Seems initially excessive but I can't see another option?
Rough prices were I to stay F4R:
-Rebuild, £1500 (massive kick in the balls cost too just to get back on track)
-ITBs, £1500
-Headwork, allow up to £800
-Bigger cams, £800
-Mapping, £500
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£5000 +/- £500.
Result = up to 240bhp depending on cam choice really, and forged bottom end not suited to daily winter abuse again, meaning what another rebuild to 83.5mm next year!?
Vs.
-K20 engine, £1500
-Box, £500
-Loom, £100
-Cams, £1100
-Double springs, £300
-RBC inlet, £250
-Mapping, £500
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£4250 ish
Result = 250-260bhp, stock bottom end able to take everything you can throw at it.
Now I appreciate I haven't factored install yet, but going Honda and I'm already £1000 up.
Plus I can sell the good bits from my engine (rough off the top of my head prices for now):
-Arrow rods, £500 (awesome rods about £1100 new)
-Pistons, £250 (£576 new and nothing wrong with the pistons - you'd buy new rings anyway)
-Head as-is, £700 (includes £700 cat cams, £144 cat cams springs, £384 Supertech valves)
-Misc stuff, £250 (TB, inlet, all sensors, injectors, coils etc)
-Gearbox, £800 (rebuilt 6 months ago with maybe 4k on it, new 3rd and 4th syncro, 003 ratio set with 4.7 short final drive, Quaife)
-TTV Steel flywheel, £200 (£327 new)
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I think I can return easily enough £2500 anyway
plus the £1000 saved, means I have £3500 to:
-Install the K20 on custom mounts
-Make sure cable change is working
-Have the header modified to suit
-Custom drive shafts
-Mate fuel and water systems (I can do easily)
-Wiring (based on K20 loom into my SC ECU harness should be not too hard so I can do)
I reckon that's massively doable for that money and as the car is not a daily whilst this happens I can remove the engine. Once it's located and mounts built and welded I can bring it back to finish most of the time consuming parts.
The LSD and shorter FD can be a stage 2 essentially once it's all working or as the project progresses I'll have a better handle on the costs so can just slap um in as I go.