What Am I Missing?

[jagor33]

So I brought a IBC-R so I could set the boost as I want etc...

I replaced the hks actuator for the stock one I removed last year and thought I would check it was holding 0.4bar as its meant to,
Its not.. its going anywhere from 0.5 to 0.8bar but only over 5k and if it don't go flat because of the over boosting/ R&R

my aim was to set the controller for slightly higher boost lower in the rev range and then backing off where the normal flat spot is on the stock ecu,

So the issues I have checked are:
fuel pump fitted before I got the car is actually what is in the tank. (also did the relay mod, pump is still quiet though for a walbro 255)
all pipes are tight and clips work (did find 2 that were dud)
check the pipe to the actuator is not split..

I have not got the original boost valve installed either.
I checked the fuelling and its around 12:1 until it gets over 4k and then if the boost goes over 0.6bar it drops to between 9 and 10:1
consult is also showing fuelling going up and timing coming out on the data log if it goes higher on the boost.
I have removed and re-soldered the AFM also cleaned it.
I have removed and re lacquered the coils
set the spark plugs to 0.8mm
changed the oe bov to high boost mode

checked the ignition is 15btdc - even though she is a lot better at 20btdc around town

The mods I have are:
HKS exhaust+ de-cat+ down pipe
R34 SMIC
HKS panel air filter
cometic head gasket (1.3mm)
large fuel filter
walbro 255 pump

oh and she is still auto so cant remap (I think)

example:

went to get fuel 15miles each way,

on the way to get fuel she would hold 0.4bar unit near 5k then it would go up to 0.6-0.7bar

just after leaving left the fuel station I joined the main road and she held 0.4bar all the way up and went very nicely, however I went to repeat it and it went up to 0.8 and naturally went flat.

I have done a few searches on here, hence the pump relay mod, bov mod, lacquering coils and the plug gaps. this site is a very good resource :-)

[Ben C34]

Welcome to the forum!

Have you checked the waste gate flap isn't sticking? Disconnect it from the actuator and move it by hand.

What do you mean changed the oe bov to high boost mode?

Also, walbro pumps are heaps quiet

[jagor33]

Hi yeah I have had the turbo off and checked the whole thing. As I was finding another issue,

High boost mode as per the DIY thread is to drill the feed line to the base of the diagram so it open and then block the hole where it joins the J pipe,

Glad the pump is known to be quiet though:-)

[jagor33]

After a lot if playing and trying things it's related to ign timing, I retarded it more and it got worse. I then set it to where it was when I brought the car and it perfect. But I now have det above 6k or at leased a noise from the exhaust side of the engine like it's coming from the passengers foot well. Might change the auto fluid to make sure it's not old fluid around the clutch packs etc. But a happy result.

The boost is now 0.4bar and stable all the way up

[scotty nm35]

Timing needs to be set correctly, and high octane fuel used, just retarding the timing to use lower octane will result in overboost, as the fuel is burning in the turbo.

[jagor33]

the timing was well out when I got the car, but I didn't spot it until after I lost pistons. I got a reasonable timing light to set the ignition timing to 15btdc, it then gave me a flat spot, but higher boost, so as a side thought I removed the hks actuator I had as it was sold to me as new but you never know type purchase, and put it back to stock with a view to installing the boost controller for the higher boost, even with the stock actuator I had more boost than I wanted, so I retarded the timing a little more and found the boost went up, I have now back to 15btdc and have a data log of the flat spot,

This is at 0.4bar boost with shell vpower.

rpm and ign timing are on the right scale, the timing is pulled from 4000rpm, and the VTC is turned off at 5700rpm according to the log file

This is a slow rolling start as shes auto

Edited March 26, 2014 by jagor33

[jagor33]

had a long play this weekend, found the loop for setting the timing wasn't agreeing with my strobe, and was seeing the wrong part of the signal, so I did a search and found others had this and use either on the coil feed or make a short HT lead, so as I wasn't home clipped on the feed and then set it to 15btdc, its a lot better and doesn't make any noises or fall flat, but is still pulling 0.6bar high up, it should be 0.4bar with the actuator.

I also changed the auto fluid and engine oil... that's made it nice and smooth too

[scotty nm35]

There are only so many times we can say to use cylinder one lead, not the shitty loop.

Sounds like your wastegate is too small to run such low boost. Wind it up, or better, weld it up.

[blue_vl_t]

0.4 bar is only like 5.8 psi, that is such a low setting. Two things, why are you running such low boost, and second, it's very hard to keep a turbo at that lower boost pressure. at the rpm of your engine rises, assuming you have an internal gate, the hole in the gate is only like the dice of a 10 or 20 c piece, so basically all of your engines exhaust flow must exit that hole so you won't spin the turbo any faster. I remember years ago when I had a volt turbo with a stock turbo with other mods, it would make 10 psi up in the rpm range even though the actuator was 7psi.

[jagor33]

I didn't understand the loop was so bad.. Either way loads happier now.

Well the plan was to use the original actuator for the low boost and then the boost controller for high (just before the power falls off because of other limiting issues) However it's the original turbo so I had assumed it would run low boost all day long,

It did hold 0.7-0.8 on the hks one ok though. I'll pop that one back on and see how she goes, all I'm after is stable boost before I put the controller into the system:-)

[Blackkers]

yeah its generally a better idea to run an actuator that is closer to your desired boost setting. Even if you have a decent boost controller

Edited March 31, 2014 by Blackkers

[jagor33]

fitted the hks actuator with 1/2 a hole tension, I am now getting 0.9bar at the top and 0.6bar by 4k, however she goes well.... :-)

[jagor33]

SORTED

Replaced the injectors/rail/fpr and filter - better off boost but still not perfect.

Replaced the fuel pump even though it had one 6 months before I got it.. The fuel line from the pump it self wasn't done up at all... And it's wasn't a walbro as in the history.. It was a denso 23 03G 3570 oh and the filter wasn't clean either:/

[jagor33]

Oh and before I did the injectors I went up to the local 1/4mile and did 14.7@101 I am now hoping to get a better time:-)