hi i am new to this forum by the way but my reason for posting is i have a 2007 ram 1500 with the 5.7 hemi with a true dual exhaust and cold air intake, and it was fast until i put 33 inch tires on now im lacking horsepower and speed, what mods or changes can i do to gain power?

 

Superchips 3815...

I sold mine, and when i put 33's on my truck, I bought another one.

 

The superchips will help some, to be sure and it's a natural progression to get one after exhaust and CAI. But the way to truly get the power that you are making to the rear wheels more effectively is to regear to 4.56 gears!
It's a super mod and one that is really needed as you go up in tire size and especially if you have the heavier 20" wheels. You effectively change your gearing as you increase the diameter of the tires you are running. If your truck came stock with say 31.5" tires and the cheazy 3.55 gears and you increase your tire diameter to 33" you are effectively now running with 3.38 gearing.
Optimum gearing for a full size truck for a good balance of performance and fuel economy is between 4.10 & 4.56. With my stock tires I was just under that as I had the upgraded factory 3.92s. When I lifted and went to 35" tires, I effectively changed my gear ratio to 3.52, really poor gearing (which is why nobody likes the stock 3.55s) and it felt big time underpowered. A change to 4.56 gears brought my effective gearing to 4.29 and the performance difference was night/day...

 

since my truck is a 4 wheel drive wouldn't re gearing be expensive?

 

Depends on what you consider expensive. I got re-geared with 4.56's front & rear, master install kit, Auburn LSD, fluids, labor & a check up at 500 miles with fluid change for just over $1400 after tax. And would do it again in a second, as I'm sure most who have re-geared would.
I'm actually surprised you feel that much of a drag with just 33's. My guess would be you've got the much less desirable 3.55's as opposed to the 3.92's...