legacycentral bbs

how is it that the overseas spec 1st gen legacy turbo puts out just over 200 hp stock? Its only a 2 liter engine also. Is the turbo that much bigger? Cause stock it only runs 10 psi. Whereas our US/Canadian spec have the 2.2 and run 9 pounds and only have 160 hp . Mmmm, anyone know how?

Thanks,
Mark

higher flowing heads
Bigger turbo
intercooled

a few of the differences that add up to a more efficient engine.

-Jason

What did they get as a turbo? Wasn't it also an IHI?

Mark,

The turbo is an IHI RHB5 I believe, i'm not sure, but I live in Sweden and I have got a 200hp Legacy...

I will check tomorrow what turbo it is...

//Mattias

Check out my Subaru at:
http://surf.to/jbs_racing/

Observe! the page is in swedish, you will have to click on Bilder, then Bilar, then Mattias Bilar, there it is...

my imported JDM motor has a VF10.
im sure the ecu tuning is slightly better too.
noah

An IHI VF10 is the exact same thing as a IHI RHB5. the 2.0 liter has a higher redline, air/water ic, more boost pressure, etc....

LegacyT wrote:how is it that the overseas spec 1st gen legacy turbo puts out just over 200 hp stock? Its only a 2 liter engine also. Is the turbo that much bigger? Cause stock it only runs 10 psi. Whereas our US/Canadian spec have the 2.2 and run 9 pounds and only have 160 hp . Mmmm, anyone know how?

Thanks,
Mark

Another reason is fuel - In Japan 100 octane is available which helps performance.

read posts below " liberty engines"
Mark

I don't know how the Japs rate the Octane, there are two different ways. One of them is a higher number and the US uses the average of the two. So it could be a higher number but not any better....

I do know cars exported from Japan for sale as new cars for the Australian market are detuned for the local fuel.

In New Zealand where alot of J-Spec Subaru's have been imported they use 96 and 98 octane which is for sale at the local gas station.

This may be common knowledge, but it was new to me. This link may help clear up what RON rating you are seeing with pump gas (in Austrailia)
http://www.powerchipgroup.com/articles/ ... 20one.html

For those of us in the USA... From what I have heard, "In the United States, Federal Law requires that gasoline octane ratings be posted on the pumps. The octane rating shown is an average of Research Octane Number (RON) and Motor Octane Number (MON). This number is also referred to as the anti-knock index (AKI) or Average Octane Number (AON)."
So for the "Regular" 87 AKI rated gas has a RON of 91, "Mid-grade" 89 AKI would be 93 RON, 'Premium' 91 AKI rated gas has a 95 RON, and around me there is even 93 AKI rated gas which has a rating of 98 RON.

So I guess that those cars from Japan that are tuned for 100 RON would need to be detuned a little for us to run them safely.
Noah

The EJ20G engine, at least as fitted to Jap. 91-92 Legacy GT and RS's needs only 95 RON octane.

The reason they are more powerful is emissions - not as strict in japan in the early 90s as in the US.

Later Legacys (Gen3) require 98 or even 100 RON but these are japan only models, except as pointed out certain detuned models exported to Oz.

Better heads. DOHC.
Intercooled.
More boost.

That's all it takes.

Heads: flow = power. better heads = flow = power.

Boost: I know how much better my car feels at around 10 PSI than the 8.7 she runs stock.

Intercooled: every 10 degrees raise in temperature is about 1 HP lost. in addition, timing gets pulled due to a very hot intake charge. anything past 5-6 PSI really should have an intercooler. So intercooler means cooler intake charge, and more headspace for advanced timing.

Does anyone know whats the highest safe boost on the JDM BC5 engine?

Ben

EJ20impreza: "Regular" 87 AKI rated gas has a RON of 91

That is not entirely correct. The ratings arent static, the 87 could have a higher or lower RON and MON averaged to the same number. In other words gas with the same octane rating in the us will not always perform equally.