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most set ups do this anwyay, unless you have a decent EBC. but the vast majority of stock turbo equiped cars once fitted with exhausts, fmic and the basics, will spike in the midrange, then settle back a few psi.

dont be a moron, and stand by your 12 psi kills turbo's BS, unless you have significant proof other then "other people have run 12 psi and their turbos have died" this doesnt take in account of how many kms the turbo has done, the service history, etc.

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hey guys,

currently my car (r33 s2) has the following modifications done:

- pod

- 3" catback

- 34 smic upgrade

- running 12psi

i have had it dynoed at bd4s and achieved 180rwkw, im planning to get the f-con v pro with the evc 5 (will be running 14psi). bd4s have told me that they can make 200rwkw, so the question is - would this be a safe tune? the reason i ask is because there are other skylines (same model for comparison) with twice as many modifications (comparing against cars with fuel management systems and other modifications) making only what they promised to get for me. any inputs guys? i just dont want to make that kind of power and end up blowing something later on.

cheers

mate ive got nearly all those mods aswel (bar the 12psi boost increase, mines on about 8.5ish psi)

how does it run on 12psi with no aftermarket piggy back comp or ecu? i thought u can only run over 10psi with some sort of engine manigment stop it from misfiring and stop it from retarding itself..

cheers

Service the car regularly and get a good boost controller. Ive seen enough rb25s with the stocker running 14psi last much longer than a year, thats enough evidence for me. But in saying thats only what i have seen personally. As with anything your taking more of a risk than running it from standard boost pressure.

Crank it!

wind boost into it until it hardly makes more power. (which will probably be around 12psi +/- 1psi)

drive it however you like.

replace turbo when it goes bang.

pretty simple.

if you can't afford a replacement then be conservative in how far you push the set up and how hard you drive it.

they dont give you any more puff over 12psi anyway...

i pushed mine out to 16ish and my extremely accurate seat-of-the-pants-dyno gave me the exact same reading as at 12

and yes... HEAPS of people have blown them going for 14+

i got similar mods to my R33 GTST (exhaust,FMIC,pod,boost controller) and just got a emanage ultimate and spit fire coil packs put in yesterday. Getting it done at CRD in Sydney and they dyno'd the car and achieved 238rwkw at 15psi on high boost. Its running on about 9psi on low boost which i use for daily driving.

they reckon its all in the tune. mate got the same thing done to his r33 bout 1.5 yrs ago and he is running 16psi no probs on stock turbo.

i got similar mods to my R33 GTST (exhaust,FMIC,pod,boost controller) and just got a emanage ultimate and spit fire coil packs put in yesterday. Getting it done at CRD in Sydney and they dyno'd the car and achieved 238rwkw at 15psi on high boost. Its running on about 9psi on low boost which i use for daily driving.

they reckon its all in the tune. mate got the same thing done to his r33 bout 1.5 yrs ago and he is running 16psi no probs on stock turbo.

LOL

That is all!!!

i got similar mods to my R33 GTST (exhaust,FMIC,pod,boost controller) and just got a emanage ultimate and spit fire coil packs put in yesterday. Getting it done at CRD in Sydney and they dyno'd the car and achieved 238rwkw at 15psi on high boost. Its running on about 9psi on low boost which i use for daily driving.

they reckon its all in the tune. mate got the same thing done to his r33 bout 1.5 yrs ago and he is running 16psi no probs on stock turbo.

hi,

there could be many reasons for the inflated figure - i would doubt the 238kw with 16psi on the std turbo and std GTST setup

i would expect there is something to the puzzle that we are missing, the dyno sheet would help clear up some issues

the usual culprits that inflate dyno figures;

- 3rd gear instead of 4th

- aftermarket turbo when owner thinks std

- highflowed turbo when owner thinks std

- different diff gears

- inflated intake temps (IT on the dyno plot)

- different style dyno ie: hub dyno, or dynapack (us style etc). - most people expect dyno dynamics shootout

- mixup of shootout mode vs non-shootout mode (you shouldnt compare the two)

- incorrect ramp, load, shoot style settings (ie SHOOT4F on 6 cylinder car)

etc etc

as you can see there are lots and lots of reasons for the inflated figure - sure it could even be a legit 238kw figure but its more likely to fail

mate ive got nearly all those mods aswel (bar the 12psi boost increase, mines on about 8.5ish psi)

how does it run on 12psi with no aftermarket piggy back comp or ecu? i thought u can only run over 10psi with some sort of engine manigment stop it from misfiring and stop it from retarding itself..

