Thanks for taking the time to show this to us viewers. I really enjoy to see all of the machining work that is done for the builds. Glad I found your channel.
There is still some variables not mentioned like quench, total seal gapless rings or standard, cam max lift to take advantage of the new heads airflow, other cam spec, are you using short travel lifters like Johnson's to take advantage of the 7000+ rpm's?...I'm going to say 642Hp and 563Ft.tq. that's a 105hp more which is doable with the new mods....Loving the details/video, Keep up the Awesome work!
Just wanna say that i am a huge cathedral port fan. Yes for a mild applications they make less peak power but low to mid torque is very instant and make for a nice drivable car! Did a ls3 cam n tune think a 232/236@112 cam, made 450rwhp and tuned a ls2 and myself and a few others praised its manners and all preferred the ls2 to its power delivery and smoothness! I will be doing first stroker soon and want to achieve fast airspeed into combustion chambers to achieve a lot of low down torque. Anyone who can give opinion to a 408 stroker to achieve a fast torque monster id like to hear!
I agree, the smaller CSA on cathedral port heads really promotes a lower rpm torque curve. For an all out racing application though like what I am doing, you just can’t beat the larger CSA in the rectangle port heads. It’s all application specific though!! Many variables to consider
@@JacobVillemain absolutely, horses for courses and courses for horses! Ive done a few engines and the dynos do do the cathedral port heads justice. I usually get a disappointing look when tell them the dyno reading. But a week or so later tell me how much they love it and they've blown this and that car away... What i am worried about is not seeing the mid range dyno results for a cathedral port on a stroker. Was this the case for yourself?
The mid range on my 402" was still very strong with the cathedral port heads. However with the 821s I anticipate I will pick up power & torque everywhere through-out the rpm curve.
Couple of questions from an old engine machinist. I sold my shop late 1980's and had a non compete clause in the contract, so I have never done any machine work on LS engines. Do you worry about intake manifold alignment dropping the "V" , milling so much off the head to deck surface? I understand the rocker assemblies are non adjustable on LS engines. How do you set valve lash ? Do you run shorter push rods, or do you add adjustable rockers to compensate for milling so much off the heads? I enjoy your channel. Take care.
Yes I will most likely need to mill the intake flanges so the ports line up correctly. Valve lash is set with pushrod length. Now-a-days you can get pushrods off the shelf in .025” increments. Thanks
Thank you for responding. Hydraulic lifters used to have .060 movement from no oil pressure to pumped up with the engine running with oil pressure, so you can get the lash set pretty close to mid throw with .025 of adjustment from the push rods. Interesting. I have one last question for you. When I had my shop, it was attached to a NAPA parts store. I know all the Allied Engine Parts part numbers for the parts I used to use to use to build small block Chevys. Unfortunately NAPA no longer sells engine parts according to my local NAPA parts store. I used to use valve stem seals that were attached to a flange that the valve spring would sit on so they couldn't pop off the top of the valve guides. Do you know if anyone makes those seals any more? The Perfect Circle tool I have leaves the valve guide boss .502 dia. Thank again for your help.
I’m fairly new subscriber. You really seem to know what your doing. I’m building a 5.3 .040 over for my boat. Hardest part is my cam because the manifold and risers prefer nothing over 226 duration @.50
@@sic7camaro Tight LSA cams are winning on N/A apps. Rich Holdener did a test of 108/112 and 120 LSA with rest of cam specs the same. The 112 LSA made 34 more ft-lb to 5500 then the torque curve and power was similar to the 120. The 108 LSA made 14 more ft-lb to 5500 than the 112 LSA, the torque curve matched until the final 300 rpm where the 108LSA made 7 more rwhp at the end of the curve. So the 108 LSA was worth almost 50 ft-lb over the 120 lsa up to 5500 and a little at the top.
