Farmer42
Club Member
I'm looking for some advice on air filters for my HS6 SU carbs. Since I swapped from the Datsun Hitachi carbs, the OEM airbox & filter wouldn't fit to the HS6 so I am using 70mm Air Ram trumpets. These are great for performance and the fuel economy isn't too bad but I am a bit concerned that without a filter, it could suck in unwanted debris & damage the engine.
I have tried a couple of 1.5 inch depth round pancake filters but the performance dropped significantly and it misfired badly on revs over 2k. It appeared to be flooding the carbs with fuel due to not sucking in enough air no matter how much I fiddled with the tune up and mixture.
I was thinking of some deeper filters like the K&N filters in the link below but they are a bit pricey and I don't want to be wasting money by spending £150-200 and then have the same problems as mentioned previously.
https://www.ebay.co.uk/itm/56-1430-...rentrq:956e7d911690ac1c5d91e084ffff5e4d|iid:1
What are people running with on SUs? Does anyone know if there are filter socks that fit over the trumpets?
I have tried a couple of 1.5 inch depth round pancake filters but the performance dropped significantly and it misfired badly on revs over 2k. It appeared to be flooding the carbs with fuel due to not sucking in enough air no matter how much I fiddled with the tune up and mixture.
I was thinking of some deeper filters like the K&N filters in the link below but they are a bit pricey and I don't want to be wasting money by spending £150-200 and then have the same problems as mentioned previously.
https://www.ebay.co.uk/itm/56-1430-...rentrq:956e7d911690ac1c5d91e084ffff5e4d|iid:1
What are people running with on SUs? Does anyone know if there are filter socks that fit over the trumpets?