Boost Drop

[Guest]

Ok im having problem with boost drop everytime i boost it drops to 7psi and i have a boost tap and its set at 15psi and also running external wastegate.

Have checked all hoses and everything is fine.

So ideas anyone

[WRXONP]

which turbo is this on?

[Guest]

vf24

[Pappu1]

U mean it hits 15 then drops to 7 or what?

What rpm it hits boost drop

What gear

What petrol u using

What is gate spring pressure

[Guest]

yeah it hits 15 then drops to 7 around 4500rpm and thats in 1st

and every gear after that it stays on 7 and gate spring is 7.

and im using BP98.

[Guest]

im having the same trouble with mine atm.boost tap set at 16psi but after a certain amount of revs the boost drops to 14psi(standard).

i found it wasnt my tap.my internal wastegate cant handle the flow rate.it can spike to 16easily.but i cant hold it to redline.

ur external gate may be rooted.is it genuine or jus a cheapy?

[Pappu1]

Wat he said above could be a reason

Also have u checked if any ecu error codes

[WRXONP]

Iv found that externals work alot better with harder springs aye . . .

[Guest]

 sti8u']

im having the same trouble with mine atm.boost tap set at 16psi but after a certain amount of revs the boost drops to 14psi(standard).

i found it wasnt my tap.my internal wastegate cant handle the flow rate.it can spike to 16easily.but i cant hold it to redline.

ur external gate may be rooted.is it genuine or jus a cheapy?

oh true, mine drops down to 7psi. and im using genuine tial external aye. iv tryed both genuine and replica but no change.

Mite try hooking it back to the standard solenoid and see how it goes

Wat he said above could be a reason

Also have u checked if any ecu error codes

yup have checked for error codes and there's none

[quote name='WRXONP said:

Iv found that externals work alot better with harder springs aye . . .

thanks man will look into that.

[boon]

Was it running fine until recently or only when you put the external on?

Check that you've got the vacuum/boost lines on the wastegate the right way around, if you get them backwards it will just run spring pressure.

[WRXONP]

Na man if you have the actuator line on the top nipple it wont control at all you will free boost . I run a hose from the turbo compressor housing nipple to my boost tap then to the bottom nipple only on the external. Nothing on the top . The top is only used for electronic boost control or a air reg. My spring is 12 pound and the tap bleeds to 16

[Pappu1]

hmm try a different tap as well just incase its a bung tap...

[Guest]

 boon']

Was it running fine until recently or only when you put the external on?

Check that you've got the vacuum/boost lines on the wastegate the right way around, if you get them backwards it will just run spring pressure.

yeah it was running fine till i got the external on. it was holding boost at 1.2bar till redline.

have checked hoses and its hooked up right and arrow on boost tap pointing to wastegate

Na man if you have the actuator line on the top nipple it wont control at all you will free boost . I run a hose from the turbo compressor housing nipple to my boost tap then to the bottom nipple only on the external. Nothing on the top . The top is only used for electronic boost control or a air reg. My spring is 12 pound and the tap bleeds to 16

hahaha funny u mentioned that cause we had the hose on top wen we first put the wasty on and yeah it sure did free boost lol, but not recomended.

yup what you're saying we've done all that and still it boost drops. samething hapend at nitewars so was pretty much running 7pounds on the nite lol.

[quote name='pappu said:

hmm try a different tap as well just incase its a bung tap...

yup we thinking that too. so will give that a go.

[WRXONP]

if u run no tap do u get steady boost? i was getting boost spike on mine with my GFB tap due to the restrictor...drilled it out and now have no problems...

but all in all what boost do u want to run?? get a spring off trademe that suits you and run no tap...holds boost perfect

[Guest]

without tap its all goods and holds boost to 1.2bar till redline.

haha will try and get that before next nitewars.

thanks for your advise much appreciated

and will post up if we get it sorted

[WRXONP]

aye?? do u have a 1.2 bar spring in ur wastegate??

do u have the factory solinoid hooked upto the external?

[Guest]

nah i dont aye, its only got a 7psi spring in the wasty.

if i hook everything back to factory solenoid it boost 1.2bar without external wasty

[Guest]

i would say yu gota leak inside yur gate,check the diafram inside it.see if it has any splits or nething

[Guest]

Thanks will check that soon before the sun goes down lol

[WRXONP]

oh sorry bro im with you now... so with out the tap u hold a solid 7 to redline??

if u do then u aint got a faulty diaphram lol...

if u boost fine without the tap and shit with the tap on then its ya tap bro for sure... what sort of tap is it?? ball and spring?

http://www.trademe.co.nz/Trade-Me-Motors/Car-parts-accessories/Performance/Other/auction-357317220.htm

hardest one they have is one bar though... what u can do is get 2 springs (one has to be able to fit inside the other) and u can run say a 0.7 BAR (10.15 psi) and 0.5 BAR (7.25 psi) and that will give you your 1.2 bar

quote : For details on which are large and which are small diameter please see our website (this is only relevant if you wish to ruan dual springs to get more than 1 bar boost (14.5psi).

i have personnaly ran 2x springs in other cars i have owned with good results

hope this helps u man