Boost control and exhaust silencers

[Roars]

Hey all

 

so a couple of questions I would like some advice on if you would all be so kind about my classic Impreza.

 

1. Exhaust.

When I purchased the car all it had in the ways of performance mods was a remap to 258bhp and your typical 3" exhaust system with a 4" through silencer which had pretty much no sound deadening at all the o.d. of the silencer box was 5" so it was never going to be quiet, it was good to begin with, sounded nice but it was extremely loud, after I stripped out the interior and left nothing but the two front seats and the dashboard behind it was a wee bit too much sat inside, and then my neighbours started to complain about me leaving for work at 6:45am and coming home past midnight. So with there bitching and my ears bleeding everyday I decided to try and quiet it down a bit, I just brought a standard rear box and cobbled it on. It was great being able to drive in comfort again and come home at what ever time I wanted with no hassle but my partners standard 1.1 3 cylinder Mitsubishi colt makes more noise than my Subaru now and I would love that rumble back, and i have lost a few ponies along the way too. My plan was to keep the back box for the sound deadening to keep noise levels down but cut the baffle, exhaust tip and inlet pipe off/out and replace it all with a 3" baffle , tip and inlet. Do you reckon this would still sound Quiet enough to keep my neighbours at bay, give me that infamous rumble again and give me a pony or two back? At a guess I think it's a 1.75" system in the back box.

 

2. Boot control solenoids.

i had a few bits kicking round from a previous build I had going (ca18det powered mx5) and like all unknowledgeable people I though to myself to chuck my gizmo electronic boost control solenoid on it thinking more boost would be a good idea, I have come to realise after a bit of carful reading of the internet that i in actual fact am putting my engine in danger so how much can the stock solenoid actually handle if I were to get it plugged into a computer and put on the rollers? I was looking at better solenoids available to work with the ECU but is it worth spending £125 on one if the stock one will achieve what I want? The gizmo controller I added made a massive difference on power but I don't want to have to rebuild my engine if I can avoid it.

 

3. Turbos

so I have a garret t28 sat in my house doing nothing, I know I would have to have a flange adapter to fit it to the manifold and cut the down pipe flange off and spin it 90 degree but a bit of mechanical work wouldn't faze me, I have been fixing things since I was nee high to a grass hopper, spent a few years of my younger life as a HGV fitter so I can spin nuts and bolts and weld stuff up no problem. Just after a few more bhp and if I can do it for next to nothing myself then bonus

 

thanks in advance 

[Tidgy]

1. you may want to look at a full race spec decat, there fairly quiet when just tootling around, have a nice bark when you give it right foot, yet not restrictive on performance.

2. you don't need any external boost control, that's what the ECU is for ;) If you want to up the boost then remap it or your asking for an engine build bill.

3. second hand turbo's arn't big money and are typicly bolt on and work, if the turbo's not right for the engine it wont work and be laggy (although could work very well, untill you fit it and have it mapped you wont know either way). New turbo means full remap or your asking for trouble and engine build bill.