Jump to content
SAU Community

Recommended Posts

hey guys my HKS 2530 is now installed and running. the problem i have now it the turbo is running to much boost! and as i dont have a boost controller i dont know what 2 do.. i noticed this when i was in 4th gear flat the car cut out.. cuz i hit the fuel cut. at about 1 bar. cuz this be the actuator?

Link to comment
https://www.sau.com.au/forums/topic/146864-to-much-boost-help/
Share on other sites

do you have an aftermarket boost gauge?

the "boost cut" isn't a boost cut. it isn't determined by boost pressure but by airflow.

if it got to 14psi then it could be that it has a 14psi wastegate on the new turbo. if it is still the stock wastegate and you have an aftermarket gauge then i'd say there is something blocking it slightly.

but it is more than likely aftermarket ecu time.

BTW, if you don't have an aftermarket gauge, but have a bigger turbo you are an idiot.

thanks for your comment mad082. but i have an after market boost gage if you took the time to read my post i did say i was hitting 1bar.

iv just been told the turbo had a standard RB25 actuator from the person i brought it from. the turbo was installed by myself.

bumb still havibng problems any 1?

Isn't the standard actuator a 7-8psi actuator? probably try buying a new one thats rated at 7psi or something along those lines, (only around $80-$90) or a genuine hks actuator to suit your turbo, i purchased a 14psi heavy duty type (or whatever they're called) and my turbo was overboosting cos the wastegate hole on the exhaust housing was too small to get rid of the gasses in effect creating more boost, but i dunno if thats your problem, i had to have my exhaust housing wastegate hole thing ported out, its fine now, and they adjusted the actuator and its not budging of 6psi.

Make sure the actuator is fully opening manually and make sure the little flap that covers the wastegate hole on the exhaust housing isnt hitting anything whilst trying to open, i know how you feel with this problem cos i've been through it aswell but its strongly advised if you have a larger turbo and standard ecu turn the boost down... to bare minimum.

the stock r32 wastegate actuator is 10psi.

what actuator is being used? if it is the stock one, it may not be complatible with the turbo. it may be moving the correct distance, but it is starting in the wrong spot so it is only opening half way.

Probably try taking your dump pipe off and see where it starts and how far manually it can open, but i dont think you can adjust a standard wastegate can you? hhmm... another thing i noticed with my issue was that if you had a actuator rated at say 10psi it wouldn't be boosting over that, but if it cant let the gasses escape through the wastegate hole at the back of the turbo then it'll overboost. Also if your catalytic converter is blocked with crap it'll overboost aswell as it cant let the gasses escape.

All honesty try buy the wastegate suited to this turbo or just get another actuator thats adjustable, OR external wastegate will solve all your issues in one hit, just a bit more expensive.

Edited by R33HVN

Probably dude the best thing for you to do is to take the dump pipe off and check that the actuator opens that lil flap on the back of the turbo all the way, then to make sure that the flap isn't hitting anything when trying fully open, but sometimes different cars produce different amounts of gasses, my turbo's wastegate hole had to be ported but another r33 with the same turbo didnt... its weird but makes sense lol

Also what sort of a cat do you have? I was also told that if its blocked with sh!t it can cause overboosting, but if you can find out exactly what psi the standard wastegate should open at that would be helpful and test it with air pressure to see when it fully opens and if its functioning correctly.

You just have to do the process of elimination, first eliminate its not the cat (unless yours is gutted then its not that), another thing then is the wastegate actuator, the last thing is porting the turbo. But easiest solution if its not your cat is a ext wastegate which will work A1 but just more costly. If you were to get a boost controller now it wont decrease the amount of psi cos its up2 the actuator to do that. B4 you buy just test the actuator.

