I'm not running one currently, but I have had them on my own cars and installed them on customer cars. They're usable on the street, but you do have to spend some time getting them dialed in and tuned properly....then keeping the carbs in tune once you get things working right.
As a general rule, tunnel rams are designed to operate at a higher rpm then a single carb, so cam selection should also be for higher (3500 to 7500) rpm range... Then, if you're running an automatic tranny, it's going to take a higher stall converter to allow the cam to work properly.... They will work ok at lower rpm's, but there are a ton of single four barrel carb and intake combinations that will work better then a tunnel ram at street rpm levels. All that said, the kewlness factor of a tunnel ram is always high, whether or not it's worth the extra expense and effort would have to be a personal decision.
Finally, tunnel ram and fuel mileage shouldn't even be used in the same sentence!!!!
As a general rule, tunnel rams are designed to operate at a higher rpm then a single carb, so cam selection should also be for higher (3500 to 7500) rpm range... Then, if you're running an automatic tranny, it's going to take a higher stall converter to allow the cam to work properly.... They will work ok at lower rpm's, but there are a ton of single four barrel carb and intake combinations that will work better then a tunnel ram at street rpm levels. All that said, the kewlness factor of a tunnel ram is always high, whether or not it's worth the extra expense and effort would have to be a personal decision.
Finally, tunnel ram and fuel mileage shouldn't even be used in the same sentence!!!!