Back in the 80's we used to rebuild the stone holders to save money, Goodson was pricey then too. It is good that you tell people how much you have to invest to get the job done right.

Here in Australia, one of the shops down in Melbourne do CNC cast iron porting on the Holden 304 heads, they say they have a Newen single point too, but they probably have a Serdi as well, I think the cast iron heads would be done on the older machine. Then there is Tony Knight in Adelaide, he does heaps of online write ups of his work, very good porter, from what I've seen he does his 3 angle jobs with separate cutters not the combo ones.

I have an old set of 882 heads I ported years ago. They have all the basic upgrades. 2.02/1.60 valves, screw in studs and guide plates. I lapped the valves. I used heavier grit and then finer grit. I cleaned them and then used alcohol to check seal. Seemed to work. But a lot of work. I know the valves sealed really well.

THANKS FOR THE $ LESSON. Cheers from Calgary.

I have used AFR 195 SBC heads out of the box with perfect results. However I did take the time to check a few of the valve springs for proper installed height and seat and open pressure. They were spot on. I also checked to see how clean the heads were and how free they were of any kind of machining debris. This was also very successful in that they were squeaky clean with no chips or other bad things. I also have had the same result with some AFR SBF 185 cc heads. They also were clean and perfect right out of the box. However I have also used some Dart heads, Iron Eagles, that were full of chips and had to be disassembled and cleaned thoroughly before they could used. It is very important to check them all but my experience with the AFR products was impressive. And they all made excellent power on their destined engines.

Exactly. Well said. I have been grinding seats since 1978. Before i got my sioux seat grinder and valve refacer i did some creative lapping. I was mostly doing 461 291 and 441 sbc heads i took some used valves and welded a 3/8 nut to the center of the head. Had the machine shop grind 45, 30 and 60 angles. That allowed me to control the seat widths and position before i even dropped the actual valve i was going to run in. I was so upset a few years ago. The diesel shop next door owner died. They were selling off equipment. They ended up tossing an entire sioux bench. Seat grinder and valve refacer in the massive scrap bin . The son said. Who grinds valves anymore. I did at least end up with a straight drive kwikway seat grinder kit with a broken flex coupling and thousands of dollars of portapower rams and pumps.

This was a great video! And one of those promaxx set of heads you just finished was mine lol now I see what a pain they are!

This is why you're hand porting my promaxx heads love the content

The port’s look pretty nice can’t wait till your done ! 👍

My friend that is an engine builder has to check every head. He has even found retainers and locks that he did not like and changed them. Let alone what you found with valves sealing.

The costs of the machinists tools have to be a contributing factor as to why there aren’t many new machinists.

Thank you for your knowledge and video's USA 🇺🇸

Bought a full OLD set of stones, pilots, dresser, driver, stone arbors and carry case for less than $300. It was dirty but all there. I learned that system in tech school back in the 80s. I scored a seat and guide set for under $200 on snee bay, no one else even bid on it. Its not the big specialized mill but mounts to the head deck. Lastly a old Black and Decker valve grinder that ran but needed a cast iron bracket rewelded, $150. My point, this equipment is old, slow, but very good quality. I have a few cracked heads saved for test porting and practice. I only really use this equipment on my own extreme budget projects. Customers work still goes to a pro shop.

If you are not already aware, seat profile cutters can be ground on different back angles. Newen offers them at 12, 10, and 8 degree. Probably, Serdi does also... I usually get them in 8 degrees, and it really helps with certain seat materials. I bought Newen's computer cutter design program, and they waive the custom drawing fee for life. Something to try if you already haven't. Some people use a machining aid also, I haven't really tried that, though.

Trickflow heads are usually ready to go out of the box. I say that based on several sets I’ve used for LS engines.

At 11:55, in addition to the Visual Skipping lapping Mark, Could you also show how a valve seat Concentricity gauge Shows an Unacceptable Out of Spec (Maybe > 0.002") Measurement reading ?? .....Thx for sharing the good info.....

I used to have people ask how come it costs so much to have a head done 😂 after finding how much the machines cost no wonder, thanks for sharing, all the best to you and your loved ones

A tip for fine lapping compund is the Tormek PA-70 honing compound. Its around 3 microns grain size. Maybe not right for seats this hard but still.

Definitely appreciate the wanna do it right attitude, but will those heads still seal just the same after the series of Dyno pulls your planning. That would be interesting if you checked that afterwards

At least the seat to chamber looks nice on the intake side. Looks like no ridge there. From what i could see in the video anyway. I've made it a "good business decision" to send every head to my machine shop for a valve job. No matter the manufacturer. You only get burned once to learn your lesson when an engine under performs or fails to start from poor sealing valves. Good video Eric.

How about a video on valve contact location for the best flow?

hard is brittle were not well-tite fun (and other nickel alloy seats) I like the dura bond sintered seats for users dura bond will recommend which line to use for industrial use we used the harder to machine ones sharp yes but feed and lube counts (using Serdi last many years but sstill have several stone systms

When running there is heat variation across the valves and seats. Cold intake coming in, hot exhaust going out. One seat side hotter than the other. AND the valve stem distorts. As you say Eric.... Theres still 20 difference!!!👍

Well I learned some more stuff for sure. Um dang there is a lot of material difference it sounds like but I do got a question let's say on a daily driver you want your head to last long as possible to stay sealing like I don't know a 6.0l LS Chevy truck 300,000 to 500,000 miles let just say what material would you use for make it long on daily driver vehicles

I learn things when you rant

Even though I know, it’s not perfect. I’ve used the heavier grit and then going to the lighter grit to fix minor imperfections, but only minor imperfections.

