Ported 416 heads
#151
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Re: Ported 416 heads
TxTtopZ here you go a day late but here none the less
It's big valve RHS Vortec vs BRODIX IK 180's.
This was 11cr, 1.6rr, 900cfm TPI, and small tube headers.
Kinda of a waste of heads since the TPI can't fill the runners and the runners can't fill the cylinder. Though it would be the King of all butt dynos far and wide.
I need to get these retainers sorted out it's driving me mad having these sitting here not assembled. I had planned to take them to the machine shop to have them look at them but I haven't had the time, or money. They are obviously 2 different sets of retainers but having bought them 5 years ago I doubt I can exchange them now.
#152
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Re: Ported 416 heads
Those numbers came right off the RHS website. They were obtained on a 4.200" bore fixture, which inflates the flow numbers slightly.
But even so, these do extend the useable RPM range.
Still not as good as Atilla's 457 horse TPI 383 in that best builds sticky. This cam is bigger, but a 113 lobe sep on a stroker? Even David Vizard says that's a big step in the wrong direction. Atilla's 110 is much closer to Vizard's ideal of 106, though the EFI might not work with a Vizard cam.
But even so, these do extend the useable RPM range.
Still not as good as Atilla's 457 horse TPI 383 in that best builds sticky. This cam is bigger, but a 113 lobe sep on a stroker? Even David Vizard says that's a big step in the wrong direction. Atilla's 110 is much closer to Vizard's ideal of 106, though the EFI might not work with a Vizard cam.
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Re: Ported 416 heads
I have been wrong before. I am going to look closer at that gasket. You could very well be right. Q7733SH1 is 4.100 bore dia. I searched for something else, but did not find it yet. Moot point, I think the die is cast for the 4.100 bore. Like I said, that is where I landed.
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Re: Ported 416 heads
Thanks Doom! Your the man!
I can live with those numbers, especially the RHS vortecs! If and when I get enough cash for a nice trick First Fuel Injection set-up... things will start happening! I have to admit, your right about the 305 post. I should do the 305, just because I want to.
I can live with those numbers, especially the RHS vortecs! If and when I get enough cash for a nice trick First Fuel Injection set-up... things will start happening! I have to admit, your right about the 305 post. I should do the 305, just because I want to.
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Re: Ported 416 heads
Those numbers came right off the RHS website. They were obtained on a 4.200" bore fixture, which inflates the flow numbers slightly.
But even so, these do extend the useable RPM range.
Still not as good as Atilla's 457 horse TPI 383 in that best builds sticky. This cam is bigger, but a 113 lobe sep on a stroker? Even David Vizard says that's a big step in the wrong direction. Atilla's 110 is much closer to Vizard's ideal of 106, though the EFI might not work with a Vizard cam.
But even so, these do extend the useable RPM range.
Still not as good as Atilla's 457 horse TPI 383 in that best builds sticky. This cam is bigger, but a 113 lobe sep on a stroker? Even David Vizard says that's a big step in the wrong direction. Atilla's 110 is much closer to Vizard's ideal of 106, though the EFI might not work with a Vizard cam.
#156
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Re: Ported 416 heads
Thanks Doom! Your the man!
I can live with those numbers, especially the RHS vortecs! If and when I get enough cash for a nice trick First Fuel Injection set-up... things will start happening! I have to admit, your right about the 305 post. I should do the 305, just because I want to.
I can live with those numbers, especially the RHS vortecs! If and when I get enough cash for a nice trick First Fuel Injection set-up... things will start happening! I have to admit, your right about the 305 post. I should do the 305, just because I want to.
A good aftermarket FI setup would pick that peak HP up quiet a bit by comparison.
Coming from my own mishaps I spent too many years wanting to build up a dream 350, waiting for the right parts, funds at the right time for parts, family, accidents, economy, poor timing, replacing transmissions, loosing interest because of all this crap combined; all these things including what you mentioned before can put a wrench right in the gear of your plans. That 383 could end up taking YEARS to build if your luck is anything like mine. That is why I say head and cam swap the 305, if it's low mileage/decent shape, and enjoy it while you build up the 383 on the stand.
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Re: Ported 416 heads
Holy Crap Doom! I thought I was the only one that had that problem! Always some "emergency" popping up! With gasoline at darn near $3.00 a gallon and the idiots in Washington talking about $5.00 a gallon with new taxes, my TPI 305 looks better every day! Regardless, I always liked to build stuff that was a little outside the box. I built a couple 383's back in 1975 when you had to grind your own cranks, there was literally nothing out there at any price. I am going to enjoy my little 305 and dream!
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Re: Ported 416 heads
Holy Crap Doom! I thought I was the only one that had that problem! Always some "emergency" popping up! With gasoline at darn near $3.00 a gallon and the idiots in Washington talking about $5.00 a gallon with new taxes, my TPI 305 looks better every day! Regardless, I always liked to build stuff that was a little outside the box. I built a couple 383's back in 1975 when you had to grind your own cranks, there was literally nothing out there at any price. I am going to enjoy my little 305 and dream!
