting.

He would the ONLY person in the world who was able to run 18psi in his skyline for any period of time.

My perfectly tuned R34 farked the bearings in it's stock turbo.

EVERYONE who has run 14psi for more than 9 months with their stock turbo has blown it up.

18psi = fully bullcrap mate.

wasnt a mate he worked for a performance engine company and advertises the company at car shows when showing his r33. Like i said i would like to see it done and wouldnt try it myself because i cant see it lasting more then an hour..... But he certainly wasnt deliberately try to bullshit anyone as he said this to more people then myself and that wouldnt be reputable for the company if everyone walked out and blew up their turbos lol

the factory ecu has excessive airflow protection built in. to protect itself from failure caused by excessive pressure. the ecu does not care how much boost you dial in, in fact it doesn't know how much boost you are running.

all it can see is how much air is coming via the airflow meter, once it detects too much over its trigger level it cuts the timing and runs really rich. this kills all the power. remember its not based on boost, but airflow meter "volume", upping the boost sucks in more air, which triggers the stock protection.

So is that just a load of crap that your ecu will cut out??......All this talk of turbos blowing makes me thinnk i should turn down the boost abit..  lol

IS 12psi with no cooler OK??

That's pretty much the max you want to run. It's all fun and games to wind the boost up and get more power, but you are putting excess strain on a lot of things.

You may well find that running 10psi with a really nice cooler could give you more power than 12-14 with the stocker. At least you're guaranteed that you aren't detonating the hell out of your motor.

Hot motor + cold air = power. =-]

It probably feel quicker due to R&R.. No longer linear but has power dips so it feels like the mid range screams then lays off a little then top end screams again. :P Well maybe not.. I'm just dribbling shiet. lol

Never wind up boost until you hit the dyno, you don't know the condition of your fuel pump, unless you have already replaced it with a new item. :P

Edited by Cubes

I personally have a RB20DET in my silvia with 500hp fuel pump, front mount, pod, exhaust only cat back at this stage, r33 radiator, twin thermo, custom pod induction, splitfire coilpacks....got more mods just listing main basic mods.

Im running 10psi....i use to run 12psi and im putting it back up to 12psi this week as the power from 10-12 psi is so much greater......my mate runs 14psi and damn it moves quick but i dont see that as a smart move and will laugh my ass of when i see the turbo go kaboom soon.

U have to think about cold nights aswell....how much denser the air is and it will be so dense it will make ur turbo run overtime since its sucking a higher volume of air so u must set ur boost up smart.

- Luke

fekuar

My perfectly tuned R34 farked the bearings in it's stock turbo.

EVERYONE who has run 14psi for more than 9 months with their stock turbo has blown it up.

Except me :P

I must have some freak turbo... sees 0.9 bar peak boost every time I drive it.

Doesn't matter, it's being upgraded very soon B)

RB20DET_Silvia

I ran 1-1.1bar for a solid 100,000km's on my rb20det turbo, std boost was 11psi.

It was running lots of ign. timing and slightly rich (in the 11's).

Mine was only street driven, no big long 4th gear windouts.

Its well known the rb20det turbo on the rb20det motor handles 1bar no problems, the rb20det at 15psi has similiar airflow to the rb25det at 10psi.

Edited by Cubes

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