My guess: If the car wanted to make more high rpm power, but was constrained by the heads, having the new heads will make a huge gain. If it's setup for moderate power under 7000 RPM, and a long runner intake then the heads won't make as much as you think they should. So on one combo they could make 30-50 HP and another they can release over 100 more HP. With the old combo making 537rwhp on 402 cubic inches, I'm guessing it's a long runner intake such as the fast or truck, and the cam is not that "big", probably 228-235@.05". Something that power peaks at 6500 RPM on the 6.0L and 6000 RPM on the 402 cubic inch 6.6L. So my guess is a 30-50HP release. With 100+ additional with bigger cam and intake setup for power peak in the 7000-8000 RPM range. So 575 rwhp with current combo, but enough head for closer to 700 HP at the wheels with the right supporting parts. I'm guessing the old cathedral ports made 290-310 CFM @.5".
I'd be curious to see you cc that head again you wouldn't think the depth of each cut has no hold on the cc being removed from the chamber because of its shape it narrows as you mill deeper so each additional.001 shrinks the chamber cc less then the previous
You said later on you were going to turbo that motor, are you going to turbo it at a 13 to 1 ratio. I know LSU's have a good combustion chamber ,but wouldn't that make tuning touchy
IMHO, Milling that much was a bad idea. A piston would have been a better option. BUT, I'm wondering how well this is going to work when a LS3 head needs a minimum of a 4.030 bore to for the valves to clear the cylinder wall. But best of luck
Do you have your own shop. This is the first time I seen your channel. I want to have something dependable and more powerful than my stock lm7 5.3. I have a 2000 Chevy Tahoe. Good power. I just wanted something a little more peppy and more powerful. I'm kinda interested in a turbo kit for it too. I need to buy a new engine so I'm considering my options at this time. I hear good things about the 6.0 not sure if I need a bigger engine as I wanted to not go too crazy . I need someone to build me a good motor N/A that can possibly handle boost in the future If I thought the N/A wasn't powerful enough.
If the car wanted to make more high rpm power, but was constrained by the heads, having the new heads will make a huge gain. If it's setup for moderate power under 7000 RPM, and a long runner intake then the heads won't make as much as you think they should. So on one combo they could make 30-50 HP and another they can release over 100 more HP. With the old combo making 537rwhp on 402 cubic inches, I'm guessing it's a long runner intake such as the fast or truck, and the cam is not that "big", probably 228-235@.05". Something that power peaks at 6500 RPM on the 6.0L and 6000 RPM on the 402 cubic inch 6.6L. So my guess is a 30-50HP release. With 100+ additional with bigger cam and intake setup for power peak in the 7000-8000 RPM range. So 575 rwhp with current combo, but enough head for closer to 700 HP at the wheels with the right supporting parts. I'm guessing the old cathedral ports made 290-310 CFM @.5".
How do you feel about the ported 243's on a 416 stroker as a street engine 6800 rpm and below? Still too big of a restriction to consider even if not racing? I'd like to build a stroker if my LS1 lets go.
Hi love your show I’m from Sydney Australia I’ve noticed you don’t degree the cams in on your engines neither do I & I build engines I’m not a machinist just an engine builder the once I did degree the cam in it ended up dot to dot Another thing those heads look good the CNC ported heads are they Speedmaster from here in Australia? I’m going to buy a set that’s all
A quick way if taking the guesswork out of finding your Z0 is using a .001 shim, and then subtracting the .001 in your offset. I'm sure you already knew that, but if you didn't, you might find that useful
@andrewwilliamson1879 the most compression you can run on 93 is around 11 to 1. It also depends on the valve opening events, LSA, and duration of the cam. More duration and overlap can allow more compression. Also you have to have to be careful of the ignition timing. Technology has brought us a long way with being able to run more compression. Direct injection helps also because it cools the cylinders a little more. A real good cooling system is a big help.Hope that helps.
Rad stuff. Whats the best way to inquire about getting an LS package done by you guys? The website only lists one engine option for the LS family. Thanks!
Is it worth it to bump up compression on an LSA application? I like the idea of higher compression with an lsa blower. Id be running 93 oct or E85 of course.
Thanks for taking the time to show this to us viewers. I really enjoy to see all of the machining work that is done for the builds. Glad I found your channel.
You are welcome!
Love the amount of info in your vids. Awesome channel 👍
.080” off the decks? Wow, will the intake ever line up?