I have used afr cnc 195 heads out the box, i have also used brodix dragon slayers out the box without issue, maybe im lucky

I dont care who makes them , I ALWAYS check them completely . valves , springs , complete tear down no shortcuts. And yes I port cast iron heads. LOL

If they are AFR heads,,,YES

That clover lapping compound isn't $20 anymore. A big can is now almost $70 on mc master carr. Keep the videos coming.

Memories of the old Martin Wells seats...

This reminds of a video a youtuber in Georgia made a few years back did. Check everything...

Eric your problem with cutting the hard valve seats is all about tool pressure....that's how the people who are cutting them are getting them cut. You can get there several different ways. 1: low spindle speed, high feed. 2 High spindle speed, high feed. 3: Varying spindle speed throughout the cut to break up the harmonics. 4: in some cases a very high spindle speed and extremely low feed rate will get you there. If the company that you buy your custom inserts from can build you a positive rake insert it will help to clear the chips and load the cutter slightly more than a neutral rake insert.

Eric, When Vac testing a valve Seat, besides pulling "Finger" Peak test Psi (25 or so) within 1 Psi, in addition When pump is turned Off, Shouldn't the gauge take a certain Minimum amount of Time to gradually drop to 10 Psi Below Test reading ?? .....I have Seen good Valves & Seats within 0.002" Without springs & dry (No Oil film) Hold constant Peak vacuum for over 40 seconds to Drop -10 Psa numbers....Thx for all Excellent info.....

Question on vacuum testing. Because you test the vacuum on the heads when they are cold, will it make any difference when the heads are up to operating temp, being that the clearances will open ?

Is it possible the seat is not installed completely??

Sounds like Superman

What's your take on the Neway valve seat cutters?

the stone holder is around 250 bucks, in case anyone's curious... (had to buy one quite literally last week) lol ... crazyness!

When you say you flow every head you sell, do you mean all four intake and exhaust ports or just number 1? And do you do that vacuum test on every port? The difference between pass and fail was so tiny on that little gauge. I had to watch several times and even then I would not be able to see which ones were passing. Not from where the camera was letting me see, at least. As a consumer: The best I could hope to do would be to turn the heads upside down and pour some solvent in the combustion chambers and wait to see if it trickles out the port. If I take some heads in for a valve job to the local Joe Sixpack machine shop, do you think they do a vacuum test to verify whether they seal?

Oof, looks like the seats were ground(poorly) for a 2.1 valve. Tough break

great video, just want to let ya know im an amsoil dealer if you need anything let me know ill get whatever ya need at cost

Out here doing the lords work 🙏

Eric, is there a way to check valve seal without vacuum? I seen it done with water or is the way only to lap them and check contact pattern?

Eric If someone ran them for prolonged period with fixing it considering how hard that seat is What would most likely happen?

How about showing the vacuum test on a set of heads and the bolting them to the block and doing the vacuum test again before any valve train or manifolds are installed, those seats don't stay round when the heads are torqued.

Once you get those hard seats cut, how do they last, do they chip from being to hard,?

Off topic question.....Will a small bore long stroke make more power than a short stroke large bore.?

Not really a glowing recommendation for promaxx. I mean if the chinesium heads are cheaper to make in China, and then they finish machining here, and then you have to have all this done to make them work right. And it’s not like the big names like afr, brodix or dart aluminum heads are not made in China and finished machined here, they may have the same issue. I really miss Dart cast iron heads. Almost like good used set of Darts or Worlds would be better quality. Sad with all the tech we have that quality has gone down. But everyone saved a few dollars, or did we? Guess maybe the jobs should have stayed in the USA.

Those seats sound like monel or something.

whats the turn around time on a set of heads?

Is it worth seeing how much power they make as is?

Early 2000 AFR 185s were not so friendly :)

Sounds like monel. It's hard and gummy at the same time

Shouldn't you do the vacuum test without the valve springs?

You dont have to spend 3000 on a ston setup.....1500 for the goodson driver is robbery.... ..with a mix of a good used driver and dresser, and some new stone holders and pilots u can do a good job

Or buy a Bridgeport for 5 grand and roll over fixture. Takes twice as long to indicate in the pilot

I thought Chinesium just made it harder to understand. Like Chinesium arithmetic. 😅

Eric, I know you are a Trick Flow dealer, what experience do you have with their products? I have a set of powerport 190 for small block mopar (still in box). This worries me. Thoughts?

It will fix itself as you drive, only takes 10,000 miles or so.

Wouldn't the harder seats, even though they're a bitch to cut, but wouldn't they last longer once done?

I’ve sold promaxx heads I’m not a fan there is a reason they are cheaper

I bet if you dynoed them as they are and then touch them with a stone to seal the factory valve job you would not see any difference in power. Everything on that head will move once it's torqued and the again at operating temperature. Temperature.

If you were actually shocked you really have not been paying attention to Yamaha product development. Poor Johnny Rae. Last to ride the R1 as a swan song. No more soup for you!

Never trust Edelbrock out of the box heads!! Get them checked before install!

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