I just added a set vance hines dual oval slasher. Omy they sound great!!!! I have a 08 Ultra classic. It is completely stock except the V&H slip ons. Do I need to add a tuner? Harley parts guy says no I will not have to add a tuner till I change headers and air filter. But the V&H box says its time to add a fuelpack tuner. Thanks for your help

 

Well I've been tossing the ole time to buy some slip ons around now for two years. Been checking several and think I like the sound of the V&H Twin Slash Ovals the best. My ride is an 09, and stock. I need to still pick a high flow air filter to replace the stock football air cleaner. Been looking at the SE Extreme Billet Ventilator, but have not really made a selection yet. Kinda like the chrome SE Heavy Breather also, if it doesn't drive my right leg crazy. Head pipes I'm leaving stock right now. I have been told that even adding just slip on exhaust we should retune the bike. Since it's been almost 5 months since your post, what did you come up with? Curious to know!

 

I just added V&H Oversize Raiders with no tune to a stock M8 engine and all good. Both V&H as well as as J&P Cycles told me no tune necessary for just slip on's. I get no decel pop at all. It runs and sounds great. Will do the tune once adding the air cleanerr.

 

If you don't get popping on decel I think you're ok. I'm not familiar with the 08 efi system but I got a good tuner from Fuel Moto an reflashed my bike that came with V&H twin slash slipon's that were tuned with the HD street tuner an the bike runs way better with the Fuel Moto flash.