where can i get a upgraded valvetrain kit for a 07 type s bigger valves better springs and retainers and also get the head ported and polished anyone know who does this

 

Below is for the J32. Same as the J35?

Supertech Spring and Retainer Kit!!! (click here)

 

NVA-AV6 (Paul) can do the work. I believe he uses KMS springs & retainers. I'm not sure on the larger valves though.

 

No need for stiffer springs, retainers, and keepers if you're not exceeding the factory rev limit. It would be a complete waste of money. The only exception would be a larger cam and I've only seen one company. Even their street version is huge and would not pass emissions.

Head porting is something you can have done at a local level as long as you find someone good.

Every engine series' heads are a little different. However, any good head porter will run a mill and clean up the bowl area, smooth the short side radius, and do a conservative port job. You don't have to know the engine series that well to get 85% of the advantages of a full expert race port for half the price. The last 15% is what will cost you the big bucks and a lot of searching for the right person who has done many sets of these heads before.

I've heard Paul's work is very nice.