a couple of porting questions

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Old May 3rd, 2015, 11:09 AM
  #1  
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a couple of porting questions

I started porting my B heads. I have been studying the priceless home porting thread and also the recent porting thread on ROP.
Since this is my first porting experience ever, I am concentrating on getting the ports and bowls smooth and not so much on re-shaping and customizing the shape of these.
I have a couple questions though, since I dont want to hit water and such :-)

I am not sure if I can take this bump out... the heads is upside down, so it is on the roof and I am pretty sure it is an exhaust port. I guess this is an EGR bump? Can I smoothen it out completely, or will I hit water if I shoot for flattening it out ?
32279FD9-861A-49ED-B3C9-5A962D126B89_zpsms9vcxsj.jpg

I have only used the carbide grinder so far. I have some 80 grit rolls that I will finish the bowls / ports up with. How far can I go with teardropping the guide? I know the wall right above the guide has water on the other side ? The surface in the bowl has been smoothed out, so any bumbs and unevenness is gone.
DCE5E21D-8A61-423F-99B2-14416CE6CA05_zpsf83r4mzc.jpg

I will do all ports on both heads the same way for starters, so they are the all the same and then I might go into re-shaping the ports. 67 cutlass freak told me to square the port right before the shortside radius.
Btw I measured the port volumes to be 178 intake and 130 exhaust.
The heads will get Milodon 2.07 intake and 1.71 exhaust valves and a 3-angle valve job. These valve sizes should fit in there, right ?
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Old May 3rd, 2015, 01:20 PM
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Jacob,
Get rid of those bumps entirely. Some people refer to those as EGR bumps, but actually they are bumps that were made from the A.I.R. casting boss. Some California heads had AIR tubes bac in the day. Be careful when your grinding not to dip down into the port too much on the sides of the bumps. It's easy to do. Here's what it should look like when you're done -
123-2331_IMG_zps8ndymd9o.jpg
You can go a little further with the tear dropping on the guides -
123-2328_IMG_zps4tlibk2u.jpg
You should also pull the bowl back a little more on the intake for sure -
123-2309_IMG_zpsdejqfj15.jpg
Start roughing in your valve job and use the 75 degree stone to help show you how far to full the bowl back. You should have posted these photos and questions in the porting thread. It's great to see you are making progress. Did the guy come through with the SB heads for you, and if so, how do they look?
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Old May 3rd, 2015, 03:27 PM
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Hi Dave. I thought it was better to keep your thread free of "other people's attempts" :-) I copy&pasted my entire post into your thread.
The ports have bumbs right under the bosses for A.I.R. pipes, if the heads hadhad that feature, that bumb I made flush with the rest of th port roof. This is another bumb, I guess it must be in the intake port then... ?
I am still waiting to hear from Kurt about those 5's. Paypal took the money out of my acount last tuesday. I am sensing a dispute case coming up :-/ Good thing I marked the heads as goods instead of gifts, like you suggested.

I will stick the 75 degree stone in there for giudance then.
Let's carry on over in the proper thread.
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