[Z06] Ported LS7 Heads???
02-03-2009, 05:21 PM
#41
Melting Slicks
I'm going to generalize here and back it up with data sheets when I get time, which won't be until later in the week.
Intake Ports
Flow numbers on the the stock heads (using a radius plate) peak at .550 lift and ~350 CFM - by .600 lift they head south in a hurry and at .700 lift the turbulence is deafening. However, attach the stock intake manifold and even though the CFM drops by 30 points the curve becomes stable past .625 lift before dropping like a rock.
Our ported heads, same radius plate as above, peak past .650 lift ~390 CFM and with our ported intake attached carry ~375 plus CFM past .800 lift - no turbulence. Not much loss with a ported intake.
Those numbers are repeatable and given any free time this week I'll post a video of them on the flow bench. BTW, it's a combination of the CNC work and the valve work that contribute to the gains.
Exhaust Ports
Flow numbers on the the stock heads (using a 1 7/8" pipe) peak at .550 lift and ~245 CFM - by .600 lift the numbers start to fall and by .650 they are past being over.
Our ported heads, same pipe as above, peak past .650 lift ~280 CFM and carry that flow to .750 lift.
Summary & Notes
► Intake and exhaust ports can be substantially improved upon but the ultimate HP gains are a result of a "complete package" just not a single part. As an example: The right cam, adjusted DCR and an intake system capable of evacuating the manifold will show huge gains while a less than optimized package will fail.
► Gains in CFM are a result in both porting work and valve & valve seat work.
► For comparison -peak CFM numbers alone are no more relevent than only peak HP numbers - Area under the curve is the king and our CFM gains are across the board, verified by independent shops like WCCH.
► All test information derived from our standard SF600 bench
Intake Ports
Flow numbers on the the stock heads (using a radius plate) peak at .550 lift and ~350 CFM - by .600 lift they head south in a hurry and at .700 lift the turbulence is deafening. However, attach the stock intake manifold and even though the CFM drops by 30 points the curve becomes stable past .625 lift before dropping like a rock.
Our ported heads, same radius plate as above, peak past .650 lift ~390 CFM and with our ported intake attached carry ~375 plus CFM past .800 lift - no turbulence. Not much loss with a ported intake.
Those numbers are repeatable and given any free time this week I'll post a video of them on the flow bench. BTW, it's a combination of the CNC work and the valve work that contribute to the gains.
Exhaust Ports
Flow numbers on the the stock heads (using a 1 7/8" pipe) peak at .550 lift and ~245 CFM - by .600 lift the numbers start to fall and by .650 they are past being over.
Our ported heads, same pipe as above, peak past .650 lift ~280 CFM and carry that flow to .750 lift.
Summary & Notes
► Intake and exhaust ports can be substantially improved upon but the ultimate HP gains are a result of a "complete package" just not a single part. As an example: The right cam, adjusted DCR and an intake system capable of evacuating the manifold will show huge gains while a less than optimized package will fail.
► Gains in CFM are a result in both porting work and valve & valve seat work.
► For comparison -peak CFM numbers alone are no more relevent than only peak HP numbers - Area under the curve is the king and our CFM gains are across the board, verified by independent shops like WCCH.
► All test information derived from our standard SF600 bench
02-03-2009, 11:26 PM
#42
Melting Slicks
Thread Starter
So there ya have it vendors you have me willing to be the guinea pig. I milled and gained 33rwhp, with a set of stock LS7 heads. I have offered to remove, send, and dyno a set of ported heads by any vendor who has the faith in their product. If and I mean IF I gain even 25 rwhp over what I made with just the milling Im willing too pay you double and you have a guy willing to buy a set. Not only that but Im willing to post up the unbiased dyno results both good an bad. I will be doing the tests after the tunes are perfect. In an economy such as this you would think this would be a sweet deal, that is unless the smoke and mirrors are just that they seem. Nothing but BS 
02-04-2009, 01:09 AM
#43
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Maybe you'll have more takers if you offered to:
Pay 2X the price to a vendor upfront, then if they make 25rwhp they keep everything you've paid and if it doesn't then they refund you 1/2 the money.
I don't think any potential headwork purchasers would go for that one but it's essentially the reverse of what you're asking of the vendors. I just don't think it's quite fair to 'call out' the vendors in this way. From a business standpoint it just doesn't make good financial sense; even if they are confident in their product. I'm not calling anyone a cheat or liar, but to spend your time to port a set of heads for potentially no payment? In even the worse economy, I think everyone would rather sit around, do nothing and go bankrupt than do work for free, not get paid and go bankrupt.
