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Re: Extruded Honed?
Originally Posted by BADKACHINA
If you took your air compressor and put an attachment to blow air (the kind with the handle and the changeable fittings), held the trigger open and drained your full air compressor would it take longer than if you took a knife and cut the end off the hose completely? If it does wouldn't that be because through the attachment there is more restriction thus allowing less air to pass through it as opposed to the hose being wide open with absolutely no restriction at all?
I'm just asking because it would make sense to me that in a blower application with a manifold designed for 420 hp you would think the blower could be capable of making more hp than the manifold is capable of no matter how much you increased the pressure. I'm just telling you what AZSM and another builder advised me. They both said that the stock manifold would be the most restrictive part of the entire engine after I changed the heads. The heads, the headers, the the blower are all capable of more hp than that stock manifold can handle. Thus back to my earlier post regarding putting a 500cmf carb on a 800 hp motor. It cannot create the hp with that carb even if it's under procharger carburetor assembly and you were forcing air through it. |
Re: Extruded Honed?
Originally Posted by Nordicflame
Smitty,
What cam are you running. Just curious. I think we're set up pretty similar. Thanks, Dave |
Re: Extruded Honed?
3 Attachment(s)
Here is a comparison pic of a stock manifold vs the modified ones,looks like azsm shortens the runners substantially. You get a idea of how blunt and fat the stock intake port dividers actually are,Smitty
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Re: Extruded Honed?
Re: Air hose example - less restriction and same pressure means more flow always, but intakes aren't the same as a hose or pipe. I am not an intake specialist but here's what I understand (I think).
The long runners are tuned to specific rpm. When the intake valve shuts it sends a pressure pulse back to the top of the runner where it reflects and returns to the valve at just the right time to help fill the cylinder. This acoustic supercharging effect is only "perfect" at one RPM. So if you are making cam, cylinder head and header changes that favour a higher RPM, the longer runners do become a liability, that's why people are cutting them down. The shorter the runner the higher the RPM at which the reflected pulse arrives at the intake valve at the right time. That's why I said I believe it when people say the long runners run out of steam at higher RPM. But that's different than saying they are restrictive. If you intend to keep the same cam timing and run the engine in the same RPM range, the long runner intake is not a bottleneck. An HP500EFI makes 500 HP at 5200 RPM. With the same cam and heads we can make 800 HP at 5500 RPM with relatively low boost. We haven't increased the volumetric efficiency of the engine much (maybe a little as noted above). What we have done is increase the density of every CFM that enters that engine. Looking at the torque curve I can't say that the intake is holding us back if 5500 RPM is the maximum we want to turn. If you want more power then change to a single plane intake, port the heads, and run a bigger cam. That engine will make 1000 HP. Dean Nickerson does exactly that using a 750 carb in one of our supercooler boxes. But he's spinning the engine at 6000+ RPM and 9 psi boost. Good questions though, makes you think. |
Re: Extruded Honed?
Tomcat you seem pretty knowlegable on the subject. I have absolutely no experience on the subject. I hope I've made some good decisions. Only time will tell.
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Re: Extruded Honed?
this discussion is taking on the overtones of the zealots vs the converts and it would take an encyclopedia of ground rules to define the terms so everyone was talking about the same thing.... so there isn't likely to be a consensus... and i have to tell you that the weath of experience and knowledge is really impressive... but there is one thing or two that i would reach into my pocket and bet cash green yankee dollars on... and that would be that no one is taking a box stock 502 and milling around inside the intake manifold making ZERO other changes and bolting it back on and making another 30 hp while keeping the area under the curve the same...
no one we are not talking about some street 305 out of a chevelle that chevy made the cheapest manifold they could for... we are talking about a purpose built factory hot rod motor built from good parts by smart people with access to the best cnc equipment money can buy. if this magic manifold that would buy 8 % with no other change existed, merc would have had one, programmed it into their cnc and every new motor from that day on would have it and the advertising blitz would blind you. i mean REALLY .... for the sake of 25 bucks worth of machine time an OEM MANUFACTURER can get an 8 % power increase ???? and they just say ... " oh the hell with it... well just let that go...." ??? not very likely and frankly if this magic manifold existed then the guys that do it would have a cnc set up making them day and night to satisfy the demand... sorry .... me and the easter bunny are going to have another beer. |
Re: Extruded Honed?
