Motion-Mx

iTrader: (2)

Hey,



a friend of mine just bought an evo 8 fq300,and it seems to be as quick as my 330bhp ish 03 STi?

so i'm looking for anything I can get to up the horsepower without going to a bigger turbo,car currently has a panel filter,de-cat,de-resonated section,pro drive backbox,prodrive 3-port,silicone intake hose and that's about it,ohh and a race dynamix re map.

Duncan suggested some ported headers,anything else? air intake maybe?

and I take it headers and an inake kit would need a map tweak?

Thanks,Ben

Shmerman

iTrader: (14)

You could look at changing the fuel to a Meth mix and remapping. Other than that its put your car on a diet.

Splitpin

It's not like a 10% difference in power either way is going to be hugely noticable. At end of day you're talking about two quick cars that weigh a similar amount - you'd need one to have quite a significant power advantage over the other before one seems appreciably faster.

As above if you want to make yours significantly quicker then you're going to need a significant power hike, and under normal circumstances the response would be a word beginning with T and rhyming with "fur bow". By ruling that out the turbo change, you're going to be scrabbling around for relatively small improvements.

Duncan should know your car better than anyone so he's definitely the one to ask. Probably not much point fitting a different air intake, won't make you appreciable power at the level you're at.

Induction kit definitely would but as above there's little point. Ported headers, well, in an ideal world you'd have the map looked at but it shouldn't need much doing to it. Again though this is a subtle modification rather than something that'll get you 50bhp on its own.

Of course the other option that is open to you at this point is simply leaving your car as it is. It's not like it suddenly got slower just because your pal bought himself an Evo. If you want to make yours appreciably quicker, a turbo swap is the best way to go about it in terms of return on investment. If you don't want to go to those lengths then, as above, improving the fuelling or reducing the weight both work well. As does looking at your car on its own merits, instead of relative to what your mates drive.

TAM1981

I would have to agree with shmerman a remap for meth would be the cheapest way to add extra BHP but because you have got the stage 1 power upgrade it looks like you will have to spend some £££s for more power.

New headers and flow match uppipe
New better turbo
Bigger injectors
3" full de-cat exhaust
remap

All that above with the stage 1 power you already have could see your sti hitting around the 400BHP mark.

I would save money on the small gains and save up for the big BHP jump.

dunx

iTrader: (3)

I've seen a RR printout of 360 bhp for an STI with headers, etc, but using a std. turbo....

dunx

Jolly Green Monster

iTrader: (4)

fit a td05 18g and map to suit.

see the odd fantastic sti that makes 350~360 on standard turbo on the dyno but it is unusual and not something they will all do.

Simon

dynamix

iTrader: (3)

Very true - would be lovely if they did but as Simon says to gtee getting over 350 it really needs a bigger turbo as everything else is kind of tinkering at the edges. An 18G, SC36 Billet or the creme de la creme MD321H or T if you want to make it a really worthwhile step up in power.

Headers may help but I would say the difference would only be small in your case and maybe wouldnt justify the expense when for possibly less money you can get a bigger/better turbo (if you account for the resale cost of your existing VF35).

Motion-Mx

iTrader: (2)

Hey,

thanks for the input, I'm not ruling out a new turbo...I actually plan on a better turbo but a little short on funds as moving to a new house.

what accompanying mod's would I need to bolt on a TD05? standard airbox etc adequate?


thanks again,Ben

happydude303

iTrader: (1)

i know this battle i have a classic running 390bhp and my mate has a tommy mak evo 6 running 420 and theres nothing in it but we have now come to a gentlemens agreement that there will be no more power i.e bigger turbos just a few little tweaks are aloud now.. but there is always room for improvent but i would say save for a bit get an 18g or even a 20g or if you can save a few more pennys then get the md turbo and let that evo have it lol : > but that is the inner child in me speaking not the sensilbe adult who needs to move to a new house : >

dunx

iTrader: (3)

Doom & Gloom....

Budget for a new clutch, mine gave up at 360 ft.lbs....

Worth it

dunx

jaytc2003

iTrader: (1)

I am waiting for the next post when his mate with the evo has just had a remap (probably get this done very cheap) on the standard turbo and internals etc and be pushing out 380+

happydude303

iTrader: (1)

I am waiting for the next post when his mate with the evo has just had a remap (probably get this done very cheap) on the standard turbo and internals etc and be pushing out 380+ .....

I agree with what you are saying but at 380 even that evo will be on the limits of the standard internals as this is why they used fogred internals on the fq400. the extra money his mate paid for the evo in the first place would blance out... i will say this i, think the evo 8 is my fav evo but id always have a subaru over an evo every day, when i first went to buy a fast jap car i drove and evo and thought wow this is great but just before i went of to the auctions i bump into one of my old mate who happend to have a subaru wrx sti version 4 and he let me drive that and that was the end of that i have me a nice old clasic with good power and a big grin every time i drive it even my mate with his evo has to admit the scooby is more fun to drive but they are both great jap cars

Motion-Mx

iTrader: (2)

hey,

might just hang on and go better turbo then, did anticipate a new clutch would need to go in too.

if all else fails i'll just stove it into the side of him haha

dunx

iTrader: (3)

LOL

Wanna buy a 2.3 Ev* engine that's good for 500 bhp....