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Re: Ported 416 heads
I just got off the phone with David Kauffung, the V8 rings guy who entered the 305 (306 actually) in the 2008 Engine Masters Challenge. I was able to pick his brain about the little motor that produced 394hp and to my surprise that number is from the ONE and ONLY pull that he got to do before disqualified from EMC for having a slightly wrong oil pan that gave him no advantage. Anyway, the kicker is this motor actually ended up producing 487 HP. @ 6500 and 436 lbs. per ft of torque!
I also got to find out how he fit the Fastburn heads with 2.00" 1.55" valves on there. He told me the piston height, cylinder milling, head gasket thickness and quench. Cam type, follower type and rocker arm type... etc. Now he thinking about sticking it in his Chevy 2 and taking it to the strip.
Just thought you may want to know, being we dont get much 305 info.
I also got to find out how he fit the Fastburn heads with 2.00" 1.55" valves on there. He told me the piston height, cylinder milling, head gasket thickness and quench. Cam type, follower type and rocker arm type... etc. Now he thinking about sticking it in his Chevy 2 and taking it to the strip.
Just thought you may want to know, being we dont get much 305 info.
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Re: Ported 416 heads
I think I figured it out though for my issue. I found the biggest "bottle neck" in my fund flow it's this thing called "Family". But its not all bad news I also found that I can turn that into an asset by selling them to some sweat shop; or some other sort of slave labor.
If the weather stays decent over the weekend I'm going to finish these heads. That ridge left in the bowl by the hogger is driving me nuts, it needs blended in. I was trying to avoid it but the damn thing needs to go people are PMing me about it so it's not just me that sees it. This is where porting gets "fun" all, 3 weeks worth of savings is going to have my grinder ripping away .05 inch away from it.
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Re: Ported 416 heads
Is it? Then I should stop being jealous of these guys that seem to do a LSx swap every other weekend?
I think I figured it out though for my issue. I found the biggest "bottle neck" in my fund flow it's this thing called "Family". But its not all bad news I also found that I can turn that into an asset by selling them to some sweat shop; or some other sort of slave labor.
If the weather stays decent over the weekend I'm going to finish these heads. That ridge left in the bowl by the hogger is driving me nuts, it needs blended in. I was trying to avoid it but the damn thing needs to go people are PMing me about it so it's not just me that sees it. This is where porting gets "fun" all, 3 weeks worth of savings is going to have my grinder ripping away .05 inch away from it.
I think I figured it out though for my issue. I found the biggest "bottle neck" in my fund flow it's this thing called "Family". But its not all bad news I also found that I can turn that into an asset by selling them to some sweat shop; or some other sort of slave labor.
If the weather stays decent over the weekend I'm going to finish these heads. That ridge left in the bowl by the hogger is driving me nuts, it needs blended in. I was trying to avoid it but the damn thing needs to go people are PMing me about it so it's not just me that sees it. This is where porting gets "fun" all, 3 weeks worth of savings is going to have my grinder ripping away .05 inch away from it.
#162
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Re: Ported 416 heads
I just got off the phone with David Kauffung, the V8 rings guy who entered the 305 (306 actually) in the 2008 Engine Masters Challenge. I was able to pick his brain about the little motor that produced 394hp and to my surprise that number is from the ONE and ONLY pull that he got to do before disqualified from EMC for having a slightly wrong oil pan that gave him no advantage. Anyway, the kicker is this motor actually ended up producing 487 HP. @ 6500 and 436 lbs. per ft of torque!
I also got to find out how he fit the Fastburn heads with 2.00" 1.55" valves on there. He told me the piston height, cylinder milling, head gasket thickness and quench. Cam type, follower type and rocker arm type... etc. Now he thinking about sticking it in his Chevy 2 and taking it to the strip.
Just thought you may want to know, being we dont get much 305 info.
I also got to find out how he fit the Fastburn heads with 2.00" 1.55" valves on there. He told me the piston height, cylinder milling, head gasket thickness and quench. Cam type, follower type and rocker arm type... etc. Now he thinking about sticking it in his Chevy 2 and taking it to the strip.
Just thought you may want to know, being we dont get much 305 info.
That's awesome man great info there.
I was trying to not talk about it but since it's here I am going to work on my RS TBI next summer and wanted to make a project out of it to see how/if some good 180-190cc 2.02 1.6 valve heads work with a mild/wild cam. My plan was ported Vortec, or aftermarket whatever is pliable at the time.
TxTtopZ PM me the details would you?
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Re: Ported 416 heads
NICE!!
That's awesome man great info there.
I was trying to not talk about it but since it's here I am going to work on my RS TBI next summer and wanted to make a project out of it to see how/if some good 180-190cc 2.02 1.6 valve heads work with a mild/wild cam. My plan was ported Vortec, or aftermarket whatever is pliable at the time.
TxTtopZ PM me the details would you?