Originally Posted by stevesxm
this discussion is taking on the overtones of the zealots vs the converts and it would take an encyclopedia of ground rules to define the terms so everyone was talking about the same thing.... so there isn't likely to be a consensus... and i have to tell you that the weath of experience and knowledge is really impressive... but there is one thing or two that i would reach into my pocket and bet cash green yankee dollars on... and that would be that no one is taking a box stock 502 and milling around inside the intake manifold making ZERO other changes and bolting it back on and making another 30 hp while keeping the area under the curve the same...
no one we are not talking about some street 305 out of a chevelle that chevy made the cheapest manifold they could for... we are talking about a purpose built factory hot rod motor built from good parts by smart people with access to the best cnc equipment money can buy. if this magic manifold that would buy 8 % with no other change existed, merc would have had one, programmed it into their cnc and every new motor from that day on would have it and the advertising blitz would blind you. i mean REALLY .... for the sake of 25 bucks worth of machine time an OEM MANUFACTURER can get an 8 % power increase ???? and they just say ... " oh the hell with it... well just let that go...." ??? not very likely and frankly if this magic manifold existed then the guys that do it would have a cnc set up making them day and night to satisfy the demand... sorry .... me and the easter bunny are going to have another beer. You may very well be correct. It would be interesting for someone to actually dyno it outside of AZSM's facility. Here's just one more thought, if it did add 30hp bringing the total on the 502mpi to 550 hp and the 500hp at 475hp, wouldn't it be hard to sell the 500 for the extra money? Especially with only 25hp difference. There are other reasons that the motors fall into certain hp catagories. Not to say that Merc couldn't figure out a way to make 450 hp out of th 454mag, 475 hp out of the 502mag, and 500hp out of the 500hp. They have to entice you to up your purchase and justify the cost differences between motors. There may be hidden hp in some of those motors. I'll be willing to bet if the new 600 can run at 600hp at any temp or altitude it may be capable of 650 or 675, there may be a "magic" key to unlock this hidden hp in the future. Here's some more food for thought, Do you own a newer desiel truck? Plug in a programmer and watch how you will "magically" gain mileage and hp at the same time. I've experienced this myself and it really does work. No motor mods, no new parts, just tire burning power and better fuel economy. I actually gained 5mpg by adding a Bullydog tuner to my Powerstroke. So sometimes the Easter Bunny does comes through. ;) |
Re: Extruded Honed?
Me, I want a Fram Air Hog for Christmas, the way they peel out...gotta be worth 30 HP. :rolleyes:
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Re: Extruded Honed?
Originally Posted by stevesxm
this discussion is taking on the overtones of the zealots vs the converts and it would take an encyclopedia of ground rules to define the terms so everyone was talking about the same thing.... so there isn't likely to be a consensus... and i have to tell you that the weath of experience and knowledge is really impressive... but there is one thing or two that i would reach into my pocket and bet cash green yankee dollars on... and that would be that no one is taking a box stock 502 and milling around inside the intake manifold making ZERO other changes and bolting it back on and making another 30 hp while keeping the area under the curve the same...
no one we are not talking about some street 305 out of a chevelle that chevy made the cheapest manifold they could for... we are talking about a purpose built factory hot rod motor built from good parts by smart people with access to the best cnc equipment money can buy. if this magic manifold that would buy 8 % with no other change existed, merc would have had one, programmed it into their cnc and every new motor from that day on would have it and the advertising blitz would blind you. i mean REALLY .... for the sake of 25 bucks worth of machine time an OEM MANUFACTURER can get an 8 % power increase ???? and they just say ... " oh the hell with it... well just let that go...." ??? not very likely and frankly if this magic manifold existed then the guys that do it would have a cnc set up making them day and night to satisfy the demand... sorry .... me and the easter bunny are going to have another beer. |
Re: Extruded Honed?
and therein lay the logic trap..... your point about your truck exactly correct... i had a for f350 superduty that went alongside my buddies... he did the same things ( essentially you did) and got ok results.... not sure 5mpg but either way...positive results.... but the truck would then no long pass a state inspection for emmissions .... and therin lay the answer...
for street vehicles the mfg give up power all the time to operate within state and federal regulations, cafe standards and christ knows what else.... not the case here. merc could and would do what is economically and reasonabbly feasable to build performance... period. no emissions...no noise, no restrictions of any type.... just build a good solid hi performance motor for the general market... and at 415 or 425 or whatever it is , it is exactly that...EXACTLY why i bought them... but i have to tell you that there are some magic numbers in the consumer base and also in the structural arena.... and in a structural sense, 415/425 vs 450ish is no difference at all but in the CONSUMER market 450/500 is a magic number i maintain that if it was as simple as suggested that it would be insane for them not to be doing it... it is a complete no brainer for them.... 8 % more power for 25 bucks worth of machine time ... are you kidding me ? they would be on that like .... like..... well fur on the easter bunny. remember those commercials.... " we drained ALL the oil out of this car and drove it cross country with better milage and no fuel at all " this is the same deal. |
Re: Extruded Honed?
