Bronze Valve Guide liners
 

HM,, well while checking out the springs and such on a set of heads I just got, I realized the guides were just knurled and dont have bronze liners. One head is already on the engine. Should I have the bronze guide liners put in? Is the head gasket on the head I torqued down now junk if I remove the head to get this done?

If the guides are good I'd run them and replace for bronze after they wear. I'd also mill guides for teflon seals at that time.

You cannot reuse head gaskets.

Thanks, Thats what I figured. They have teflon seals already but the exhausts werent machined down far enough for my .553 lift clearance. It looks like the retainers will hit the teflon. I may just do it now and be done with it. I will have plenty to do to the second engine next winter.

This is just my two cents, but if it were me I'd take the heads down for bronze guides now. I don't care for knurled guides for a couple reasons- knurling reduces the contact area of the stem against the guide which accelerates guide/stem wear, and bronze is a self-lubricating metal while cast iron is not. But like I said, that's my two cents.

Thanks, Thats what Im gonna do. I will be very busy with the other engine next year and I dont want to have to mess wth this one. Plus, the seal clearance bothers me too. Oh crap, the valves have to be reground after the liners are installed?? I didnt know that? Is that right?

My 2 cents after tearing down and inspecting guide wear on alot of motors I will never run or recomend knurled guides or the thread in guide inserts.

Formula31
Is this the set of 049 heads that you just bought?

yup

Tom,
I have the other set of those heads. I was told they were Comp Cam springs and hardware set up for an Ultradyne Flat Tappet Cam .550 intake, .558 exhaust lift. We are going to run on the Dyno in about a week, maybe I should take a little better look.

My springs checked out at 130 lbs at 1.85 which is Ok, just need to be careful breaking them in. I didnt like the shims they had under the intake valve on one head and put hardened ones in there. The other head had good shims. But the clearance between the teflon seal and the top of the valve spring retainer on the exhaust valves was only around .53. The intakes had tons of room. I think when they cut the guides for the seals they forgot that the exhausts get a huge shim to take the place of the rotator. I have to get home to check the other head. I just assumed they would have bronze guide liners in them. Oh well, its only money.

F-31, the valves don't need to be reground, only the seats. I'm assuming you meant you had .053 retainer-to-seal clearance, not the .530 you had in the previous post. The springs I like to use for cams like this check out a little lighter than yours; 115 lbs closed when new and they settle in at 105 lbs after a couple hours running. But you're right, those springs will be fine. Be sure to use a good high-pressure cam lube on assembly.

New guides being put in now. CR, the seal to retainer distance (valve closed) was .530 which of course is very bad with a .553 lift cam. Im having that cut down .125 which will give me plenty of clearance even if I go to a bigger cam later. It's wierd, just one head, just the exhaust valves were off. Oh well, normal HP recipe, just add more money. Im also gonna set the spring height to give me 115 closed. I have the room. And it should give me about 290 full open.

Again, this is just my opinion. But I still think the 290# is a touch on the stiff side. But if these are new springs they'll probably settle in at around 275, which is where I like to have the open pressure. Glad to hear you're just about ready to assemble. Remember, good cam lube.

My thoughts exactly, Ive got so much red cam lube everywhere I am goin to have to change oil 5 times in the first 20 minutes. :D :D I just wish I didnt have to put another $250 into them for guides. O well.