R33 Just Wont Run Right, Need Constructive Help

[KiwiRS4T]

I think its a cr*p turbo base on a quick google. It seems it is too small to make the power you are looking for. If it is not your daily you could take the turbo off and send it to Hypergear and see if he can do anything with it, If not he will not waste your money but tell you so.

[GTSBoy]

One other possible cause of det and/or false detection of det and/or wiggly power curves. OK, actually two reasons.

1) It's an old motor. It might be moving enough oil around under boost to cause octane reduction and hence detonation. I know you said it doesn't use much and doesn't blow smoke, but realistically you can't see the oil smoke for the black fuel smoke under boost anyway (there's enough black at 11.5-12:1 to mask enough blue to cause det). Do a compression test and perhaps a leakdown test. They're not actually great tests for seeing if the oil control rings are not working properly (because they test the compression rings!!) but they can be indicative of wear.

2) Valve float. Again, old engine + more boost can make the valves float and this can be both noisy (and therefore give false knock readings) and will cause wiggly power curves.

[scotty nm35]

But the biggest concern we had was the power began to oscillate quite violently once we reach full power, this could be seen and felt, we noticed as we turned the boost down the oscillation smoothed out.

That sounds like on boost surge, not something you want happening ever. I suspect the turbo wouldn't last 3 laps.

Make sure you tell Tao you plan to track it when you ring Hypergear.

[XKLABA]

So the boost line on the dyno graph spikes 2 psi then sits flat yeah ?

I'd go with the valve float theory for your wavey power graph

What plug gap are you running, 0.7mm ?

[Pete K]

So the boost line on the dyno graph spikes 2 psi then sits flat yeah ?

I'd go with the valve float theory for your wavey power graph

What plug gap are you running, 0.7mm ?

Im currently running 0.7 or .8 i think just the standard gap not the 1.1's, i just the cheap copper ones. i cant remember the number at the moment, how does one prove its valve float? and whats involved in correcting it?

Im wondering if its worth buying a low km used engine or just working with what ive got. but i guess there is no real way of knowing the next motor would be any better

[scotty nm35]

Changing your good engine to get around buying a decent turbo seems somehow backwards...

[Pete K]

Changing your good engine to get around buying a decent turbo seems somehow backwards...

I have no issues buying another turbo, but am a little concerned if it doesnt fix the issues i then need perhaps a head rebuild, or somthing more significant. 225k+ on a motor that im guessing has had a hard life, im thinking everything may be worn out and rather then a costly complete rebuild a low mileage motor might do the trick,

[scotty nm35]

There are usually tell tale signs of engine damage, knocking, ticking, usually noises that come from high mileage or poorly serviced engines. If it all sounds good and you have fresh oil in it, why not lean on it until it blows, then buy a new engine if you need one.

[Blackkers]

There are usually tell tale signs of engine damage, knocking, ticking, usually noises that come from high mileage or poorly serviced engines. If it all sounds good and you have fresh oil in it, why not lean on it until it blows, then buy a new engine if you need one.

This is good advice. If 2nd hand motors are cheap enough then you won't cry when it explodes so push it!

Buy a good turbo first

[Pete K]

the motor sounds really good and does run along nice which is why i bought it, ill ring hypergear today and see what we can do about another turbo, i can always transplant it after all if the motor dies

[Ben C34]

You will be very happy with a new turbo!

[MrStabby]

One other possible cause of det and/or false detection of det and/or wiggly power curves. OK, actually two reasons.

1) It's an old motor. It might be moving enough oil around under boost to cause octane reduction and hence detonation. I know you said it doesn't use much and doesn't blow smoke, but realistically you can't see the oil smoke for the black fuel smoke under boost anyway (there's enough black at 11.5-12:1 to mask enough blue to cause det).

Could he disconnect the PCV hose, plug up the intake side so it doesn't suck air, and just let the cam cover side vent to atmosphere for a dyno run to see what happens as a quick and nasty alternative to those tests?

[Pete K]

Well had a good day today, removed the existing turbo which was good timing as all the hoses connecting it were about to fail, water line split and drained the radiator for me which was fun, one down side for having your own hoist is you can stand under stuff as it leaks , I spent a fair bit of time talking to Stao today from hypergear, he is very confident my issues are from a shit turbo where the exhaust housing is to small for the compressor, he recommended high flowing my turbo or getting another. After telling him what i wanted he advised me to go for an ATR43ss1PU with a .86 turbine and an 18psi actuator and i wont be using any boost control.

im exited by the prospect of getting the turbo but im really nervous about running 18psi in a car that has had constant issues running 14 and 16psi. im worried with an 18psi actuator i wont be able to wind the boost down to reduce detonation. Stao is confident that i can manage this by reducing the timing to allow for the extra boost, I dont doubt what he is say is doable but i have not though of or heard of this before, Is this a common way to tune,

[KiwiRS4T]

18psi is nothing. Its all in the tune. High PSI are only a problem with stock turbos because of the limitations of the turbo.

[Ben C34]

Get excited!

[simpletool]

Don't place so much concern in intake pressure. It's only a measure of flow restriction (almost certainly caused by the turbo itself).

[discopotato03]

Does your car have the original coils in it ?

A .

[Pete K]

Does your car have the original coils in it ?

A .Hi , yes it has factory coils, they appear to be in good condition, ive never had any issues. cheers

[JJEkoms]

Easy peice of advice. Use a better tuner. If your tuner was any good you would know the answers your looking for..

And yeh those turbs are a nasty $350 buk ebay job arnt they?

[Pete K]

Easy peice of advice. Use a better tuner. If your tuner was any good you would know the answers your looking for..

And yeh those turbs are a nasty $350 buk ebay job arnt they?

My tuner is fine, he said right from the start that he really had his doubts about the turbo, but seeing as im on a limited budget we were just trying to make what i had reliable. the problem is every time the car starts to perform we had these issues. New turbo should arrive in the next week or so and we can see what happens