[QUOTE=tomcat]If you want more power then change to a single plane intake, port the heads, and run a bigger cam. That engine will make 1000 HP. Dean Nickerson does exactly that using a 750 carb in one of our supercooler boxes. But he's spinning the engine at 6000+ RPM and 9 psi boost.
QUOTE] As always Tom...A good answer :drink: That's actually what I meant in my prior post when I wrote "you mean like this" :evilb: Smitty, sounds very similar to the cam I'm running 236/244 112 .610/.632 and we all know what that is :rolleyes: Guess it has it's rep for a reason :evilb: Dave |
Re: Extruded Honed?
Originally Posted by stevesxm
and therein lay the logic trap..... your point about your truck exactly correct... i had a for f350 superduty that went alongside my buddies... he did the same things ( essentially you did) and got ok results.... not sure 5mpg but either way...positive results.... but the truck would then no long pass a state inspection for emmissions .... and therin lay the answer...
for street vehicles the mfg give up power all the time to operate within state and federal regulations, cafe standards and christ knows what else.... not the case here. merc could and would do what is economically and reasonabbly feasable to build performance... period. no emissions...no noise, no restrictions of any type.... just build a good solid hi performance motor for the general market... and at 415 or 425 or whatever it is , it is exactly that...EXACTLY why i bought them... but i have to tell you that there are some magic numbers in the consumer base and also in the structural arena.... and in a structural sense, 415/425 vs 450ish is no difference at all but in the CONSUMER market 450/500 is a magic number i maintain that if it was as simple as suggested that it would be insane for them not to be doing it... it is a complete no brainer for them.... 8 % more power for 25 bucks worth of machine time ... are you kidding me ? they would be on that like .... like..... well fur on the easter bunny. remember those commercials.... " we drained ALL the oil out of this car and drove it cross country with better milage and no fuel at all " this is the same deal. I agree, and I doubt on a stock motor there would any noticable gains. On the Mercury hp numbers I don't agree. I beleive that they purposely keep the numbers of the black motors at a certain level so as to not compete with their blue motors. Just an opinion, so in my opinion if they could make an easy 8% gain in hp it would be more detramental to them than beneficial. The hp 500's were only rated at 475hp. At a cost increase of 8 or 10k, plus they came with xz and xr drives who would pay the difference? How would they push the more expensive drives if they had a black motor with 450 hp and a standard drive? Could they justify buying and XZ for 25 more hp? Basically they could have thrown a bigger cam in the 502mag for almost no extra cost and made that 25hp easy. It already comes with a forged crank, 4 bolt main, rec. port heads, and plently of good parts more than capable of handling another 25hp. The stock cams in those motors are tiny, and they are tiny to restrict the hp numbers. |
Re: Extruded Honed?
Originally Posted by BADKACHINA
I agree, and I doubt on a stock motor there would any noticable gains.
On the Mercury hp numbers I don't agree. I beleive that they purposely keep the numbers of the black motors at a certain level so as to not compete with their blue motors. Just an opinion, so in my opinion if they could make an easy 8% gain in hp it would be more detramental to them than beneficial. The hp 500's were only rated at 475hp. At a cost increase of 8 or 10k, plus they came with xz and xr drives who would pay the difference? How would they push the more expensive drives if they had a black motor with 450 hp and a standard drive? Could they justify buying and XZ for 25 more hp? Basically they could have thrown a bigger cam in the 502mag for almost no extra cost and made that 25hp easy. It already comes with a forged crank, 4 bolt main, rec. port heads, and plently of good parts more than capable of handling another 25hp. The stock cams in those motors are tiny, and they are tiny to restrict the hp numbers. Merc designed these engines to be used in a large variety of applications from Fishing boats to Cruisers to Runabouts to Sport boats. High performance is only a small piece of the pie and that is where Merc. Racing come in to play. Do you think a fellow with a 40' Searay would except overhauling his engines at 250 or even 500hours? The black engines are designed with mild cams for longevity, 1000 or even 2000 hours. Only us speed crazy boaters don't mind pulling and engine to rebuild it every 2-3years. Hell, I think that is a big part of the hobby for a lot of us... :drink: |
Re: Extruded Honed?
outside my area of expertise and experience but sounds well reasoned and exactly correct....
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Re: Extruded Honed?
