420 lbs-ft out of a 5.0l is pretty good that's like decent 340 or a mild ish 360, you should have no problem hitting 475 lbs-ft, that's 1.16 lbs-ft per cid that would definitely on the low side for any decent 408.
What would it take to make 1.44 lbs-ft per cid ?
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It does represent efficiency, but for most efficiency ain't hugely important is easier to generally build a larger less efficient engine to hit your power and rpm goals.
It not necessarily important in making hp but it's important to where that hp is made rpm wise, In highly competitive race classes with rule restrictions it becomes very important but for most of us if you in the 1.17-1.27+ tq:cid range with a fully built engine your doing ok and your build is above that you can give yourself a nice pat on the back
But if you look at the 515 hp @ 5,900 rpm 371 vs 408, the 371 is able to match the 408 peak power and more importantly for this discussion rpm with nothing really exotic, it just seems the top end is science a little better then the 408's. I'm pretty sure it's mainly due velocity and cam specs, the question is what criteria were they using to make these decisions, people on here talk about the importance of velocity but only in some abstract way, and their always concerned about too little but rarely about too much, not about what's is right? And how to figure that out.
I don't know man. I don't need or want to go back to my engineering classes here. All I can say is that when I look at some engines that are known for their specific output, they don't always have really high specific torque output.It does represent efficiency, but for most efficiency ain't hugely important is easier to generally build a larger less efficient engine to hit your power and rpm goals.
It not necessarily important in making hp but it's important to where that hp is made rpm wise, In highly competitive race classes with rule restrictions it becomes very important but for most of us if you in the 1.17-1.27+ tq:cid range with a fully built engine your doing ok and your build is above that you can give yourself a nice pat on the back
But if you look at the 515 hp @ 5,900 rpm 371 vs 408, the 371 is able to match the 408 peak power and more importantly for this discussion rpm with nothing really exotic, it just seems the top end is science a little better then the 408's. I'm pretty sure it's mainly due velocity and cam specs, the question is what criteria were they using to make these decisions, people on here talk about the importance of velocity but only in some abstract way, and their always concerned about too little but rarely about too much, not about what's is right? And how to figure that out.
The 5.0 coyote is at 1.4 ft lbs/cu in. Seems pretty high compared to others.
But looking at some other engines that I like:
The s2000 inline 4, the bmw e92 4.0L V8, neither of these come close to the so called high efficiency numbers. But they are both very fast engines for their displacement and generally highly regarded.
I think in this case, higher tq:ci got a lot more to do with dialing in the right velocity for higher ve%, among other things.
Just watched a Richard Holdener video on a Stock LS 6.0l so basically a 365 and made 515 hp @ 5,900 and 492 lbs-ft (1.34 lbs-ft per cid) with a 238° on 112 cam and headers. Same peak power and rpm as the 371 & 408 and similar torque as the 371. No wonder people like the 6.0ls it's basically working like a 408.
Seems to me if someone made for a stock stroke 360 a well put together cam intake and head package for around 500 hp @ 6000 rpm and 500 lbs-ft it would probably be a decent seller, 408 like power & rpm with a standard 360 short block.
Seems to me if someone made for a stock stroke 360 a well put together cam intake and head package for around 500 hp @ 6000 rpm and 500 lbs-ft it would probably be a decent seller, 408 like power & rpm with a standard 360 short block.
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I was reading through this thread. A 457 horse 318 would be fun. How about a 393 horse 273?
junkyardhero
Well-Known Member
all it takes is a 630 solid roller with about 300 duration and some heads flowing about 240
it'd be a fun burger cruiser, but you'd need like, all the gear and converter you could stand.
RAMM
Well-Known Member
It's all right in the specs listed. Right before the contest I was messing with intake runner extensions in the manifold and I saw a best of 513 Tq/526 HP--I got greedy and tried to extend them and shape them for even more and lost a bit. Left the day before with 508 TQ/522 HP. I was stoked to see 1.38 tq/ci. J.Rob
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RAMM
Well-Known Member
RAMM
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You are correct again, TONS of time was spent on those heads. Every single port was flowed and worked and reflowed until I was happy with them. In the end they all flowed within 3 cfm at all lift ranges and they flowed 275-277cfm on a 4.06" bore. So much work and effort went into those. J.Rob
RAMM
Well-Known Member
Is there a velocity number you shoot for ?
From what I understand 260-285 fps based off average cross section is the supposedly the sweet spot but seems to be asking for fairly large ports, if I'm doing the calculations right seems based off 371 with the 277 cfm heads would need a average csa of 2.56" & 207 cc for 260 fps.
Dan the man
Well-Known Member
Engine Labs got 434 ft.lb torque and 387 horsepower at 5,900 rpm's. I don't know if they did or not, I'm only going by what the article said. Cam .477/.480×224*/230* @0.050". They posted a dyno chart but I don't know how to load it here. Just wondering what you guys think about this. I don't know it as a fact either
Dan the man
Well-Known Member
387 hp at 5,900 rpms seems fairly high rpms for 387 hp. The 434 torque is an ok number for a 360.