Good luck dude i feel your pain!

i dont have a cat so it cant be that.

i have a split front\dump pipe to straight though, front mount intercooler, bosh 040 fuel pump,

the car will be tuned later on when my injecters and new AFM arive. but i would like to fix this problem before it goes to get tuned!

i dont have a cat so it cant be that.

i have a split front\dump pipe to straight though, front mount intercooler, bosh 040 fuel pump,

the car will be tuned later on when my injecters and new AFM arive. but i would like to fix this problem before it goes to get tuned!

you know how your dump pipe is split therefore 2 pipes on the flange coming off turning into 1, sometimes the smaller pipe which comes off the wastegate part of the turbo on the dump pipe is actually hard up against or very near the actual housing, its hard to explain but a picture is worth a thousand words, let me find one and i'll edit the post and show ya what i mean cos that "could." be causing it to overboost and not let the flap open up all the way.

what sort of dump pipe do you have if its an ebay special i can tell you that its most likely fouling on your wastegate flapper and not allowing it to open i had this happen to me either way whip the dump pipe off and see if can see any marks were the flapper may be hitting. as well check the usuals splits in hoses and that they are connected properly and maybe try wacking on the rb20 actuator as the 25 one may just be stuffed. i have also heard of people using a bashed out cat which actually creates more of a a restriction as it causes alot of turbulance in the hollow housing. i had this same problem but in the end it turned out i had a lot of none standard 25 gear in my engine which created alot more gas to try and get rid of thorugh a stock turbo

no i dont have any pictures sorry. i brought the dump pipe from BATMBL on this webpage.he told me there shouldnt be a problem.. =( i tryed moving the actuator i can move it slightly but its very hard to move. same with the RB20 actuator.

i should take it off and have a look just dont have any time today? could it be anything eles?

no i dont have any pictures sorry. i brought the dump pipe from BATMBL on this webpage.he told me there shouldnt be a problem.. =( i tryed moving the actuator i can move it slightly but its very hard to move. same with the RB20 actuator.

i should take it off and have a look just dont have any time today? could it be anything eles?

Thats the first thing to look for honestly if you got no cat, if its opening fine and not fouling then the dump pipe should be ok, then next thing is the actuator itself, i'm pretty sure the rb25det ones are only meant to open around 7-8psi... but the heavy duty one i have is adjustable and you can regulate the boost pressure via the wastegate without a boost controller, but you get the controller to keep the boost steady.

Best bet is to take the dump pipe off and investigate a bit, have a look at the flap that covers the wastegate hole and if the flap is overlapping alot of the hole or wether the hole looks a little small, but gt25 is a t25/28 rear housing? might need to be ported if everything else is ok dude, mine had to be ported cos its more or less designed for 4 cyls, cant let gasses escape quick enough therefore creating more boost than it should be.. you got nothing to loose dude the only thing thats gona sort this out is patience otherwise take it to a tuner and get em to sus it out for ya... but if the turbo needs to come off theres alot of R&R you gota pay for which sucks balls...

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • It is a kunfine Android screen . Does anyone know the wirering diagram of the fuga ??
    • just an update to this, poor man pays twice  Tried sanding down the pulleys but it didnt do the trick. Chucked another second hand alternator in the na car which I got for free off my mate and its fixed the squelling. Must have been unlucky with the bearings.    As for my turbo car, I managed to pick up a cwc rb alternator conversion bracket + LS alternator for 250 off marketplace, looked to be in really good nick. Installed it , started the car and its not charging the battery.... ( Im not good with auto elec stuff so im not sure if this was all I needed to do but I verified such by using a multimeter on the battery when the engine was running and I was only getting 12.2v )   I had to modify the earth strap for the new LS alternator , factory earth strap was a 10mm bolt which did not fit the bolt on the LS alternator which was double the size so I cut it off , went to repco bought some ring terminals that fit, crimped it onto the old earth strap and bolted it up to the alternator , started the car and same issue. Ran like shit and was reading 12.2 at the battery.  For a "plug and play" advertised kit thats not very plug and play but alas.  My question is , am I missing something ? Ive been reading that some people recommend upgrading the stock 80 amp alternator fuse to a 140 amp but I dont see how that would stop the alternator charging especially at idle not under load.  Regardless ive pulled it out and am going to get it bench tested by an auto elec tomorrow but it would be handy to know if ive missed something silly or have done something wrong.   
    • My wild guess is that you have popped off an intake pipe....check all of the hoses between the turbo and the throttle for splits or loose clamps.
    • Awesome, thanks for sharing!
    • To provide more specific help, more information is needed. What Android screen? What is its wiring diagram? Does the car's wiring have power at any required BAT and ACC wires, and is the loom's earth good?
×
×
  • Create New...