hi there. has anyone experiences of changing the stock exhaust on a Hyper 821 to the Termi high-mount (the road legal one, not the racing) I read somewhere that it takes away quite a lot of the engine brake. I am deciding whether to buy it with or without it, and not sure I can test it beforehand, why I am asking,,, is that true? other pros' and cons of the high termi? thx
It shouldn't change the amount of engine braking unless it's dialled out when the ecu is reprogrammed for the exhaust. Engine braking is a by product of the compression ratio of the motor, no exhaust would change this.
I just found some guy in a forum that said there was a change in the "release", and he mentioned most of the engine braking went away after installing the termi... anyone in here can share their experience with swapping to the high termi?
As 1037sps has said engine braking is a function of the compression stroke on a closed throttle. The free flowing exhaust simply allows the products of combustion to clear away more quickly when the exhaust valve is open. Ducati race engines can use 50 degrees of overlap when the inlet and exhaust valves are open at the same time which can affect engine braking. The new generation Ducati road engines are more like 12 degrees of overlap. Modification of the ECU does not change the valve timing so, no you will not lose engine braking by fitting the Termignoni exhaust. Andy
You can change valve timing though. So on a point of interest will the new VVT engine have variable engine braking as well..?
Yes because you will always have a compression stroke where both valves will be closed and with being off throttle there will only be a very small amount of fuel injected. The engine may be VVT but you are still only talking small variations for optimum road performance not the extremes of the track. Andy
