Fbody1

what reasons would cause valve guides to fall out? the only thing holding them in was the valve.

1racerdude

Ya retainer's were hittin the guide from to much lift without the right retainer's or ya needed to cut down the guide's to clear. Ya were close to coil bind?

MachinistOne

Had they been replaced before? Bronze? cast?

Fbody1

no they had not been replaced before,i couldnt be close to coil bind springs will handle 600 inch lift,i only have a hotcam(.525 lift). right now i am having problems finding oversized bronze valve guides need 0.561 cant find these anywere any suggestions?

MachinistOne

Where are you pulling that .561" number from?
Have you measured the hole?
Is there pulled material in the bore?
Are they concentric?

Original bore size is .545" or .554" I believe. I can get the guides in oversizes....so answer those q's and I'll help you out.

Fbody1

the stock size is 0.557 my machine shop said he wants to go 4 thousandths over (0.561). a few of them pushed out with my finger and no i havent measured the hole but i can find out tommorow the actual size from the shop.i dont know if there is pulled material ill have to ask machine shop.if you can get me the guides in that size(bronze with collar) please let me know i need them asap i cant find them anywere. thanks!

MachinistOne

From what I can read into this, the holes are messed up and he knows this, therefore he is going to ream them to the next possible oversize which is 9/16 (.562) Now you need a guide which has .0015-.002" press fit--> ~.564" And instead of the stock style guide, you want one that is hatted as we call it.

I use a supplier called SI Valves for all my bronze guides, they literally have hundreds of different styles...

Bronze GM Aluminum Head FI : VG19290/00 (non-hatted though)
I can't access the generic hatted guides from my home computer, but I can lookup the part number for a good replacement for you tomorrow. Contact your machinist and make sure that is his plan, (9/16 final bore size after reaming)

Give him this info: SI Valves 800-564-8258 he can get a catalog and never have guide worries again.

1racerdude

He will probably need the flanged one's to keep it from happening again,don't ya think?

MachinistOne

If the press is setup correctly, and the bore is true, he will have no problems. I install full bronze guides in heads everyday and sometimes I use hatted guides, sometimes I just throw a .502" false in which has no hat. I have never had a guide drop.

Another thing I thought of today when I was looking up flanged guides for you is that the stock spring locator and those used for beehives will not fit over a hatted guide. So let me know if your machinist is going to ream that hole out, then the best idea is to call SI and tell them the hole size and get an oversize of the part number above with .002" press-fit.