[gibsonj4]

Once again I will ask this since I got no response. Has any1 had a P&P and/or a 3 angle valve job done to their head? If so, what gains are made from this? I am talking about Port and Polishing the combustion chamber. I realize that tuning would get the most out of this mod but would the new airflow pattern disrupt the ecm? Would it run lean because of the new air flow?

 

[Maven]

This is what the Patriot Stage I head is, a ported/ 3 angle stock head. same with the GMPP Sportsman head.

There definitely gains to be made with the use of a ported head, there is actually very little advantage to the larger valves of a StageII head on a naturally aspirated engine.

Problem is an '07 L61 head would pro'ly have to be custom, I dont know if anyone offers that head available preported yet....(07 is different from the 00-06 heads)

 

[gibsonj4]

I was thinking going to a local machine shop and having it ported to the same specs as the patriot stage I or II as well as the 3 angle valve job. The heads are different on the 07s. It seems like my car is the redheaded step child of the cobalt family haha. it's more of a test for the AEM unit I'm purchasing. I wanna use it to tune that and eventually this summer the GT Tuner kit from garrett.

 

[Maven]

Its not the redheaded stepchild, LOL...its just got the new style head, its not like its a one year only bastard, its just not the same as the early ones . If a shop can port the old head they can port yours, port/valve wise they are virtually identical, its just that 00-06 doesnt use a cam sensor, and has coilpack ignition so you cant use that on your 07 without serious mods to the computer(swap to the old type) The head would bolt on and run if it could, its just not compatible with your ignition and fuel injection system design. There'll be 2nd Gen L61 stuff, just wait.

 

[Scoony]

is this being made for the 06' 2.4l also

 

[gibsonj4]

What are the gains to be made with this mod with tuning?