Hi all, This is part me thinking out loud and part me being inquisitive but I'd appreciated your thoughts...
I've a '67 Mk3 Spitfire which I've been slowly doing up over the last 24 months or so. Its got a rebuilt GE 1300 engine with a fast road cam. I've just had it converted to Efi - as in literally just and as I write I've not yet picked it up but the tuning co have rung through the rolling road figures....
Before i tell you the results I ought put my thoughts in perspective; I'm not building a race car but rather I want a quick, fun road car and I occasionally think doing the odd hill climb might be a great way to spend a day out. There seems to be a lot of internet talk of 100bhp 1300's being but an afternoons work, so with that figure in my mind I got busy.
So my engine spec is;
GE small crank engine , plus 20 pistons, minus 10 big ends and mains tri metal bearings, pistons and rods balanced, New timing chain, tensioner oil seals gaskets , uprated oil pressure release valve. new swept back oil pump, lightened flywheel (approx 5 kg ), TH5 fast road cam with new followers, big valve head with competition high lift twin valve springs lightweight alloy caps.
I'm pretty sure converting to Efi was never going to increase the hp, but I cant decide if i'm disappointed or If i'm looking at a piece of paper rather than waiting and feeling through the seat of my pants;
80bhp and 95lbsft @ 5100.... at the flywheel.
i'm no expert but wikipedia suggests the car would have left the factory with 75bhp and 75 lb-ft @ 4000rpm [albeit 53 years ago], so my mods seem to have given me 10bhp and 20 lb-ft.....but then look again and thats bhp +12% and torque +28% assuming triumphs figures were also quoted at the flywheel.
Thinking out loud, those percentages dont actually seem too bad and doing the same calculation to get to 100hp would mean an increase of over 33%; I'm reasonably sure the internals could take 100hp but to get there would seem to be significantly more than the proverbial afternoons work?
So am i looking at a glass half full or is something not seeming quite right with my engine?
Many thanks