That's awesome man great info there.
I was trying to not talk about it but since it's here I am going to work on my RS TBI next summer and wanted to make a project out of it to see how/if some good 180-190cc 2.02 1.6 valve heads work with a mild/wild cam. My plan was ported Vortec, or aftermarket whatever is pliable at the time.
TxTtopZ PM me the details would you?
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Re: Ported 416 heads
TC Ttop Z That is what I am talking about! I LOVE IT when someone gets that kind of power out of a so called "Piece of crap" engine! So my hopes for 275 RWHP is not a pipe dream? I would like to hear the specifics of the build. Thanks!
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#166
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Re: Ported 416 heads
I hear ya mlynch things work that way around here too.
I was going to blend the ridges cut by the bowl hog this weekend but said screw it and done it this evening. If anyone's interested I can post some pics of the bowls now.
Being half tarded I didn't wear my goggles and got a nice chunk of metal stuck in my eye now.. Usually a nice strong magnet (pro tip for ya) will fix this but it's back in there good. I have pulled some nasty messes of metal out of my eye using a magnet, I don't like to wear goggles so I've done it a quiet a few times now. If I'm doing cuts where it's flinging metal at my face I always stop and put them on though but sometimes that rogue piece sneaks in when the other shards are flying a different direction. You should always wear ear and dust mask though. You should probably always wear eye protection too but I want to see what is going on very clearly.
I was going to blend the ridges cut by the bowl hog this weekend but said screw it and done it this evening. If anyone's interested I can post some pics of the bowls now.
Being half tarded I didn't wear my goggles and got a nice chunk of metal stuck in my eye now.. Usually a nice strong magnet (pro tip for ya) will fix this but it's back in there good. I have pulled some nasty messes of metal out of my eye using a magnet, I don't like to wear goggles so I've done it a quiet a few times now. If I'm doing cuts where it's flinging metal at my face I always stop and put them on though but sometimes that rogue piece sneaks in when the other shards are flying a different direction. You should always wear ear and dust mask though. You should probably always wear eye protection too but I want to see what is going on very clearly.
#168
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Re: Ported 416 heads
210cc is a bit overboard you would think it would want to spin to 8000-9000RPM to use that space.
I'm going to attach a DD screen shot of what I was talking about before the big valve effect on a 305. This only seems to make a great difference with very good flowing heads a medium lift. I'm using the RHS Vortec 2.02 heads since they have such potential at .4 lift. Using other awesome heads this works too. They are being compared to TFS 175 Super 23 heads with 1.94 intakes.
Now I'm not posting this to say, "do this and this is what you get", we all know DD is just a toy that crunches equaisions, it shows "potential". I just want to show the effect behind the math, the effect is just like increasing displacement. Where usually a head or cam change you loose something somewhere and gain somewhere else this just gains all over.
Here's the thing that takes it for me. The RHS Vortec headed motor is using a XE256 cam (VERY mild, negative overlap), and the TFS headed is using a XE268 to make those peaks everything else is identical.
I'm going to attach a DD screen shot of what I was talking about before the big valve effect on a 305. This only seems to make a great difference with very good flowing heads a medium lift. I'm using the RHS Vortec 2.02 heads since they have such potential at .4 lift. Using other awesome heads this works too. They are being compared to TFS 175 Super 23 heads with 1.94 intakes.
Now I'm not posting this to say, "do this and this is what you get", we all know DD is just a toy that crunches equaisions, it shows "potential". I just want to show the effect behind the math, the effect is just like increasing displacement. Where usually a head or cam change you loose something somewhere and gain somewhere else this just gains all over.
Here's the thing that takes it for me. The RHS Vortec headed motor is using a XE256 cam (VERY mild, negative overlap), and the TFS headed is using a XE268 to make those peaks everything else is identical.
#169
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Re: Ported 416 heads
I got one of the heads together this evening after sorting out the retainer issue. After verifying that they were the correct dimensions just poor quality control I'm using the 8 that install higher on the intakes and the 8 that install lower on the exhaust to help compensate for the deeper spring pockets on the exhaust springs.
Also I ended up using -0.060 locks on all valves. I used stock size positive seals on both int and exh, the exh seals were roughed very slighting with 60grit.
Final retainer-->seal clearance is .532 exh, .552 int.
That only leaves a .052 room for error on exhaust side (cam is .480)
The chamber measures 3.843 at it's widest after the machine work so I will definitely be notching the intake valve on the block since it's standard bore, standard deck height.
Also I ended up using -0.060 locks on all valves. I used stock size positive seals on both int and exh, the exh seals were roughed very slighting with 60grit.
Final retainer-->seal clearance is .532 exh, .552 int.
That only leaves a .052 room for error on exhaust side (cam is .480)
The chamber measures 3.843 at it's widest after the machine work so I will definitely be notching the intake valve on the block since it's standard bore, standard deck height.