As for cylinder heads, maybe someone would like to try a set of LS7 as cast heads vs. the CNC'd heads. That would be an interesting comparison.
Bandit, you made 33rwhp going from 11.0 up to 12.26? On Pump? Nice.
Pay 2X the price to a vendor upfront, then if they make 25rwhp they keep everything you've paid and if it doesn't then they refund you 1/2 the money.
I don't think any potential headwork purchasers would go for that one but it's essentially the reverse of what you're asking of the vendors. I just don't think it's quite fair to 'call out' the vendors in this way. From a business standpoint it just doesn't make good financial sense; even if they are confident in their product. I'm not calling anyone a cheat or liar, but to spend your time to port a set of heads for potentially no payment? In even the worse economy, I think everyone would rather sit around, do nothing and go bankrupt than do work for free, not get paid and go bankrupt.
As for cylinder heads, maybe someone would like to try a set of LS7 as cast heads vs. the CNC'd heads. That would be an interesting comparison.
Bandit, you made 33rwhp going from 11.0 up to 12.26? On Pump? Nice.
02-04-2009, 01:42 AM
#44
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Now why would I offer 2X the money upfront and if it works they keep it and if not they send me half back. I would be a complete idiot!!!! If I were to do it that way then I would just pay the normal price to have them ported and report the findings. I have already shown its the milling that gets the extra power and that the porting gets very and I mean VERY minimal gains at best. I simply put up the offer cause while it does take some time to port a set of heads, it is only time that it costs to port a set of heads, so if a vendor did it he would not really be out any money if he were to do them on the side. But the vendor has the chance to prove his claims and acually not only sell a set of heads but egt paid twice for the heads he took the chance to prove his claims on. Everyones time is worth something I understand that but that also includes our time as the customers.
Now lets flip the coin here, is it fair for the "Vendors" to claim a 35 rwhp gain from porting the heads and charging over a 1000 for a port cleanup that essentially does nada and mill them which is where the power is coming from. When they could be straight up with us and say hey we will mill the heads and charge u 150.00 and we will still see pretty much the whole 30+ rwhp gain?? No, why because they cant charge over a 1000 for milling the heads.
Please dont start saying its not fair cause its also not fair to you, me, and every other consumer to be sold a bunch of smoke and mirrors either. If I told you on this table is a stock set of heads milled to 12 to 1 that will gain you 30+ rwhp and keep all the low lift flow velocity and I will charge you 150.00 for this. On the other table I have a set of the same heads same CR but we also ported them and you "Should" see 35 rwhp but I want 1200+ for them. Please tell me what set of heads you are gunna take???? All I want to show my fellow car lovers that there is no reason to get a set of ported heads when they arent going to get u but a few more horses over just milling what you have.
Now lets flip the coin here, is it fair for the "Vendors" to claim a 35 rwhp gain from porting the heads and charging over a 1000 for a port cleanup that essentially does nada and mill them which is where the power is coming from. When they could be straight up with us and say hey we will mill the heads and charge u 150.00 and we will still see pretty much the whole 30+ rwhp gain?? No, why because they cant charge over a 1000 for milling the heads.
Please dont start saying its not fair cause its also not fair to you, me, and every other consumer to be sold a bunch of smoke and mirrors either. If I told you on this table is a stock set of heads milled to 12 to 1 that will gain you 30+ rwhp and keep all the low lift flow velocity and I will charge you 150.00 for this. On the other table I have a set of the same heads same CR but we also ported them and you "Should" see 35 rwhp but I want 1200+ for them. Please tell me what set of heads you are gunna take???? All I want to show my fellow car lovers that there is no reason to get a set of ported heads when they arent going to get u but a few more horses over just milling what you have.
02-04-2009, 02:23 AM
#45
Supporting Vendor
Chris I do understand where you are coming from. There is a lot of money tied up in head developement. I can tell you that a LOT!! of what we have tested is what you are talking about. MTI is so far the head that I found the gains with. I test so I can sell something that works. Since this thread has started I WILL test a set of stock heads with milling only...Very soon. BTW the vendors may not want to send you heads because they still waiting on that big cam dyno thrash you have been talking about for the past year. No one wants to wait that long with the heads(LOL).
02-04-2009, 02:29 AM
#46
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For exactly the same reason's you feel that you would be an idiot for doing that, I can't imagine any vendor stepping up to the plate on your offer of paying them double if it makes the power. My point however wasn't to say that it's right for vendors to make claims that really don't exist. It's not exactly right for people to publically call out the vendors with a (potentially) financially unsound offer either. Let's just say I have a product that I know will make the power, I'm not going to send it over to you for free in hopes that you'll pay me double. And since I don't, a potential customer may start to believe that I have something to hide? 
