What exactly is meant by unshrouding the valves? I have ordered a set of TA Stg 1 valves for my '72 heads which I intend on relieving the port entry to the chamber and 3-angle valve job and port matching to my tunnel ram. Any help? Thanks Royden
On my web site, there are photo's showing a stage1 chamber unshrouded. Its under services/455/stage1 conversion. I tried to post a direct link, but it didn't work right.
Here's the link to Gregs site you need...... http://www.gesslerheadporting.com/m...6dd80023623d/b6272214d1bc772285256e1a0004e725!OpenDocument It's good info, thanks Greg!
My chambers look different to those shown. Mine are more open chamber style. I dont' think unshrouding is necessary in my case as there doesn't appear to be any metal to remove and the valves. Royden
Panic is correct, but if you do it your self ,get a book on the subject, do it before you have the new seats installed, use a head gasket as a guide so you dont go to far. practice on a junk head. just a little advice, unshrouding i think is the hardest part to do, just because you have to be so careful not to mess up the seat or go to far out and screw up your commpression seal.
Royden - Alot of guys prefer to use your freshly bored & honed block as a 'guide' for unshrouding the chamber around the valves. Take some machinist's die or even a black magic marker, and 'paint' around the chamber on the deck surface of the head. Put the head on the block and snug it down with a bolt. Take a scribing tool and 'lightly' scribe the head from the underside of the block. That will show you the exact bore sizing on the head, so you know where not to go past.
Hi Guys, Scott is definately right about that! A FelPro head gasket has a 4.440" bore and the TA "Orange Crush" gasket is 4.375"...both of which are much bigger than your overall bore size. Using a head gasket is not the best idea for sure..:error:..use the block's bore if at all possible.:TU: Good luck...
thats sounds like alot better way to do it, i wounder why i never heard that one before, even some of the books i have say to use the head gasket. i have only ported 2 sets of heads myself so i still have alot to learn.
The heads that I have are '74 model. The chambers are different as I said before. Anyone with these style heads that has done this before? And is it necessary to do it on these heads. The whole chamber is round and does not follow the valve profile like earlier stg1 heads. Thanks for your input guys! It is a big help considering that I live downunder and don't enven know of a reputable machine shop. I think it will take up most of my time liasing with the machine shop I decide to use, to make sure that what I have learnt on this forum and from books I have read, that it is done correctly. Royden
Does Bill (BuickStreet) have any suggestions for you? He's a 'little' closer than the rest of us!!:Brow: :grin: