Head Porting Advice

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GermzD74

GermzD74

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Hello guys, need a few tips on porting my EQ magnum heads.

I've all ready started shaping the valve guides round. Looking at the following picture...I'm not sure how to shape the marked area into a smooth sharp edge. I tried using the long shank carbide bit that I used to shape the guides but they tend to bounce around too much. For those that have done this, what tools can I use to accomplish this?

I looked for grinding stones, but couldn't find any long shank ones (6").

I want to be able to shape the marked area tapered with a close to sharp edge at the top so that it flows with the least restriction and to smooth out the roughness the carbide bit left.

The second picture is of a head I found online, looks similar to mine, I want it to come out similar to that.

Thanks
 

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I find a higher speed with carbide works better for me. Don't try to cut too much at a time just touch the casting lightly. Also wear a thin leather glove on your opposite hand and use your index finger to steady the carbide shaft near the valve seat. I have never used stones at all. After you make your cuts with the burrs use various shaped sandpaper rolls to smooth down the roughness. Most porters will tell you to leave the surfaces somewhat rough to aid in dispersing the fuel droplets. As always my advice is worth what you paid for it. Dan
 
Carbide cutters work great in getting the basic shape then I used the porting kit (sanding rolls. They last much longer than grinding stones) that Summit sells for smoothing things down after I get the basic shape ground in. I also run the air at 60-65 psi to slow down the die grinder so not to take too much out with the carbide cutters then. 90 psi is ok with the sanding rolls. Yours are looking ok so far. Open up the area beneath the valve seat area too. Got quite a big lip there giving a funnel effect. I did my EQ's and found quite a bit in working the intakes even in spite of the huge pinch they have right at the port entry but the exhaust didn't improve a lot even though I took mine down to look very similar to 2nd pic you have there.

Oh yeah, use the shortest carbide cutter you can as the longer they get the harder they are to keep stable. It takes a long cutter to reach in through the port window but doing a bowl doesn't. That's been my experience with them.
 
You guys are awesome! Who needs an experienced father when I can have three wise FABO fathers lol. I still love my father, although he never understood my hobby; just recently he's starting to see that I won't struggle so bad with these "old junk" as he puts it because he sees how I get most of my stuff fixed myself.

Anyhow, I'll update you guys on how my whole 340 build is going, short block is built and I'll make a separate thread on it with pictures.

Thanks again!
 
Hey fishy, did you open up your exhaust ports matched to your gasket or left them alone? A friend is telling me to leave them alone for now...and when I really start racing that itll be helpfull but for the street...the restriction will give me more lower end torque...Im using dougs headers.





fishy68 said:
Carbide cutters work great in getting the basic shape then I used the porting kit (sanding rolls. They last much longer than grinding stones) that Summit sells for smoothing things down after I get the basic shape ground in. I also run the air at 60-65 psi to slow down the die grinder so not to take too much out with the carbide cutters then. 90 psi is ok with the sanding rolls. Yours are looking ok so far. Open up the area beneath the valve seat area too. Got quite a big lip there giving a funnel effect. I did my EQ's and found quite a bit in working the intakes even in spite of the huge pinch they have right at the port entry but the exhaust didn't improve a lot even though I took mine down to look very similar to 2nd pic you have there.

Oh yeah, use the shortest carbide cutter you can as the longer they get the harder they are to keep stable. It takes a long cutter to reach in through the port window but doing a bowl doesn't. That's been my experience with them.
Click to expand...
 
I wouldn't really mess with the exhaust much at all. They flow very well.

Maybe take a sanding roll and clean up any casting flash, etc. I wouldn't open or reshape them.
 
Don't worry about that part of the guide boss. Don't reduce it any from where it's at.
 
I wouldn't take anymore out than what you have...use a cartidge roll 60 grit to clean up what you have done. A ball shaped carbid cutter 1/4" and 3/8" diameter head will get the shape you are seeking. Also they are much easier to shape the short side turn than a regular oval (E5) cutter. Always use carbide cutters for removal and cartridge rolls for finish work. Nothing finer than 60 grit for intake , you can go up to 120 for exhaust side. As has been stated..turn carbide cutters fast..25000 rpm the faster you turn the cutter the smoother the cut. Turn cartridge rolls MUCH slower or they will come apart. I use an electric die grinder for cutting. Makita GE600. About $100. bucks turns 25000 and runs VERY cool for HOURS. Pnumatic die grinders will get VERY hot in your hands quickly and also run your compressor to death. As the air supply runs down the tool slows way down , a razor sharp carbide at 12000 will cut and perform like a very dull carbide at 25000. Dip the cutter in a container of motor oil every 60 seconds or so and the cutter will run MUCH cooler and last MUCH longer. EYE protection ALWAYS, a resperator will allow you to live longer too. Iron dust is mean... LOL.

Terry
 
GermzD74 said:
Hey fishy, did you open up your exhaust ports matched to your gasket or left them alone? A friend is telling me to leave them alone for now...and when I really start racing that itll be helpfull but for the street...the restriction will give me more lower end torque...Im using dougs headers.
Click to expand...