Costs peanuts by Subaru standards, my tame mechanic Ben builds them once a fortnight, can't do enough to keep up !

LOL

dunx

a16pse

Ithought all the EVOs had forged pistons noy just the FQ400 .

jaytc2003

iTrader: (1)

The "standard" pistons are rated upto 550bhp by most of the big tuners (evo 8 upwards), its the rods that are the #weak# point but again many with evo 8 upwards are running over 400 bhp with them. (I am currently running 399.5bhp on a standard turbo as well). Depend on the evo all it would need is cams (few hundred £), and an 80 series turbo whih is good for 430ish bhp (along with normal stage one mods)

Happydud I hear what your saying both are great cars, I loved my mildly modded scoob classic, however now I am older I prefer the evo it just #feels# a better car. Dont get me wrong it isnt as raw as a classic scoob, but it does more imo (I am not a scooby hater I love em, before I got my evo I was looking at a v4 type R)

To the original poster, it will get costly to chase numbers with a scoob compared to an evo, so concentrate on things like weight saving, suspension. I would say brakes but again for the evo it is relatively cheap to have a very good fast road setup.

jaytc2003

iTrader: (1)

I agree, costs just over a grand to have a car capable of over that with other supporting mods

Hol

iTrader: (1)

The Classic impreza always had a 10% advantage over the EVO 5/6 as it was lighter. Newage cars weigh about the same, so you need a good 75bhp advantage for it to be 'noticeable' between gear changes

Hol

iTrader: (1)

Thats good advice.

I was looking to buy an EVO 5 in 2001, when I bought a V4 TypeR (it was ready modded for the Ring though ).

Ditch the STI Brembos if you can though - useless!!

harvey

iTrader: (48)

There are quite a few things you can do to improve your car on the existing turbo. Done properly these modifications hold you in good stead should you decide to fit a bigger turbo, which is relatively expensive at a later stage.
Firstly a bit of weight reduction. Junk in the car can be removed, a tow eye front and rear in place of two each end, remove the prop shaft catch plate if you wish and so on. ICE? You may wish to run without spare wheel and jack. What about your own weight?
Fully decat the car. That is good for upwards of 10 bhp and sometimes a lot more.
Ported headers and matched uppipe. Just from the driver seat you will feel the increased torque and willingness.
Keep the hot bits hot and the cold bits cold. Reduce under bonnet temperatures and Keep charge temps at a minimum. For every 4 deg C reduction in charge temperature you will gain approximately 1% power.
Remap.
With these mods in the above order your car will already be noticably faster without great expenditure.

Motion-Mx

iTrader: (2)

interesting read thanks guy's,

I need to get hold of a heat shield to fit around my de-cat,maybe try and save some weight too,the car already has coilovers on however.

I may go with the ported headers,as I'm going to need those for a better turbo anyways,or will I then need tubular?

thanks,Ben

Motion-Mx

iTrader: (2)

what's the prop-shaft catch plate? what's it weigh roughly?

dunx

iTrader: (3)

I'd advise tubular manifolds are only needed to pass 400 bhp comfortably, IMHO.

dunx

P.S. "What about your own weight ? " - a bit harsh Harvey ?

harvey

iTrader: (48)

Not really Dunx as I was thinking of myself!!!
Get the car in the air and have a look and you will see the prop shaft catcher.
Weight? I don't have one here to weigh as the scrap man will have been recently but go round the car and junk everything that serves no purpose. It all adds up.

dynamix

iTrader: (3)

LOTS of weight can come out before affecting how comfortable the car is to be in or drive.

dunx

iTrader: (3)

I'm NOT removing my air-con for anyone....

Sorry !

dunx

dunx

iTrader: (3)

I was thinking of Jeff..... He'll kill me for that one !

LOL

dunx

Rob Day

iTrader: (78)

Im obviously a novice compared to most but the one that stands out to me is the fuel. make more frequent pit stops rather than the 'planned' 60L full tank stops.

A Litre of fuel is around 1.8lb, so if you carry around a full tank @ 108lb.... that wont help

You could half that and make more frequent stops, 108lb is around 8 stone in body weight.

A small help I hope ;-)
Rob


ps, Going back around 15yrs ago, I had a tweak S1 RS Turbo that was a show car, on the way down to Santa Pod I pulled up just outside the outskirts of Santa Pod and filled up (Full tank). I did a 1/4 drag stip in 15.1 & 15.3. We then borrowed some cans and siphoned off most of the fuel and made a pass of 14.3 & 14.4. Granted my reaction time made a small impact as i was getting quicker, but every run afterwards was faster than the initial 2 runs (which relatively obvious and stands to reason)

Oh and dont take the **** with the times.... It was only a 1.6l lol

Motion-Mx

iTrader: (2)

come on Duncan,

let's see a list!

dunx

iTrader: (3)

Std Front seats weigh 20+kg each....