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Re: Ported 416 heads
I got one of the heads together this evening after sorting out the retainer issue. After verifying that they were the correct dimensions just poor quality control I'm using the 8 that install higher on the intakes and the 8 that install lower on the exhaust to help compensate for the deeper spring pockets on the exhaust springs.
Also I ended up using -0.060 locks on all valves. I used stock size positive seals on both int and exh, the exh seals were roughed very slighting with 60grit.
Final retainer-->seal clearance is .532 exh, .552 int.
That only leaves a .052 room for error on exhaust side (cam is .480)
The chamber measures 3.843 at it's widest after the machine work so I will definitely be notching the intake valve on the block since it's standard bore, standard deck height.
Also I ended up using -0.060 locks on all valves. I used stock size positive seals on both int and exh, the exh seals were roughed very slighting with 60grit.
Final retainer-->seal clearance is .532 exh, .552 int.
That only leaves a .052 room for error on exhaust side (cam is .480)
The chamber measures 3.843 at it's widest after the machine work so I will definitely be notching the intake valve on the block since it's standard bore, standard deck height.
When I spoke with Kauffung on the bore notching he specified that he left 1/8" off material between the notch and the top ring. So be careful there.
The only thing I can see is on the picture of the head thats showing the studs, about the 4th stud over has some groove around it. What the hell is that?
#171
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Re: Ported 416 heads
That should be enough clearance I would think. Not that far off from .062" which is ideal. Some say more but whatever.
When I spoke with Kauffung on the bore notching he specified that he left 1/8" off material between the notch and the top ring. So be careful there.
The only thing I can see is on the picture of the head thats showing the studs, about the 4th stud over has some groove around it. What the hell is that?
When I spoke with Kauffung on the bore notching he specified that he left 1/8" off material between the notch and the top ring. So be careful there.
The only thing I can see is on the picture of the head thats showing the studs, about the 4th stud over has some groove around it. What the hell is that?
I don't plan on going crazy with the cut in the block nothing like I would do for a 2.01 valve.
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Re: Ported 416 heads
Do you need some pics of 305 decks that have been notched? I have some from David and then the other is from Willie.
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Re: Ported 416 heads
sure seeing what they did would be useful. I had the head on the block today and took some measurements and plotted things out.
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Re: Ported 416 heads
Head #2 is done and now they are ready for me to do something with them.
Still waiting on those pic TxTtopZ I think you forgot..
Now what heads do I port next? I'm thinking 059's (Vortec 305) or maybe even selling one of the kids for aftermarket cores to port. I would love to know how many CC the 059 intake runner is it would help a lot with deciding because I want to finish around 180cc and 2.01 1.6 valves.
Still waiting on those pic TxTtopZ I think you forgot..
Now what heads do I port next? I'm thinking 059's (Vortec 305) or maybe even selling one of the kids for aftermarket cores to port. I would love to know how many CC the 059 intake runner is it would help a lot with deciding because I want to finish around 180cc and 2.01 1.6 valves.
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Re: Ported 416 heads
Head #2 is done and now they are ready for me to do something with them.
Still waiting on those pic TxTtopZ I think you forgot..
Now what heads do I port next? I'm thinking 059's (Vortec 305) or maybe even selling one of the kids for aftermarket cores to port. I would love to know how many CC the 059 intake runner is it would help a lot with deciding because I want to finish around 180cc and 2.01 1.6 valves.
Still waiting on those pic TxTtopZ I think you forgot..
Now what heads do I port next? I'm thinking 059's (Vortec 305) or maybe even selling one of the kids for aftermarket cores to port. I would love to know how many CC the 059 intake runner is it would help a lot with deciding because I want to finish around 180cc and 2.01 1.6 valves.
Sorry about the pics, I have been working a lot and things have been crazy. I will post them as soon as I get to the house.
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Re: Ported 416 heads
I was looking over that 487hp 305 again early and man that is a nice motor for what he put into it. Stock block, crank, rods and cheapo hyper pistons. Better heads, bigger valves, and less duration cam and full roller valve train I bet ya it would hit 500hp at the same RPM.
He basically zero decked the block, took .030 off the head deck and still managed .600 lift with 2.00 intake valves. Now if you don't deck the block or mill the heads and DO notch the block I can see a bigger valve working easily.
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Re: Ported 416 heads
Ooops did I say that? That's the downfall of typing +60wpm is everything you think comes flying out of your fingers.
I was looking over that 487hp 305 again early and man that is a nice motor for what he put into it. Stock block, crank, rods and cheapo hyper pistons. Better heads, bigger valves, and less duration cam and full roller valve train I bet ya it would hit 500hp at the same RPM.
He basically zero decked the block, took .030 off the head deck and still managed .600 lift with 2.00 intake valves. Now if you don't deck the block or mill the heads and DO notch the block I can see a bigger valve working easily.
I was looking over that 487hp 305 again early and man that is a nice motor for what he put into it. Stock block, crank, rods and cheapo hyper pistons. Better heads, bigger valves, and less duration cam and full roller valve train I bet ya it would hit 500hp at the same RPM.
