Hi all,
I posted this on RAT yesterday on the subject of airboxes, airbox mods and removal and as it's more relevant to you guys I thought I'd better post it here.
I know many America and Speedmaster owners are waiting patiently for the EFI tunes and it's been a long time since we said about releasing them, but they are nearly done and it won't be long at all. But I thought you may be interested in what we have learnt about airbox mods and airbox removal with pods by way of a dyno graph.
As a reference, tune 9 is as it says, tune 6 is with a Breathe, DNA filter and full airbox mods which involved cutting out the internal baffle and cutting the bottom out of the air filter with a corresponding hole in the bottom of the airbox as this is common among owners and tune 3 is basic airbox mods with just the Breathe and DNA filter installed.
As you can see, with pods you start to gain bhp from 5,500rpm and will start to feel it at around 6,500rpm, but you do lose torque in the low to mid range. This configuration does give the most top end power as expected.
Full airbox mods were surprising as I was expecting to make decent gains in the mid range compared to just the Breathe and filter, but it was the same as with pods, mid range torque was lost below 5,000rpm. Small gains and loses are made from above 5,000rpm to the rev limiter compared to the basic airbox mods.
Installing the Breathe and DNA filter with no mods to the airbox gave the best low to mid range torque up to 5,000rpm and then as with full airbox mods gave small gains and loses to the red line. This configuration gave the best low to mid range benefits.
