Max Safe Boost on R33 25T

Hey dudes

What is the max boost I can run safely on my car - R33 GTS25T - It is factory except for a k&n panel filter and 3 inch exhaust ?

Also does anyone know much about the Promuff brand of stainless steel muffler ?


Cheers

You can run up to 14psi with the mods you have as long as you remove the factory boost controller (which increases boost at around 4500 rpm) otherwise you should run around 10psi - either way you should get the car dyno tuned to make sure.

Hey J-spec im sorta in the same boat.
I have an R33gts25t, with HKS: intercooler, exhaust, dump pipe.
and blitz pod filter.
I want to know how to remove the factory boost controller like you said, and then whats a safe boost to run from my new turbosmart boost controller with the mods i have??

Andrew

I run a maximum of 12 with mine (exhaust, filter, TSBoost controller), and it can detonate at that level. I normally sit at 8psi. If I used high boost more often, I'd get the boost dropped to about 10-11.

IMHO 10-11 is safe. I know people who run higher, but they have ECU (and usually injector) upgrades.

so you think that with optimax (98 octane i think) i should set the max on 11 psi????

as I have posted many times before

...12psi is too much IF you still have the factory boost controller also because it will detonate and could cause damage
...with the factory controller removed you can run 13-14psi without detonation but should get it dyno tuned anyway just to know for sure.

...I will help anyone in Melbourne fit a boost controller and even arrange the dyno.

J-spec,

would you be able to tell me how to remove the factory boost controller??
Is it easy to do??

Andrew

IS JUST NORMAL UNLEADED OK IF U R RUNNING NORMAL BOOST??

Andrew,

removing the factory boost controller and fitting the TurboSmart one is easy to do, but maybe a little hard to explain simply - call me on 0414 502 250 and I will arrange a time to do it for you (at no cost)


denjam69,

These cars run on 100 octane fuel in Japan, so it is best to use Optimax (or other 98 octane fuels) where possible
if you don't have access to 98 octane where you live or just want to run normal unleaded fuel all the time, I would suggest taking the car to a good tuning shop and get it set-up properly for low octane fuel and you should be alright - personally I use nothing other than Optimax.

THANKS JSPEC! I HAVE BEEN RUNNING ON OPTIMAX BUT ITS COSTING ME ALOT OF $$!

OH WELL MORE OPTIMAX 4 ME THEN!

hey J-spec,
i Pm'd you before, and said that i live in mildura (top of vic)
So its very hard for me to take time off work and drive down there :(

But if its possible you could try and explain to me how to remove the factory boost controller that would be great.

Andrew.

ps, is the factory boost controller also called the solonoid? And is it a small trumpet looking thing mounted on the passenger side with a wire and a couple of hoses going to it???

I guess it's our crap kiwi fuel once again.

J-Spec, how can the factory boost controller cause detonation? I'm curious.

Hey J-Spec

Thankyou for your information to date.

I would also be extremely grateful if you explained removing the factory boost controller (I live in NZ)

Do you mean removing the hoses that are attached to the goldish boost solenoid and then connecting to the turbosmart controller, and also disconnecting the electrical connection to the boost controller (i.e black clip).

Is this it ? Or is it different, or is there something extra to do ?

Cheers
Ajay

yes, the solonoid is what controls the boost

removal is really simple (easier without the airbox in the way)
1..unplug the wires
2..remove both hoses from the solonoid
3..unbolt and remove the solonoid
4..grab the hose that came from the solonoid with the T join (should be still joined to the intake pipe and wastegate actuator)
5..remove the T part and put your TurboSmart unit in there
6..get the other hose from the solonoid (disappears down to the blow-off valve return pipe) and block it off with a screw

I will do a quick tech article for this soon (with photos) - meanwhile call if you need to be talked through any of it..

J-spec....you got any mates in syd that will do it for free too?? looking to get on in a week or so.

J-spec,
are you going to do the tech article on the J-spec website???
If so when do you reckon youll be able to do it by? That would be really helpful.

Andrew

Hey J-spec,
Heres a pic of my boost solonoid. It has the wire but only one hose going into it???? Dunno if this is right becoz everyone else says that u have 2 hoses going into it. Maybe something to do with the HKS intercooler?????

So could you please explain which hoses go where, and how to remove this and fit in the turbosmart (duel stage) controller???

Thanks,
Andrew

Well it appears that someone has already played around with your plumbing - I have an HKS intercooler in one of my R33's and the plumbing is still standard - here are a few things to do first....

it looks like the hose marked with a YELLOW line goes down to 20mm diameter black metal pipe that runs along the side of the engine from front to back (in the area marked with a BLUE dot) - if it is then you need to pull one end of that hose off the solonoid and block it up with a screw.

next you should just cut the hose marked with RED at one end and GREEN at the other and fit the TurboSmart Y-splitter part in there with the arrow pointing towards the GREEN.

then run a hose from the Y-splitter to the dual stage boost controller and mount it somewhere - keep all these hoses reasonably short for best results

run wires into the cabin so you can fit the switch

http://www.j-spec.com.au/engine1.jpg

I hope this reads alright nad is easy to understand - you can call me when you are in front of the car if you like.

nice heat shield!

whats it made from?

hey thanks heaps J-spec. that is REALLY helpful.

So youre saying i can unplug the yellow hose from the soloniod (where your yellow mark is) then block that up with a screw???Could i cut it shorter then block it up??? And im pretty sure you are right, that it connects up to a thick black hose that runs horizontal.

