chappers1.3
08-01-08, 02:36 PM
Been reading aroud on the net about intake lengths for tuning purposes as i am making my own aluminium manifold for R1 carbs, i have read that to acheive max torque at 6000rpm you need an intake length of approx 13inch from the valve to trumpet opening.
Question is - has any1 that is using a set of DCOE carbs measured the runner length?? I know that you tune the DCOE carbs by the use of longer/shorter trumpets, what have ppl found to be optimum for the 8v engines???
By rough measurements i'm thinking from the valve head to the face of the head is about 2", i'm gonna make the manifold 4.5" total length, R1 carbs are about 4.5" aswel, then the standard trumpet is 1.5" so all together i got 2 + 4.5 + 4.5 + 1.5 = 12.5" total runner length.... which should give me Max Torque at about 6400rpm?? I think this is alittle high so i think i am going to make the manifold nearer 6" to get it down to about 5000rpm?! is this a good region to aim for??
on a RR what max torque/rpm readings are ppl getting from a 2ltr 8v at about 160bhp??
thanks guys, hope you can help.
Question is - has any1 that is using a set of DCOE carbs measured the runner length?? I know that you tune the DCOE carbs by the use of longer/shorter trumpets, what have ppl found to be optimum for the 8v engines???
By rough measurements i'm thinking from the valve head to the face of the head is about 2", i'm gonna make the manifold 4.5" total length, R1 carbs are about 4.5" aswel, then the standard trumpet is 1.5" so all together i got 2 + 4.5 + 4.5 + 1.5 = 12.5" total runner length.... which should give me Max Torque at about 6400rpm?? I think this is alittle high so i think i am going to make the manifold nearer 6" to get it down to about 5000rpm?! is this a good region to aim for??
on a RR what max torque/rpm readings are ppl getting from a 2ltr 8v at about 160bhp??
thanks guys, hope you can help.