Nick-lt1

iTrader: (1)

Someone told me that a fast 78 could be converted to a 90mm if you bought the 90mm upper? Is the true? Thanks

sscamaro1384

iTrader: (163)

as far as i know and have read it is true thats why the upper shell is over 400 dollars new but ive seen them on here and ebay for like 150-200. i have the 78mm and will be doing this when i add heads/cam. u also need the 90mm Tb to maximize power gains.

NAAllTheWay

anyone know if the rest of the intake is identical tho other than the top shells?

DrkPhx

iTrader: (15)

You only need the upper shell to convert it, the lower shell is the same. You should also get a new gasket that seals them together as well.