Which is the best engine???
 

Hello peeps,

a friend and I are looking at building a factory five 818r which is a mid engines car which uses the impreza as a donor car.


The choices are any impreza bar the sti from 2002 to 2006. I think there are 2.0 and 2.5 engines to choose from. It would be nice to be able to run about 350 to 400bhp ideally using standard parts as in intercooler, rad etc.

I know nothing about scooby's so if anyone can offer some advice that would be most apreciated.

Many thanks

Raj

That sounds a bit strange, why can't you use that engine but you can use a later 2.5L.:wonder: As the 2.0L of that era are the strongest and will handle your target power, (good for 450bhp)

All the engines are physically the same size and the one you really want is from a 2002 STI but any of the 2.0L UK STI engines will be fine at that level, you'll also need a 6 speed gearbox from an STI too if your going north of 350bhp.

Hi Raj

Personally I wouldn't choose 2.5L STI engine,they're weak engine and if you want push safely 350-400bhp then without the forging the internals this can be very difficult

Due this personally I would go route of the 2.0L STI(preferably JDM) and with those engines you shouldn't have any issue to run this power for long period of time thre

Hope this helps

Thanks,Jura

thanks very much guys for the responses, you have said what I wanted to ehar as these cars are a lot cheaper to buy than the 2.5 versions. I know these kits go like strink with just 260 bhp so im thinking 350 may be too much but its always nice to know if you want to up the power you can do without too much messing about.

As for not being able to use the sti engine im dont know why this is, perhaps something to do with extra electronics? complex diff controls etc I dont know, but there is an option on the build to use the 6 speed box from them.

If you get a min have a look at the 818 r here, im in love with it tbf

http://www.factoryfive.com/kits/project-818/

Looks good Raj, power to weight ratio would be an advantage by the looks of things.

Get a thread up in the projects section when you have all the gear as there would be a lot of interested people on here :thumb:

Will do, that would be great as im sure I would need a lot of help from the people on this site.

The plan is to keep using my track car while I finish building my Fiesta mk1 which shouldnt take too long now, once thats done sell the track car to make some room for the new build. Just bought a new house and need to extend the garage whilst her in doors is let loose with the house refurb. She is a weapon lol.

Hopefully either end of this year or early next year we will be taking the plung and ordering a couple of kits, they arnt cheap though, around $13000

And the 818 stands for the weight of the car once built, so power to weight is a lovely ratio to look at,,,,,,,, not to mention drive I would imagine.

FYI here is a few pics of my little track car "Dom"

Attachment 48264
Attachment 48265
Attachment 48266

Very nice, is that bike engined?

From Factory Five themselves "STI’s drivetrain parts differ too much from a standard Imprezza or WRX for use as a single donor for the 818 platform."

Well that makes sense, im glad they have made a kit to utilise the 6 speed box, plus it would be interesting to see what sequention options are around for this engine.

Yes Dom is powered by a K4 GSXR 1000 engine, nothing crazy but the car is very high spec, best thing about it is the flatshifting, you have 2 buttons on the steering wheel for gear changes, you feel like a racing driver when you on track...............and the dam thing isnt broke down lol

Awesome :thumb:

Good luck with the purchase, I'll be watching this space!

On the other hand if you want to save yourself about £3k you could aim for slightly lower bhp around the 300/320 mark and use a 2002/2005 WRX engine and running gear and a little mechanical sympathy.

Hi there

Personally I would go with 2.0L STI engine as first starting point,you can buy 2001 STI now for £6500 easily and with this you will have nice starting point,if you will choose later STI which does have DCCD,later DCCD does use complicated system which can be hard to replicate,but you can buy from DCCD PRO which will replicate DCCD as should,this cost bit more,but I would say will worth it

There is no big difference between the newer STI(2.5L) and earlier 2.0L STI,main difference will be in engine and with some electronics like ECU etc,but nothing major which will make any big difference in build like and same I can say with WRX,WRX is weaker model in many ways like weaker engine,gearbox etc but still if you are not looking break 350bhp then is good starting point,but I would rather choose 2.0L STI as starting point there

You should be able to use STI engine in yours and gearbox not sure,but I would say is possible there

USDM STI are differ from our earlier STI what I know,our earlier STI are 5x100 and non DCCD and USDM STI are usually 5X114.3 and DCCD,if DCCD making not possible to use STI engine on yours,then I wouldn't be worried about this there,as above DCCD Pro should sort this

Just please ask them why you can use STI on yours

Hope this helps

Thanks,Jura

Having looked at their website, they suggest a whole car WRX as a donor.....

