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2004 Forester XT
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6 Posts
Discussion Starter #1
Hey all,

I am new to the Forester community,
I just bought my 2004 FXT about a week ago.

Here are the current mods my engine has:

Catless up pipe (invidia)
Catback exhaust (hks)
AOS (grimmspeed)

The big caveat to my question here is that to my knowledge the engine has 250,000mi on it, I don't know if it has ever been rebuilt.

So my question for the community is what precautions should I take before doing any engine tuning? Should I go for an off the shelf tune or pay for a custom tune?

I don't really want to compromise the reliability of the engine, but I bought it to mod it so just want to be smart about how I do it.

Would it be smart to upgrade the stock intercooler or radiator?

Thanks in advance for any help
 

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2009 Forester XT
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636 Posts
Get a compression test, leak down test, and send an oil sample to a lab such as Blackstone. These will give you the best snap shot of the health of your motor.
If all is good, ensure all maintenance is up to date, specifically timing belt components, including water pump and idler pulleys. If you are unsure, assume it is not.
Pro tune is always better than off the shelf, and I'd seek the advice of a tuner concerning the mileage and things to be concerned about.

Sent from my E6910 using Tapatalk
 

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2001 Forester STi 6spd with MapDCCD
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4,642 Posts
X2 with what SkirbyKat said.


In years past i started to implement a mandatory 'Bill of health' if you will, on higher mileage vehicles before i started laying power into them in terms of tuning, especially if it has unknown history. This meant a compression / leakdown, smoke test and sending a sample out to be analyzed to make sure it wasnt swimming in bearing shavings. Even then, if stuff comes back okie-dokie, i still take it somewhat easy on blocks approaching 200k, or even over it. Been a pretty successful approach, but with high mileage comes more risk just due to age, regardless of good or bad results.

Seeing as it is old(er) i always recommend you get a protune for it. These older (seasoned, if you will) generations have too many things to not be left to guesswork of the OTS maps and benefit so well from having a proper calibration done.


-Mikey
 

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2004 Forester XT
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6 Posts
Discussion Starter #4
Thanks for the thoughtful replies skirbykat and mikedrives.

So I asked my mechanic about compression/leak down testing and he wants close to $300 which is 2x the cost of the testers if I just did it myself, so prolly gonna try this on my own first. I have never compression tested a Boxer engine before, any suggestions to make the job easier?

Also, I just changed the oil and didn't keep any of it, how long does the oil need to run before it's ready to be tested?

Thanks again
 

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Registered
2001 Forester STi 6spd with MapDCCD
Joined
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4,642 Posts
Thanks for the thoughtful replies skirbykat and mikedrives.

So I asked my mechanic about compression/leak down testing and he wants close to $300 which is 2x the cost of the testers if I just did it myself, so prolly gonna try this on my own first. I have never compression tested a Boxer engine before, any suggestions to make the job easier?

Also, I just changed the oil and didn't keep any of it, how long does the oil need to run before it's ready to be tested?

Thanks again
Run it to 3k and keep a clean sample ( a few ounces worth) when you change it to send out. Blackstone labs sends a kit with the container (small) in which to put it and send it.
 

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99 Forester 4eat
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46 Posts
You will be better served building it fresh. Blackstone cant tell how much is left in your bearings unless you've established the pattern (it's a history of your engine they build thought multiple test).
OTS tune will be better than stock, but then it will add stress to the bottom end.
 
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