LS7 rockers on a LS1
05-27-2009, 06:41 PM
#1
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LS7 rockers on a LS1 Hey guys ,Ive got a 6.0 LQ9 block with a turbo cam with done up LS6 heads and am currently running scoipion rockers which i think are alittle loud???I was wanting a stock style ((quiter)) rocker?Whats my best bet? Ive heard that the LS7 rocker bolts right up to the LS1/LS6 heads ?and with my twin turbo setup im wondering if the 1.8 ratio is the way to go? instead of the stock 1.7 ratio?
05-27-2009, 10:31 PM
#2
The LS7 rockers are 3mm longer over the nose and postion the rocker contact area verrry close to the edge of the valve tip, too close for comfort or reliability IMO. I have been doing a TON of research on this lately. I can't find any source for a recessed 8mm keeper/lock assembly to clear a lash cap.
If you have non stock heads with a more common valve stem diameter you may be able to source a retainer/lock/spring/lash cap setup to work for you. Your other options would be to machine the heads to lower the pedestals or do some custom work to the pedestals to get the rockers down to where they need to be for good valvetrain geometry. Then you need to address the pushrod length. You may run into issues with valve float from the increased rocker ratio.
I know Thunder Racing doesn't recommend more than the stock 1.7 ratio due to ramp rates and their ramps are only marginally more aggressive than an XE lobe. Most cams ground these days have much faster lobes than that. From the data and research I have compiled it would be more cost and time effective to buy a new custom grind cam. If you do go through with it keep us updated with your results. Good luck,
Larry
If you have non stock heads with a more common valve stem diameter you may be able to source a retainer/lock/spring/lash cap setup to work for you. Your other options would be to machine the heads to lower the pedestals or do some custom work to the pedestals to get the rockers down to where they need to be for good valvetrain geometry. Then you need to address the pushrod length. You may run into issues with valve float from the increased rocker ratio.
I know Thunder Racing doesn't recommend more than the stock 1.7 ratio due to ramp rates and their ramps are only marginally more aggressive than an XE lobe. Most cams ground these days have much faster lobes than that. From the data and research I have compiled it would be more cost and time effective to buy a new custom grind cam. If you do go through with it keep us updated with your results. Good luck,
Larry
06-08-2009, 10:36 AM
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The LS7 rockers are 3mm longer over the nose and postion the rocker contact area verrry close to the edge of the valve tip, too close for comfort or reliability IMO. I have been doing a TON of research on this lately. I can't find any source for a recessed 8mm keeper/lock assembly to clear a lash cap.
If you have non stock heads with a more common valve stem diameter you may be able to source a retainer/lock/spring/lash cap setup to work for you. Your other options would be to machine the heads to lower the pedestals or do some custom work to the pedestals to get the rockers down to where they need to be for good valvetrain geometry. Then you need to address the pushrod length. You may run into issues with valve float from the increased rocker ratio.
I know Thunder Racing doesn't recommend more than the stock 1.7 ratio due to ramp rates and their ramps are only marginally more aggressive than an XE lobe. Most cams ground these days have much faster lobes than that. From the data and research I have compiled it would be more cost and time effective to buy a new custom grind cam. If you do go through with it keep us updated with your results. Good luck,
Larry
If you have non stock heads with a more common valve stem diameter you may be able to source a retainer/lock/spring/lash cap setup to work for you. Your other options would be to machine the heads to lower the pedestals or do some custom work to the pedestals to get the rockers down to where they need to be for good valvetrain geometry. Then you need to address the pushrod length. You may run into issues with valve float from the increased rocker ratio.
I know Thunder Racing doesn't recommend more than the stock 1.7 ratio due to ramp rates and their ramps are only marginally more aggressive than an XE lobe. Most cams ground these days have much faster lobes than that. From the data and research I have compiled it would be more cost and time effective to buy a new custom grind cam. If you do go through with it keep us updated with your results. Good luck,
Larry
04-21-2010, 08:47 PM
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I finally got around to installing my HS modified rockers today ,,,,,Anybody looking for a (super low) mile set of scoipion rockers that only have 300 easy miles on them ? Im pretty sure i paid like $300 for em new 2 years ago. As most of you know ,,,,its takin me this long to finally get my setup right!But YES its got maybe 300 miles on em if that and they were just alittle too ticky for my taste and I wasnt looking to add any more HP to my ride anyways (which these will do) beings there rolller tips
04-22-2010, 09:58 AM
#6
You can also to the Comp trunion upgrade if you wanted to do it yourself. Does the same thing with replacing the needle bearings with a roller fulcrum. It will save you a little money. Be sure to check your preload and make sure that isn't the cause of the loud valvetrain as well...
Jon
Jon
