SeanDezart
Well-Known Forum User
Depends what happened next.....strike 1, strike 2....Would this be classed as a bird strike?
I have the variable legth Emerald trumpets (thanks Pete and Steve) so will be getting it all just right with my Efi.
Depends what happened next.....strike 1, strike 2....Would this be classed as a bird strike?
DOH! thanks for the correction Pete! This is going to sound like an “oh yeah, pull the other one” moment, but I did know that - not sure what I was thinking putting it the other way around above... being a dumbass I suppose!"Short story - shorter trumpets/inlet tract length equals less top end but more response across the range/lower down; long trumpets - maximises top end but less low end performance."
Wrong way round!!!!
Correct answer is.......
"The very short answer to the final question is that short, wide inlet runners move the torque curve up the rev range whereas long, narrow runners move the curve down the rev range. BUT - there is a whole lot more to it than that. The effect is caused by 'pulse waves', waves of relatively high and low pressure in the runner."
For more info see Dave Walkers article on the development of his adjustable length trumpets......
Here's a dyno pic from 2012.
One of the big differences between the red run and the black run is that black has the air box on.
View attachment 32471
That was pre ratchet straps. They're worth another 100bhpWell the proof is in the pudding, amazing what a fibre glass box and a couple of ractchet straps can do!
For the red dyno run, the lid of the air box was off, so no filters (but ram tubes were there)What filters did you have on before Jon or none at all ?
Hi John, out of curiosity, did you need re-jet when installing a cold air intake?Here's a dyno pic from 2012.
One of the big differences between the red run and the black run is that black has the air box on.
View attachment 32471
if you look at the period rally/hampster cage airboxes, they're quite similar to what you have there, maybe a little deeper?