jonb2010

Hi

I am considering buying an Impreza(98-2000) and would like to know how easy it would be to get some extra power out of one. I come from a bike back ground and most cars feel slow in comparison. Last bike was a CBR600 with a 0-60 of 3.5 secs ;-)

I don't know a great deal about Turbos but I know that the boost can be adjusted. How can this be done on the Impreza and is there anything else that needs to be done also ? What sort of money would you be talking ?

Would chipping give a greater increase in BHP per £ ?

Any feedback much appreciated.

Jon

submannz

Most car's will feel slow compared to that even very highly modified. Decent computer and boost controller, injectors, fuel pump and a few other things should bring it down quite a bit.

jonb2010

I'm not expecting to get it to 3.5 secs (I wish though ;-) ). What is the standard 0-60 of a 98-2000 model by the way? I have read a few conflicting figures.

What mod would give the most BHP per £ without going silly money of course ? I was hoping to just be able to adjust the boost to start with like a lot of MR2 turbo owners I have spoken to. How easy is this to do ?

Anybody done it able to give some advice ?

nom

As long as it's a UK, a 'Dawes' manual boost controller will allow to you up the boost until fuel cut (the Dawes costs £50ish I think & is an excellent bit of kit). To raise fuel cut, you need either a 'fuel cut defender' (around £100) or to be OK at electronics & a DIT fuel cut raiser can be made for around a fiver.
Boost on the standard MY99/00 turbo can be raised to around 1.2 bar safely & with a significant performance increase for not a lot of cash!
On top of these two things, you'd also need a boost guage, and being sensible also an AFR meter & something to detect/show knock - the car will look after itself to a point (retard ignitiion), but ultimately you should keep an eye on it too!

jonb2010

Cheers NOM that was what I was after.

Any idea how much improvement in performance or BHP you have achieved with your raising the boost ?

Also what is an AFR meter and what can you use to detect knock ?

SiHethers

Jon

I've got an MY99 impreza. My first mod was a boost gauge and Dawes device. Using deltadash road dyno an increase of boost in 3rd gear from approx 13.5psi to 16psi gave an increase of 30lbft peak torque and 15bhp peak power. These are both at the wheels. I think I probably had samco intercooler hoses fitted too (standard ones are very restrictive) and a K&N filter element.

The main benefit of the Dawes is it brings boost in earlier and holds it higher up the rpm range giving significant improvements in low-down torque and top-end power even if you set the boost as standard with it.

Once you've driven with a Dawes fitted, the car feels slow when you take it off.

Simon

jonb2010

Simon

where can I find more info on a Dawes device ?

SiHethers

Here

Also do a search, you'll get loads of info as there's been plenty of discussion of it over the last 12-18 months

Simon

[Edited by SiHethers - 5/29/2003 4:15:52 PM]

nom

Forgot a bit - but I'm sure you guessed this bit as it's normal anyway - changing the exhaust makes a vast difference, especially the downpipe as there's a plate covering the wastegate on the standard 'item' which considerably reduces performance! A backbox is well worth it too if you like playing around at the top end...