How much room should there be between ITB trumpet and airbox?

[Cro]

Anyone know if theres a minimum or optimum distance between the end of the trumpet and the beginning of the airbox?

 

[Jonny1*2]

How much distance you got? I've presume so long as they're not sucking the box (giggity ), they should be fine.

 

[Cro]

Lol, thinking about changing the box I have a 60mm backplate, 90mm trumpets currently so 30mm protruding.

Thinking about a 65mm front plate so 35mm clearance to the front of the box... but its not flat so could be slightly under 30mm in some places

 

[Jonny1*2]

I'd be suprised if 5mm more would make much difference, but worth a try. you'd be able to tell if it was choking itself. would it not be easier to get smaller trumpets?

 

[sideways danny]

30mm is a fair clearance. You can even see improvements in places by having a baffle plate closer to the trumpet mouth. the rules are not hard and fast though, it has to be experimented with to find what's best. I would stick with what you have in honesty

 

[Cro]

Its the difference between using the usual sausage filters and moving to a cold air box similar to burps though danny

 

[sideways danny]

with those pipercross boxes, it's more important getting the distance right. Trialed one in a very tight space and because the box was too close to the bell-mouths it was a big restriction, but a sausage filter swapped on was a lot better. I think it was 18bhp difference we saw. With decent clearance on another vehicle, there was no power difference. A box is generally a good idea for wet weather, and noise limitation

 

[Cro]

I'm probably just going to have to try both on a rr then. For testing should there be a filter on the airbox Danny or fine for that short time just sucking in from the side?

 

[Tom@JMS]

From experience I'd want a lot more than 30mm between the face of a trumpet and the back wall of a single inlet airbox.

 

[Cro]

What did you try that makes you say that Tom?