LS9 Heads on a ZL1 - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

Kevin C-ZL1 · 01-21-2020, 02:54 PM

Has anyone had any experience using LS9 heads on a ZL1 LSA engine? Any problems or anything I should be aware of? Thanks!!

blake-b · 01-21-2020, 03:29 PM

They will bolt right on. As far as I know, all parts are interchangeable (valves, springs, etc). There are multiple threads on this on LS1tech.

LS3/LSA/LS9 have the same architecture (for the most part, the LS9 has a 'wing' which gets machined out if CNC is done) and LS9/LSA is a little beefier than the LS3. LS9 uses 12mm bolts while the LS3/LSA use 11mm bolts so the bolt hole in an ls9 is 1mm bigger. Math!

The big difference is the material used to make them. Different types of aluminum. LS9 uses the most superior grade. LS9 > LSA > LS3

LS9 and LSA might even be made of same material. I can't find any specs for that at the moment.

There is a thread on LS1tech where Lou from LG cut the heads apart and noted how easy or difficult it was for each. I found the thread and there were no LS9 heads cut but there was LSA and LS3.

Lou cuts heads

RobZL1 · 01-21-2020, 04:44 PM

You can bolt them on, but most recommend to do the valve guides before doing so.

Both LS9 and LSA heads are rotocast from A356-T6.
Both LS9 and LSA have the swirl wing.
LS9 have titanium intake valves with lash caps, LSA is hollow stainless
LS9 have sodium filled exhaust valves, LSA is solid stainless

01-21-2020, 02:54 PM	#1
Kevin C-ZL1 Drives: 2015 ZL1, 2015 Z28 Join Date: Dec 2018 Location: Southern NH Posts: 297	LS9 Heads on a ZL1 Has anyone had any experience using LS9 heads on a ZL1 LSA engine? Any problems or anything I should be aware of? Thanks!!

01-21-2020, 03:29 PM	#2
blake-b Drives: 2009 ZR1 Join Date: May 2010 Location: KCMO Posts: 3,205	They will bolt right on. As far as I know, all parts are interchangeable (valves, springs, etc). There are multiple threads on this on LS1tech. LS3/LSA/LS9 have the same architecture (for the most part, the LS9 has a 'wing' which gets machined out if CNC is done) and LS9/LSA is a little beefier than the LS3. LS9 uses 12mm bolts while the LS3/LSA use 11mm bolts so the bolt hole in an ls9 is 1mm bigger. Math! The big difference is the material used to make them. Different types of aluminum. LS9 uses the most superior grade. LS9 > LSA > LS3 LS9 and LSA might even be made of same material. I can't find any specs for that at the moment. There is a thread on LS1tech where Lou from LG cut the heads apart and noted how easy or difficult it was for each. I found the thread and there were no LS9 heads cut but there was LSA and LS3. Lou cuts heads Last edited by blake-b; 01-21-2020 at 03:43 PM.

01-21-2020, 04:44 PM	#3
RobZL1 fo'shizZL1 Drives: 2017 ZL1 Join Date: Aug 2017 Location: ATL Posts: 1,281	You can bolt them on, but most recommend to do the valve guides before doing so. Both LS9 and LSA heads are rotocast from A356-T6. Both LS9 and LSA have the swirl wing. LS9 have titanium intake valves with lash caps, LSA is hollow stainless LS9 have sodium filled exhaust valves, LSA is solid stainless __________________ 2017 ZL1 M6 Black \| Maggie 2650 // 103TB // Big Gulp Past Rides- 2014 ZL1 M6 Red Hot \| Tons of mods 2004 CTS-V M6 Silver \| Many mods 1995 Corvette M6 Torch Red \| A few more mods 1992 Camaro M5 White \| A few mods