Scoobynewboy1

Hi all I have recently acquired a JDM 1998 GC8 impreza, been off the road for 10 years have rebuilt the brakes,... all fresh oil...moted..running fine but i would like some advice about upgrades, i would like more performance but i do not have a endless fund for this car, its my first Subaru i just love it!!! many thanks all advice greatly received

NOSSY_89

Hi mate and welcome, get some pictures up

You need to decide where its lacking first, spool, top end, torque etc. Then go from there. Depending on if its a phase 2 th ecu is mappable, if it is a phase 1 or 1.5 I'm not too sure the best way to go about it is.

adam.pah

Not too expensive to get started. Get yourself a Walbro 255 fuel pump, performance air filter (don't bother with an induction kit) and then a decat/sports cat and get it mapped properly by a competent mapper (Bob Rawle is in Swindon and I believe he maps GC8's). After that you are looking at big ticket items such as front mount intercooler, injectors and turbo upgrades. Remember to improve your brakes in line with any performance mods so factor that in to budget. From experience I'd say you generally get what you pay for so save up and buy decent parts new rather than rushing and using cheap or second hand if possible. And get some pictures up.

NOSSY_89

Mate it is too early in the morning for me but like you said it starts getting expensive on a classic far quicker. Don't forget the 5 speed too.

I need to message you about something actually so expect to see a whats app from me in a bit @adam.pah

Scoobynewboy1

What is the best performance air filter , cobb, jr, ect very confusing for a newbie.
Thank you for the helpful advice

NOSSY_89

If its a phase 2 I've heard of 98's but not confirmed, the mafs are terrible and out of all the different models they are the worst so I went mafless. Any way an oiled air filter can cause a number of issues with these mafs so it is recommended to go with a non oiled filter.

I can't recommend any non oiled panel filters as I am using a cone filter. If you did go oiled I would recommend K&N. If you are going to get a remap look at ECU labs and go speed density. No need to worry about mafs and oiled filters

Gambit

iTrader: (6)

you dont mention if its standard or already had mod's done to it. if it was standard car id be inclined to leave it as such - just upgrade/sympathetically modify stuff like wheel/brakes/suspension/exhaust and leave it std body wise & engine wise - 280bhp is more than enough in them to enjoy it. itll also keep its value better imo

Scoobynewboy1

The car is completely standard, it had been parked on my inlaws drive for 10 years,!!! Thank you for the sound advice

NOSSY_89

I'd focus on the underside then.

adam.pah

Whenever you change things on an Impreza, they need the map tweaked. They're a bit more temperamental than some other cars. With this in mind, I would select a mapper that you want to use and speak to them as each mapper will have their own experiences and, in my experience, can offer you the best solutions for your car.

plenty

iTrader: (13)

How many miles have you done in the car? Is the desire to add performance based on having assessed performance is lacking, or because you want to spend money?

I don't want to sound rude about the latter. We all enjoy spending money on our cars.

Scoobynewboy1

All done underneath, took ages

Scoobynewboy1

I really only want to get the best out of the car.

NOSSY_89

Drive the car, decide where you want to improve it and go from there. Back to what I was saying spool top end etc. If its spool then up pipe and turbo could be a possible route. If its handling then thicker arb etc.

Hope that makes sense mate.

adam.pah

Plenty makes a good point! If you really want to know where to spend your money then take it on a track day and see where you can improve. These cars have a decent power to weight ratio so adding more power often isn't always needed and a few choice handling mods could make all the difference.
Plus you get the chance to actually drive the car at the track without some numpty pulling out on you or heading backwards through a hedge if you do get it a bit wrong.
I believe it's summer action day at Castle Combe in May and you'll be able to book a couple of sessions on track for a reasonable cost.

plenty

iTrader: (13)

Good answer. Make sure the suspension and brakes are tip-top first. Drive it then if you still want more power then look into turbo, injectors, exhaust, FMIC, etc.

Speaking as the owner of a 387 bhp classic, 276 bhp in a light classic shell is more than enough for most situations.

jaygsi

iTrader: (46)

I'd removed the exhaust system and go aftermarket, OEM system is very restricted. Just that alone and a remap will see vast improvement. As said above uprated fuel pump and filter will also help if remapping.

