Ported and oversized valves, "performance" springs. Looking at $1100 for the 0331.
Buying a new Clearwater/ATK one is about $500, and you'd be up to $800 easy after porting and new valves/springs... I can't back up the extra $300 though - anybody running this head? Clegg seems to have a pretty good reputation overall, but I haven't been able to dig up much specifically regarding their Jeep tech. I was planning on running the COMP Cams 231-4 (206/214) cam with it.
"Roads? Where we're going, we don't need roads..."
Valve seats are opened up to accommodate large intake (2.0 in.) and exhaust valves (1.551 in.)
Those are probably Chevy LS1 valves so they may also use LS1 valve springs.
Look identical to my LSx stuff. I used the lightweight ls6 stuff though..same size, less weight and sodium filled exhuast. I would. Stray away from the valve size alone! Just because a heads ported & runs huge valves doesn't make it good.
Most air through the smallest hole is what your after..stock or slightly larger (sbc) stuff would be optimal for any all motor build. If turbo or something I could see the larger valves being beneficial..
My valves were turned down to 1.94/1.54 for what it's worth.
Also those chambers look mighty rough..mine are polished up to 320 grit I believe which is smooth!
X2 On the LS valvetrain. I turned my intakes from stock LS 2.00" to 1.95" and kept the exhausts at 1.55". I've been running All LS gear for valves, springs, retainers, and locks for 30k now....Works excellent. Keep in mind bigger valves don't always translate to more flow due to bore shrouding and port design.
Thanks for the replies guys - I think I'm just going to grab a Clearwater head for now and have it ported, and maybe open up the valves later down the road.
"Roads? Where we're going, we don't need roads..."
00XJ49 wrote:Thanks for the replies guys - I think I'm just going to grab a Clearwater head for now and have it ported, and maybe open up the valves later down the road.
Keep the stock intake size. Idk why my machinist didn't turn down smaller..he did have a reason though, I just forget it. Maybe 6time knows...he used the same exhaust size as me. Our 4.0s actually could benefit from a slightly smaller intake valve. The exhaust Will benefit from a slightly larger so going to a ls1 exhaust valve would be cool..just a thought?
Actually our engines don't benefit from larger exhaust valves than stock unless you unshroud them and enlarge the valve pockets to match. You can go to larger intake valves without shrouding issues but the valve pockets still have to be opened up to match.
Cheromaniac wrote:Actually our engines don't benefit from larger exhaust valves than stock unless you unshroud them and enlarge the valve pockets to match. You can go to larger intake valves without shrouding issues but the valve pockets still have to be opened up to match.
To expound upon my last reply, I was planning on getting the Clearwater head and port matching to the manifolds. However, after doing some more reading on the topic...
...it looks like this can turn into a minefield, and the ports on both sides should be pretty darn close already. I'll do the tracing paper check, but unless there's a glaring difference, I'm just going to go with the new head as is (minus springs for new cam). I believe the money I'd throw at any grinding could be better spent elsewhere...
"Roads? Where we're going, we don't need roads..."
