pum

can any one tell me what normal boost in psi is please for a my98 uk turbo and also what vacume you have on tick over as i only get 15 psi max boost is something wrong as madgrip is getting 19psi on his car which is a lot newer than mine. is mine fcuked

pum

come on guy's give me a break and say something

wanted

I think that 15psi is above standard m8, if madgrip is getting 19psi then it is well modded.

SiPie

Can only speak for an MY99 but standard boost appears to be between 10/11psi according to my gauge

Cheers

Dawes at 1.1bar seems to equal 15/17psi

Bit vague but thats what happens on mine

leeps

14.5 psi = 1 bar ....
normal boost on an my98 is about 0.9 bar ie factory standard
0.9 * 14.5 is = 13.05 psi ... thats standard
19 psi is 1.3 bar which is near the fuel cut line ive been told
so he must either be pumping more fuel in via a fuel regulator, management system ... etc or he is probably detting ...

* sorry it also depends what u mean by newer, the new sti's come standard with 1.1 bar boost ... so if its one of the later stis thats probably why, else he is probably increasing the fuel to the engine ....

leeps

[Edited by leeps - 9/19/2003 2:08:29 PM]

greasemonkey

You waited nine minutes between your first post and saying this? Give us a break, we're not "Pum's personal agony uncles"!

As Leeps has already said, your boost levels (if the gauge is reporting accurately) are already higher than they should be for a standard MY98, so on this score you have nothing to worry about.

As to Madgrip's being bigger than yours, he's obviously not driving a bog standard MY98, is he?

[Edited by greasemonkey - 9/19/2003 3:19:09 PM]

pum

greasemonkey, madgrip has an 02 bug eye, sorry if i seem a bit eager but no one ever post's when i ask something ...

so you think mine is not standard? all it has is a magnex sorst & well lane turbo dump valve, i got the car from well lane turbo center... same as mad grip.

alcazar

iTrader: (2)

I have a '98 Uk car, and it was 0.9 bar when it was standard.
Alcazar.

pum

whats 0.9 bar in psi plaese

The_Judge

I think 1bar = 14.5psi. So 0.9 x 14.5 = 13.05psi

Edited to say READ LEEPS's POST!!!

[Edited by The_Judge - 9/19/2003 5:49:35 PM]

pum

cheer's m8 any idea on what normal vacume is at tick over m8

The_Judge

Sorry, not sure. If my bloody boost gauge had turned up today, I'd be able to tell you... [img]images/smilies/mad.gif[/img]

greasemonkey

Maybe they do, but maybe you ignore what they say - as in when Leeps told you about converting from bar to psi?

Didn't say that. Could be your boost gauge over-reading - is it a decent one, or a £10 cheapie from a local Max Power outlet?

If your exhaust is a decat system, it could also be that it's promoting mild boost spiking. Does your car peak at 15psi, or does it hold 15 or so all the way through 4-5000rpm in 5th?

Regarding Madgrip's car, boost level for a standard MY02 WRX is 0.9 bar just like yours, and fuel cut should be 17psi. Thus, if his boost gauge is reading 19, we can only assume that it's either not a standard WRX (does he have an STi/PPP?), or his boost gauge is even more optimistic than yours.

Foot_Tapper

Just for a comparison , my MY97 WRX jap import is 1.1 bar and is standard, except for JR panel filter. And that , I am informed is what it should be.

Just to add i cant bleeding remember wot the vacuum is normally

[Edited by Foot_Tapper - 9/20/2003 8:57:39 PM]

greasemonkey

Your car may be supposed to run 1.1, but Pum's UK model isn't!

[Edited by greasemonkey - 9/20/2003 8:57:22 PM]

MadGrip

My car is an 01 Bugeye , all it has is a magnex cat back and a Forge VTA D/V ohh and something that people think belongs to the devil...a superchip & bleed valve.

It peaks at 19 psi and drops back to about 15psi I'm going to get a knocklink within the next week or so as recommended by greaseMonkey in a previous post.