Like to see the article if you could copy and paste the link.
Dan the man
Well-Known Member
Left Click on the browser address bar, the address now should be high lighted.
Right click and select copy.
The in the reply box on this forabodiesonly page right click and select paste.
RAMM
Well-Known Member
With an EQ Magnum velocity is very very high, in fact its much higher than what could be considered normal. Those heads had nowhere near CSA of 2.56". 207cc? CSA of 2.56" Not a chance--more like 185cc-186cc if I remember. When I took those heads to the largest I dared, for EMC 2012 on a 416ci, I almost found water @ 189cc and I made a pinhole in the top of a runner. Could you make these heads support 7000RPM peak HP @ 371ci? I doubt it.
These heads work so well because of the shape-which trumps cfm & velocity even when the velocity is 450+fps @ the S.S. Like any Mopar head with the exception of the HEMI you can't make them too big. Can you make them too big in the wrong area? Like any head-Yes. J.Rob
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Now, Now, everyone knows the chart says 350 fps is the MAX possible. (sarcasm)
That chart is talking average. Earlie A did a whole thing on it, 350 fps average is the max velocity at 28" there no more energy to pull more.
185-186 cc works out to be about 290-292 fps for a 277 cfm head and chart says should make very good hp and torque.
I've never said this chart is accurate or should be followed, but the little velocity information out there I'm using at a basis as I gathered info and seeing if this chart has any merit. J.Rob's heads where barely slightly smaller than the chart recommends and he did said that bigger was desirable when done right which would of be in recommended size. Now again not saying this chart is right but I'll put this one in the win category for the chart.
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RAMM
Well-Known Member
A little (longwinded) backstory on that 371 because its pertinent to this discussion and sometimes I love to WouldaCouldaShoulda.
I had been using EQ heads since the early 2000's--Ford GTP's, Chevy (which were awesome) there was no Mopar offerings at that time, and then I kinda forgot about them from 2004- until early 2009. A catalog was sent to me and I noticed the CH-318A and CH-318B. I ordered a set for a mild street build 360 with an HR cam, immediately noticed the short stock I.H. and proceeded to bore the guides to 11/32" and use much longer Chev style valves and rockers. That engine made me think the dyno was out of whack as it made what I thought was remarkable power 470+ HP/470+TQ. Over the next couple of years I used them when budget and the customer allowed. Some were tested and some were not, my takeaway was that the dyno results were always impressive. Even the ones that did not get tested I had feedback that implied-WOW.
Fastforward to spring of 2011 and although I had entered and was accepted @ EMC 2011, I had thoughts of not really building anything serious or even anything at all. Time and $$$ were always an issue and I had done the EMC twice already and I knew my chances at a win were zero and I thought my chances at a third consecutive feature magazine article were zero-hence my lackluster attitude. So in the background I had built a nice 360 circletrack engine for a good friend of mine with W2 heads and a SFT cam, W2 intake, and 500cfm 4412 as per the rules...(447hp/440tq). He runs it for the season May-1st week of Sep. <<<We'll come back to this.
So during that summer I have no idea what I'm going to build for the EMC which is always the 1st week of October. I didn't know what displacement, bore size, stroke etc...I didn't even really have a decent smallblock core to use and the idea of using the EQ heads hadn't really been cemented either--but they were there in the back of my mind.
I had been working on another 360 build for a customer and he wanted ported EQ's. As I began shaping a bowl I realized how much better quality the iron was and how much time this was going to take and my wheels started turning. Enter the CNC idea. I took a head and mounted it on our 3axis CNC because I didn't really want to get too crazy and just wanted to knock some material out of the bowls with a simple interpolation program. So a small program was written with a custom venturi style shape and some ovality. Chips were made and off to the flowbench. A 2.02" valve size and ZERO blending=272cfm!!! Keep in mind there was a huge ledge where the CNC machining left off. I thought this was going to be so easy to get these into the 290's--was I wrong, but still even blending the ledge out only netted about 275-277cfm. Anyways this was in July 2011 and thats when I thought about using them on the the 371 shortblock in my buddys CT car. So I found the T&D shaft rockers on Moparts, and proceeded to make the heads the best I could for the month of August while I patiently waited for the CT season to be over. It was an excruciating wait because that engine could have expired while in the car or even on the dyno just weeks or days before the EMC.
Back to the heads--So like I said in an earlier post I had time to really scrutinize every port and exactly half of them needed substantial rework. 4 of them flowed the same at all lifts and 4 of them were as much as 10cfm behind at all lift ranges and turbulent as well. Anyways I sourced an old Weiand 7545 (awesome intake) and took my best shot at a custom roller cam from Comp. My friend pulled his engine the first week of September--I re-ringed it and changed the cam and top end which took me into the third week of September as I had to wait for different length pushrods. So here we are basically one week away from having to leave for the EMC and testing begins. I was shocked when it outscored 2010's 367 w/W2's on account of the incredible TQ. Like I said a bit of tuning and 513 ft/lbs on test 6 or 7 and off comes the manifold. I cut some runner extension ears out of .187" aluminum and tack welded them in thinking I'd pick up 5 pts. Nope--lost something like 11 ft/lbs. Off comes the manifold and I hack about half of the extensions off. Nope still down but coming back a bit. Off comes the manifold again and I wind up breaking 2 of the extensions off right at the weld. Oh well it worth a shot right? I try it again and have to live with it as we have to leave the next evening.
