They revised the balance shafts in the 07's, the kit will not work.

Last edited by donspecv02 (2008-12-04 17:01:55)

You rotating assembly is now balanced, the Balance shaft does nothing for the most part.  I posted pics last time this question came up, ill see if i can find them, and show you what i mean.  However, if you really want to improve the rotating assemblies balance issue, i suggest you take a look at counterweight #3.  Its the only one ive seen, on 11 B16 cranks that is Overweight.  Fix that, and throw of a crankscraper, and see what u get.

Djtorello wrote:

You rotating assembly is now balanced, the Balance shaft does nothing for the most part.  I posted pics last time this question came up, ill see if i can find them, and show you what i mean.  However, if you really want to improve the rotating assemblies balance issue, i suggest you take a look at counterweight #3.  Its the only one ive seen, on 11 B16 cranks that is Overweight.  Fix that, and throw of a crankscraper, and see what u get.

wait what... 11 b16 cranks you've seen #3 counterweight was off ? more details pls

ill take one out if someone brings me a 07

ATeamM wrote:

donspecv02 wrote:

Djtorello wrote:

You rotating assembly is now balanced, the Balance shaft does nothing for the most part.  I posted pics last time this question came up, ill see if i can find them, and show you what i mean.  However, if you really want to improve the rotating assemblies balance issue, i suggest you take a look at counterweight #3.  Its the only one ive seen, on 11 B16 cranks that is Overweight.  Fix that, and throw of a crankscraper, and see what u get.

The balance shafts are for NVH and nothing else, they cancel second order vibrations.  All QR engines are internally balanced.

This may be what your talking about but I read that its impossible to perfectly balance a 4 banger, hence the balace shaft.

The balance shafts are SOLELY for NVH and has nothing to do with balancing the rotating assembly.  It is a secondary system.  Balance shafts spin twice the speed of the engine to cancel second order vibrations with it's own vibrations caused by the long stroke.  It has no other purpose.  Only long stroke I-4's use balance shaft systems, and they are there to provide smoother operation.  The engine actually has less vibrations without the shafts, it's just that the shafts are tuned to create vibrations that directly cancel second order vibrations from engine.  If it was necessary, the B15 guys wouldn't be removing them.

Last edited by donspecv02 (2008-12-05 10:09:56)

DJ,

I have an 07 spec v. All I have installed is an Ingen CAI. Since you seem to have some expierence, what do you reccomend modding next and what brands do you think are superior?

donspecv02 wrote:

ATeamM wrote:

donspecv02 wrote:

The balance shafts are for NVH and nothing else, they cancel second order vibrations.  All QR engines are internally balanced.

This may be what your talking about but I read that its impossible to perfectly balance a 4 banger, hence the balace shaft.

The balance shafts are SOLELY for NVH and has nothing to do with balancing the rotating assembly.  It is a secondary system.  Balance shafts spin twice the speed of the engine to cancel second order vibrations with it's own vibrations caused by the long stroke.  It has no other purpose.  Only long stroke I-4's use balance shaft systems, and they are there to provide smoother operation.  The engine actually has less vibrations without the shafts, it's just that the shafts are tuned to create vibrations that directly cancel second order vibrations from engine.  If it was necessary, the B15 guys wouldn't be removing them.

I wasn't saying that you have to have them I know you can run with out them and not have a problem. That was just what I read and wanted to confirm it.