I did but only a very slight amount. The gasket size was real close as it was. Just did enough to blend them to the gaskets and headers. I took out any flashing and polished them then re-flowed them. Actually lost 3-4 cfm below .300 lift and only gained 10 cfm at .550 and 16 at .600 lift. IMO it wasn't worth the time and effort especially since my engine build is very mild. As CB said they flow really well when stock.
 
D-mailman said:
I wouldn't take anymore out than what you have...use a cartidge roll 60 grit to clean up what you have done. A ball shaped carbid cutter 1/4" and 3/8" diameter head will get the shape you are seeking. Also they are much easier to shape the short side turn than a regular oval (E5) cutter. Always use carbide cutters for removal and cartridge rolls for finish work. Nothing finer than 60 grit for intake , you can go up to 120 for exhaust side. As has been stated..turn carbide cutters fast..25000 rpm the faster you turn the cutter the smoother the cut. Turn cartridge rolls MUCH slower or they will come apart. I use an electric die grinder for cutting. Makita GE600. About $100. bucks turns 25000 and runs VERY cool for HOURS. Pnumatic die grinders will get VERY hot in your hands quickly and also run your compressor to death. As the air supply runs down the tool slows way down , a razor sharp carbide at 12000 will cut and perform like a very dull carbide at 25000. Dip the cutter in a container of motor oil every 60 seconds or so and the cutter will run MUCH cooler and last MUCH longer. EYE protection ALWAYS, a resperator will allow you to live longer too. Iron dust is mean... LOL.

Terry
Click to expand...

I read this a few hours too late, I ended up shaping them a bit sharper...hopefully it'll result in better air flow. The problem I was having is I was using too think of a carbide cutter. Replaced it with an egg shaped cutter and left a much better result giving me better shaping angles. I've yet to finish it up with the sanding rolls. I used double leather gloves to steady the shank but could still feet the heat...was manageable though. Thanks for all the advice.
 
fishy68 said:
I did but only a very slight amount. The gasket size was real close as it was. Just did enough to blend them to the gaskets and headers. I took out any flashing and polished them then re-flowed them. Actually lost 3-4 cfm below .300 lift and only gained 10 cfm at .550 and 16 at .600 lift. IMO it wasn't worth the time and effort especially since my engine build is very mild. As CB said they flow really well when stock.
Click to expand...

For the exhaust, I'm going to use Mr. Gasket Part # 5935, the port on my dougs measure 1.25 X 1.75...this gasket measures 1.30 X 1.80...hopefully it'll seal okay.
 
Here's some pictures on the finished result, I took quite a bit off from the top to shape it sharp...hopefully it'll hold the push force from the valves haha.

Need to go over it lightly with the sanding roll cartridges.
 

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fishy68 said:
I did but only a very slight amount. The gasket size was real close as it was. Just did enough to blend them to the gaskets and headers. I took out any flashing and polished them then re-flowed them. Actually lost 3-4 cfm below .300 lift and only gained 10 cfm at .550 and 16 at .600 lift. IMO it wasn't worth the time and effort especially since my engine build is very mild. As CB said they flow really well when stock.
Click to expand...

Hey Fishy, how about the intake ports? I need some more advice before I call it finished and start assembling the heads. Here are some pictures, should I make the curved walls as straight as I can? My friend told me that I could take as much needed to make the curved walls straight as long as I don't go through it. My concern here is, where are these heads prone to cracks? Don't want to weaken them. He said the port runner walls don't get that hot and shouldn't worry about cracks there.
 

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First of all--great job on the bowls, it looks like you have removed alot of iron and that really picks up the flow. Second of all get them on a flow bench! All of your great bowl work will more than likely overload the short side and you will have turbulence that will set in at (WAG) .530" valve lift, this will require going back and forth between the pushrod pinch and the S.S.. With that being said don't worry too much the EQ Mag's are hard to mess up, they always seem to work great. I have written a CNC bowl porting program that nets a flow rate of 270cfm with no other work other than valve job. I also wrote a CNC intake gasket program that gets a true 1.000" through the pushrod pinch. The result? After blending all of the material where the CNC stuff leaves off--277cfm --huh? Well then the S.S. became critical, so after that is worked properly I saw 291-300 cfm between all 8 ports @ .650" I figured that was good enough for what the goal was. J.Rob
 
GermzD74 said:
Hey Fishy, how about the intake ports? I need some more advice before I call it finished and start assembling the heads. Here are some pictures, should I make the curved walls as straight as I can? My friend told me that I could take as much needed to make the curved walls straight as long as I don't go through it. My concern here is, where are these heads prone to cracks? Don't want to weaken them. He said the port runner walls don't get that hot and shouldn't worry about cracks there.
Click to expand...

I didn't take any more out of mine that what yours look like now because I didn't have an accurate tool to measure how much material was there and didn't want to break through. The pushrod pinch is quite profound on Iron Rams but from everything I've read it doesn't make a huge diff. in flow if you take out the most you can. Mine peaked at 270 with port openings and bowls that look like yours. It seemed like I didn't gain a lot for all the time I put in because OOTB they flowed 250. But... the flow increase started with +8 cfm at .200 lift and increased exponentially from there and the low lift numbers are what are most beneficial.
 
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