Posted By: Suregrip
Replacement Valve Guide Sizes? - 10/31/18 10:56 PM
Small block 340 with X-heads. My machine shop is having a problem finding replacement valve guides in an over-size to press into the head. The heads had bronze guides and some of them were moving due to previous incorrect machine work. I am looking for a guide that I can have pressed into the heads in an over-size. Does this part exist? If so where to find it? Any other solutions? My machine shop is not Mopar-centric...
Posted By: calrobb2000
Re: Replacement Valve Guide Sizes? - 11/01/18 03:45 AM
hi
what size do you need ?
what size are the holes now ?
Posted By: chargerbr549
Re: Replacement Valve Guide Sizes? - 11/01/18 06:11 AM
I have run across where sometimes the bronze guides will actually shrink either from heat cycles or overheated or the quality of the bronze material isn't very good and they will start to slip or move around, not necessarily because of improper machining.
Like what was said before what size is the guide bore? Generally the guide bore is .500 id and the guide od is .502 and if the guide bore is bigger you should be able to find guides that are bigger in od and the guides might have to be polished down to get the proper press fit.
A very good quality bronze guide to use would be C.H.E they can make exactly what you need or you can usually find a guide thats close and make it fit your application. Here is the link for them below.
.https://www.cheprecision.com/html/guides.html
Posted By: gzig5
Re: Replacement Valve Guide Sizes? - 11/01/18 04:05 PM
It's essentially a brass/bronze tube right? They should be able to chuck them up on an arbor in a lathe and knurl the outside for part of the length. This will increase the effective diameter and should allow them to be pressed in and hold without any adhesive. May have to play with the depth on one or two to get it right. Might save the cost of custom parts and shouldn't be expensive to do. Should probably be honed internally to correct size because the knurling operation will probably close the hole up a little.
Posted By: Suregrip
Re: Replacement Valve Guide Sizes? - 11/01/18 04:24 PM
I am looking for an valve guide in 0.372 inside diameter to machine for a 0.375 valve stem, the outside diameter needs to be slightly over the stock .500 size. Machine shop says .503 to .505?
Posted By: Mopar Sam
Re: Replacement Valve Guide Sizes? - 11/01/18 09:03 PM
A couple of years ago I needed some .507 od guides and found them through PEP Precision Engine Parts. Go to their site, click on " downloads " then download the PEP catalog by size. They list .372 id x .504 and .507 od guides.
Posted By: dogdays
Re: Replacement Valve Guide Sizes? - 11/05/18 09:08 PM
It sounds like the guides are already out. Too bad, otherwise the shop could have left the guides in there and installed sleeves.
Check out Goodson.
R.
Posted By: madscientist
Re: Replacement Valve Guide Sizes? - 11/05/18 09:34 PM
I've seen .530 OD guides. But you also need the reamer.
I can say in almost 35 years I've never seen your issue.
Posted By: Barry70GTX
Re: Replacement Valve Guide Sizes? - 11/06/18 02:21 PM
A couple of years ago I needed some .507 od guides and found them through PEP Precision Engine Parts. Go to their site, click on " downloads " then download the PEP catalog by size. They list .372 id x .504 and .507 od guides.
I'm pretty sure PEP can make whatever you need.
Posted By: Twostick
Re: Replacement Valve Guide Sizes? - 11/06/18 05:22 PM
You need a new machine shop.
Kevin