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I have a stock R33. I plan to do the following in the next 12 months:

1. Pod filter or higher flow panel filter.

2. 3" mandrel bent exhaust in mild steel incld. dump pipe

3. FMIC

When is it safe to wind the boost up, and to what sort of PSI?

Also, is factory boost 5 psi?

I am thinking of getting a 2 stage bleed valve with a switch in the cabin (high & low). What is the benefit of an electronic boost controler apart from ease of use and a flashy box?

Thanks,

James.

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EBC have been proven

to hold boost more steadier you don't get any spiking

whereas as many time we have all said before

bleed valves aren't too good as they spike and shit

which cause your boost levels to go all over the place!

go the ebc even if you have to save more money

it's worth it in the end

cheers

adrian :)

The factory setting is 7psi on the R33 i think, i wouldn't wind it past past 14psi to be safe. Put simply boost controllers work similar to a tap on a pipe, adjusting it can allow the driver to raise or lower the boost pressure. By "tricking" the actuator (this controls the wastegate) into believing a lower boost level is being generated. This allows the turbo to generate more boost as the wastegate opens later.

James,

Bring her around we'll wind her up to about 20psi. It'll be right :)

If you want, I'll take you for a drive in mine and you can see what sort of spikes you can get with a bleed. James and I tuned my bleed valve, pretty easy.

I think mine spikes to about 13 and settles on 12psi. 10-12psi is ok on the stock cooler, but I'd get the exhaust done first.

EBC's will give heaps better results over a bleed, but so they should for about 5 times the price of a good bleed valve. EBC's will give you no wastegate creep, but you can get bleed valves that reduce wastegate creep heaps - but not down to zero like a EBC will.

I'd reccomend 10psi, maybe 12. If you want the turbo to last.

people run 14psi, with FMIC's, due to the pressure drop being only a couple of psi at this level, where as the stock cooler runs out of legs at this boost.

Bleed valves suck (although I have one). An EBC will hold boost and prevent the 'spike' associated with bleeders. Boost will be brought on faster and hold (meaning faster accelleration --- something that a dyno won't pickup).

If you intend sticking with the stock turbo and are not a regular visitor to the race track, put your money back in your pocket and don't buy the FMIC, unless you get one that only just flows say 300HP or just under. A cooler of this size will retain the valuable response and if designed well will allow a few extra psi without a serious pressure drop.

When shopping for an interccoler reccomendation ask :

" So how much horsepower can this intercooler you are reccomending flow?"

They answer " Mate this one is good for over 500HP! just what you need mate!"

You respond " No thanks. Which intercooler can flow upto 300HP max with some efficiency, cause thats all I am planning on making with this engine?"

Ditto for head porting, turbo sizing, camshaft selection, throttle body size etc.....

EBC is the way to go. I got one of those GReddy profec B spec. Highly rate it hey.

Lo boost set ot 7psi and hi boost to 11psi. runs fine. good acceleration no spiking etc....

even with no boost on it comes on kwcker too.

cost = $600 ish and then fitting + $250.00

ciao...

Mr Squiggle: Do you have a front mount or do you run that boost on the stock core?

So just to clarify, I should do the exhaust, the pod and get an EBC and scrap the FMIC?

Maybe spend the money on a new ECU?

Anything over 12psi would be a waste as the stock turbo is running out of it's effiency curve, for eg. at 11psi my car makes 184rwkw and at 12psi it makes 188rwkw so you can see it wouldn't be worth risking blowing up the turbo for another couple of kw that I might get at 13-14psi. Remember it's airflow that creates power not just psi, so a larger turbo at 10psi would make more power than I'm currently making at 12psi with the stockie.

Nissan turbo seals on teh exhaust side are only rated to 14psi from the factory correct... eh? The problem associated with a manual bleed valve is that they do spike like you are all saying, however the problem does lie within a stock cooler, where the pressure loss between the turbo and what reaches the intake manifold is destroyde dby the shitty flow and efficiency of the stock coolers. Most guys who are running around 10-12 at the boost gauge are actually pumping about 15psi or more out of the turbo because the turbo needs to push that much to make the 10-12psi at the intake cos the cooler looses so much. Definately if you are gonna do the main mod's most people do i.e. intake, exhaust, boost etc. Invest in a cooler and not only get cooler air and make more power but save your turbo from doing more work than it needs to and than it can take. After all if they are rated at 14 adn you have to put the turbo through 15psi to make 10-12psi then why bother risking it?

Nissan turbo seals on teh exhaust side are only rated to 14psi from the factory correct... eh? The problem associated with a manual bleed valve is that they do spike like you are all saying, however the problem does lie within a stock cooler, where the pressure loss between the turbo and what reaches the intake manifold is destroyde dby the shitty flow and efficiency of the stock coolers. Most guys who are running around 10-12 at the boost gauge are actually pumping about 15psi or more out of the turbo because the turbo needs to push that much to make the 10-12psi at the intake cos the cooler looses so much. Definately if you are gonna do the main mod's most people do i.e. intake, exhaust, boost etc. Invest in a cooler and not only get cooler air and make more power but save your turbo from doing more work than it needs to and than it can take. After all if they are rated at 14 adn you have to put the turbo through 15psi to make 10-12psi then why bother risking it? Not to mention spiking which can be +-2psi on a manual bleed valve which then throws teh turbo way out of both its efficiency range and safety range.

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