He basically zero decked the block, took .030 off the head deck and still managed .600 lift with 2.00 intake valves. Now if you don't deck the block or mill the heads and DO notch the block I can see a bigger valve working easily.
Pictures of 305 bore notches courtesy of Willie (yes, awesome supercharged IROC Willie) and David Kauffung who has now the highest HP (proven anyway) 305 in NA form that runs on pump gas.
Dont sweat the kids comment, were all guilty here, hell my wife says it all the time.
So - notice how the kauffung block is notched on BOTH sides using fastburns and 2.00/1.55's and ******* is just on one side using 1.94/1.55's and AFR heads.
Last edited by TxTtopZ; 10-20-2010 at 08:42 AM.
#178
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Re: Ported 416 heads
Looks like Willie swept for the chamber and David's was for the valves. Makes sense for a forced induction I guess.
Not sure why David did the exhaust side of the bore though, but who knows it may have helped.
That pic of his 305 there was the early work he did end up over boring and decking and changing things for the 2008 EMC it looks like. If he really picked up what he claimed I bet you he went a little more aggressive on the notches letting the head breath into the bore more.
I would like to find a documented dyno pull of the later version of his 305 toy. The early build he did entered in 2007 EMC made 394hp @ 6300 RPM though.
Not sure why David did the exhaust side of the bore though, but who knows it may have helped.
That pic of his 305 there was the early work he did end up over boring and decking and changing things for the 2008 EMC it looks like. If he really picked up what he claimed I bet you he went a little more aggressive on the notches letting the head breath into the bore more.
I would like to find a documented dyno pull of the later version of his 305 toy. The early build he did entered in 2007 EMC made 394hp @ 6300 RPM though.
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Re: Ported 416 heads
Looks like Willie swept for the chamber and David's was for the valves. Makes sense for a forced induction I guess.
Not sure why David did the exhaust side of the bore though, but who knows it may have helped.
That pic of his 305 there was the early work he did end up over boring and decking and changing things for the 2008 EMC it looks like. If he really picked up what he claimed I bet you he went a little more aggressive on the notches letting the head breath into the bore more.
I would like to find a documented dyno pull of the later version of his 305 toy. The early build he did entered in 2007 EMC made 394hp @ 6300 RPM though.
Not sure why David did the exhaust side of the bore though, but who knows it may have helped.
That pic of his 305 there was the early work he did end up over boring and decking and changing things for the 2008 EMC it looks like. If he really picked up what he claimed I bet you he went a little more aggressive on the notches letting the head breath into the bore more.
I would like to find a documented dyno pull of the later version of his 305 toy. The early build he did entered in 2007 EMC made 394hp @ 6300 RPM though.
Sorry, I know theres no need to "quote" everything you say but I figure the notification email is nice...
David said he did a little clean up on the heads if I remember correctly and also the initial pull for EMC had a different (smaller) cam and had the smaller 1.65 rocker arms on both intake and exhaust...not the others.. I could see that being worth that amount of hp given the original cam was only a 110 or 112 LSA and the bigger one was a 106 or 108. You are not the only one who would like to see that pull.
I want to see what your heads flow.....
#180
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Re: Ported 416 heads
Getting them flow tested would be great but spending $50 to have it done that could be spent on $50 head gaskets doesn't sound good right now. If I could find a place to do it around SE or central OH for less I wouldn't mind. It looks like a time consuming process though so the cost is understandable.
I was going to PM you this info TxTtop since you seem to be the only one interested in porting heads but someone may be reading this stuff.
I took some measurements in the runner that you may find useful.
Port entry widest: 2.08 x 1.25
Pushrod Pinch narrowest: .975 @ .75 deep
Short turn/Floor ramp narrowest: 1.501 @ 2.33 deep
The height of the intake was consistent well into the port. It was 2.03 at the PRP choke and deeper.
Here's a thread that has other peoples ported 416 head dimensions and flow. https://www.thirdgen.org/forums/tech...w-numbers.html
I was going to PM you this info TxTtop since you seem to be the only one interested in porting heads but someone may be reading this stuff.
I took some measurements in the runner that you may find useful.
Port entry widest: 2.08 x 1.25
Pushrod Pinch narrowest: .975 @ .75 deep
Short turn/Floor ramp narrowest: 1.501 @ 2.33 deep
The height of the intake was consistent well into the port. It was 2.03 at the PRP choke and deeper.
Here's a thread that has other peoples ported 416 head dimensions and flow. https://www.thirdgen.org/forums/tech...w-numbers.html
Last edited by Doom86; 12-15-2010 at 01:03 PM. Reason: bad caliper
#181
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Re: Ported 416 heads
(bore x bore x stroke x rpm x .00353)/614
Using this equation you can determine the proper Cross Sectional Area at the choke in the runner per what RPM peak you are shooting for. In a SBC head it's going to be at the PRP area.
