FSTI Exhaust

Author
Discussion

Shinobi

Original Poster:

5,072 posts

190 months

Wednesday 8th February 2017
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Looking to purchase imminently and I have been looking at the Hayward and Scott, Afterburner Vortex or a custom one made locally. Cost seems roughly the same for each option.

What I'm looking for is some burble, noisier when I hit the fun peddle but something I can live with, I've done the V8 with straight pipes and 3" Blitz Nur on an Evo so I have lived with loud before but I'd rather not.

The back box that Mr Trent had fitted sounds perfect and it can be purchased with the centre section fairly reasonably, my query I guess is what would be the advantage if any for purchasing a 3" over the 2.5? I'm looking to run max of 350bhp with supporting mods of filter and remap. Certainly not chasing the power but I noticed a few people mentioned running around 340 with a 2.5".

Any thoughts widely appreciated

vxr2010

2,565 posts

159 months

Thursday 9th February 2017
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has engine been forged and do you have a sports cat ? personally if not forged i would not aim that high on standard internals , but that's up to you , is it also the standard turbo as you get into the area where you start running out of boost on mine the max was around 1.25 to 1.3 , somewhere between 310 and 330 works well and fine on standard size exhaust , i heard litchfield had a lot of fsti failures when they had been mapped with standard internals , other fsti owners may come along with there thoughts but i've had two now and both have failed on standard internals and both were re mapped so have i been unlucky , i know i'm much poorer lol but still prefer the fsti against any other car i've driven

Shinobi

Original Poster:

5,072 posts

190 months

Thursday 9th February 2017
quotequote all
Thanks, I'd be more than happy with 330, realistically it's a bit of noise I'm after but not too much and any power gains is a treat.

The Hayward and Scott set up seems to list 18hp increase which sounds great to me but I've read about detting in the engine so I would look to get a map and make sure everything is safe.

yellowstreak

615 posts

152 months

Thursday 9th February 2017
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I have a full 2.5" H&S on my FSTI. Its not mega loud, but certainly louder than standard.

TartanPaint

2,988 posts

139 months

Thursday 9th February 2017
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I wouldn't do 2.5" unless you are trying to keep things quiet AND cheap. As you say you do want more noise, definitely fit 3", and control noise by how many cats and resonators you delete.

I made the mistake of sticking with 2.5" because I wanted a quiet car, but exhaust back pressure quickly became the bhp bottleneck on the rolling-road, and boost had to be dialled back a bit. I wish I'd dug deep down the back of the sofa for more pennies, and fitted a 3" system with all the quiet bits (sports cat, resonators etc). I'd have another 20-30bhp and probably not much more noise.

Shinobi

Original Poster:

5,072 posts

190 months

Thursday 9th February 2017
quotequote all
Thanks the cost difference is very small so not concerned with that, I've read about people losing Torque from having the 3", anyone experience this?

Pretty much decided on Hayward and Scott, now it's just between the 2.5 and 3"

vxr2010

2,565 posts

159 months

Thursday 9th February 2017
quotequote all
at 330 i would go with the 2.5 , the 05 fsti i have has a bigger bore plus sports cat but does not feel as quick as the 04 fsti , it feels like it has less grunt , it is maybe down to the map i don't know , but i prefer driving the 04 , the differences between them is not massive both produce around 1.25 bar , i personally with that power would stick to 2.5 but again it's your choice , i would expect a 2.5 to be fine with 330 , on a na car too little restriction takes power away from them , on turbos maybe the same ? it can be noisy but still restricted enough , on the impreza the centre delete helped but it was a standard cat and a slightly sporty back box so maybe not too much restriction taken out , if power was over 330 i would probably go bigger as extra grunt would offset apparent loss of grunt in a bigger bore , what did litchfiekd do ? same size bore on there fsti at 330 bhp ? that's my thoughts your decision

vxr2010

2,565 posts

159 months

Thursday 9th February 2017
quotequote all
best thing for me would be a drag race for my cars i've always wondered which is the quickest , after 80 mph the turbos seem to get left behind by the v8 , but i think initially there would be a few changes regards the quickest one

Shinobi

Original Poster:

5,072 posts

190 months

Thursday 9th February 2017
quotequote all
2.5 inch cat back ordered from H&S along with a Cosworth air filter :-) good times!

Edited by Shinobi on Friday 10th February 12:18

vxr2010

2,565 posts

159 months

Friday 10th February 2017
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a good choice

TartanPaint

2,988 posts

139 months

Friday 10th February 2017
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Yup, good choice. That'll sound lovely.

vxr2010

2,565 posts

159 months

Saturday 11th February 2017
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i asked a tuner about the exhaust , 340 to 350 bhp it helps slightly from there up to 400 but not a lot in it , 400 plus needs a bigger bore , personally on an fsti 310 to 330 bhp is a good ball park area to be , yes you can go higher but personally i feel from the mpg wear and tear angle i feel that is enough , a fellow owner of an fsti went the whole hog turbo injectors etc engine broke in the end and not long after the mods , and in his own admission he said he wished he had just mapped and sports exhaust and left it there , i'm sure a car with more bhp is quicker but by much ? and at what cost ? i know mpg gets killed with more power but for me it's a daily drive too so want to keep mpg sensible .. ish

Shinobi

Original Poster:

5,072 posts

190 months

Saturday 11th February 2017
quotequote all
I had a chat to Bob Rawle and he agreed 2.5 is the best bet for what I want to run, can't see me wanting more power as I don't use what I have but a little bit more noise would be great.

mmcd87

626 posts

203 months

Saturday 11th February 2017
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Shinobi said:
2.5 inch cat back ordered from H&S along with a Cosworth air filter :-) good times!

Edited by Shinobi on Friday 10th February 12:18
Hi, have you gone for a straight through centre section of resonated?

Shinobi

Original Poster:

5,072 posts

190 months

Sunday 12th February 2017
quotequote all
mmcd87 said:
Shinobi said:
2.5 inch cat back ordered from H&S along with a Cosworth air filter :-) good times!

Edited by Shinobi on Friday 10th February 12:18
Hi, have you gone for a straight through centre section of resonated?
I went for this one https://www.haywardandscott.com/subaru/forester/fo... doesn't state that it's resonated so I don't think so.

Shinobi

Original Poster:

5,072 posts

190 months

Saturday 18th February 2017
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Looking forward to this!

vxr2010

2,565 posts

159 months

Saturday 18th February 2017
quotequote all
it will be a lot better with that set up , you will notice much better flow and a bit more noise , you will realise what you have been missing all along , and it has the centre section delete even better

Shinobi

Original Poster:

5,072 posts

190 months

Saturday 18th February 2017
quotequote all
It sounds a lot better! Not boomy, lovely burble on tick over and around 4K revs is wonderful. Very happy with this. Thanks again guys for all the info. Also seems to pull better from low revs but that must be in my head I guess.

Shinobi

Original Poster:

5,072 posts

190 months

Saturday 18th February 2017
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The wife asked "will it be quieter now you have gotten rid of those noise boxes" bless

vxr2010

2,565 posts

159 months

Saturday 18th February 2017
quotequote all
it will flow better and a few more bhp , and of course it's quieter ...maybe