I'm in the market for an impreza sti, the forged ones seem to be few and far between that I like (hurst had a silver one but Its sold), so i'm thinking about buying a none forged low ish sub 60k mile one. Whats the rough cost of a forged lump, and once its done is that it ? Does it require any extra maintenance or are there any hidden costs. I would even buy one that needed an engine but again there are none for sale.

 

Don't go for a cheapo rebuild with someone who doesn't know what they're doing. Ask around if you don't know who is good and who isn't!

David at API posted an estimate for one of his high quality builds on the 2008 hatch thread at the top of the forum. You're looking at around £3k to have it done with a custom remap.

A standard 2.5 is recommended to be serviced every 10,000 miles which I think is too long especially given the rate these things can be known to drink oil. A forged 2.5 is a glorious road engine, you would most likely need to change the oil every six months and stick to a cosseting service schedule with an experienced specialist - assuming you stick to a power output under 400bhp.

 

As above really.
What about buying a good low mileage 2.5 and running that? And IF it fails then forge it? The standard sti 2.5 is ok for 330ish so will be a quick car still.
My 2.5 managed 75.000 before it let go
I'm getting it forged ASAP and can't wait to get it back on the rd
I hope you find what you want

 

There's no reason why a forged engine should be any worse in any area, and they are more likely to stay in one piece. One of the issues concerns the OE head gaskets, which suffer from blow by and can certainly contribute to piston ring land failure. I'd say with careful engine building to include Cosworth or RCM head gaskets and ARP studs you shouldn't be looking at problems.
A £3k build is possible, but I'd be adding more to it on the basis of fix it once, fix it right.

 

Theres a big difference between an estimated cost and actual, i went over by 1k but rather that than rebuild again later realistically 3.5k to 4k for a real good strong build

 

I picked up a forged hawk just before christmas on the advice of a few people. The receipt for the rebuild is just under £4k. Paid more of a premium for it over some of the non forged ones but im happy with the peace of mind that comes with it.

 

It is important to remember that there is a big difference price wise between a forged engine, which is attainable for the sums being referred to and a forged engine with all the supporting ancillaries (e.g. turbo, fueling, exhaust, etc) that will allow you to exploit the potential of the forged engine. If you want the latter you're looking at a bill in the 5 figure range.