Overboost

[Dave_the_B]

How much does yours overboost?
Mine goes up to 19psi then settles to 15/16psi. Is this common or should I worry?

Cheers
Dave

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Grey S13
T28@16psi
Evo 6 IC

[Matt_S]

Hi Dave - Are you using a bleed valve?
If so, I think what you're seeing is whats known as a "boost spike".
No getting round it using one of these. Best way is to get yourself a controller, although from what Barry's told me, it needs to be a decent one. Apparently his old controller worked fine with a T25, but the T28 made it go haywire!

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Matt
'92 S13
1/4 mile mad!

[SteveSadler]

which controller have you guys got.

Profec B?
Apexi S-AFC?
Blitz?or
HKS?

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Bayside Blue S13
Mild Mods
I reckon around about 240BHP.

[Nathan_200sx]

I spoke to simon Norris ages ago when my actuator was hitting 22psi and coming down to 12psi and he said it should peak at 18 and drop to 15. even now with the boost controller it still peaks at 20psi and settles to 18psi. so I wouldnt worry to much, just keep an eye on it and make sure it doesnt get worse and peak at 25+ like mine did in the end http://300zx.co.uk/200sx/ubb/eek.gif
BTW steve I'm running the profec B, very easy to fit and use. only one gripe though dont get the clear blue one like I did, when they illuminate at night it looks pants.

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Nathan
Red S13 Mongoose, K&N T3 280ish BHP http://mysmilies.com/smilies/cwm30.gif
Empty bank account

[Chimp]

20psi on a t3

yoo h00ligannnnnnnnn

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Dan
Red S13
Actuator/chip/filter
blue smoke, crunchy crank

[Funb0b]

Matts is right you will always suffer from boost spikes, but a boost controller like the AVC-R is able to learn the boost curve for each gear and smooth the spikes quite conciderably, giving a more stable boost pattern.

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Barry S13
See [URL=http://www.puresx.co.uk/Barry's%20S13.html.uk]
for spec

[Dave_the_B]

I am using a Ric Gillis turbo boost valve, www.boostvalve.com (http://www.boostvalve.com)
This is not a bleed valve but a ball valve which fits between the turbo and the actuator.Wind the little knob down and up goes the boost,very easy to fit and adjust.

Dave

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Grey S13
T28@16psi
Evo 6 IC

[Danny]

Boody el, you guys running 20psi 'n' stuff, have you lot got better pistons or something, im scared to even go past 15psi.
whats the most you can run anyway

[Mike_S13]

According to to Norris Designs, you can run upto 22psi using standard engine internals -not a standard t25 turbo though!!!

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Red '93 S13
A Few mods

[Paul_S13]

Originally posted by Danny:
Boody el, you guys running 20psi 'n' stuff, have you lot got better pistons or something, im scared to even go past 15psi.
whats the most you can run anyway

I'm running 17-18psi with a T25 hybrid, the only problem you might have is if you fuel pump is tired then you won't be able to chuck enough fuel in at any pressure over 15psi.