This is because they use the five speed gearbox.

This would not stop you using the stronger STI engine with it's associated gubbins ( ecu, loom, clutch, TMIC and turbo ).

SO, you could buy a WRX with a blown engine, and then source an STI engine and bits from a breaker.

All IMHO.

dunx

P.S. A 300bhp 2.5 WRX isn't too likely to struggle with only 800 kg to shift....

i think the sti requires a lof of custom parts to the chassis so they say to use a normal WRX. I have seen tatty ones go for around £2000 (2002) which is mroe like my budget, would a 2002 engine be able to cope with around 300 - 350bhp on standard internals? there is room for mods to the intercooler to reduce charge temps further etc

from andy forest website:

Level 2 290-310 bhp

Full Decat or Sportscat exhaust from turbo back 2.5 or 3” bore.
Decat uppipe Pre turbo
Walbro 255 l/hr uprated fuel pump
K+N panel filter
Ecutek Custom ECU recalibration
Twin boost set up for high/low power switchable in-car
AFP 04-H custom ported hybrid turbo
High Flow multi spray fuel injectors 550cc (380cc as std)
Uprated turbo to intercooler 'Y' pipe
NGK PFR 7B uprated spark plugs

Hi Raj

STI engine have same dimensions like WRX engine,there is difference only in internals used and AVCS,but if you will be using STI ECU then you should be OK without the questions and other parts fits WRX from STI too like gearbox etc,many people running over here gearbox from STI on their WRX

But yes standard WRX if has been maintained then should handle 300-350bhp,but I would say 350bhp you will be pushing the luck,but should handle,how long engine will last that's the question

As I said,if you want have safe or safer 350bhp then STI is better choice as STI will come with VF35 which should make 330-350bhp on yours and on WRX you will need bit more parts to get close to 350bhp like larger injectors(550cc injectors),better TMIC( preferably STI TMIC or FMIC) and better headers(STI or ported headers I would choose and better Up pipe if moneys allows) plus decated exhaust and few other bits and bobs

Hope this helps and good luck there

Thanks,Jura

With such a low budget for the donor car and what I know now, I'd buy a well maintained 02/04 WRX, de-cat up pipe, port the turbo myself and go the PPP route with the ECU which is a simple re-flash and see how I get on, I'd also fit an Air fuel ratio gauge and keep an eye on it to make sure it wasn't leaning out under load, in theory it should be fine as the PPP map is known to be rich, but better to keep an eye on it.

Then at a later date if you feel the need for some more power have a custom Ecutec map done which should put you pretty near 300bhp. PPP is 265bhp but with a decat up pipe and ported turbo you may see slightly more.

I'll be doing this in the summer and will let you know what my AFR's are like.

thank you for the reply Jura,

thats some really good info there, I think I will probably just get the cheaper wrx to get the car built and then perhaps look into an engine swop further down the line, 260bhp will be more than enough to get to know the car i think lol

Cheers Ditch, the fueling/mapping side of it will be taken care of by a good mate of mine who runs Unicorn Motorsport Developments, he should be able to remap the standard ecu direct instead of a reflash but will need him to have a look at it first.

Hi there

Again I would have look on the 818 forum where guys should help you,but what I'm reading there,people don't want to use STi due the DWB(Drive By Wire) which on UK models have only 05 onwards cars,not earlier STI

Here is thread

http://thefactoryfiveforum.com/showt...670-WRX-vs-STI

http://thefactoryfiveforum.com/showt...r-Build-Thread

Hope this helps

Thanks,Jura

hmm so an sti may still be viable then as a donor

Except for the larger/heavier gearbox...

dunx

The 1.9 AWX Tdi VW engine = bulletproof!