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Double Cut Egg Shaped Carbide Burr, a ball shaped burr, and a Christmas tree shaped burr (least useful). Mostly just the egg shaped one. I have a complete set coming from Amazon but they are lost in the mail so I just started with these. Trying to form a decent port so I can eyeball copy it to all the other ports. I'm using a Milwaukee M12 Straight Die Grinder I just bought... in love with it.
I just want to point out once more, I do appreciate any constructive criticism or even more so, direction on how to proceed would be great; but keep in mind these are going on a beat up bone stock LS1 with a loose 3200 converter and a TSP Torquer V4. I can click the order button on a set of nice heads but this is designed to be a learning experience as I am looking to expand my knowledge and skills. First time using a die grinder, first time porting anything. Trying to visually make reasonable guesses in my head on how I think the air should flow through the port without any actual experience in this area. If these heads come out ok, I may have couple of ports flowed just to see how good or bad they are but so long as I don't open up any water jackets I am going to run them even if they are worse.
Not at all to knock what you've done so far, you're getting good practice!
My thoughts are to concentrate more on bowl work and a pristine multiangle valve job, plus just knocking off any zits and warts in the ports themselves, rather than port the whole passage.
I've often heard that 80% of a good port job is in the bowl work and valve job.
You don't want to slow the flow.
Those polishing buffers, rather than grinders or sanders, do well on that sort of thing; they round over the steps and edges without removing much metal. Having a small recess there doesn't matter so much as long as there's no sharp edges to glow red-hot or cause turbulence or any of that.
That seat looks like it got its money's worth out of it.
If you want to get a visual of flow, shoot a garden hose through it. The difference between an as-cast stock head and a ported one can be pretty amazing.
Take them to a local machine shop and have them plunge cut 88/89ish % of your valve. Don't try to do this by hand.
not saying it can't be done. But if you really want to do a nice job. You can have machine shop do this or newen makes a flat cutter that you can adjust and do this, works well. Gets a straight hole.
I use this sometimes on rd stuff that i don't have a cutter for. Works surprisingly well. Cuts right thru seat.
Not at all to knock what you've done so far, you're getting good practice!
My thoughts are to concentrate more on bowl work and a pristine multiangle valve job, plus just knocking off any zits and warts in the ports themselves, rather than port the whole passage.
I've often heard that 80% of a good port job is in the bowl work and valve job.
You don't want to slow the flow.
I didn't open the ports up all that much, I kind of just brushed over them with the grinder and then hit them with 80 grit rolls. I've read so many different threads, watched a month's worth of videos... to be honest I've actually confused myself and over complicated this. The wall that houses the rocker stud; some people remove it and some people do not. Some people remove the swirl ramp and others say not to remove it because it hurts part throttle response. Here is my very basic thought process: While slowing down velocity could lead to the car feeling sluggish at part throttle, I want to believe opening up the port, removing the swirl ramp and increasing the size of the bowl slightly will lead to bigger wot power. The cam I selected (more like selected me as I got it cheap) has a power band that ends right around 7000 rpm. Its also pretty big in my opinion although I know for most of you its a baby cam. My hope is power will feel stock driving locally and my gains will be up top. This might be completely wrong, but like I said, I've read so much contradicting information I wasn't quite sure how to proceed. Now that I have my general design, I can try and duplicate it in the rest of the head.
Hopefully I am not "hurting" flow to a point where the engine is going to be unresponsive. That is a fear of mine, as I will agree with what you said in regard to just basically cleaning it up. I have a very good, race winning machine shop locally. The last time I had them port a set of heads was about 10 years ago for my corvette (pictured in avatar). All they did was a very light removal of the swirl ramp and a 3 angle valve job and the car picked up a tremendous amount of power. I recently tuned a truck they built, same formula, same result... so its likely nothing I am doing is really going to be any more beneficial over what they do.
Originally Posted by RB04Av
That's not the floor, it's the roof.
Those polishing buffers, rather than grinders or sanders, do well on that sort of thing; they round over the steps and edges without removing much metal. Having a small recess there doesn't matter so much as long as there's no sharp edges to glow red-hot or cause turbulence or any of that.
That seat looks like it got its money's worth out of it.
If you want to get a visual of flow, shoot a garden hose through it. The difference between an as-cast stock head and a ported one can be pretty amazing.
Yes, lol, I meant to say that. I'm opening the roof slightly in the exhaust ports and just polishing the floor.
I have to figure out how to get in there and carefully smooth that area without messing up the seat. The seats need to be redone. I was hoping not to but these heads in general are shot. I scrubbed them out, put them in the dishwasher, and now I am literally grinding the carbon off. I am going to polish the valves... they have caked on carbon and were somewhat stuck in the guides because of some sort of gunk that was in them.
Originally Posted by Lsbmer
Take them to a local machine shop and have them plunge cut 88/89ish % of your valve. Don't try to do this by hand.
not saying it can't be done. But if you really want to do a nice job. You can have machine shop do this or newen makes a flat cutter that you can adjust and do this, works well. Gets a straight hole.
I use this sometimes on rd stuff that i don't have a cutter for. Works surprisingly well. Cuts right thru seat.