I'm not going to repeat everything I've learned about it, hopefully someone like COUCH or the like who knows exactly what the benefits of proper CSA are can. In short once you have fully ported the head adjusting the CSA accordingly will give the fastest overall motor for that RPM. You always want to error on the short side, never over because too little CSA leads to lower port efficiency, it's loosing torque/hp when you don't need be to achieve the same peak RPM.
Here is what I ended up with. Also posting 305ci and 350ci CSA needs per RPM.
PRP choke 1.935 x .975 = 1.88 CSA (we could go max 2.184 w/ this head)
305
(bore x bore x stroke x rpm x .00353)/614
3.735 x 3.735 x 3.480 x 6000 x .00353 /614 = 1.675
3.735 x 3.735 x 3.480 x 6500 x .00353 /614 = 1.814
3.735 x 3.735 x 3.480 x 7000 x .00353 /614 = 1.954
3.735 x 3.735 x 3.480 x 7500 x .00353 /614 = 2.093
350
4.000 x 4.000 x 3.480 x 5000 x .00353 /614 = 1.601
4.000 x 4.000 x 3.480 x 5500 x .00353 /614 = 1.761
4.000 x 4.000 x 3.480 x 6000 x .00353 /614 = 1.921
4.000 x 4.000 x 3.480 x 6500 x .00353 /614 = 2.081
4.000 x 4.000 x 3.480 x 6750 x .00353 /614 = 2.161
So the max RPM;
305ci @ 6,700 RPM
350ci @ 5,800 RPM
400ci @ 5,000 RPM
The potential is there for a 6750RPM 350 if you want it too, there is a lot of metal left in the push rod pinch. But I think I went a bit overboard for my 305 build?
Using this equation you can determine the proper Cross Sectional Area at the choke in the runner per what RPM peak you are shooting for. In a SBC head it's going to be at the PRP area.
I'm not going to repeat everything I've learned about it, hopefully someone like COUCH or the like who knows exactly what the benefits of proper CSA are can. In short once you have fully ported the head adjusting the CSA accordingly will give the fastest overall motor for that RPM. You always want to error on the short side, never over because too little CSA leads to lower port efficiency, it's loosing torque/hp when you don't need be to achieve the same peak RPM.
Here is what I ended up with. Also posting 305ci and 350ci CSA needs per RPM.
PRP choke 1.935 x .975 = 1.88 CSA (we could go max 2.184 w/ this head)
305
(bore x bore x stroke x rpm x .00353)/614
3.735 x 3.735 x 3.480 x 6000 x .00353 /614 = 1.675
3.735 x 3.735 x 3.480 x 6500 x .00353 /614 = 1.814
3.735 x 3.735 x 3.480 x 7000 x .00353 /614 = 1.954
3.735 x 3.735 x 3.480 x 7500 x .00353 /614 = 2.093
350
4.000 x 4.000 x 3.480 x 5000 x .00353 /614 = 1.601
4.000 x 4.000 x 3.480 x 5500 x .00353 /614 = 1.761
4.000 x 4.000 x 3.480 x 6000 x .00353 /614 = 1.921
4.000 x 4.000 x 3.480 x 6500 x .00353 /614 = 2.081
4.000 x 4.000 x 3.480 x 6750 x .00353 /614 = 2.161
So the max RPM;
305ci @ 6,700 RPM
350ci @ 5,800 RPM
400ci @ 5,000 RPM
The potential is there for a 6750RPM 350 if you want it too, there is a lot of metal left in the push rod pinch. But I think I went a bit overboard for my 305 build?
Last edited by Doom86; 12-15-2010 at 01:14 PM. Reason: stupid caliper
#182
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Re: Ported 416 heads
I want to update this just to keep things accurate. The cross sectional info on the heads was wrong because the caliper I was using is defective between .959-1.1in. The "real" CSA is a bit different then what I got before.
Also I'll dump the last good pics I got right after I bowl blended and before assembly. I do think I should have gone with a bigger intake valve, or better yet cut for the valve before I ported so there's no guessing.
before/after bowl blending
digital zoom = win
Also I'll dump the last good pics I got right after I bowl blended and before assembly. I do think I should have gone with a bigger intake valve, or better yet cut for the valve before I ported so there's no guessing.
before/after bowl blending
digital zoom = win
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Re: Ported 416 heads
Im so jealous! The time you have put in these heads is astronomical! I have a lead on some Vortec 062's from GM, brand new, assembled for $400.00 on a payment plan. I have one more day to see if the other guy falls through... I am PRAYING he gets a hot date a blows his money!!
#184
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Re: Ported 416 heads
It feels like short of eternity
Porting heads keeps broke gear heads busy though.
It's happening though man check out my 305 build TxTtop.
Why not go with them EQ's on Ebay for 100$?? They will bolt up to your intake no problem right?
Porting heads keeps broke gear heads busy though.
It's happening though man check out my 305 build TxTtop.
Why not go with them EQ's on Ebay for 100$?? They will bolt up to your intake no problem right?