💀 💀 💀
Obviously.
Lines up perfect for me
There is still some variables not mentioned like quench, total seal gapless rings or standard, cam max lift to take advantage of the new heads airflow, other cam spec, are you using short travel lifters like Johnson's to take advantage of the 7000+ rpm's?...I'm going to say 642Hp and 563Ft.tq. that's a 105hp more which is doable with the new mods....Loving the details/video, Keep up the Awesome work!
Jacob I want a set of those badass sonsabitches!!
Fulltiltboogie baby!!!!!
Just wanna say that i am a huge cathedral port fan. Yes for a mild applications they make less peak power but low to mid torque is very instant and make for a nice drivable car! Did a ls3 cam n tune think a 232/236@112 cam, made 450rwhp and tuned a ls2 and myself and a few others praised its manners and all preferred the ls2 to its power delivery and smoothness! I will be doing first stroker soon and want to achieve fast airspeed into combustion chambers to achieve a lot of low down torque. Anyone who can give opinion to a 408 stroker to achieve a fast torque monster id like to hear!
I agree, the smaller CSA on cathedral port heads really promotes a lower rpm torque curve. For an all out racing application though like what I am doing, you just can’t beat the larger CSA in the rectangle port heads. It’s all application specific though!! Many variables to consider
@@JacobVillemain absolutely, horses for courses and courses for horses!
Ive done a few engines and the dynos do do the cathedral port heads justice. I usually get a disappointing look when tell them the dyno reading. But a week or so later tell me how much they love it and they've blown this and that car away...
What i am worried about is not seeing the mid range dyno results for a cathedral port on a stroker.
Was this the case for yourself?
The mid range on my 402" was still very strong with the cathedral port heads. However with the 821s I anticipate I will pick up power & torque everywhere through-out the rpm curve.
@@JacobVillemain be great to see the back to back results.
Cheers!
@@JacobVillemain Hi did you get any results?
Couple of questions from an old engine machinist.
I sold my shop late 1980's and had a non compete clause in the contract, so I have never done any machine work on LS engines.
Do you worry about intake manifold alignment dropping the "V" , milling so much off the head to deck surface?
I understand the rocker assemblies are non adjustable on LS engines.
How do you set valve lash ? Do you run shorter push rods, or do you add adjustable rockers to compensate for milling so much off the heads?
I enjoy your channel. Take care.
Yes I will most likely need to mill the intake flanges so the ports line up correctly.
Valve lash is set with pushrod length. Now-a-days you can get pushrods off the shelf in .025” increments.
Thanks
Thank you for responding. Hydraulic lifters used to have .060 movement from no oil pressure to pumped up with the engine running with oil pressure, so you can get the lash set pretty close to mid throw with .025 of adjustment from the push rods. Interesting.
I have one last question for you.
When I had my shop, it was attached to a NAPA parts store.
I know all the Allied Engine Parts part numbers for the parts I used to use to use to build small block Chevys.
Unfortunately NAPA no longer sells engine parts according to my local NAPA parts store.
I used to use valve stem seals that were attached to a flange that the valve spring would sit on so they couldn't pop off the top of the valve guides.
Do you know if anyone makes those seals any more?
The Perfect Circle tool I have leaves the valve guide boss .502 dia.
Thank again for your help.
@@JacobVillemain how much did you end up having to mill the intake manifold to get it to align? If you don't mind me asking
Wish you had shown the deburring process
50 more cfm = 100 more hp plus .75 more compression an extra 15 to 20hp.. so an extra 120 hp
I’m fairly new subscriber. You really seem to know what your doing. I’m building a 5.3 .040 over for my boat. Hardest part is my cam because the manifold and risers prefer nothing over 226 duration @.50
Very excited to see this 👀 I’m working on getting some ls3 heads for mine too!
Yes!! Way gooder than cathedral port heads
How much to do my heads this way?
@@chevroletiroc we only sell the new heads outright
How much are they
@@chevroletiroc $2,495
great infomation thanks for sharing
i did mill ls3 heads about .043 in and i thought that was too much ... how u check piston to head clearance ? i got dome pistons too
those cathedral intake ports are great!!
