Sorry don't want to hijack the thread but thought I might provide some comparison for those looking at big builds or engine conversions.
I have recently did the rough numbers on what I have spent on my build.
It has taken time to source parts and I have fabricated some parts to bring costs down, sold some bits to pay for other etc etc.
my base car cost me £6500 around 18-24months ago
you could do things cheaper but with patience and some hard work you CAN get 400bhp for much less than £3k.
I went for a bored and stroked bottom end that will support significantly more, but I don't like doing things twice. I am also doing this with a spare block so I have a full stock engine to sell on if I wanted to to cover some of the cost.
You could substitute the turbo I chose for any GT30 on a 1.8 with stock pistons, forged rods, use a cast mani, £100 eBay 3" downpipe and slash cost off my numbers below.
The costs below are actual costs I have paid, not just estimates on a wish list.
For reference a GT2871 .56 trim on an off the shelf APR stage 3 tune fitted to a 1.8t BAM engine in a TT produced 310bhp (at the wheels) at 20+psi. They (APR) estimate this to be around 380bhp at the flywheel.
I will be disappointed if I don't have between 325-350bhp atw with my build. that is over 400bhp (fw) by most estimates.
any number of these on lesser builds running low 300's atw
http://forums.vwvortex.com/zerothread?id=3502059&postid=42689825#42689825
costs:
Engine
Block £0.00 (courtesy of Macca! cheers)
83mm bore/hone £75.00
Scat Rods 144mm US$349.00 £171.00
Supertech Pistons 83mm 9:1 $599.00 £295.00
Main Bearings US$67.00 £33.00
83mm head gasket US$85.00 £41.80
Raceware Headstuds US $269.00 £132.50
Raceware Main Studs $165.00 £81.28
Supertech In.&Ex. Valves $469.00 £231.03
SuperTech Titanium spring/retainers $469.00 £231.03
92.8mm forged Crankshaft US$300.00 £147.78 (polished and magnafluxed)
630cc Injectors CA$300 £150.00
spare DBW ECU CA$200 £100.00
Tapp Auto Map CA$700 £350.00 (may have it custom done depending on result)
90mm MAF/Harness CA$200 £100.00
GT2871 .56 trim £550.00
Exhaust/Inlet
Manifold bends and tubing £450.00
Forge FMIC £0.00
D/V forge £0.00
DXD stage 4 clutch US$585+60 £315.00
2.75" miltek £100 (eBay bargain!)
Subtotal £3,454.42
Suspension
KWV3's £950.00
full polybushed + suspension work
inc fitting v3's £1,300.00 (that hurt!) all new front lowers, complete reset of geometry to custom numbers
Rs6 18"s (5 with tyres) £410.00 (love eBay)
Brakes
new 4 pot Porsche calipers+pads £200.00 (love german eBay more!)
rs4 front\+rear discs and rear calipers £200.00
adapters/bolts £60.00
s/s hoses £80.00
Body
S4 front bumper £150.00
" rear £40.00
"sides £120.00
misc parts £78.00
I have/had enough on my plate without a complete engine/loom/fuel/exhaust/inlet conversion to contemplate.
good luck with whatever you decide