Valve guide boss, Porting GT40 irons

[fidstang]

I was wondering if what I heard is true. Can you grind the exhaust valve guide boss down to the roof of the port? Some one said by doing this it will improve the flow of the gases out the port exit. I already have one almost to the port roof. But, I didn't think to ask if it would cause any problems with the valve stem or guide. Did I **** up or what? Here are some pics of the one almost complete and one I haven't touched yet.

 

[Bladez5_0]

Try photobucket instead of the hard drive on you computer to link the photos too.

 

[poneypower89]

Try photobucket instead of the hard drive on you computer to link the photos too.

HAHAHAHAHA, sorry.. thats just funny to me.

Photobucket.. or just get a yahoo/geocities account and use the website filemanager to host ur images

 

[fidstang]

While I am working on getting the photo's loaded. Has anyone done this with the exhaust boss? Figured I would try the forum before I PM Thumper460.

 

[fidstang]

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[fidstang]

No one! Anyone, please!

 

[Bladez5_0]

I'm not 100% sure but I do think you can grind it to the roof. I recommend you ask thumper to be sure.

 

[fidstang]

I just talked to my dad's friend who does porting work on the side and said their should be no problem grinding it down to the wall. So tomorrow I will continue after I get out of work. If it isn't raining to much, Damn Michigan weather!

 

[stang8urimport]

There is no problem grinding the valve guide to a certain point... Taking too much guide away will effect the stability of the valve in the guide. I would smooth the guide even (tappered) with the boss.

 

[rd]

You should be able to grind the valve guide smooth into the top of the port. Most people don't seem to because it does shorten up guide some. I think the guide is long enough, and I suspect the boss is there to pilot the valve guide drilling tool during production.

I cut an old head apart over the weekend, right through an exhaust port, just to see what it looks like, and there should be plenty of metal left.

 

[tmoss]

Post up a pic for 'em rd.........