The V8 and V6 rocker balls are physically identical except for the hole in the middle. The V8 and V6 rocker arms (the old-style, non-self-aligning type) are interchangeable.
If you use the V6 balls with 10mm hole with V8 rockers they'll bolt right up to the existing 10mm studs in the V6 heads.
No need to change studs at all. I did this very mod to my 3.4. The Small Block Chev V8 rockers were a fair amount cheaper than the Comp Cams Magnum rocker set for a V6, and after 8 yrs they seem to be holding up!
Since the 2.8 and 3.4 have identical heads and valvetrain, the above parts are interchangeable between motors no problem.
Far as springs go, GM sells a set of performance springs used for more valve lift in the HT 3.4 motor. Here's the part #:
"12363215 ù Valve Spring
This valve spring is used in the new 3.4-liter engine conversion package
(P/N 12363230) and designed for moderate performance usage.
Manufactured from chrome silicon wire, this spring produces 105 pounds of
seat pressure at an installed height of 1.70" and 296 pounds open pressure
at a height of 1.20".
Technical Note: Use with retainer P/N 12363216."
Here's a good thread on valve spring options:
http://www.4x4wire.com/forums/showflat.php?Cat=&Board=UBB86&Number=900873Anyway, a shame you had that $$ exhaust done last year, they probably used the original 1-7/8" piping too. Probably would've cost very little more for larger diameter at the time of replacement.
Hate to say it but it's difficult to achieve significant gains from improvements made under the hood (especially with a 2.8 in there) if the exhaust isn't first 'uncorked'.
As per your other post, the injector pod spacer is a nice economical way to get a bit more airflow.
And the MSD Blaster coil is the same one I have on my 3.4. It was easy to install, bolted-in just like the stock one.
Can't say it made a huge difference but certainly has more spark energy than stock and besides, it's Red!! Get some nice heavy-duty red wires to match and it'll look sweet!
Cheers.......ed
