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Old 11-06-2012, 11:45 AM
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hcompton hcompton is offline
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Quote:
Originally Posted by ssmonty View Post
Hcompton,
"Yes they cnc the heads but do not cnc port the heads its just part of the manufactuing process. Cnc porting cost extra." No BS? They don't CNC port the head for free? Wow, I never would have though they would charge extra for time spent on a $250,000 5-axis machine. By the way, I never said anything about CNC porting.
"Also if you need more flow just buy a head that is desgined to flow more."
Just give him the money.
The op said he had a set of heads allready and that he was concerned that they may not be enough for a 383. I was trying the show him that they could be improved somewhat with a little work. I wasn't trying to tell him to do all I did, just some of many options he had to make them better.
"The reason not to port aftermarket heads is they do produce the numbers unmolisted. If you have an issue with the head you cant send it back if its cut. Get 210cc heads or 234cc heads."
Am I the only one that has tried to clean-up an aftermarket head? Do you think they'll take back the op's used heads if he does'nt grind on them? Maybe the op doesn't want to lose low end throtle response and torque by giong to a larger port head. He only said he wanted it "kinda hotish". I think he would be happy with a 383 with the Edel. heads he has, and I think he a would like them even more with a little work done.
Funny, your the one I see telling others to follow write-ups in Hot Rod magazine for engine builds. Don't I see Hot Rod doing articles on DIY porting now and then too?
Like I said, most wouldn't reccomend a dremel and I didn't have an air compressor. I also thought I could do what I wanted with a $30 rotary set I saw at Advance Auto vrs buying a $150 Milwaulkee grinder and $50 worth of bits for a one time job. You don't think an electric grinder can remove material very fast???? I still think a dremel style tool with a wand, and keeping it moving back and forth without letting it stay still for any length of time, with a sanding roll/cartridge just below the seat insert, and around the chamber, and the short side radius would do a decent job of bowl clean-up/ chamber polishing for the DIYer.
ssmonty
Not trying to argue with ya. But you dont move the bit back and forth when porting. You cut for right to left against the rotation of the bit. Sanding rolls are for cast iron heads, use a home made flapper for aluminum heads. Ask at local machine shop they can show you how it works. Home made flapper is 1/4 inch tool steel rod with slit cut in top for sand paper. just one 3 inch x 1 inch strip folded over to fit inside the bit. It will cut fast and clean with no bumps and leave your port floors dead flat. Sanding rolls will leave bumps and dips in the port floor. use cross cut carbides for any metal reshaping.

Electric die grinders are more powerful than air. They have better tq that gives better control. Not just whacking it back and forth a bunch of times.

The OP has heads that are fine for 383 no need to take a first run at porting with an expensive set of heads. They will make big power without anything being done to them. Why take the risk of bad port work on 1500 heads when they will do the job bone stock. So kinda hotish = stock edlebrock heads. Right?
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