FVD throttle body replacement 71mm
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Hi Colin,
Thanks for your indepth contribution to this thread. Very much reminds me of a David Vizard quote: "I don't have opinions....just a flow bench and a dyno".
One question arises:
<<completely limited by the shape and turn of the intake rubber elbow; by substituting this for a large radius bend I managed to find another 4-5hp and equalised the performance with either the 68mm or 70mm throttle body. At the time I considered making a custom carbon intake pipe to replace the stock elbow, however further tests showed that we could achieve similar results with a longer intake pipe which stabilises the flow after the filter & builds up more velocity in the tract before the elbow. With the revised long pipe design we found 3hp & reduced the difference between stock & 70mm TB to around 1hp.>>
What would have been the outcome of combining the two e.g. elbow + intake pipe? ;-)
Cheers,
Harald
Thanks for your indepth contribution to this thread. Very much reminds me of a David Vizard quote: "I don't have opinions....just a flow bench and a dyno".
One question arises:
<<completely limited by the shape and turn of the intake rubber elbow; by substituting this for a large radius bend I managed to find another 4-5hp and equalised the performance with either the 68mm or 70mm throttle body. At the time I considered making a custom carbon intake pipe to replace the stock elbow, however further tests showed that we could achieve similar results with a longer intake pipe which stabilises the flow after the filter & builds up more velocity in the tract before the elbow. With the revised long pipe design we found 3hp & reduced the difference between stock & 70mm TB to around 1hp.>>
What would have been the outcome of combining the two e.g. elbow + intake pipe? ;-)
Cheers,
Harald
I did make a one-piece pipe with two long radius bends in aluminium to initially test my idea and this is how I found the 4-5hp. The problem with this design is that it was complicated to make because I would have to incorporate the breather pipe & idle valve stubs and furthermore fitting it was a pain. In the end I simplified the design to the one shown and achieved 70% of the result for 25% of the cost, so it was a commercial no-brainer as to which one we make.
The pipe will only fit a Motec equipped car which runs Alpha-N & MAP (without an AFM of any description), sold as part of the 9m Motec package, it costs £325 with K&N filter & support brackets.