So then is the red/green hose the vaccuum line, because i was told by autobarn to fit it to the vaccuum line.

denjamin: its a turbo partition i got from Unique auto sports. It is a foam material with a reflective side on the other side. works VERY good.

also j-spec, do i do anything with the wire going to the boost solonoid??

Yes, you can cut that hose as short as you like and plug it up... make sure the screw is good and tight, maybe wrap a cable tie around it too - if it comes out the car will run rough

Yup, the RED-GREEN hose is your vacuum line that you cut to fit the new boost valve to..

as for the wires to the solonoid - just unbolt the solonoid and throw it out and cable tie the plug back out of the way

- don't forget to book a dyno run to set it up properly if you intend to run high boost (you have to be sure your boost guage is accurate)

ok thanks j-spec.

So the wires then arent used for anything after i swap over to the turbosmart controller then?

Also i live way up in mildura, and the closest dyno is actually in melb :(

So i cant really get to a dyno.... Im going to fit a speco boost gauge to it, so is this accurate enough???
I just cant get to a dyno, is it safe to do it without using one??

Hey J-Spec,

Excellent Instructions Man ! Thanks.

BTW do you know what the differences are between the old blue turbosmart controllers and the new red ones ?

Is it just the adjustment mechanism or is there increased performance with the red ones ?

In NZ there are no red ones for a few weeks, so I am considering buying the blue one this week . Should I wait or should I just get the blue one ?

Thanks
Ajay

the gauge might be accurate, but you have to be sure there are no restrictions in the plumbing and that it is running from the correct place in the engine bay - as long as you check it pretty well you should be alright.... and maybe only run about 12psi max. to be sure you don't get any detonation.


GraemeWi - to answer your question from before..

if you increase the boost to around 12psi with the factory solonoid still being used, when the revs reach around 4500 the solonoid will open causing the boost to increase to around 15-16psi which will cause detonation.

Ajay,

they claim to have increased performance from the new red ones because of a better gated design that allows the boost to climb quicker - in reality I have used both and noticed no difference apart from the appearance...
...I think for the cheaper price and easier install the old blue style is probably the best choice.

yeah im just not too sure where the gauge plugs into. Its a speco one so i think its a mechanical one (havent picked it up yet)

Originally posted by J-Spec Imports
if you increase the boost to around 12psi with the factory solonoid still being used, when the revs reach around 4500 the solonoid will open causing the boost to increase to around 15-16psi which will cause detonation.

This relates somewhat to my question in another thread. Do I need a boost controller to bypass the factory solenoid, and that annoying 2-stage boost thing? Or can I keep standard boost, but have it all from earlier on???

you do not need a boost controller to increase boost, but it is best to use one - and for only about $100, it is worth it to be able to adjust it in the future.

you could possibly wire the factory solonoid up so that it is open all the time giving you higher boost constantly - it would not be too hard to do, but I am not too sure if the solonoid has a one-way valve to stop vacuum leaking back through when the turbo is not boosting (if it doesn't then the car might not idle properly and could run lean)

I will be doing a little more research on the factory solonoid soon when I fit one to a GT Starlet turbo as a simple boost controller.

thanks for that - really just wondering if it were possible, cause the speed limit runs out before the higher boost comes on in 3rd :( :(

(not to sasy I've never felt it :devil: - that's why I really really want it from the beginning. Ah well, I'll be patient.

All,
There is one very important issue (I THINK) that has been overlooked.

Most people say 12-14psi of boost is fine for an R33 but arent aware of the fact that some of the series 2 R33's (one of which you may possess) dont have a turbo with a ceramic wheel or whatever. Apparently the alternative is plastic and can be disasterous past 12psi, in which case a conservative 10psi may be the most safe.

...if it is any consolation... they have cooler headlights and bonet :D

S'right. The series II R33 GTS25ts (all of 'em; unless you have a replacement turbo) have a plastic compressor wheel, which you can wave bye-bye to if you run too much boost. There isn't any hard and fast threshold, but the risk of this is much greater over around 12 psi; much like the risk of busting the ceramic exhaust wheels goes up above 14psi.

when u install i of those turbosmart boost controllers is it also necessary to install a fuel cut defender to allow more fuel to run through so u dont get detonation??

Why have nissan used a plastic turbo wheel ? How do you know this (not meaning to be rude) ?

And what other implications are there of this plastic wheel ? I thought the engines were meant to improve the newer they got ???

THEY MADE IT OUT OF PLASTIC SO IT SPOOLS FASTER!

1 ALTERNATIVE IS TO CHANGE THE WHEEL TO TITANIUM, VERY STRONG AND LIGHT.

LOTS OF BOOST AND FAST SPOOL!

Where do you get one of these & How much ?

Also will 11 psi be safe to run on my series 2?

all i know is that it cost big $$

seen a 12a rotary turbo club car that had a titanium wheel, was running 35psi and boost started at 2200rpm!!

preety sick

Guys,

i cant get my boost controller for a few weeks now, but is it possible to just unplug the boost solenoid (the hose) and then will i get 10 or 12 psi??? Is this a safe thing to do??

Andrew

NO - all that will do is reduce your boost over 4500rpm...

why can't you get a boost controller, where have you looked?
I can get them for around $100 from a number of places - let me know if you still can't find one.

yep i can get one, but its just going to take about a week :(

ok, so i wont unplug it yet then.

So where would you get a titanium wheel?

Zapf

zapf u asking me?