Vxr2010

i agree with Jaygsi , my only concern is , is it a map able ecu ? , if budget runs out then don’t do the exhaust , a re map (if possible ) will make a big improvement , one of the limiting factors is your gearbox , 5 speeds are not as durable as the 6 speed sti ones 👍

jaygsi

iTrader: (46)

That's a good point, might need esl or new board. Think it's £600 for supply and remap for esl.

welder029

I would drop the sump check the oil pick-up pipe could be covered in sludge if it's sat for ten years

lockheed

iTrader: (1)

This, and get a new oil pic up pipe, it costs pennies........ In the grand scheme.
Oil control is everything.
Before investing in all these goodies, do a compression and leak down test, to see if the motor is worth the attention.

Scoobynewboy1

Thank you all for the invaluable advice, I have taken it all on board

Steve Whitehorn

iTrader: (13)

Do the above

I would echo some of what others have said.

First thing I would do is check the body work. sills, Rear arches and turrets. Is it sound. I have seen absoultely mint looking classics writen off because the shell is so far gone under all the spotless bling. It is has problems, that is the first place to spend your money.

Do a compression an leak down test. Pick up pipe, Oil pumps have a tendancy for the screws to work their way lose on them, just be aware.
Goes with out saying stick good quality oil in it and change regulary. The only way you can get a proper accurate oil reading on the dipstick on them. is do it when stone cold on a level surface. Best oil is Silverline, or if not that Royal Purple, Fuchs, Motul

If the car is sound. I would put the money into brakes and suspension. You have rebuilt the bakes so great. I always chuck some decent money at the Pads. Padgid or Performance friction.

Suspension. There is a lot you can do. The most obvious thing that make such a difference is Tyres. For the road on classic subarus as a great all rounder Goodyear Eagle F1s. I have pushed these for hours on alpine backroads in all weathers they work! No good on track mind. Then look at things like ARBs and anti lift kits, drop links ect.

Engine I would leave it alone for the time being. Put a K&N pannel filter in. Change the fuel pump for peace of mind.

If you ever up the power. take it to about 320hp and its associated torque thats the sweet spot...as over that you begin to put too much strain on the OEM gearbox.
340hp you are probably OK I know someone that got away with 370hp on a TY754 box. (obviously its torque that kills boxes not HP)
However 320 hp in a classic with good brakes a good set of tyres and a few suspension mods is a real back road weapon.

Sounds like you are enjoying the car

And here ends my one post of the year

Scoobynewboy1

Thank you for the Advice
Regarding the fuel pump would i need a remap? assuming i go for a Walbro 255, the car is solid apart from a small amount of rust on one rear wheel arch, i do intend to fit a new oil pick up when i change the oil.

Steve Whitehorn

iTrader: (13)

No you wont need to remap when you change the pump. You are just pumping fuel into a system that has not fundamentally changed.
There were fake Walbro 255s floating about years ago. So anything mission critcal stay away from the auction sites and pay a bit more and go to a reputable supplier.

Just be aware that a small amount of rust on the rears can be hiding alot of internal rot. If you need quality proper OEM thickness repair pannels I can put you intouch with someone.

Something else popped into my head. The fuel tank is poorly baffled on them and under hard cornering if the tank is too low you can get fuel starvation. So if on track and pushing it hard dont let it drop below quarter of a tank minimum. On track I am allways topping the fuel up even though I run two pumps and a swirl pot. Nothing to loose sleep over but just something to be aware of.

NOSSY_89

If you have rust on the arches then take out the boot trim and carpet. Be careful not to rip the boot trim because it is very thin, I've ripped far too many lol. Have a look where the jack is and see if it is full of water after it has rained. You can check for rust in and around there and you will be able to see the state of you turrets too.

lockheed

iTrader: (1)

Yes bud ive heard this too, but going back to fuel pumps, you cant go wrong buying one from AS performance, or Lateral performance or scraping the barrel, theres always Roger Clark Motorsport who is expensive and also a complete ****

plenty

iTrader: (13)

390/390 here on a v6 RA DCCD TY754. But OP will have a TY752.

Steve Whitehorn

iTrader: (13)

You have done well!

And OP - as mentioned above
AS performance is a good first port of call for new parts.

jaygsi

iTrader: (46)

Agree loads of fakes out there, I'd go for the RCM one, they had a thread on here some years ago about there quality of goods and issues faced, as made in China. That's what i'd be upgrading too.

Who's this contact you have for quality panels?