You might say that the claims made by the vendor can't be trusted because they have a vested interest (selling their product) but if someone were to step up and port your heads that you get for free or pay 2x, then you would automatically have a vested interest as well(getting free product). Afterall, it's not hard to fool the dyno. So in the end, if you really want to prove your point the only way to do it is as you said, buy a set and just test them. Personally, I appreciate everyone, including you, that takes time (and money) to put out honest reviews of products. Ultimately the honest vendors are the ones that are sucessful in the long run.
As for which heads I'd choose it would depend on what I'm trying to build. The less expensive set is better hp/$ value but if you're trying to get that last 5hp, then you have to go with the ones that give you 5 extra hp. You and I both know those last 5hp don't come cheap.
So back to cylinder head discussions, how much power do you think the factory CNC jobs make over an as cast head? With the same decks obviously.
You might say that the claims made by the vendor can't be trusted because they have a vested interest (selling their product) but if someone were to step up and port your heads that you get for free or pay 2x, then you would automatically have a vested interest as well(getting free product). Afterall, it's not hard to fool the dyno. So in the end, if you really want to prove your point the only way to do it is as you said, buy a set and just test them. Personally, I appreciate everyone, including you, that takes time (and money) to put out honest reviews of products. Ultimately the honest vendors are the ones that are sucessful in the long run.
As for which heads I'd choose it would depend on what I'm trying to build. The less expensive set is better hp/$ value but if you're trying to get that last 5hp, then you have to go with the ones that give you 5 extra hp. You and I both know those last 5hp don't come cheap.
So back to cylinder head discussions, how much power do you think the factory CNC jobs make over an as cast head? With the same decks obviously.
Now why would I offer 2X the money upfront and if it works they keep it and if not they send me half back. I would be a complete idiot!!!! If I were to do it that way then I would just pay the normal price to have them ported and report the findings. I have already shown its the milling that gets the extra power and that the porting gets very and I mean VERY minimal gains at best. I simply put up the offer cause while it does take some time to port a set of heads, it is only time that it costs to port a set of heads, so if a vendor did it he would not really be out any money if he were to do them on the side. But the vendor has the chance to prove his claims and acually not only sell a set of heads but egt paid twice for the heads he took the chance to prove his claims on. Everyones time is worth something I understand that but that also includes our time as the customers.
Now lets flip the coin here, is it fair for the "Vendors" to claim a 35 rwhp gain from porting the heads and charging over a 1000 for a port cleanup that essentially does nada and mill them which is where the power is coming from. When they could be straight up with us and say hey we will mill the heads and charge u 150.00 and we will still see pretty much the whole 30+ rwhp gain?? No, why because they cant charge over a 1000 for milling the heads.
Please dont start saying its not fair cause its also not fair to you, me, and every other consumer to be sold a bunch of smoke and mirrors either. If I told you on this table is a stock set of heads milled to 12 to 1 that will gain you 30+ rwhp and keep all the low lift flow velocity and I will charge you 150.00 for this. On the other table I have a set of the same heads same CR but we also ported them and you "Should" see 35 rwhp but I want 1200+ for them. Please tell me what set of heads you are gunna take???? All I want to show my fellow car lovers that there is no reason to get a set of ported heads when they arent going to get u but a few more horses over just milling what you have.
Now lets flip the coin here, is it fair for the "Vendors" to claim a 35 rwhp gain from porting the heads and charging over a 1000 for a port cleanup that essentially does nada and mill them which is where the power is coming from. When they could be straight up with us and say hey we will mill the heads and charge u 150.00 and we will still see pretty much the whole 30+ rwhp gain?? No, why because they cant charge over a 1000 for milling the heads.
Please dont start saying its not fair cause its also not fair to you, me, and every other consumer to be sold a bunch of smoke and mirrors either. If I told you on this table is a stock set of heads milled to 12 to 1 that will gain you 30+ rwhp and keep all the low lift flow velocity and I will charge you 150.00 for this. On the other table I have a set of the same heads same CR but we also ported them and you "Should" see 35 rwhp but I want 1200+ for them. Please tell me what set of heads you are gunna take???? All I want to show my fellow car lovers that there is no reason to get a set of ported heads when they arent going to get u but a few more horses over just milling what you have.
