fiat 131 twincam 1600cc engine,will not rev over 4000rpm. any ideas?
hi i have a blue print 1600cc 131 twincam fitted in my mk1 cortina,im sure the engine is around 1976ish.
On first test run i noticed it coughs & splutters badly on full throttle,If i drive it (normally) without holding it in the gears it drives fine,
Iv had the carb off cleaned out & refitted, re-checked timing,ect but i cant seem to stop it from doing it, please help!!
Re: fiat 131 twincam 1600cc engine,will not rev over 4000rpm. any ideas?
If the carb is ok after being overhauled then look into the ignition side of things. If it has points check their condition and gap along with the condensor.
Also check that the coil is OK. The spark may be weak when the engine is pushed hard. This is when weaknesses often show up due to higher engine speed and higher combustion pressures.
Re: fiat 131 twincam 1600cc engine,will not rev over 4000rpm. any ideas?
Hi All
If you are running side draught 40's have you uprated the fuel pump to keep the fuel supply up to the extra demand, and if you have does it run with a regulator or not.
Also when you say the timing is correct do you mean the camshaft timing or ignition and are you setting the timing to a fiat manual/haynes manual or the specification designated by the blueprinted engine rebuilder.
Re: fiat 131 twincam 1600cc engine,will not rev over 4000rpm. any ideas?
How's the mixture on the carb? Many old cars are set too rich -an indication is the colour of the inner rear exhaust- it should be a dull grey not dark, which usually shows the car burning oil (weak compressions) or too rich fuel mixture. If it's too rich at high speeds it will choke up and not breathe correctly at high revs, just a suggestion
Re: fiat 131 twincam 1600cc engine,will not rev over 4000rpm. any ideas?
hi,
i think i may have the wrong coil fitted because iv put a plug in one of the ignition leads and has a bright spark under 3800rpm then over 3800-4000rpm the spark fades out to no spark at all.
iv found out it has the later type dizzy just before they changed to electronic ignition,with the long splined shaft, single screw for the points, and a resisted rotor arm.
would anyone know if it should have a resisted coil ???
would a lucas gold sports coil do the trick??
Re: fiat 131 twincam 1600cc engine,will not rev over 4000rpm. any ideas?
Another thought Aaron, are you getting enough air into carby, (have you done some mods here), and is the exhaust getting out ok, (again have you done some mods on the exhaust side of things). Gerry
Re: fiat 131 twincam 1600cc engine,will not rev over 4000rpm. any ideas?
Have you checked that both chokes on the carb are opening? If one is vacuum operated (on older 1600 T/Cs they are) it maybe that there's a fault in there and it isn't.
