19 replies to this topic

[cdn99gtb]

Hey I was wondering if you all could help me out, there is a shop here saying that tt engines tend to have bearing and secondary turbo

failures is that true ? thanks.

[cdn99gtb]

So they were true oh well good thing I really like this car  . So if I am correct stay on top of maintenance and don't overly abuse her and she'll

be ok ?

[CRUISN]

Pretty much its all about how you treat it.

[cdn99gtb]

I hear ya on that.

[cdn99gtb]

Free flowing how do you mean, from down pipe and back or catback ?

[Jimbo]

Oversized dumps will kill primaries. Some people seem to think you can just smash a 3" on it. 

A dump pipe of 2" to max 2.5" is ample. The turbine outlet size is tiny, about 1.5" if that. Too a big exhaust and they will spool themselves to death. I ran 2.5" dumps to a 3" mid section and free flowing Fujitsubo muffler on my Gen2 GT-B. The TT is naturally more quiet than a single turbo anyway but they sound great on full song.

[cdn99gtb]

Good to know, the most I am thinking of doing is just a nice catback, any suggestions.

[TSG]

Don't be scared to let it run through the rev range though, I've heard of secondary turbo's failing simply because they never get used just change the oil every 5000km and high octane fuels (100 RON for a JDM GTB I guess?). That should keep it from big end damage. Listen out for pinging under load. Mine did it once, it was a cheap air filter suffocating the motor, so use genuine or better there and clean the MAF sensor when you swap it out too. But other than the TT stuff (that shouldn't need to be touched unless its not working properly) its just regular turbo Subaru maintenance to keep it happy.

 

I've found my car to be very reliable. Don't drive it like you're competing in a rally stage every day and you should be fine. I dare say Canadian conditions would be easier on the TT than what we deal with.

[cdn99gtb]

I have her stored in the garage for the winters(salt and gravel) they put on the roads would eat the body to nothing before too long. And I put the highest grade

of fuel here 94 octane not sure what that is in RON ?. And I don't abuse her, have not heard any pinging at all.

[Liberty]

I don't know much about fuel measurements and ratings from overseas, but I did manage to find this:

 

In most countries, including Australia, New Zealand and all of those in Europe,^{[citation needed]} the "headline" octane rating shown on the pump is the RON, but in Canada, the United States, Brazil, and some other countries, the headline number is the average of the RON and the MON, called the Anti-Knock Index (AKI), and often written on pumps as (R+M)/2). It may also sometimes be called the Posted Octane Number (PON).

Difference between RON, MON, and AKI

Because of the 8 to 12 octane number difference between RON and MON noted above, the AKI shown in Canada and the United States is 4 to 6 octane numbers lower than elsewhere in the world for the same fuel. This difference between RON and MON is known as the fuel's Sensitivity,^[4] and is not typically published for those countries that use the Anti-Knock Index labelling system.

 

Australia is the same as Europe in its octane and RON figure. BP Ultimate 98 for example is 98 RON.

[cdn99gtb]

Doesn't living in higher elevations have an effect on octane and pinging ?

[Morgan]

I don't think octane is affected by elevation, rather the breathability of your engine.

 

Less air at higher elevations = suffocation.

 

Could be wrong?

[aekOne]

Yeah I've not heard of altitude being an issue with fuel octane. Unless your at an extreme altitude (say the moon) id have thought your ecu would be able to compensate for most air density situations.

[cdn99gtb]

So I guess or 94 octane must be ok for fuel but then again I have only pushed the car a few times and did not hear anything. Is the pinging very loud when it happens ? I have heard it on domestic cars here but not a JDM import car. Sorry about the silly questions but just want to make sure seeing we don't have these cars here.

[Morgan]

I'd only use 98 for the GT-B

[alexGT]

So I guess or 94 octane must be ok for fuel but then again I have only pushed the car a few times and did not hear anything. Is the pinging very loud when it happens ? I have heard it on domestic cars here but not a JDM import car. Sorry about the silly questions but just want to make sure seeing we don't have these cars here.

 

that fuel will be fine. higher elevation means the air is less dense which can affect mixtures but thats what the o2 sensor is for

[duncanm]

US: (RON+MON)/2) 94 == AUS: RON 98

 

Canada uses the (RON+MON)/2 system (says wiki, anyway). So your 94 is equivalent to the Australian 98

 

Octane is not affected by altitude - its a property of the fuel.

 

Carb'd engines may ping at altitude due to the thinner air messing up the AFRs..  but the MAF sensor and fuel/timing maps in your injected engine should be able to take care of most situations.

 

Turbos are also less affected by altitude, as they can control manifold pressure with boost (though I'm not sure if the Subaru boost control is absolute or relative to atmospheric pressure -- anyone know?)

[cdn99gtb]

Sweet thanks everyone.