R33 Series 1 Turbo Lag?

[bunta08]

ok so i have a series 1 r33 gts-t with fmic, full 3" zorst, new 0.8mm plugs and new spitfire coils. i recently installed a aftermarket boost gauge and realised that my car was running about 14 psi with that standard turbo so i turned down the manual boost controller so it was running the stock boost again but now the boost guage doesnt start reading 7psi till it hits about 5500rpm where as when it was on 14psi it would hit about 11psi at 4000rpm. also when i change gear it takes alot longer to come back onto boost as well

what could be causing it so spool so much slower on just the stock boost level?

[SargeRX8]

Get your boost controller out of there, with a full exhaust your car should not boost more than 10psi. Those are 7psi actuators and with an aftermarket dump pipe should see them run between 9 - 10psi. You use a boost controller to RAISE boost, not lower boost. You cannot lower boost below the actuator spring level. To get the lowest possible boost you can out of your turbo and actuator setup, run no boost controller. I always had my boost controller off with my old setup, even at 1% would see it on 10psi. No boost controller generally saw 8psi on my series 2 r33 stock turbo and actuator.

[bunta08]

ok i did what you said to do but yet it still does the exact same thing as before like not spooling up quickly, also there is alot less induction noise then before

[GTSBoy]

Question. Is the manual boost controller that you took out a gated one? If it is, then the boost controller was preventing any pressure from being applied to the wastegate until some given pressure (let's say that it was 70% of the boost pressure setting). When you turn it down what happens is that the 70% of boost setting is now a lower number and the wastegate gets pressure at lower boost and so it creeps open and spools more slowly. Or if you remove the boost controller, the wastegate starts to see boost pressure right from zero and will creep open even earlier.

Now, ordinarily this should not be a problem. A gated controller will give you snappier boost response, but it is important to remember that from the factory there was no such thing installed and from the factory the car would make boost at a reasonable engine speed - certainly making boost from less than 3000rpm and on full boost by 3500 rpm. The accuracy of those rev numbers doesn't matter, here - all that matters is that they are much much lower than 5500rpm.

So if your engine was taking until 4000rpm to make 11 psi with the controller wound up to 14psi and is now taking >5000 rpm to make any reasonable boost at all, it implies that there is a severe problem and that the boost controller was masking it for you. Not very well, because 4000rpm is pretty bloody laggy for a standard turbo.

I'd be looking for all the usual suspects. Blocked or collapsed cat converter, rag in the intercooler piping, damaged blades on the turbine (just in case that is possible without it shaking itself to pieces), damaged blades on the compressor, turbo intake pipe gone all soft and collapsing on you, massively dirty air filter (or otherwise shit filter that flows so poorly that it shouldn't even be used on a Lancer), etc etc etc.

[89CAL]

Even 4000rpm for 11psi on a stock turbo seems way to laggy. I'm hitting 18psi with my HKS turbo before then.

As GTSBoy said, check your piping, suction and pressure sides, pull them all off if you have to just to be sure. Check the rubbers/silicon joiners for cracks etc, taking special note of the ones that you've touched recently. Filter, especially if it's in the standard airbox as it's not visible when you open the bonnet

Also when you've done all that id try an ECU reset in case it's gone a bit crazy.

Does the car idle fine? Is it shooting out any smoke when you load it up (boost)? Any other info you can think of?

[bunta08]

ok so i have checked everyting, no pipes are loose, replaced the pipe that goes from the afm to the turbo with a metal one so it doesnt colapse, checked the cat to see if its colapsed and it turns out its just a decat pipe with a cat sheild around it and cleaned the filter

the car idles fine and doesnt miss a beat at all and there is no smoke when i put my foot down either

i replaced the actuator with the one from my r32 that was on 10psi to see if that was the problem but now its spooling to 16psi @ 6000rpm

how do i go about resetting the ecu?

[GTSBoy]

Restting the ECU is done by disconnecting the battery and then putting your foot on the brake or turn on the headlights or something that will make sure there's no residual power stored on a capacitor somewhere. Leave it like that for a while, then power it back up.

Did you look at the compresor wheel while you had the inlet pipe off?

[BOOZTJUNKEY]

Possibly a faulty wastegate or dump pipe ?

Waste gate flap is getting stuck shut because of a poorly made dump pipe or is stuck open slightly meaning it's not bleeding enough pressure

Possibly a cracked dump or turbo housing HIGHLY UNLIKELY BUT stranger things happen lol

[bunta08]

ok ill reset the ecu when i get home from work and see if that helps with anything and yes i did have a look at the compressor wheel while the pipe was off and the blades are all fine and there is no play at all

i will also check the waste gate to see if thats opening or closing the whole way as well but it just doesnt make sence to me as to why it would spool up so much quicker with the manual boost controller in

thanks for the help guys

[GTSBoy]

it just doesnt make sence to me as to why it would spool up so much quicker with the manual boost controller in

I told you why in my first reply.

[89CAL]

^This

But if you want it explained again:

Without a boost controller, actuator see's 1psi, 2psi etc till it reaches a certain point where it will hold boost constant

With a boost controller, your actuator see's 0psi until there is enough pressure to open the boost controller (cracking point) in which point your actuator see's 7psi for example immediatly. The wastegate opens quicker to hold boost at that point. If you have a boost controller set above the actuator then you will find the boost controller will open and close rapidly to keep the desired amount of boost in the system.

It's similar to a relief valve on a hydraulic system, if you have any hydraulic knowledge

[bunta08]

ok so i checked the waste gate and apperently it was stuck shut so that explains the over boosting problem but i still get that slow spool but i guess that means that there would hae to be a leak somewhere right ?

[GTSBoy]

Now you have to wonder how healthy the ceramic turbine is (although it's hard to image that it is partially stuffed). Otherwise some sort of exhaust leak would be a leading candidate for slow spool.

Edited September 14, 2011 by GTSBoy

[bunta08]

well i took it to my mechanic around the corner from my work and he says that the gasket where the top of the inlet manifold joins to the bottom of the inlet manifold is pretty much gone so im gonna replace that tomorrow and see if thats where it is loosing presure from

also there shouldnt be any leaks on the exhaust side of the engine as i have just had the manifold machined, new mls gasket and all new studs/nuts. well atleast id hope there is no leak

Edited September 14, 2011 by bunta08