I just recieved my heads in the mail. They are bare casting that need full valvetrain. I was wondering what upgrades or mods could be done while I have the bare castings? Im going to get them checked out at a machine shop to insure that they are good to use but what else should I have them do? Im running an LPE 211/219 cam on a 350 1pc rms block with an LT1 rotating assembly. Compression should be around 10:1 with the 58cc on the heads. Any input is appreciated.

 

Manley valves, and good valve springs.

 

These heads flow very well with porting and make good power and torque.
The hot set up is to use the 2.00" x 1.56" LT-4 sized valves in these heads.
This is largest recomended valves to use on the stock valve seat inserts.

 

Thank you for the recommendation.

Manley 10721-8 and 10722-8 are our street flow series, 1.94"/1.50" with narrow stems for more flow. They will drop right in and work with any street engine without a power adder. If you're going to run nitrous or a turbo you'll want to step up to our severe duty series of valves.

We do make 2.00"/1.56" valves but I have not heard of those sizes working with the stock valve seats. I do know those are the largest valves you can use with these heads, and they are not a direct drop-in, but I have no idea what is required to make those work. 2.02"/1.60" will not work in any way.

You can also use Manley 22410-16 springs and 23652-16 retainers, which will be good for cams up to .550" lift. If you need locks, the 13091-16's are a good 7 degree stock replacement and work with those retainers. Add in a set of 42106-16 3/8" rocker arm studs, and you're in business.

These heads are the casting number for the L98/ZZ3/ZZ4 heads, and you can search this board for "L98 heads" or "Corvette heads" or "ZZ4 heads" to read about the 3 major problems with them. I used those heads for 6 years and have posted the info on here many times.