Originally Posted by dinan540
If you search bimmer forums, they argue incessantly that the CAI will not increase HP, it is a farce. But, if you combine the intake with software, manifold, throttle bodies, exhaust, your engine will breathe better and you increase the HP. The CAI will give you a cool sound. I am fan of dinan because they research the hell out of their products. You are paying for a name, but sometimes you get what you pay for.
As for VF, they make great products, but they have not been in the BMW tuning scene nearly as long as Dinan. I know of a dinan super charger on an M3 that has 100,000 miles on it. I don't know of any VF supercharger reliable lasting 100,000 miles. Plus, Dinan will warranty their products on a brand new BMW for 4 years or 50000. That takes balls, but they stand behind their product.
If you are only planning to do a CAI, save your money and don't pay for the dinan, get VF or AFE.
Whether CAI adds power or not is a huge debate.
I'm not really a fan of Dinan because I think they are way over priced. Many of the major aftermarket parts companies do a lot of research and spend a lot of money to build development labs so their engineers can do the job right. I don't see Dinan being the exclusive tuner that does their research.
I always thought that Dinan charged a lot because they had to in order to pay for the cost of CARB certification and their warranty. However, it has come to light in the last year or so that Dinan's warranty is questionable. They seem to have denied many warranty claims and have a steadily growing base of dissatisfied customers that were counting on that holy grail warranty they like to talk about. The only thing I count on Dinan for is their consistency in getting most of the products CARB certified. This is important to many CA owners. There have been dealerships that have decided to stop offering Dinan products because they had too many customers with problems they couldn't get covered under BMW warranty (due to Dinan product being involved) but then also got declined by Dinan's warranty.
Knowing that you have some sort of warranty may feel good as long as you don't need it. When it comes time to file a claim is when you really find out the value of that warranty. That's just a general truth about warranties in general, not specific to Dinan. Nonetheless, it's a truth that applies to Dinan.