19cutlass71supreme

I've asked this question befor but I figured I would get better answers if I made it separate thread for it. I'm using stock 350 heads. Been ported and gasket matched. No other work was done to it. What size valves should I use and what other kind of work( if necessary ) should I have done to my heads. Thanks

oldcutlass

It really depends on your cam.

coppercutlass

I think Your machine shop should be able to set you up. No offense but if they are already working on your heads aren't they planning on doing a valve job ? Usually its all done at the same time usually the shop will ask what your plans are what you want to run. Usually big intake and ex. valves better springs and all new hardware are the way to . Atleast that's what I had done to my #6 heads just a little bowl work.

19cutlass71supreme

Unfortunately the machine shop did not ask me my plans for this engine. I actually took it to an engine builder who has good connections with a machine shop. Saved about $400 going this way. Anyways, I dropped it off with the valves and springs still in it because I didn't have the tool or remove it so I'm guessing they are gonna do a valve job on that set up. I'll try to see if they can pause the process on the heads so I can do some more research on parts.

Coppercutlass, I know you helped me on this topic befor. I still have the message you sent me with the size of valves your using. When I started digging, I found out I would needs a good amount of work done to run those, work that I didn't ask for on those heads. I only asked to have them ported and polished a little. I'm going to go with roller rockers now so I'm going to have to add work to them so I might as well just go ahead and have them set up for bigger valves

My main focus on this thread was to find out what's the biggest size valves I can use if I kept it stock or if the work is something I can do at home fairly easy considering I never did it befor.

coppercutlass

To run the prw roller tips you have to at the most re tap the holes for bigger thread studs if you are not running the stock size thread. So you are going full roller rocker ?

67 Cutlass Freak

First of all you have posted this in the Racing High Performance section. You have me confused as to whether you're doing a stock build or a performance build. You also stated that the porting was done and some runner matching as well. Then you just stated that the machine shop is doing the port work now, so I'm a little confused. The overall performance goals and entire engine package should dictate the size of valves you will need. The valve will only flow as much as the port will allow. You said you assumed a valve job would be included in the price of your machine work. Don't assume anything. Have the machine shop give you an itemized list of what services they will be performing and how much they will be charging. Get it in writing. Post it up here. If your machine shop is not very experienced with Oldsmobiles, find another. I don't care how cheap the service is, you don't want to blow it up and do it a second time. You should check out this thread about Home Porting Techniques, read it from beginning to end. This should help you to know what you're dealing with-
https://classicoldsmobile.com/forums...echniques.html