Those of you who have knowledge! in this area - meaning you may not have them on your car!

Is the lenth of pipe critical to match existing, or can 'one' replace with better rubber, to accomplish an easer fitment.

 

harve.

Harve, fairly certain if your replacing rubber it's not a problem, as it's the jets design that does the job in hand, as long as it's a nice tight fit, smithy

Length is not important . Diameter of apeture of the jet is obviously cruicial the small the hole the higher the boost.

 

 

 

 

------------------

Z ya

 

Nico91TT

 

Oh Nico - we're going to have to debate this one as well !

 

The smaller the hole, the less air is bled off and therefore the lower the boost required to actuate the wastegates.

 

With a bigger hole, more air is bled off prior to the actuator and therefore the more boost must be generated before the wastegates operate.

 

I've re-read that and am unconvinced that I've explained myself properly - do you get what I'm saying ?

 

Or can boost jets be fitted in two ways ? Mine were certainly fitted as a bleed off the main pipes, rather than as a 'blockage' in those pipes.

 

D

You're right I think Hairsy - there are two ways of fitting boost jets..

 

SE way is a bleed (having seen AndyP's car)

The JWT way is, if I recall correctly, by way of a restriction in the actuator hose going to the turbo, so yep, the two work in opposite ways when it comes to hole dia.

Or the proper way is to actually buy a boost controller?

being serious does that not cause wavy boost. Ie your more prone to boost spike and bleed. Once you get to certain boost it wont hold very well.?

Or am i wrong ?

They're all 'proper' ways, been done for years and years.. but..

 

Yes, boost jets (either bleed, or in line) will be more prone to boost spikes than a boost controller, because of the way they work.

 

Boost jets/bleeds limit the amount/pressure of the air reacing the actuator diaphram;

 

Whereas with a boost controller, *no* air reaches the actuator diaphram until you hit your target boost, at that point the boost controller opens long enough to pressurise the actuator, when the boost starts to drop below your target amount, it closes again and bleeds the pressure back out of the actuator, causing boost to rise, as it hits your target boost, it opens again, filling the actuator, and so on in a never ending cycle..

 

You (warren) probably already know that, just thought I'd include it for completeness.

 

Some US cars, possibly all, have been found to already have restrictors in the actuator hoses, to bring 'standard' boost up to 7psi (stock boost without the BCSV's open)..

Hehe Hairsy my Arch Nemesis where have you been

 

I Think everything has been explained by my good friend (untill he wouldn't buy me a pint that is) Az.

 

I use the Inline way - The Bleeder is a lot more popular on the Supra's but is still used a fair bit on Z's.

 

Whoever said it was correct in that mine (inline)

Smaller = + Boost

Yours (Bleed)

Larger = + Boost.

 

Boost controllers are better in the way they controll boost thru the duty cycle leads to less flash boost.

 

 

 

------------------

Z ya

 

Nico91TT

 

WOW, so much info to get ya head round

The reason for my post in the first instance is:-

MOT failier on co, nearly hittin the 4.0, & at the rolling road day the heavy foot in my car said how do i turn up your boost as ive got way too much fuel going in.

The car was owned by MK performance as there "look see" car, as my pipes were all over the shop (Thanks Andy Duff) he put them right at the April meet.

All the goodies were taken off the car for the previous owner, apparently the bigger injectors were left in - explaining the above, so the welding tip job is now iminent as i typed to slow last night to get the boost controller of off matey on the isle of white DOH. A Z dialing wand group buy LOL.

Running that much over fueling & havin' a van full of different size tips, & being able to re-drill at .1 diamiters if needed have you any ideas what might be the max before a plink apears ???

 

 

------------------

Harve,

 

Seriously, I would really, really reccommend getting an aftermarket ECU first, or at least an air fuel controller..

 

You're running bigger injectors you say, which means you're overfuelling - but that doesn't necessarily mean that the maps will actually be right to cope with extra boost.. you're playing a dangerous game there..

 

as for how much can you do... i wouldn't go over 12psi.. actually no, i wouldn't go over stock until I had an ECU, but that's up to you...

 

remember, upping the boost is going to do f*ck all to alter your CO though for the MOT, so you're still gonna fail!! and you'll still run mega rich off boost..

in fact, if it really has uprated injectors, i'm surprised it runs well at all.. even 555cc injectors are quite a big jump from stock..

Touch wood, !!!

The car runs as sweet as a nut, more than happy with it, local heros arnt though LOL.

All info is greatly accepted, thanks.

I understand the boost limits on the welding tip jobby, but if it proves good for a test ok - if it has 1 single plink its going to as std and ill have to do the fsp pipe again for the MOT next year .

But if more fun is at hand its mine.

If the MK performance company hadn't gone bust i'd be laughing.

 

started at 1.5mm, and left it there,

idle-stable, no-dettonation, rev down sweet,

different engine, quieter, diagnostic spot on, & big foot mode JESUS !!!

All in an effort to keep up with overfueling,

will get absolute psi on tuesday.

It feels like the first time you drove a Z.

 

A can't stop grinnin'........harve

 

------------------

Gonna get some welding tips for Nico's inline method,

What is the outer diameter of the tip to get a tight fit or are they a standard size?

 

Cheers

 

Jay

I think they are a standard size, I got some in Halfords for about £3. Harve will be the expert though.

Originally posted by AndyP:

I think they are a standard size, I got some in Halfords for about £3. Harve will be the expert though.

 

Any idea of the o/d of your ones?

6mm.

 

If you dont have an (aftermarket) ECU, then *please* dont do this.

Originally posted by aaronjb:

6mm.

 

If you dont have an (aftermarket) ECU, then *please* dont do this.

 

JWT should be here soon, just getting all the bits ready

Just checking

 

Get some 1mm, and 0.8mm, and maybe 1.5mm - start at 1.5 and work up until you find between 12 & 14psi..

 

Smaller being higher with Nico/JWT method..

 

I imagine Harve used the SE method (bleed)..

Didn't have any 1.5's so I got some 1.2's to start with, really expensive though - cost me a whole pound for the pair

 

Gonna drill them out to 1.5 & see how they go to start with, any idea of bhp increase at 13-14psi?

Have you got an accurate boost gauge ? - you know it makes sense.

 

At least that way you can see what boost you were running when you're engine blew up !!

Ordering gauge this week, just trying to sort out a pod

I have a dual 52mm pod that I'm about to send back to Smithy. If you're interested we could possibly save some postage here - you pay him and I'll post it to you. Brand spanking, never been used, £65 all in. It's a lovely piece of kit that replaces the standard Nissan a-pillar moulding completely.

Cheers mate, but don't want a pillar mount one, want it on top of dash.

 

(edit)

I want this sort of thing

Just realised my mates dad can probably build me one out of fibreglass (he's a fibreglass god).

Better than paying the $280 from Stillen

 

[This message has been edited by JayPSC (edited 14-01-2002).]

Thanks for your concern Aron mate, but i think i took the safe method, 6mm o/d tip, re-drilled to 1.5mm bore, boost showing 14 psi on car but have a oil filled super accurate one to give Tony in the passenger seat 2moro' then i suspect it will show 11-12 psi. Then its off to the mot station to see what the CO reading is.

The surge of grunt from 3000 rpm & up is considerable.

STD tips are 0.6-0.8-1.0-1.2, i drilled to 1.5 to be safe. If anyone wants any they cost me f/a, so free exept p&p

NOTE i only did this to keep up with overfueling, NOT HP GAIN!

 

------------------