rocker arms...

[ericjon262]

I was in the junkyard today and stumbled across a LZ4 in a G6, and I noticed the rocker arms sitting on the bumper, so I grabbed one and brought it home... some of the pics suck, I'll get better ones later...


















as far as I can see, the main differences are in the pedestals, not the rocker itself, it also appears as though any competent machinist could make changes to the pedestal of the 3500 rocker to fit the LZ4 rocker.

the LZ4 rocker is also 0.5 oz lighter than the LX9 rocker (5.2 oz vs 5.7)

I have not measured the ratio of either rocker.

going by looks, the LZ4 rocker looks much stronger, this may call for a test fixture...

[Mars]

they are 1.6 vs 1.7 and by the looks of it, you should be able to swap the pedestals. I'd like to see someone try this...

[ericjon262]

they are 1.6 vs 1.7 and by the looks of it, you should be able to swap the pedestals. I'd like to see someone try this...

the peds swap no prob. I'll throw the one I have on the mock up motor and see how it fits.

[3400-95-Modified]

If it works I'll be buying a set... 1.7 will be nice to have!

Nevermind, Just found a set for $35... SOLD! lol

Also seeing that Comp says these fit a G6 motor??

http://www.ebay.com/itm/Competition-Cams-1605-1-Ultra-Pro-Magnum-Rocker-Arm-/310595014680?pt=Motors_Car_Truck_Parts_Accessories&fits=Model%3AG6&hash=item4850e7d018&vxp=mtr

They have 7/16 stud and 3/8 stud in 1.52 or 1.6 ratio... Not the 1.7 that your saying is the stock 3.5L Mars... Why would they offer that? And if the pedestal swap works then why can't we run these 1.6 full rollers?

[Purple pit]

So did I read that right? 23 each and there are only 10 of them?

[Superdave]

hmm.. i could use a little more intake lift for sure.. Might run into coil bind with my springs though.

[ericjon262]

If it works I'll be buying a set... 1.7 will be nice to have!

Nevermind, Just found a set for $35... SOLD! lol

Also seeing that Comp says these fit a G6 motor??

http://www.ebay.com/itm/Competition-Cams-1605-1-Ultra-Pro-Magnum-Rocker-Arm-/310595014680?pt=Motors_Car_Truck_Parts_Accessories&fits=Model%3AG6&hash=item4850e7d018&vxp=mtr

They have 7/16 stud and 3/8 stud in 1.52 or 1.6 ratio... Not the 1.7 that your saying is the stock 3.5L Mars... Why would they offer that? And if the pedestal swap works then why can't we run these 1.6 full rollers?

I think the pedestal is specific to the head, not the rocker, and the pedestals do swap no prob. I haven't had a chance to bolt one to my engine yet, but I see no reason at all they won't work. they are narrower at the front and rear, and have a shorter LOA then the stamped rockers. the fulcrums are the same width, and the slot width is almost the exact same(pedestals are the same width). I've been looking at some LSx full roller rockers that might interchange. those comps you linked to might work also.

[ericjon262]

3400-95-modified, I think those rockers you linked to would work, but they would require conversion studs and guideplates, where-as a set of LSx style rockers might possibly mount to the stock pedestal, and be available in higher ratios.

[3400-95-Modified]

Why wouldn't the comp ones sit on the stock pedestal? I guess its worth sending COMP a message asking if they designed those to work on the factory 3.5 and 3.9L pedestal if so they they would work on our 3500 and 3400 ones.

They are listed as application specific...

And yeah Dave I'm starting to wonder about coil bind myself if the 1.7's fit LOL All I can do it test and find out right?

549/603 would be pretty sweet, but I could also do just 1.7 on the intakes... but then having miss matched rockers may be a bit odd.

[SappySE107]

I seem to recall this not working, and the LS aren't the right geometry either if I recall correctly. Those comp rockers are for Chevy Small Block 265-400 cid from my search.

[ericjon262]

Why wouldn't the comp ones sit on the stock pedestal? I guess its worth sending COMP a message asking if they designed those to work on the factory 3.5 and 3.9L pedestal if so they they would work on our 3500 and 3400 ones.

They are listed as application specific...

And yeah Dave I'm starting to wonder about coil bind myself if the 1.7's fit LOL All I can do it test and find out right?

549/603 would be pretty sweet, but I could also do just 1.7 on the intakes... but then having miss matched rockers may be a bit odd.

2 reasons, 1 slot width, 2 3/8" and 7/16" are both way bigger then the 8mm bolts that hold out rockers down. the LSx rockers are already 8mm, and probably a better route then those.

[ericjon262]

I seem to recall this not working, and the LS aren't the right geometry either if I recall correctly. Those comp rockers are for Chevy Small Block 265-400 cid from my search.

I've got both(LX9 and LZ4) in my hands right now in front of me, and they both *appear*identical from the standpoint of valve contact/fulcrum. I haven't bolted one on yet, I still need to pick up at least one more to make sure there's no interference.

the main difference appears to be the pedestal, which swaps out no problem, and the LX9 pedestal top can be modified to match the LZ4 if it matters.

[3400-95-Modified]

2 reasons, 1 slot width, 2 3/8" and 7/16" are both way bigger then the 8mm bolts that hold out rockers down. the LSx rockers are already 8mm, and probably a better route then those.

Slot width I can understand... and stud size you could correct with a collar... But seeing how Ben found them as SBC rockers then it's really odd that COMP or at least someone on ebay lists them as compatible with the G6.

Let me know what you come up with Eric when you test fit them, I may have a set soon as well.

[ericjon262]

veekuusi is running SBC rockers on his 3100, if they work there they should work here. again though, you'd be best to use a conversion stud and guideplate if you go that route IMO.

[3400-95-Modified]

I know SBC rockers will work, but the point I'm making is, if the width is the same for the pedestal then why reinvent the wheel? just bush the stud hole to make it 8mm and use the factory 3400/3500 pedestal and your done. That is if the geometry is the same as well. And I'm only stating this because of the way that e-bay list was, and yes I know that's not something good to go by, I honestly don't think they would list them as "compatible" if you had to build a stud and guide plate conversion... But people do weird things on ebay.