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-   -   a good way to spend 5k (http://www.subaru-impreza.org/forum/subaru-impreza-discussions/58335-good-way-spend-5k.html)

smoothop 28 Jan 2009 07:20 PM

a good way to spend 5k
 
Hi i have a 95 STI, it currently has the turbo boosting at 14 psi. it was like that when i bought it. im a complete novice to scoobys. im used to skylines. so in a way this is a step down for me. as this is my first scooby. i want to treat it right.

im prepared to go up to 5k, as i know from skylines when you spending that kinda cash you go straight for a turbo. but im not sure the koo with scoobies so any advice and parts ideas would be very welcomed and even and estimate of cost all the way up to 5k would be awsome. it does have aftermarket suspention on it. they are adjustable from the top but not coilovers. it also has a litchfied exhaust system with decat

so what im askin is. if you had 5k to spend on this scooby what would you do ?

stiimpreza1984 28 Jan 2009 11:46 PM

Re: a good way to spend 5k
 
This is a thread by Tidgy


Tuning realy depends on your budget, no mater what model car you have.

i've gone from a more or less standard car (my00 classic uk turbo) to one thats got very few parts left in origional condition, but to do that i've had to throw a shed load of money at it.

shall base the upgrade stages on a classic uk turbo for now.

so first things first, decide what you want from it, do you want to do easy mods that will help the performance, or do you want to eventually go the whole hog?

The basic engine mods start at decatting, uprating the air filter and remapping. on a classic at this stage a uprated pannel filter is by far the best option insetad of an induction kit.

Generic chips arn't worth it (excluding the PPP kit) the maps are either too general to make large differences, or they can cause serious running issues risking the engine reliability.

the basic cost is roughly 1000-1500 ish to get to this stage, and should boost performance from 215bhp 215ftlb to 260bhp 260ftlb (as a rough guide, exact figures vary from car to car).

Next are basic suspension changes.

uprating the rear anti roll bar will remove some of the generic understear presnt in impreza's. (roughly 150)
Drop links will stiffen up the connections between roll bar and the car (roughly 100 per end of the car)
anti lift keeps stops the front end from going up and down as much, however this means a geometry setup is required. (combined roughly 200-300)
Strut braces will reduce body roll (120 front upper, 120 front lower and 100 rear)
basic upgraded springs (stiffer) (250)

then basic brake changes

Also brakes should be uprated, 4 pots should be a minimum (although post 98 cars will have them as standard)
uprate fast road pads (140)
uprated brake lines (50-80) further improve braking responce
uprated groved disks (140-250)

for all of the above your probibly loking at 2000-3000

After that it start to become more involved and much more expensive, but also depends on model.

Bake upgrades mentioned above are a must, and possibly the introduction of a uprated 6pot brake kit (1200 -2000)

Full uprated suspension, including dampers and springs (800 for a full kit), adjstable is possibly the best option at this point, they tend to allow even stiffer settings but also allow for softer to be used when required.


Power wise your lookng at changeing the turbocharger, fuel pump and a remap to suite, however you'll hit a limit at around 320bhp on this set up.

roughly an addition 3000 (total 5000-6000)

to get to where i am now (340bhp)

you'll need, uprated turbo (250 for a second hand one up to 750 for a brand new vf34), front mount intercooler (450), induction kit (100), uprated oil cooler is advisable (450), a full set of gauges (650 for defi's), some cars also need new large fuel injectors (400),

also your at the very top limit of the gearbox, an uprated on is either a straight cut ppg or similar kit (3000) or a switch to a 6 speed gearbox (2000). the standard clutch wont cope and will need uprating (450).

The standard ecu may become a problem at this level (1500)

now as a rough guess your up around the 11,000-13,000


Once your past this point then your alkind serious money

the engine isn't up to the job, rods block and pistons can't take te boost pressures and will need replacing. Head bolts wont be strong enough, headers will be restrictive, as well as all the parts monetioned above becomeing also not up to the task.

a full custom rebuild to get to that sort of power your talking (very very rough guide), with varous of the above mentioned parts

7000+ for 400bhp
12000+ for 450bhp
15000+ for 500bhp

and the cost per bhp goes up and up, past this point its so variable as to the cost you can't give guess figures, they have to be priced up professional.


The price shown are rough guides and vary dramaticly depending on tuning company and market prices for parts.

however what i can tell you is there are some off the shelf engine that can gve mega performance and for what they are arn't overly pricey (in context anway lol)

Scoobyclinic do an off the shelf SC450 package which iirc is 12,000 plus vat for a 450bhp engine, icluding suitable clutch and gearbox. hich is very good value indeed, but is a whole different ball game as far as performance goes.

So it goes back to the question, how far do you want to go, and whats your budget.

hope that rough guide helps.
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rikimaru 29 Jan 2009 02:45 AM

Re: a good way to spend 5k
 
What state of tune is the car in now? That will influence a great deal where you start and how much you'll need to spend to support that new turbo. Also what kind of power gains you looking at? Is it still on the standard ECU?

If you're standard power wise then I personally would go for the uprated panel filter, uprate the ECU (this is optional but it is what i would do for many reasons if it hasn't been done already as it allows for far greater power gains down the road as well as other useful stuff like running MAF less etc.), uprate fuel/oil pump, uprate the injectors, uprate the turbo (VF34 or 35) and get a re-map.

If you've still got cash kicking about then go for a front mount intercooler, and forget the panel filter as airbox will have to go for an induction kit anyway.

Also don't forget that you may want to think about uprating your brakes at this point too. Standard caliper set up (at least if you have the 4 pot front/2 pot rear config) are OK on a standard motor but wouldn't want to keep them much beyond 300 Bhp personally speaking.

smoothop 29 Jan 2009 12:33 PM

Re: a good way to spend 5k
 
the car as im aware has uprated suspention you can adjust it from the top but i dont think they are coil overs. the air induction is a k&N pannel filter. the exhaust is a litchfied system with decat and the psi of the turbo is 14 psi from what i have been told. but im really starting to like this scooby. just the feel of it brings a nice smile to my face. the roor of the enging not even a skyline has that. lol but i feel it has it in it to go quicker. i notice it has quitea bit or torque steer. im not sure if that is the right term but when you accellerate at an apex it tends to go straight lol

smoothop 29 Jan 2009 12:39 PM

Re: a good way to spend 5k
 
btw thank you stiimpreza1984 that was a fantastic quick start guid to how things are done with scoobys. i really appricated the time you put into that reply

it helped alot

thanks again

rikimaru 29 Jan 2009 01:45 PM

Re: a good way to spend 5k
 
Quote:

Originally Posted by smoothop (Post 303182)
i notice it has quitea bit or torque steer. im not sure if that is the right term but when you accellerate at an apex it tends to go straight lol

That'll be the dreaded understeer that Scoobys are famous for.;) I've got a manually adjustable center diff (DCCD) so can shift a lot of the torque to the back which eliminates a lot of that.

I think torque steer is when you accelerate the power causes the car to pull to the left or to the right.


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