02-04-2009, 02:39 AM
#47
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Chris I do understand where you are coming from. There is a lot of money tied up in head developement. I can tell you that a LOT!! of what we have tested is what you are talking about. MTI is so far the head that I found the gains with. I test so I can sell something that works. Since this thread has started I WILL test a set of stock heads with milling only...Very soon. BTW the vendors may not want to send you heads because they still waiting on that big cam dyno thrash you have been talking about for the past year. No one wants to wait that long with the heads(LOL).
02-04-2009, 02:48 AM
#48
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For exactly the same reason's you feel that you would be an idiot for doing that, I can't imagine any vendor stepping up to the plate on your offer of paying them double if it makes the power. My point however wasn't to say that it's right for vendors to make claims that really don't exist. It's not exactly right for people to publically call out the vendors with a (potentially) financially unsound offer either. Let's just say I have a product that I know will make the power, I'm not going to send it over to you for free in hopes that you'll pay me double. And since I don't, a potential customer may start to believe that I have something to hide?
You might say that the claims made by the vendor can't be trusted because they have a vested interest (selling their product) but if someone were to step up and port your heads that you get for free or pay 2x, then you would automatically have a vested interest as well(getting free product). Afterall, it's not hard to fool the dyno. So in the end, if you really want to prove your point the only way to do it is as you said, buy a set and just test them. Personally, I appreciate everyone, including you, that takes time (and money) to put out honest reviews of products. Ultimately the honest vendors are the ones that are sucessful in the long run.
As for which heads I'd choose it would depend on what I'm trying to build. The less expensive set is better hp/$ value but if you're trying to get that last 5hp, then you have to go with the ones that give you 5 extra hp. You and I both know those last 5hp don't come cheap.
So back to cylinder head discussions, how much power do you think the factory CNC jobs make over an as cast head? With the same decks obviously.
You might say that the claims made by the vendor can't be trusted because they have a vested interest (selling their product) but if someone were to step up and port your heads that you get for free or pay 2x, then you would automatically have a vested interest as well(getting free product). Afterall, it's not hard to fool the dyno. So in the end, if you really want to prove your point the only way to do it is as you said, buy a set and just test them. Personally, I appreciate everyone, including you, that takes time (and money) to put out honest reviews of products. Ultimately the honest vendors are the ones that are sucessful in the long run.
As for which heads I'd choose it would depend on what I'm trying to build. The less expensive set is better hp/$ value but if you're trying to get that last 5hp, then you have to go with the ones that give you 5 extra hp. You and I both know those last 5hp don't come cheap.
So back to cylinder head discussions, how much power do you think the factory CNC jobs make over an as cast head? With the same decks obviously.
I have the money to have my heads ported and when I get them ported it will be by none other than Mike Chapman. If anyone knows how to improve the LS7 it would be the developer of the LS7 head. I dont want a free port job but stop making the claim that something works that doesnt. If you want to prove me wrong then by all means show us yourselves what porting alone with no change to head chamber will do on the dyno. I WANT to see a gain from porting cause then I have not gotten to the last of the mods I can do to my engine. If porting will gain me a substantial amount, I would be the first to go out right now at 1 am and start removing my heads so that I could send them off. Me willing to do this is an unbiased test I cant fool the dyno its got a weather tower and does all its own calcs its a Dynojet. I am not saying that any vendor would be smart to take my offer cause they would LOSE. I am saying tell it how it is we port AND mill your heads for a gain of around 35rwhp. Shawn so far has been the only one to say yes the heads are milled and ported and he said this long before this thread started. AN just so you know by not stepping up to either take me up on the challenge or to do the test of porting gains by itself DOES show you have something your not telling. Katech has said here and many times they have seen very little gains from porting hence why they dont do it.
02-04-2009, 08:23 AM
#50
Supporting Vendor
Now listen you ya turd I tried to do the thrash and I tested all the cams I had an posted up my results. In the end it was the striker that make the most power you need to go look in some of my past posts. I did the tests and I posted up the results, striker by 15 peak over all others. Hence why I praise it! Not only that but alot of the people that said they would let me do their cams for some unknown reason didnt want to send it after all. SO BITE ME!!!!! I have already posted up the results from milling alone we want to see what porting ALONE zero milling done to the head!
That STRIKER is a Bad AZZ Cam. DO you have any idle video of the cam. I get several people asking for one?
02-04-2009, 11:20 AM
#51
Former Vendor
Bandit,
I was leaning towards giving you a set of heads but this post makes me question any that. You appear to have your mind made up that:
1) There are no grounds to port the heads
2) Porters/vendors, such as myself, are either falsifying results or outright lying
3) Only certain people know anything
As for milling heads - well of course milling the heads makes good more power and when a large cam "bleeds off" compression, DCR drops and milling the heads is a mandatory step just to get back to square one.
