Jacko wrote:Thanks Ben that’s great, my M52 will become a 3.0ltr at some point anyway but not sure on the length required. Is it true that the longer they are = more bhp and the shorter they are = more torque? I'm measure my Tbs tonight as well - restriction may be the engine bay itself anyway.
How did you calculate the length of yours?
Shafts is about the going rate it would seem, spoke to a few companies on the subject. Group buy would lower the cost though. Are you using a E12 diff?
Yes E12 diff (Welded).
I haven't decided on the final length of my runners yet. It will be adjusted with the length of silicon tube I go for.
General rule of thumb is the shorter the runner the more power higher up the rev range. And the longer the runner the more torque in the midrange.
However that isn't always true for different engines/cams/exhaust/head/valves etc.
We tried 3 different lengths when setting up our D-Type Jag on TB's. Didn't really make that much difference to the curves on that engine. (think it was none, 60mm, 90mm, 120mm). went for the 120mm mainly to match the cars original intake length and for the looks. Its approx 350mm from the head face to the end of the trumpets. So really 60mm trumpets only decreases the overall length by 17%.
Ben