| 1293 supercharged engine |
|
|
|
|
MLM Top Engine Builds
1293 supercharged A series  Click Graph to enlarge All our engines are setup on the same rolling road to ensure consistant results and to show how different engine specifications comapre, rolling roads do vary but our chosen venue Sanspeed regularly power check std cars to ensure accuracy. MLM Top Engine Builds………….. When we build an A series engine for performance our road engines are always built with modest horsepower to enable the owner to enjoy his/her investment, its well known that any A series tuned to over 85bhp and units built for high rpm tend to have very short usable life, with not much re-usable at rebuild time, we combine careful to attention to use, compression ratio and cam choice to give the best reliability so you wont find crowd pleasing power figures here on our road going engines but you will find very drivable and torquey units! There are some exceptions of course but this is of course down to application, we can offer a 130bhp 8000rpm spec if you plan to go racing or sprinting, or 100bhp reliable rally specs. Supercharged 1293cc As part of a clubman estate rebuild in 2007 we where asked to put together a spec for a supercharged engine for it, a lot of road mileage was envisaged so again we we applied our ‘less is more’ ideals to the engine power to ensure some mileage! We would build an engine/transmission and fit a Vmax supercharger kit that uses the eaton m45 blower. Car already fitted with very tired 1275 which was Removed at body stripdown, Donor unit supplied by customer for special build. Gearbox, stripped to bare case, gearset cleaned inspected and re-built into fully cleaned case with all new roller bearings, needle roller bearings, shafts, differential replaced with upgraded non LSD 4 pinion unit 2.9 final drive ratio. Drop gears cleaned and inspected, new idler gear and input gear bearings fitted, primary out put gear bronze bearings replaced. Drop case and outer bell housing cases sand blasted and re-painted. Clutch: Safely lightened flywheel and backplate, fitted with AP racing ‘Orange’ diapragm, AP racing friction plate, whole assembly balanced and spring pressure oprimised. When assembled the the clutch actuating gear was also replaced, release bearing/ clutch arm, top and bottom plungers and clutch slave cylinder. Engine: Special build to allow use of VMAX Scart Supercharger conversion. Block stripped cam bearings, oil gallery plugs, water plugs removed, chemically cleaned, and rebore to next oversize +20 thou = 1293cc. Crank shaft reground to next undersize –10thou and sent for hardening treatment. Then checked for straightness and corrected. Block fitted with new cam bearings and new mini spares ‘mega’ pistons +20 fitted to rods, engine ‘dry’built installing crank shaft rods and pistons with no rings to check piston deck height, measure, and then strip engine to have block face skimmed to set compression ratio to 8.50.1 All parts cleaned again then re-assembled rod bolts replaced with ARP competition bolt and nut kit, Crankshaft installed with vandervell quality bearing shells, crank thrust measured and appropriate size thrust washers fitted. Block fitted with new oil gallery plugs and coolant plugs. Morspeed phase 2 camshaft installed with new followers, duplex timing gear and tensioner, cam timing checked and adjusted with 8 degree off set key. New oil pump fitted. Specific custom made alloy front pulley fitted with fan belt and supercharger drive. Cylinder head: Std unleaded 1275cc 12G940 casting, inlet and exhaust ports cleaned up for improved flow, combustion chambers ground out to suit Compression Ratio and balanced, new road spec guides and valves installed with heavy duty 180Lb valve spring set. Engine built up onto gearbox, along with new water pump engine driven fan, recon alternator and starter, New rover electronic distributor and coil and gen rover HT leads. ACDodd custom advance curve. Cylinder head installed on engine with stainless steel 9cc decompression plate and two BK450 head gaskets to achieve desire compression ratio for supercharging, head secured with ARP competition head stud and nut kit. Engine installed in car with new main lower engine mounts, new heavy duty steady bushes to upper and lower mounts, and specially made additional right hand upper steady. New LCB manifold covered with heat wrap installed along with new estate maniflow exhaust system medium bore, supercharger main kit installed which consists of BMW cooper S supercharger mounted on custom made inlet manifold, fitted with custom made belt tensioner, custom made air inlet tube fitted to supercharger, induction consists of a rebuilt metro hif44 carb installed to o/s/f of engine and fitted with a K/N tapered air filter, Water system upgraded with mini spares 2 core ‘super cool’ radiator, new hoses throughout and additional front mounted radiator fitted along with electric cooling fan. Oil system also upgraded with the fitting of a 10 row oil cooler fitted in lower front grille area, plumbed in with mocal oil hose and take off for oil temp gauge. Fuel system upgraded with new high capacity facet fuel pump and fuel pressure regulator and filter. After running in for over 1000 miles we went to the rolling road for setting up AC tried a few of his custom needle profiles, we wanted 100bhp and we got 107! With a whopping 110lbft torque at 3500rpm combined with the high gearing this car is a superb long distance cruiser at high speeds with overtaking not a problem! Our demands for only 100bhp has paid off as the car has covered 10,000 miles in a short space of time and has suffered no major problems apart from a small oil leak and a cracked exhaust manifold which is to be expected on a modified engine, after careful checking we envisage a thorough strip down and inspection at the next 10,000 miles going to show a modified A series still needs careful looking after!
|
