Subaru Forester Owners Forum banner
1 - 8 of 8 Posts

·
Registered
2002 ES300
Joined
·
4,412 Posts
Discussion Starter · #1 · (Edited)
I tried searching, but couldn't find what I needed. ... Anyways, I'm looking to gather info on what rates the stock setup does, versus what it could do maxed out. Or in other words: Get the most out of the stock components I want to get as much power out of my stock setup, being I'm sure Subaru toned things back. So if I could get help filling the blanks, that would be appreciated! And what is the weak link? Which will max out first? Also, how much would the computer be able to compensate for before needing a tune?

Intake
Stock paper flow/max safe flow: _____cfm/ _____cfm
K&N or Green Filter: Stock flow/max safe flow: _____cfm/ _____cfm

TD04
Stock boost/max safe boost: _____psi/_____psi

Injectors
Stock flow/max safe flow: _____psi/cc / _____psi/cc

Fuel pump
Stock flow/max safe flow: _____psi/cc / _____psi/cc

Oil pump
Stock flow/max safe flow: _____psi/ _____psi

Radiator
Stock flow/max safe flow: _____psi/cfm / _____psi/cfm

Waterpump
Stock flow/max safe flow: _____psi/cfm / _____psi/cfm

Also, can I get away with doing a manual boost controller? And how much more gains can I get from a catless up-pipe on a stock setup? A cold air intake and a highflow catback / turbo back exhaust would be the only thing I would look at upgrading.
 

·
Registered
07 FXT
Joined
·
828 Posts
the way to make power with these cars is documented in many different threads, much of the info you are asking for is either irrelevant or does not exist.

If you want to make more power, you need to remove the bottlenecks before worrying about the little stuff. The standard decent upgrade path is downpipe, VF turbo, STI intercooler, and a Walbro pump (or similar) for insurance. And of course a good tune.

After you have all that, a catback exhaust will help a little, a cold air intake will help a little. Auto tranny guys may be able to advise on whether you need anything there, my experience is with a manual tranny.

And do not skimp on the regular maintenance, make sure your plugs, fluids, filters are all good, and before starting any of this you should do a compression test to make sure the motor is healthy to start with, and a leakdown if the compression test numbers are at all iffy.

At the risk of sounding like a broken record, there is no glory in "maxing" the stock turbo, it is a waste of time and will in all likelihood result in a more dangerous (for engine health) setup than a moderate tune with a VF (or similar) turbo.
 

·
Registered
2002 ES300
Joined
·
4,412 Posts
Discussion Starter · #3 ·
I'm not looking to make mega hp with the stock components. Just a jump over stock.
 

·
Registered
07 FXT
Joined
·
828 Posts
I'm not looking to make mega hp with the stock components. Just a jump over stock.
Then follow the tried and true path. For a small jump in power, you do not need to worry about manual boost controllers, cold air intakes, or capacities for water pump, radiator, injectors and all that other stuff.

The weak link is the stock downpipe, change that out and then tune (you WILL need to tune for it). Maybe toss on an STI muffler and you will be stage 2, just like about a million other guys that have done it. No need to reinvent things. After Stage 2, the next step would be to swap the turbo out.
 

·
Registered
2011 turbotek tuned fxt 4eat paddle shift
Joined
·
3,539 Posts
^This there is no reason to over think it. Get a down pipe and a acessport and go stage 2. If that does not suit you go for a larger turbo such as a vf or larger.
 

·
Administrator
2004 Forester XT Premium 4EAT
Joined
·
29,431 Posts
A manual boost controller with no tune? That sounds like a recipe for engine failure. I agree with the others posters... COBB AP should be a no-brainer for what you have in mind. You can wake the XT up mildly on the stock hardware, and it leaves the door open for further upgrades and/or a custom tune.
 

·
Registered
2002 ES300
Joined
·
4,412 Posts
Discussion Starter · #7 ·
Apparently these are more finicky than the late '80s/early '90s turbo's Chrysler put out... Used to something a little more easy to modify without issues.
 

·
Registered
2011 turbotek tuned fxt 4eat paddle shift
Joined
·
3,539 Posts
You picked the wrong car lol everything you do will pretty much need to be tuned for on these subarus. The first thing you should do is change out your uppipe with a catless model. You will not need to tune for it and it wont really make much difference power wise but it will save your motor from a untimely death. The cats get brittle and break into pieces and grenade your turbo and possibly your motor. That is why all the newer model years no longer have them. Also you should remove the banjo bolt screens as they get clogged and starve your turbo of oil also another thing they got rid of. I also just so happen to have a almost new catless oem uppipe you can buy if you cant find a local one. Pm if you are interested.
 
1 - 8 of 8 Posts
Top