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Re: Ported 416 heads
What EQs for 100?????
I will check out the build fo sho..,.. ditto on the broke gear head... Christmas is about to make it REALLY tight
#187
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Re: Ported 416 heads
100$ each and aftermarket casting with 69-86 intake bolt pattern.. Perfect for what you want?
Hell you could sell your L31 and fund the whole deal.
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Re: Ported 416 heads
Like the build, always neat to see something done with pieces that arent so popular just for curiosities sake...and being car poor we all get that.
Wish there was some way you could have one cyl flowed on those at least would be nice info to have and share.
Held my breath for a page or two there as you kept "having to go over again" lol....and you didnt hit water thank God. btdt.
How do you like those black boogers? Cast iron, ugh.
Wish there was some way you could have one cyl flowed on those at least would be nice info to have and share.
Held my breath for a page or two there as you kept "having to go over again" lol....and you didnt hit water thank God. btdt.
How do you like those black boogers? Cast iron, ugh.
#189
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Re: Ported 416 heads
I've ported a set indoors with no mask I can tell you about some black boogers. That crap will make you sick too if you get too much.
The worst of it was the very last time I had the grinder on them I couldn't be bothered with goggles and took a blast of metal shards to the eye that was there for days, and a shard stuck into my eyeball. That was NOT cool. Usually a magnet helps but I finally fished the last 4 pieces out after several eye flushes and swabs.
I would like to get them flow tested but can't find anyone around here. Even talked to my machinist and he didn't know anyone either. Did some searching online and it turned up nothing. If anyone knows someone who knows someone who may know a guy with a reputable flow bench around SE or central Ohio let me know.
The way I see it this car, these heads, all of this crap would just be sitting there collecting dust I may as well enjoy them and make something out of it.
The worst of it was the very last time I had the grinder on them I couldn't be bothered with goggles and took a blast of metal shards to the eye that was there for days, and a shard stuck into my eyeball. That was NOT cool. Usually a magnet helps but I finally fished the last 4 pieces out after several eye flushes and swabs.
I would like to get them flow tested but can't find anyone around here. Even talked to my machinist and he didn't know anyone either. Did some searching online and it turned up nothing. If anyone knows someone who knows someone who may know a guy with a reputable flow bench around SE or central Ohio let me know.
The way I see it this car, these heads, all of this crap would just be sitting there collecting dust I may as well enjoy them and make something out of it.
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Re: Ported 416 heads
http://cgi.ebay.com/ebaymotors/CHEVR...Q5fAccessories
Wow, the price is right, if these are legit
This might be wrong and irrelevant, but I was under the impression that vortec heads have a "taller" intake port? How well would an earlier style intake manifold work with them then?
Wow, the price is right, if these are legit
This might be wrong and irrelevant, but I was under the impression that vortec heads have a "taller" intake port? How well would an earlier style intake manifold work with them then?
#191
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Re: Ported 416 heads
The dimensions of the port are no taller then a performer RPM runner. But the placement of the GM casting is off a bit if I'm not mistaken.
These are not GM castings though so that doesn't matter. They are cast for pre-87 intakes.
If I had the extra cash I would pick up a pair for my daily driver but can't even consider that at the moment.
These are not GM castings though so that doesn't matter. They are cast for pre-87 intakes.
If I had the extra cash I would pick up a pair for my daily driver but can't even consider that at the moment.
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Re: Ported 416 heads
Hmmm, okay. That's good to know.
That's how it is with the 4.3 V6 vortec anyway. Not only are the bolt angles off, but the ports & even gasket surfaces don't match up between the pre '96 heads and the later "true" vortec heads IIRC. Pretty sure the ports at least are off
That's a great deal on those heads then, seems too good to be true honestly
That's how it is with the 4.3 V6 vortec anyway. Not only are the bolt angles off, but the ports & even gasket surfaces don't match up between the pre '96 heads and the later "true" vortec heads IIRC. Pretty sure the ports at least are off
That's a great deal on those heads then, seems too good to be true honestly
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Re: Ported 416 heads
http://cgi.ebay.com/ebaymotors/CHEVR...Q5fAccessories
Wow, the price is right, if these are legit
This might be wrong and irrelevant, but I was under the impression that vortec heads have a "taller" intake port? How well would an earlier style intake manifold work with them then?
Wow, the price is right, if these are legit
This might be wrong and irrelevant, but I was under the impression that vortec heads have a "taller" intake port? How well would an earlier style intake manifold work with them then?
It is "legit", I bought the same heads from the same company 2 years ago, although I paid a LOT more than this!!! (I am not complaining! They were a bargain when I bought them)! I have these installed on my 85 305 ElCamino with a '92 TPI.