Bring your car to my shop and let's do a test.
1) Dyno car
2) Pull heads and flow test them
3) Flow test them with the manifold
4) CNC the heads
5) Redo all flow tests
6) tune and measure the gains
If the car does not pick up 1 RWHP for each CFM gain, no charge for the head work.
If the car does pick up, you pay me full tilt.
Also, please send the core for the intake - as I have stated a month ago - the core you sent me is not usable - it was ported by a hack and can not be salvaged. BTW, isn't this the very reason for the head test and by itself should be reported to the buying public?
Charlie
I was leaning towards giving you a set of heads but this post makes me question any that. You appear to have your mind made up that:
1) There are no grounds to port the heads
2) Porters/vendors, such as myself, are either falsifying results or outright lying
3) Only certain people know anything
As for milling heads - well of course milling the heads makes good more power and when a large cam "bleeds off" compression, DCR drops and milling the heads is a mandatory step just to get back to square one.
Bring your car to my shop and let's do a test.
1) Dyno car
2) Pull heads and flow test them
3) Flow test them with the manifold
4) CNC the heads
5) Redo all flow tests
6) tune and measure the gains
If the car does not pick up 1 RWHP for each CFM gain, no charge for the head work.
If the car does pick up, you pay me full tilt.
Also, please send the core for the intake - as I have stated a month ago - the core you sent me is not usable - it was ported by a hack and can not be salvaged. BTW, isn't this the very reason for the head test and by itself should be reported to the buying public?
Charlie
I have the money to have my heads ported and when I get them ported it will be by none other than Mike Chapman. If anyone knows how to improve the LS7 it would be the developer of the LS7 head. I dont want a free port job but stop making the claim that something works that doesnt. If you want to prove me wrong then by all means show us yourselves what porting alone with no change to head chamber will do on the dyno. I WANT to see a gain from porting cause then I have not gotten to the last of the mods I can do to my engine. If porting will gain me a substantial amount, I would be the first to go out right now at 1 am and start removing my heads so that I could send them off. Me willing to do this is an unbiased test I cant fool the dyno its got a weather tower and does all its own calcs its a Dynojet. I am not saying that any vendor would be smart to take my offer cause they would LOSE. I am saying tell it how it is we port AND mill your heads for a gain of around 35rwhp. Shawn so far has been the only one to say yes the heads are milled and ported and he said this long before this thread started. AN just so you know by not stepping up to either take me up on the challenge or to do the test of porting gains by itself DOES show you have something your not telling. Katech has said here and many times they have seen very little gains from porting hence why they dont do it.
02-04-2009, 11:30 AM
#52
Former Vendor
02-04-2009, 11:47 AM
#53
Le Mans Master
Bring your car to my shop and let's do a test.
1) Dyno car
2) Pull heads and flow test them
3) Flow test them with the manifold
4) CNC the heads
5) Redo all flow tests
6) tune and measure the gains
If the car does not pick up 1 RWHP for each CFM gain, no charge for the head work.
If the car does pick up, you pay me full tilt.
Charlie
02-04-2009, 12:45 PM
#54
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Shawn yes I have a idle clip and I will get it and send it to you it idles great nice sounding at 875 but I prefer it to be 925
I am willing to do that Charles Im not to far away from Cali Lets set it up Im game. An charles if you go back through my posts you will see that I stated so far only you have stood behind what you say is gained and I gained almost that exact amount. But there are those that do falsify their results in the hopes to outsell the competition.
I am willing to do that Charles Im not to far away from Cali
Lets set it up Im game. An charles if you go back through my posts you will see that I stated so far only you have stood behind what you say is gained and I gained almost that exact amount. But there are those that do falsify their results in the hopes to outsell the competition.
02-04-2009, 01:03 PM
#56
Safety Car
Just out of curiousity... What's the DCR of a stock LS7, and what's a general ballpark for the DCR of an LS7 with milled heads and a decently large cam? I know the cam really defines the exact DCR, but a general estimate would be handy. I tried calculating it, but I think I may have done something wrong because I was ending up with a DCR around 10.5 with milled heads and my QM600. That just seemed high.
02-04-2009, 01:12 PM
#58
Le Mans Master
and taking a guess at the specs of the Qm600, a car with stock heads and QM600 would probably be around a 8.1 DCR
once again, i hope someone corrects me if i'm way off
once again, i hope someone corrects me if i'm way off