Originally Posted by Pat McPherson
Oh, I think you've got this one all wrong... :rolleyes:
Merc designed these engines to be used in a large variety of applications from Fishing boats to Cruisers to Runabouts to Sport boats. High performance is only a small piece of the pie and that is where Merc. Racing come in to play. Do you think a fellow with a 40' Searay would except overhauling his engines at 250 or even 500hours? The black engines are designed with mild cams for longevity, 1000 or even 2000 hours. Only us speed crazy boaters don't mind pulling and engine to rebuild it every 2-3years. Hell, I think that is a big part of the hobby for a lot of us... :drink: That sounds reasonable. |
Re: Extruded Honed?
except everyone keeps saying that my BLACK mag mpi are gonna be dead at 500 to 750.... nobody at all is talking 1000 or more...
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Re: Extruded Honed?
Originally Posted by stevesxm
except everyone keeps saying that my BLACK mag mpi are gonna be dead at 500 to 750.... nobody at all is talking 1000 or more...
I've got a friend with twin 330HP/454s in a Blackfin sport fish. 2200 hours and counting... |
Re: Extruded Honed?
Originally Posted by Pat McPherson
Well if they were well maintained and got run at 3500 rpm most of their life, 1000+ hours is not out of the question.
I've got a friend with twin 330HP/454s in a Blackfin sport fish. 2200 hours and counting... Steve I also have a friend with over 650 hours on his black 454 and he has little or no oil usage or blowby. I think good maintenance is the key. |
Re: Extruded Honed?
motors had 100 hrs on em when i got em and leak down was zero and the use no appreciable oil and run great... so i am confident in their condition... and i will maintain them properly... however i am likely to spend probably 70 % longer at WOT and max load then the prev owner did... i didn't buy this thing to just sit there and with the complete absence of any laws or enforcement down here, its likely to get a serious workout pretty routinely.
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Re: Extruded Honed?
Change your oil every 25 hours, use a good filter and good oil. If you don't use Merc stuff I like the 20/50 v-twin Mobil 1. You can do your drive at 50 hour intervals, along with your fuel filter/seperator and impeller.
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Re: Extruded Honed?
Since we are on the subject of intakes and such, I dragged up an old thread of mine...
http://www.offshoreonly.com/forums/s...light=AZ+Speed I tried to take some pictures but the batteries in my camera were dead. :rolleyes: So do any of you fellows thick I should swap my Merc. intake out for the AZ Speed intake for this coming season? |
Re: Extruded Honed?
Originally Posted by Pat McPherson
Since we are on the subject of intakes and such, I dragged up an old thread of mine...
http://www.offshoreonly.com/forums/s...light=AZ+Speed I tried to take some pictures but the batteries in my camera were dead. :rolleyes: So do any of you fellows thick I should swap my Merc. intake out for the AZ Speed intake for this coming season? Other than money what else do you have to loose? |
Re: Extruded Honed?
Originally Posted by stevesxm
fountainatlast...
do you really belive that knocking the casting flash off the inside of your intake manifold bought you almost 8 % more power... really ? having built, perhaps, 600 motors of every type i think i can say that thats simply not going to happen unless somebody at merc forgot a ratchet handle in there or something when it was first built. realistically, the extrude honing in my experience has been worth less than one percent on manifolds run back to back...before and after. it does, in fact knock the sharp edges off and tend to open cross sectional areas that are smaller than adjacent ones but that is NOT neccessarilly a good thing. intake manifold VELOCITY if much more important than volume... and shape is the absolute key to performance... and i can tell you authoratatively that a while a mirror finish on the inside of an intake port or intake manifold will FLOW bigger numbers it will not make as much hp as the very same manifold with a mat ( bead blasted) surface. the slight grain on the surface tends to keep the fuel in suspension making the mixture better as opposed to the mirror finish which tends to promote separation .... it is important in engine building to think combination and package... NOT magic bean. there are no magic beans. and combination is everything... take a nice clean sharp 450 hp motor and put a bigger cam in it without changing anything else and all you will do is make less power and use more fuel. and think about it for a second.... merc is in the business of selling you stuff.... do think for an INSTANT that if they could extrude hone their intakes and make 30 hp that you wouldn't see that in full page ads as far as the eye can see ? sorry... no easter bunny, no tooth fairy and no free 30 hp. Phil |
Re: Extruded Honed?
Originally Posted by BADKACHINA
Change your oil every 25 hours, use a good filter and good oil. If you don't use Merc stuff I like the 20/50 v-twin Mobil 1. You can do your drive at 50 hour intervals, along with your fuel filter/seperator and impeller.
cases of mobil 1 on the way even as we speak.... and appreciate interval advice.... trying to get a handle on that now... and by impeller...you mean the raw water impeller ? |
Re: Extruded Honed?
Originally Posted by stevesxm
cases of mobil 1 on the way even as we speak.... and appreciate interval advice.... trying to get a handle on that now... and by impeller...you mean the raw water impeller ?
Yes, sea pump impeller. |
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