While the bolt pattern IS "early" the ports are taller than the early GM port. I had to have the TPI base welded and then raise the ports to cover the tops of the intake. It was a lot of work, but it is quite effective. I have a 9.5 C/R bigger valves, screw in studs, Thick Decks, Perimeter Valve covers, Raised valve cover rails, Vortec Chambers and really good "As Cast" ports. So the work of not having to port offsets the cost of modifying the intake. These heads have BEAUTIFUL ports and bowls. Everything is smooth and symetrical; not polished, but for as cast, they are fine! I am not saying that they could not be improved, but for a 310 CID SBC, they flow plenty of air "as is"!!! There is NO WAY to duplicate even the Screw in studs for the price of these heads!
I did automotive machine work for many years and the workmanship on these heads is FAR above what you see on most OEM heads! I would snap these up in a heartbeat if I needed another set! $260 for TWO brand new heads! That is unheard of! The best thing is that they are NOT "Made in China"! There are a lot of "cheap" performance parts that come from China, and most are of VERY Questionable quality!
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Re: Ported 416 heads
If you look on their website they have 4-5 different versions of this head and they have been updating the castings frequently it looks like. That's saying a lot since most "big names" are still on 15 year old designs.
I would definitely give them a call and see if these have the same problem mlynch described though. There's so many different versions and revisions it's hard to know if you'll have the same problem.
I would definitely give them a call and see if these have the same problem mlynch described though. There's so many different versions and revisions it's hard to know if you'll have the same problem.
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Re: Ported 416 heads
I cannot believe my eyes! Says no returns at the bottom... not trying to knit pick the heads, but seriously??? 100 each??? I feel like Kung Fu Panda with a dumpling!
Maybe someone should call Don over at EQ and see what the deal is??
Oh, as for getting the heads flow tested. For the love of God, get'r done!
Maybe someone should call Don over at EQ and see what the deal is??
Oh, as for getting the heads flow tested. For the love of God, get'r done!
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Re: Ported 416 heads
I mis-read the description, these are "centerbolt only" valve cover heads, otherwise the same as what I bought and have described. My heads were the perimeter bolt valve cover heads.
#197
Re: Ported 416 heads
http://cgi.ebay.com/ebaymotors/CHEVR...Q5fAccessories
100$ each and aftermarket casting with 69-86 intake bolt pattern.. Perfect for what you want?
Hell you could sell your L31 and fund the whole deal.
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Re: Ported 416 heads
YES! I have the same heads (except perimeter valve cover bolts) on a TPI 305. 64cc + .030 over + .015 head gasket + KB 2 valve relief Hyper pistons -.025 down the hole makes 9.5 to 1. I wanted something that could get by on 87 octane gas in a pinch. Not High Compression, but the breathing ability of the larger ports and valves matched my engine requirements perfectly. The flow of these heads at .500 and less lift is spectacular, so they work well in a mild street engine with a mild camshaft. If I would want more compression, I could have milled them if I wanted to raise the ratio up to 10.0 to one or higher. Plenty of deck to mill on these heads.
#199
Re: Ported 416 heads
YES! I have the same heads (except perimeter valve cover bolts) on a TPI 305. 64cc + .030 over + .015 head gasket + KB 2 valve relief Hyper pistons -.025 down the hole makes 9.5 to 1. I wanted something that could get by on 87 octane gas in a pinch. Not High Compression, but the breathing ability of the larger ports and valves matched my engine requirements perfectly. The flow of these heads at .500 and less lift is spectacular, so they work well in a mild street engine with a mild camshaft. If I would want more compression, I could have milled them if I wanted to raise the ratio up to 10.0 to one or higher. Plenty of deck to mill on these heads.
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Re: Ported 416 heads
I have not done the math on that. If you are shooting for 58 cc chambers, I would look for something smaller to start with, it will take a fair amount of milling on these heads to get to 58 cc chambers which can create other issues. I would choose a piston that would supply the additional dome volume, rather than milling a lot off of the head. Milling would be my LAST choice if I could not make up the compression some other way. Not saying it CANNOT be done, only that it would be my LAST choice.
The 64cc chambers on these heads was a slight negative, however, I was able to reach my target compression ratio AND squish clearance without any milling. I wanted a VORTEC Chamber AND High Flow ports and larger valves in an OLD School "Non-Vortec" pattern head.
My targets were:
C/R => 9.5 to 1
Chamber type = VORTEC
INTAKE Port volume => 170-180 cc
INTAKE Valve dia. = 1.9375
Quench Clearance = .040 (ideal) - .045(max)
Valve cover = Perimeter bolts
No heat crossover and screw in studs were icing on the cake!
The 64cc chambers on these heads was a slight negative, however, I was able to reach my target compression ratio AND squish clearance without any milling. I wanted a VORTEC Chamber AND High Flow ports and larger valves in an OLD School "Non-Vortec" pattern head.
My targets were:
C/R => 9.5 to 1
Chamber type = VORTEC
INTAKE Port volume => 170-180 cc
INTAKE Valve dia. = 1.9375
Quench Clearance = .040 (ideal) - .045(max)
Valve cover = Perimeter bolts
No heat crossover and screw in studs were icing on the cake!