boost issue

[ash_uk2000]

i got a uk2000 and just fitted a decat straight system but since then it feels as if it boosts then holds off and boosts again and feels jerky at 3k when boost is cutting in?

[Scott.T]

what year is the car ?

[ash_uk2000]

98

[Scott.T]

ok.
there's no easy way to map a 98 to get the best out of a decat exhaust other then a new ecu or a daughter board from esl.
what's probably happening is overboost and fuel cut.

if you can get the boost back under control it should be safe to run without a remap.
To do this you need to increase the size of the hole in the boost restrictor by about 0.1 - 0.2mm.
this brass restrictor is inside the 3mm boost hose that connects to the turbo outlet.

[ash_uk2000]

to be honest i havent a clue how to it defo dont feel as quick as it did before the car is standard bar baileys dump valve

[C. J.]

Speak to or email Simon@jollygreenmonster.co.uk

[Scott.T]

If it's a remap your after then talk to the man recommended above.


Changing to decat should not loose you power unless something has been done wrong or changed.
An MY97/98 should be fine, although sometimes the decat can cause overboost / boost spikes which the ECU then tries to correct or trigger fuel-cut if the spike is very high.
The MY99/00 is a little more tolerant.

If you just want it to run right then check these hoses havn't been replaced with shiney new silicon, and make sure Hose No.2 still has the brass restrictor in place.

If it does have the restrictor in place are you able to confirm what boost you are seeing ?????

If it's boost spiking then do as I mentioned above. Take the restrictor out and enlarge the hole in it by about 0.1-0.2mm.
YOu can run without the restrictor but you will only hit about 0.5bar (around 7psi) boost.

[ash_uk2000]

ok cheers ill have a look tomo i cant afford re map at the mo plus want to get better fuel pump and sti top mount and bigger injectors if i need them?

i only want about 280 bhp is that easy to get as what is it now about 220?

[ash_uk2000]

it doesnt have any boost gages so i cant tell at the mo i have only just got it and its pretty standard bar the decats and baileys dump valve

[asperformance]

is the coilpack mounted centrally on the inlet or to the pass side??
this would confirm if you have a 98MY car or a 98 reg'd 99MY car............

97-98 cars can be ESL mapped and 99-00 cars Ecutek'd

your injectors/turbo will do around 270-280 anyhows (injectors more if required)

[ash_uk2000]

ok so would u recomend fuel pump and bigger top mount, i want it to be reliable but enough poke

[ash_uk2000]

the coilpack is to the side it also has blue hoses were those black ones was in the pic

[Scott.T]

Originally Posted by ash_uk2000

the coilpack is to the side it also has blue hoses were those black ones was in the pic

It's a MY99 then, registered probably late 1998
I would advise you check those hosed, if replaced with blue ones to be sure you have the restrictor in place.

You may find there in no restrictor in Hose Number 2 and hence you are running very low boost and with the decat the ECU is struggling to control/understand whats going on.

You really need to get a boost gauge on their, even if only temporary to see what it's doing. Their easy to fit as you will have a spare port to plug onto just infront of the throttle assembly (i't scurrently capped off).

[ash_uk2000]

yea i want one permenant but just got car so if anyone has one cheap pm me please also ill were can i get that pipe?

[ash_uk2000]

number 2 is a standard hose is that were it is?

[Scott.T]

Originally Posted by ash_uk2000

number 2 is a standard hose is that were it is?

yes, if you squeeze it you should feel a lump in the middle

boost gauges off ebay can be had for about £20
some come with hose, if not u can use washer hose for a few quid from halfords. This should get you going.

[bonner]

Hi ash i have a boost gauge u can have for free! its nothing special but will do the job till u get somthing betta but u will need a 52mm pod

[ash_uk2000]

great cheers can u pm ya num will sort out picking it up asap!

think i have found my problem its got two chunks out of two of the leads as my mate had a look a previous scoob owner and drove it and missed slightly so gettin 10mm leads and new plugs hopefully this sorts it as the leads look like they been stabbed with a screw driver! and look well past it i got heat 7 plugs should they be better