Overboost 1.7bar on GSR?

[ftzone]

Dear Sifu,

I recently did a top overhaul on my stock 4G93T engine.
My mech used the 4G93 NA metal gasket on my engine.. so this is what happened.


Pros
1. Very Good Pick-Up & Acceleration.
2. Car feels a lot lighter and good responds at low end to mid-range RPM.

Cons
1. Overboost - 1.7bar...
2. Engine Knock at high boost - a potential blown engine in near future.


How can I fix this problem?? Suggestions from my mates are;
1. Installing an external wastegate - (but TD04L is too small for ext.wastegate)
2. Installing Electronic Boost Controller - (AVCR - damn expensive)
3. Installing Additional Injector and Controller for sufficient fuel to prevent detonation.
4. Installing Bigger Turbine to Lower the Boost.
5. Do not hit full throttle......


So what can be the best solution for my problem?? Any ideas? Can the Ext.Wastegate solve my overboost problem? Anyone used the Nitro Wastegate? I heard it tends to leak. If possible I would love to have the cheapest alternative.



Thanks in advance for sincere help from u guys in ZTH.

 

[monsterv6]

why not u lower down your level of boost by installing at boost controller..?

 

[HanafyEG]

overboost does it because of the na metal gasket? high compression right? because of the compression the fuel and air burn before the spark plug ignite..so cause detonation..dangerous..hehe:)

 

[Itab]

metal gasket differs only in thickness la....NA or turbo also same mah,thicker lower compression=can boost higher,thinner higher compression so cannot boost so high lo.i got fren using the metal gasket tht i sold to him,brand new mitsu one 1.5mm on his gti 4G93P,set his cams with adjustable cam pulleys no problem also.tht fella planning to put in his nos kit somemore...me using the same 1.5mm metal gasket on my gsr also

juz my opinion :) hope it helps

 

[jinkl]

1.7bar is overkill for a gsr
is also overkill for a evo itself man
get a external wastegate
no boost controller needed
get the correct psi spring
get tial 1bar wastegate , and u r good to go la

 

[speedz1665]

ftzone,

i believe because ur mech used the NA gasket, the compression has increased as such ur boost increase as well your accelaration and pickup.

I think u should either reduce ur compression or reduce boost if not ur gonna have a blown engine , broken conrods or pistons.

Best to get a metal gasket 1.0 mm and above or reduce boost level (what boost controller u using now)...if stock check whether ur actuator is ok or not..sometimes actuator jam can cause overboost..

speedz

 

[szekeiemme]

wait for my fren turbonetic reply.. his gsr.. 1.9 max boost.. heheh

 

[jinkl]

1.9bar
sure not got something one :D
atleast fuel pump , regulator , piggyback , metal gasket rite bro
if not sure silap hari will kaboom

 

[ftzone]

hmm... guys.. i suspect actuator assembly got sumthing wrong also.. perhaps the wrong hoses connection.. bla bla bla... in fact got another GSR using the same metal gasket as me.. only get 1.2bar... just nice ler... but mine never ending boost... sigh..
will an external wastegate really solve this problem? changing another head gasket is NOT an option.

So the verdict is either an external wastegate or apexi AVCR boost controller... which one?

 

[turbonetics]

yes...last time my gsr running 1.7 stock...without having any prob..engine stock..stock evo2 fuel tank...and im using gsr rs ECU...once my max boost are 1.9..drive it everyday for a year without having any prob...maybe lucky?

 

[speedz1665]

ftzone,

y dont u change the actuator..i think around 100 bucks only..i suspect ur actuator not opening properly..

 

[Joeker]

yes...last time my gsr running 1.7 stock...without having any prob..engine stock..stock evo2 fuel tank...and im using gsr rs ECU...once my max boost are 1.9..drive it everyday for a year without having any prob...maybe lucky?

1.9 bar boost was the peak hold reading from your turbo timer's built in boost meter rite?

Was the turbo timer bought brand new or from chop shop?

Have u calibrated or control check the timer's reading with a control boost gauge?

 

[monsterv6]

1.9 bar boost was the peak hold reading from your turbo timer's built in boost meter rite?

Was the turbo timer bought brand new or from chop shop?

Have u calibrated or control check the timer's reading with a control boost gauge?

i think have a gause problem la...

 

[monsterv6]

gauge i mean

 

[Joeker]

Ftzone

Wat is the gasket mm?.

U are overboosting severely and u cannot solve it by adding boost controller nor wastegate.

U have to look at compression and fueling.

I think High Compression and High boost pressure is a recipe for disaster.

 

[turbonetics]

i'm using blitz dual timer...means im using digital boost meter...yes...1.9 was the peak...some ppl said tht timer wasnt accurate...i did ask some of my frens...they said it is accurate..after the peak...boost starting to drop till 1.5 -1.7

 

[Joeker]

Have u considered borrow your fren boost meter and check whether the reading from the timer is accurate or not?

U can easily "T" at any vacumn hose at the intake manifold to hook up a remote boost meter to check.

1.9 bar is very extremely hi and on stock tD04 turbo is overkill. U are not making any more power and possibly the other way around.

Better check the boost pressure reading.

 

[ftzone]

Ftzone

Wat is the gasket mm?.

U are overboosting severely and u cannot solve it by adding boost controller nor wastegate.

U have to look at compression and fueling.

I think High Compression and High boost pressure is a recipe for disaster.

Joeker bro.. u sure AVCR nor ext. Wastegate will not solve my problem? thats sad man... the gasket should be standard mm for the 4G93P engine. Changing the gasket again will cost me a bomb. I'm going to die.

 

[jinkl]

errr the topic going somewhere else redi

bro ur actuator jam just like mine i guess
ur boost climbing non stop means ur internal wastegate (actuator) already jam
nothing to do with ur metal gasket
one more could be one of ur vacuum hose sudah koyak
check on both of tht
if internal wastegate rosak
just go chop shop and get another actuator
if u want more umphhhh then get a external wastegate.

 

[turbonetics]

joeker....i did ask my foreman last time...he said is accurate..he used to set to 1.2bar for me...by using tulang ikan..when drag tht time...i will open one or two more..1.9 only spike...or maybe i lucky la..hehe