cheers

there is a simple answer to this - imported.

being the second owner in australia (first owner only owned it for 2 months) there is just no way of knowing what has been done to it in the past. i have investigated some bits and pieces before and have found evidence things have been added in then taken out (spare wires and such), but what ever is left in the car that i can physically see has been either left stock or changed back to stock bar the engine internals which i have not checked.

i ran 15 psi on my standard s1 turbo for 6 months no prob.. the motor shit itself.. so i bought a s2 half cut turbo and all.. running the same boost lasted 2 days... and the motor muched on it so it lasted the same lol.

hi,

there could be many reasons for the inflated figure - i would doubt the 238kw with 16psi on the std turbo and std GTST setup

i would expect there is something to the puzzle that we are missing, the dyno sheet would help clear up some issues

the usual culprits that inflate dyno figures;

- 3rd gear instead of 4th

- aftermarket turbo when owner thinks std

- highflowed turbo when owner thinks std

- different diff gears

- inflated intake temps (IT on the dyno plot)

- different style dyno ie: hub dyno, or dynapack (us style etc). - most people expect dyno dynamics shootout

- mixup of shootout mode vs non-shootout mode (you shouldnt compare the two)

- incorrect ramp, load, shoot style settings (ie SHOOT4F on 6 cylinder car)

etc etc

as you can see there are lots and lots of reasons for the inflated figure - sure it could even be a legit 238kw figure but its more likely to fail

yeah to be honest i was a bit like WTF when they told me. I was expecting like 190rwkw max. Not to sure what the go is but im heading there tomorrow morning so ill sus it out. Could be a highflow turbo havent really checked.

  • 2 months later...
they dont give you any more puff over 12psi anyway...

i pushed mine out to 16ish and my extremely accurate seat-of-the-pants-dyno gave me the exact same reading as at 12

and yes... HEAPS of people have blown them going for 14+

as someone who ran 14psi for quite a while, and having mates who have all done it also without any problems, i can say that your seat of the pants dyno is out of whack. i noticed a big difference going from 11psi to 14. and another friend of mine stuck his car on the dyno. started at 200kw at 13psi and then wound up the boost and went up to 216kw at 16psi. i have heard so many people on this forum say that you won't make any more power by going above 12psi and all i can do is laugh, cause 99% of them have never tried it and only say it because they read it on here somewhere (same goes for rich and retard). none of the people i know that have run high boost have blown a turbo, yet i know someone that had a turbo let go at stock boost and a few people that have had turbos let go at around 11psi.

now while i will admit that you are heading into the unsafe zone at anything above 13psi (and that if your turbo is a bit weak this will put it over the edge), people that automatically assume that once you go above that pressure your turbo WILL DIE just shit me off. the reason being is that there are plenty of people not on this forum with skylines running that sort of boost and not having any problems. it is just that on this forum you hear about the people that do have it happen.

i am glad i read all of your comments because i have just finished my rb20det conversion and was wondering what boost to run...

my mate runs 14psi in his skyline everyday and well he drives like a pussy so that doesnt count.. but what i want to know is.. If i want to give my car a good proper driving like it should be drivin!! (not like a pussy) then what is the safest max psi? realisticly?? 10?

however i only have a turbosmart Tpiece (not a bleed valve) will this still spike?

thanks guys, very informative.. even though your all arguing hahahaha

Been on this forum since 2002 and seen this argument for as long as the forum has been around.

I think most of us would love to be able to say with confidence " bump it up to 14psi mate, it rocks! ". However, over time it's just very apparent that such a reccomendation is contrary to seeing the results of members having a go at the idea.

In time, the 14psi get to see a dead turbo sooner, alot sooner than people who stick to the 10-12psi rule of thumb. I would also say exhaust gas temp has something to do with the increased chance of failure in addition to shaft speed as well. If you do go the 14psi road then a good electronic boost controller is a smart idea to ensure you don't spike beyond.

So whilst it's actually true that you might be able to run about with 14psi and not see the down side for a while (and people have done), you can be sure that the life span is very significantly shortened. If you have a turbo with a few kms on it you might be best to stick to a more reasonable limit of 10-12psi and get some extra power elsewhere till you have the coin for a new turbo.

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