I went back to where i bought the car and the guys there said that the chip will up the boost and trick the fuel cut but as long as its 19psi and not over it should be ok. I did turn th bleed valve down abit tonight so that it now peaks at 17-18 psi just to be safe,wont really know till i get the knock link & hopefully an AFR guage aswell.

While were on the subject and GM seems to know what he's talking about.. do you think 19psi IS safe for my car???

not trying to hijack your thread PUM.. by the way , glad your keeping your car mate, hope to see you at Elvington next week if your going

pum

will see you there m8, what does the knocklink do? and how much?

greasemonkey

I'm not terribly experienced running the TD04 to extremes Madgrip, so I'll be more than happy to quote Dr Banks, who suggests that 18psi in midrange dropping to around 14.5 at 6000rpm is about the limit for these turbos.

At end of day, if you've got a KnockLink (and almost as importantly an AFR meter) fitted, you won't have to guess about whether it's safe or not, you'll have most of the information necessary to be certain.

Pum, questions like this you should really answer for yourself by hitting the Search button, but seeing as I got up on the right side of the bed this morning...

A KnockLink detects knock, aka detonation, which is, to cut a long story short, the mixture igniting earlier than it should do in the cylinder due to heat, excessive compression, inadequate fuel octane rating or all of the above. Knock is the main enemy of turbocharged engines, as it creates very high stress levels in the reciprocating components and in time (not very much time if it's bad) can lead to a blown engine.

While the Impreza already has a knock sensor connected to the ECU, it is often not sensitive enough to detect the onset of knock, so a KnockLink and a dedicated sensor can in practice make the difference between you knowing it's knocking and backing off (and sorting out the cause), or carrying on in ignorance til your engine goes pop.

big500

Unless someone tells me different i seem to remember from my physics A level that 1 bar ( atmosphereic air pressure at sea level) is a metric measurement equating to a force of 1kg on an area of 1 squre cm. The imperial equiv is 14.7 psi therefore 15psi would equate to 1.02 bar and 1.1 bar would equate to 16.17 psi.
I'm not sure wether these small differences add up to anything but a blown motor sounds expesive.

Steve - new to scoobys but ok with science :-)

pum

thank's for your input steve

Scooby96

Apologies for a slight thread hijack - greasemonkey I've got a knocklink and also just bought an Apexi S-afc II - can the Apexi monitor the same things as an AFR?

Greeno

My boost gauge reads 18ish in the vacum side when idling...

Oh forgot to say it's a 93WRX Import...

G.

[Edited by Greeno - 9/22/2003 4:22:20 PM]

pum

mine says about 22 when at tick over

SiHethers

That'll be 22inHg (go figure!) vacuum, and that's about the same as my MY99 UK turbo. Think it equates to 10.8psi

Simon

iain atkins

You car sounds fine Pum, it's boosting a little bit more than the standard 0.9bar probably because of the exhaust system

pum

thanks for your input guys , my mind's at rest now

MadGrip

Just been tinkering and found that the t-peice to the bleed valve is broken so its been leaking

Probly thats why my boost was so high..

Off to get a new one now

[Edited by MadGrip - 9/23/2003 1:05:37 PM]

pum

oh well at least it should be cheap

MadGrip

new part fitted and what a difference. I think it must have been broken when i bought the car..

Now when the turbo kicks it give a real shove in the back, peaks at about 18psi and settles at 15psi.

well pleased

ok I'll shut up now



[Edited to say that the lumpy acceleration and hesitancy has disappeared aswell]





Phil

[Edited by MadGrip - 9/23/2003 4:57:42 PM]

greasemonkey

Sounds more like it Phil!

Scooby96, sorry, didn't see your reply hiding away up the top there!

No, the S-AFC II won't monitor exhaust gas CO (what all the "proper" AFR meters read) as it doesn't have a connection to the lambda sensor. If you're going to be using the AFC to alter the mixtures it'd be well worth running an AFR meter as a double-check.