Jimmybeattie

Hi guys, I've just bought my first Scooby, a forester turbo import and I have to say I'm very impressed. The 4wd system has been excellent these last few days getting me through very deep snow and thick ice. Once this weather has cleared though I'm going to be after a wee bit more power. At the moment the car has a full stainless exhaust (powerflow), an induction air filter but I forget which make, an aftermarket dump valve, and a manual boost controller. It also has impreza sti suspension and unrated brakes so it should handle a power increase ok. At the moment it runs a pretty constant 9psi boost but I was wondering if it was simply a case of turn the boost controller up a wee bit to maybe 11psi for an increase or is this asking for trouble? Don't want to screw up reliability.
Also the car is an auto and has been converted to LPG if that makes any difference
Thanks in advance for all answers

NINJA ED

iTrader: (2)

Get it to your local tuninjg centre and get it on rolling road m8 see how its running soon tell you if its safe to turn up or no. Be able to see how your fueling etc is

TonyBurns

iTrader: (3)

What year car is it? and what is the exact model, ie Forrester STI for instance.

Tony

ClintUK

Hi Jimmy

Welcome to your new hobbie, 'a bit more power' is a slippery slope but many of us find it very rewarding.

I can't be of too much help as I have no idea about after market dump valves - I think I'd call it a wastegate valve and most turbos on Subarus have them built in, so not sure where you are at.

Modifying to LPG does make a big difference as the ECU will have been remapped and this will need to be done again. Good luck with your investigation, I wondered a few years ago about healthy power using LPG but didn't go down that road, but might yet.

As for you going forward, even with LPG there are basic requirements for more power, better breathing and more fuel into the engine - pretty simple really.

Standard Scooby inlet systems are pretty good upto 300 - 350bhp.
Exhaust however can usually be improved quite easily but the cat back systems dont give much improvement to start with. You need to make sure you have a down pipe that matchs the turbo exhaust exit, standard ones (on older Subaru) are very restrictive. This pipe hold the cat too and you should get a sports cat. They are 200 cells or less on the cat honeycomb, with more catalyst on the substrate, standard ones are 400 - 600 cells per sq inch (I think) so you can see they are much more restrictive.
As far as fuel into the engine though, I have no idea about the limitations of LPG delivery systems.

So first thing first - figure out what the 'after market dump valve is doing' they are not generally considered an 'up grade' depending on its implementation.

Then get a Sports cat and a remap.

Best of luck

jura11

iTrader: (7)

Hi Jim at first congrats to buying Forester.Probably best thing if you rid off the Manual boost controller(these ECU have very good boost ability for controlling the boost with proper remap),and about the remap(everything will depend which turbo you are currently running,if you are now running,but realistically around from 270-280BHP(TD04)-330-340BHP(VF34-35)),remap cost around 300-350£(Open source remap)or 500-650£(EcuTek)...
Now at the auto(i have same 4EAT and mine running with some upgrades around 330-340HP),this 4EAT use Impreza(which i have),its no problem if you are running the LPG(i'm running too and you must go to your LPG installer(fitter) adjust the map for bigger BHP, because LPG ECU is separate from normal ECU)

MarkCSC

Firstly congrats! Fine car Foresters

Secondly, tell us what it is and we'll be able to give more help. For example if your car is a 1997 (like mine) you can't remap it and boost controller is the only option unless your go for a new ECU.

9psi sounds like standard boost pressure so you should be able to increase it a bit. Article here from a guy who fitted a boost controller to his S/tb auto http://www.mykp.co.uk/my-cars/subaru...oller-Install/
Depending on what boost controller you have, if you go too high you'll get fuel cut (feels like you have driven in to a brick wall). This is about 14 psi.


For more Forester related stuff make sure you check out http://www.subaruforester.org/vbulletin/f75/

Mark

Jimmybeattie

the car is a 97 r plate s/tb, hope this helps