Similar flowing cylinder head or better for a big black Chevy with a 4.6 cylinder bore
What’s the most you’ve milled ls3 heads down and not ram into intake fitting issues?😅
Did you tune it or had a tuner? I am curious what the timing was at WOT.
I'd like to know the LSA you had on the original cam. I bet it was way too wide. That would cost you Big HP and TQ
like your channel. I have a stock head LS3 corvette with A&A super making 725 RWHP. At what HP level do i need to do my heads.
When will this head be available to the public?
Nice 👍🏽
My 418 made 625rwhp on e85 12:8.1
Damn spicy unit. Cam specs and intake?
@@JacobVillemain fast 102 24x/25x 114+?
@@sic7camaro We like that. I hopefully should be in the same ball park with my 245/257 cam
Wow! Great numbers. What was WOT timing?
@@sic7camaro Tight LSA cams are winning on N/A apps. Rich Holdener did a test of 108/112 and 120 LSA with rest of cam specs the same.
The 112 LSA made 34 more ft-lb to 5500 then the torque curve and power was similar to the 120.
The 108 LSA made 14 more ft-lb to 5500 than the 112 LSA, the torque curve matched until the final 300 rpm where the 108LSA made 7 more rwhp at the end of the curve.
So the 108 LSA was worth almost 50 ft-lb over the 120 lsa up to 5500 and a little at the top.
when you milled the heads di you have any problem with mounting the intake
Did you run into any issues with the intake manifold not lining up?
How much for a set of heads like those
So I can buy these LS3 heads from you and it's a 100% bolt on to my LS2 Corvette block using an LS3 Intake manifold??
So you don’t need to seat the valves on newer vehicles?
Any intake alignment issues?
My guess: If the car wanted to make more high rpm power, but was constrained by the heads, having the new heads will make a huge gain. If it's setup for moderate power under 7000 RPM, and a long runner intake then the heads won't make as much as you think they should. So on one combo they could make 30-50 HP and another they can release over 100 more HP. With the old combo making 537rwhp on 402 cubic inches, I'm guessing it's a long runner intake such as the fast or truck, and the cam is not that "big", probably 228-235@.05". Something that power peaks at 6500 RPM on the 6.0L and 6000 RPM on the 402 cubic inch 6.6L. So my guess is a 30-50HP release. With 100+ additional with bigger cam and intake setup for power peak in the 7000-8000 RPM range. So 575 rwhp with current combo, but enough head for closer to 700 HP at the wheels with the right supporting parts. I'm guessing the old cathedral ports made 290-310 CFM @.5".
I'd be curious to see you cc that head again you wouldn't think the depth of each cut has no hold on the cc being removed from the chamber because of its shape it narrows as you mill deeper so each additional.001 shrinks the chamber cc less then the previous
Hiw much for tge heads
Hi do you sale heads an other parts for engines if you do can you give me pricing or a website to go to? Thank you for your time.
You said later on you were going to turbo that motor, are you going to turbo it at a 13 to 1 ratio. I know LSU's have a good combustion chamber ,but wouldn't that make tuning touchy
I haven’t decided yet. Part of me wants to try turboing it at 13.0:1 and see what happens 😂
If it proves to difficult to tune I will swap heads out
how much would cost to machine heads like yours if a customer dropped of a set of ls3 heads ?
We now have our own aftermarket castings made. We no longer machine or work with stock castings.
smedingperformance.com/collections/cylinder-heads
Just curious, how did you get to where your at knowledge wise? School, owner taught you, did you grow up around it? Thanks
Hands on experience and owner taught!
You’ll gain 90 hp. With your new combo
We’re this machine shop located
IMHO, Milling that much was a bad idea. A piston would have been a better option. BUT, I'm wondering how well this is going to work when a LS3 head needs a minimum of a 4.030 bore to for the valves to clear the cylinder wall. But best of luck
It worked amazing. Made 600whp & went 200+ at the TX Mile
Do you have your own shop. This is the first time I seen your channel. I want to have something dependable and more powerful than my stock lm7 5.3. I have a 2000 Chevy Tahoe. Good power. I just wanted something a little more peppy and more powerful. I'm kinda interested in a turbo kit for it too. I need to buy a new engine so I'm considering my options at this time. I hear good things about the 6.0 not sure if I need a bigger engine as I wanted to not go too crazy . I need someone to build me a good motor N/A that can possibly handle boost in the future If I thought the N/A wasn't powerful enough.
