750 to 860

I am rebuilding a 1974 750GTES but due to the cost of work required to barrels, heads, conrods, gearbox etc I wondered if anyone has fitted the 860 barrels pistons and heads? I have found a 860 engine which has all the parts in reasonable condition also gearbox which I need. Just not found anyone who has done this before. Carl Harrison is building the engine for me and suggested this, but would be good to hear from any others who have done this mod. I plan to use the roundcase engine casings.

I know it has been done, but you’d need to bore the crankcases to get the bigger liners in.
The biggest issue will be with the con-rods. They are longer on the 750, so if you used standard 860 pistons they’d hit the heads. Alternatively, rebuild the crank using 860 rods. A spacer under the barrels would raise the head heights to give the clearance if you used 750 rods, but you’d be best off talking to someone like Tony Brancato for some sensible ideas.

Thanks for the info Spaggy, I now have the 860 motor hoping that the gears are in good condition to offset the cost of the engine, Carl is confident it can be done but it would be good to have contact details for Tony Brancato all advice appreciated.

Tony Brancato can be found here:
Unit 8a, Monument Business Park, Warpsgrove Ln, Oxford OX44 7RW

Phone: 01865 891203, but be prepared for a long conversation. Make your coffee first! :smiley: