First off, thanks to Nick @ NA Motorsports and Mike @ Forge for helping me out with the purchase and the install.
I bought these valves because of all of the positive reviews found on e90post. O-cha especially convinced me with his review.
I installed the Forge Diverter Valves about two weekends ago and I feel like I have developed a good first impression to share with you all. First off, these things are HUGE compared to the stock diverter valves. I'll try to take a picture for comparison, but these look way over-engineered compared to the stock diverter valves, making them almost look like something from a kid's toy. Everything felt very solid, from the hoses and clamps to the valve itself.
Installation was a little difficult for me, but I am a noobie DIYer so it could just be my lack of skills
. In the instructions, it did not mention removing the plastic cowl, but I did to make it easier to access the back hose clamp on the intake.
I ended up finding out that the Forge valve and the stock valve were not the same height, and because of that, the hose could not be routed the same way.
In the end, I routed the hose underneath the intake to connect it to the new valve.
I also ran into what seems like a glued on vacuum hose.
I wasn't able to pull it off the first time I tried to install it. A week later, it loosened up and I was able to finally pull it off and finish the install.
Here's a few pics of it installed (angles are a little bad unfortunately):
The front hose was a little long :iono:
Nick and Mike said that I was one of the first to try this out, so they did not know what to expect as the kit was made for the 335i. If I were change anything, I would say to include an extra vacuum hose line in case the person wasn't able to get their's off, and to make the back diverter valve hose a little longer to give it more slack.
Impressions:
Because I have no power mods on this car, Nick recommended that I use the green springs included in the package. This is stated for 5psi-15psi. Initially, I found that the car was trying to adapt to the new valves. It was a little jerky at first, like it didn't seem like it knew what to expect yet. After awhile, the response started to feel much better. The power feels like it comes on much more linearly now, whereas before, there seemed like there was hesitation. Partial throtttle response is definitely improved here, and I feel like I'm much more in control with this car.
Conclusion:
I bought these valves in anticipation for more power mods in the future (tune, plus other bolt-ons), so I was not expecting much. Instead, I found the car to become more lively and much more responsive! I didn't expect to find any hp gains, and I don't believe there are any, but for drivability, it's much improved. Thumbs up to Forge :thumbup:!