So what did it end up making for power? Working on the same build my self
590+ wheel! There is a video somewhere on the channel showing it
Are you running a solid roller or Hydraulic roller?
This combination was hydraulic!
What casting number are those LS3 heads?
823 or
821?
Thanks
821
Which cam was on this car? Which intake manifold?
If the car wanted to make more high rpm power, but was constrained by the heads, having the new heads will make a huge gain. If it's setup for moderate power under 7000 RPM, and a long runner intake then the heads won't make as much as you think they should. So on one combo they could make 30-50 HP and another they can release over 100 more HP. With the old combo making 537rwhp on 402 cubic inches, I'm guessing it's a long runner intake such as the fast or truck, and the cam is not that "big", probably 228-235@.05". Something that power peaks at 6500 RPM on the 6.0L and 6000 RPM on the 402 cubic inch 6.6L. So my guess is a 30-50HP release. With 100+ additional with bigger cam and intake setup for power peak in the 7000-8000 RPM range. So 575 rwhp with current combo, but enough head for closer to 700 HP at the wheels with the right supporting parts. I'm guessing the old cathedral ports made 290-310 CFM @.5".
How do you feel about the ported 243's on a 416 stroker as a street engine 6800 rpm and below? Still too big of a restriction to consider even if not racing? I'd like to build a stroker if my LS1 lets go.
243s will work well too
What is your website that we can order these heads from??
smedingperformance.com Currently sold out but more coming soon.
Hi love your show I’m from Sydney Australia I’ve noticed you don’t degree the cams in on your engines neither do I & I build engines I’m not a machinist just an engine builder the once I did degree the cam in it ended up dot to dot
Another thing those heads look good the CNC ported heads are they Speedmaster from here in Australia?
I’m going to buy a set that’s all
Forkin' first!!!!
You rock 😂
A quick way if taking the guesswork out of finding your Z0 is using a .001 shim, and then subtracting the .001 in your offset.
I'm sure you already knew that, but if you didn't, you might find that useful
What fuel will u be running? and didn't think u could cut that much off and not have PTV issues. Can't wait to see your end result and hp gains
340lph. I had almost .200” PTV clearance so this should be no problem.
@@JacobVillemain pump gas 93 ⛽?
Pump E85
How much compression have u been able to run on 93 pump gas before?
@andrewwilliamson1879 the most compression you can run on 93 is around 11 to 1. It also depends on the valve opening events, LSA, and duration of the cam. More duration and overlap can allow more compression. Also you have to have to be careful of the ignition timing. Technology has brought us a long way with being able to run more compression. Direct injection helps also because it cools the cylinders a little more. A real good cooling system is a big help.Hope that helps.
Dang! Living dangerously cleaning those ports up with a cumbersome electric die with no protection over the seats.
I like to live on the edge
624hp! I'll take a free smeding hat for being right!hahahaha
Ha!
@@JacobVillemain lol it would be a win win on both parts! Seriously though I am very anxious to see what you make power wise.
605.23 Horsepowers
I like it 😎
Rad stuff. Whats the best way to inquire about getting an LS package done by you guys? The website only lists one engine option for the LS family. Thanks!
Message me on Instagram!
@@JacobVillemain done! Thanks!
708hp at the wheels
610.7
680hp
600hp
Is it worth it to bump up compression on an LSA application? I like the idea of higher compression with an lsa blower. Id be running 93 oct or E85 of course.
653hp
+75hp
768 hp
599.8
Oof that would hurt!!
Maybe 30 horses 🐎 more
644.8 hp
780 hp
I'll say at least 55 hp.
564
America 🇺🇸 💪🏼🔧🔩🤙🏼
Change the title from "cnc machining LS3 heads for ricky" to "Video of myself talking about useless information"