I'm not familiar with the term "plunge cut," but I will look it up. Its become apparent that these heads do need a valve job. I am considering buying some tools and attempting it myself. That is a conversation we will have after I complete the porting and if the heads come out good enough that it is worth moving forward with any of this. If so we will take the next step. The good news is I am friendly with the guys at the machine shop and although they will laugh at my work, ultimately they will correct if for me if I've made any mistakes which is nice. I know they will appreciate the effort I put in even though they are trying to run a business.
Your going to need a vj. Use the angles I said earlier. .
Don't use 30/45/60. which what most local shops will have
as most oem is this. Dont believe them if they say different Just roughing it up and smoothing spots isn't going to help your going to need grind in the right spots, a vj and the correct seat %. probably end up 220cc or better.
Your going to need a vj. Use the angles I said earlier. .
Don't use 30/45/60. which what most local shops will have
as most oem is this. Dont believe them if they say different Just roughing it up and smoothing spots isn't going to help your going to need grind in the right spots, a vj and the correct seat %. probably end up 220cc or better.
hmm... pretty sure that's the 3 angle they do. I'm going to do some more grinding tomorrow. Trying to get both heads done by the end of next week. I'm really taking my time, not rushing. There's just no reason to. Its been snowing for days. Just got another 3-4 inches today. The car isn't coming into the garage for the swap anytime soon. I also want to polish the chambers a bit. These heads need resurfacing as well. I have a few more decisions to make. This can be over and done with with the porting and a valve job, and a base resurface... or this can head in the direction of milling the heads down, raising the compression and fly cutting the pistons. I haven't decided how far I want to go yet. The car I am putting this into isn't worth the work I have done so far lol.
Back 20 years ago when I was in school, I was required to do a valve job for course completion. The instructor brought out a box of stones and pilots. 3/4 of the box was missing stuff. I still remember looked like something from the 50s. Anyway, I did a valve job on one head, on a 305 Monte Carlo. A lot has changed since then, and this LS stuff is a little more precise, but I found this kit online and would love to own something like this. Its made by Neway. Not sure if its really "professional automotive grade" but for a guy like myself doing a set of heads once ever 5 or so years it might be nice to have. I would leave this to a professional if I was building something serious but on this car I really would like to give it a try. Lets see how I make out this week, this project may be dead not before long if I make a mistake.
Your exhaust looks good. Clean up the intake and open the throat to 88% or 89% of the size of the intake valve and 86% on the exhaust. I have the throat open to 88% on the 243s on my '01 and the car likes it.
Use stones if you don't have access to seat n guide machine. I always finish with stones. Neway ok for plunge cutting seat with there flat one. I wouldn't cut seat angles with neway. Only thing that's really changed since a long time ago is angles.
Ford head I did. Bowl hog or plunge , just say i cut straight down with cutter and you can see where I stopped. Supposedly water is close if I went deeper. I broke thru on one these years ago.
This wipes the short turn out. So that needs to be ground back in. And bowl ported more, And new vj.
Ford head I did. Bowl hog or plunge , just say i cut straight down with cutter and you can see where I stopped. Supposedly water is close if I went deeper. I broke thru on one these years ago.
This wipes the short turn out. So that needs to be ground back in. And bowl ported more, And new vj.
That's beautiful work! I'm trying to get back into "Hot Rodding," a totally lost art. The last couple of cars I have owned have been expensive (by my budget), quite frankly probably cars I don't have any place owning. So like everyone else on here regardless of how nice they are I am never happy and always want to mod. The last few years I have gotten caught up in the "what's the best......" threads. I wanted heads for my C6 so I had the 243s professionally ported. I ordered all new parts, top of the line lifters, had the valves changed for titanium ones, IW balancer, you get the idea. I really enjoy the build process, I want to get back to more of the DIY stuff, even if the results can't (nor shouldn't) compare to CnC Ported heads, and lightweight valvetrain and so on. That way I can still have something unique I put together and call my own. Check out my Chevelle Threads to get an idea of the type of stuff I enjoy doing.
This will not be the last set of heads I do. This is a good practice run. I need to run these if I don't destroy them but I will probably port the 241s when they come off and throw them on the shelf. It would be nice to have work like yours someday.
Almost done with the first head. All the ports are ported, intake finished with 80 grit and exhaust with 120.
Need to start thinking about what I want to do with the valve job.
Also need to figure out what the safest way to polish the chambers are. I want to remove as little material as possible to keep compression up and just work on polishing out and flattening the casting.
Things were going way too smoothly, I even decided that I was going to pay my machine shop to do a nice valve job. While looking over the second head I noticed cracks in between the valves. Immediately ran over to the completed head only to find less pronounced cracks in 3 of the 4 cylinders. I am very disappointed to say the least, is this correctable or am I looking for a new set?
Is there a reason why the combustion chambers are so rough? In the pic above, you can clearly see that the chambers have a rough texture. They look like sandpaper.
I also have a set of 706 heads that I would like to home port. I still need to get the tools, but I was wondering if the chambers needed to be smooth.
Is there a reason why the combustion chambers are so rough? In the pic above, you can clearly see that the chambers have a rough texture. They look like sandpaper.
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02-22-2021, 04:14 PM
