Ive been searching the boards for the past few days trying to find something similar to this but I havent...

Im rebuilding a 350 and Im just about to start reassembling my LB9 heads. (which I know are 305 heads... Im going for increased compression) These heads have had a 3 angle valve job and have been ported for maximum breathing and once they are equiped with my new springs and seals; they will be completely ready for my engine... except one thing...

The cam shaft has a .495 max lift and everything I have found says that 081 heads go to a max of .480 lift.

Now, these heads have hardened seats in them and they are still in perfect condition and I would hate to take them back to the machine shop to have them grinded out and etc.

Ive heard of some people using chrysler 2.2 valve seals to increase clearance for lift but Im not sure how much clearance it gives me...

I would like to know if there are any ways around taking these back to the machine shop. I would hate to pay tons of money for new seats that arent necessary. I want to make sure the heads can take .495 lift and if at all possible maybe even get them up to .530; however, right now the .495 is most important.

All help is greatly appreciated.

Thanks

 

305 heads = overheating, spark knock, and poor flow. Cheap vortecs are a good budget build for heads, or there is always the older heads and the aftermarket. I know around here I can get vortecs off a running engine for $80..... Just my opinion.

 

i have heard that chrysler 2.2 thing too but im not sure how true it is. why not call the shop that did you work on them and ask?
but you will also ahve a problem with the studs pulling out - you need to either pin them or have them drilled and taped for screw in studs. no matter what i use i will have to get them machiend for screw in studs and the most expensive shop around only charges 80.. - provided i break the heads down for them.
if you are going to do that you might as well call and ask them how much to shave the valve guides down too - because eventually you are going to want to put in 1.6 rockers and they need the room.
do it all at once and you dont have to pay to do it twice.
might as well port and polish them too.

 

I run the 081's, and though I did have detonation issues initially
and I can assure you I don't anymore, and the car moves its own
weight far better than it ever did before.

Needless to say, Id like some vortecs.

 

Ive heard and seen plenty of builds using 305 heads and as long as you can address the ping right after the build then youre fine. The heads have been port matched and have had a valve job they breath more then enough for the TPI intake that Im putting on it... Thank you for your opinion but the LB9 heads are staying

The chrysler 2.2 seals will work... no shaving needed =D and the heads are already port matched and have had a valve job =D