Anyways we get to Ohio and Johnny Hunkins spots the heads right away as he is good friends with Eric Haughland @ EQ--he is all excited and films some of the dyno footage himself and sends it Eric's way. That engine was so strong at the bottom it never wavered or faultered or fell in rpm. At full load on the brake before the engine is "released" for its acceleration run you will often see and hear the TQ and RPM drop a bit--Not that engine. From our prior 2 years experience at EMC the dyno operator liked to F@#$ with the newer teams and would deliberately hold us @ 2300-2400 rpm for as much as 10-20 seconds--which is a lifetime. That engine was different--It did not fall off or go into detontation at all, it just sat there and sat there and sat there making 400+ ft/lbs @ 2500rpm. The dyno operator made a comment and even the tech director Wes did as well. I still wonder what that engine could have done being fresh and with a trick set of pistons with a better ring pack and more time--always more time. LOL. That engine was thee best bang for the buck EMC engine I ever did. Sorry for the longwinded story.
The 4 takeaways here are:
1. I should have left the ridge and tested with a 2.02" valve. ( I got greedy chasing #'s)
2. I should have committed to a plan and built a slightly smaller cubic inch before September
3. I should have recognized I would likely not exceed 1.38 ft/lbs/ci and leave well enough alone.
4. I should have ordered a pallet of EQ heads and waited...Or bought bitcoin--LOL.
J.Rob
I had been using EQ heads since the early 2000's--Ford GTP's, Chevy (which were awesome) there was no Mopar offerings at that time, and then I kinda forgot about them from 2004- until early 2009. A catalog was sent to me and I noticed the CH-318A and CH-318B. I ordered a set for a mild street build 360 with an HR cam, immediately noticed the short stock I.H. and proceeded to bore the guides to 11/32" and use much longer Chev style valves and rockers. That engine made me think the dyno was out of whack as it made what I thought was remarkable power 470+ HP/470+TQ. Over the next couple of years I used them when budget and the customer allowed. Some were tested and some were not, my takeaway was that the dyno results were always impressive. Even the ones that did not get tested I had feedback that implied-WOW.
Fastforward to spring of 2011 and although I had entered and was accepted @ EMC 2011, I had thoughts of not really building anything serious or even anything at all. Time and $$$ were always an issue and I had done the EMC twice already and I knew my chances at a win were zero and I thought my chances at a third consecutive feature magazine article were zero-hence my lackluster attitude. So in the background I had built a nice 360 circletrack engine for a good friend of mine with W2 heads and a SFT cam, W2 intake, and 500cfm 4412 as per the rules...(447hp/440tq). He runs it for the season May-1st week of Sep. <<<We'll come back to this.
So during that summer I have no idea what I'm going to build for the EMC which is always the 1st week of October. I didn't know what displacement, bore size, stroke etc...I didn't even really have a decent smallblock core to use and the idea of using the EQ heads hadn't really been cemented either--but they were there in the back of my mind.
I had been working on another 360 build for a customer and he wanted ported EQ's. As I began shaping a bowl I realized how much better quality the iron was and how much time this was going to take and my wheels started turning. Enter the CNC idea. I took a head and mounted it on our 3axis CNC because I didn't really want to get too crazy and just wanted to knock some material out of the bowls with a simple interpolation program. So a small program was written with a custom venturi style shape and some ovality. Chips were made and off to the flowbench. A 2.02" valve size and ZERO blending=272cfm!!! Keep in mind there was a huge ledge where the CNC machining left off. I thought this was going to be so easy to get these into the 290's--was I wrong, but still even blending the ledge out only netted about 275-277cfm. Anyways this was in July 2011 and thats when I thought about using them on the the 371 shortblock in my buddys CT car. So I found the T&D shaft rockers on Moparts, and proceeded to make the heads the best I could for the month of August while I patiently waited for the CT season to be over. It was an excruciating wait because that engine could have expired while in the car or even on the dyno just weeks or days before the EMC.
Back to the heads--So like I said in an earlier post I had time to really scrutinize every port and exactly half of them needed substantial rework. 4 of them flowed the same at all lifts and 4 of them were as much as 10cfm behind at all lift ranges and turbulent as well. Anyways I sourced an old Weiand 7545 (awesome intake) and took my best shot at a custom roller cam from Comp. My friend pulled his engine the first week of September--I re-ringed it and changed the cam and top end which took me into the third week of September as I had to wait for different length pushrods. So here we are basically one week away from having to leave for the EMC and testing begins. I was shocked when it outscored 2010's 367 w/W2's on account of the incredible TQ. Like I said a bit of tuning and 513 ft/lbs on test 6 or 7 and off comes the manifold. I cut some runner extension ears out of .187" aluminum and tack welded them in thinking I'd pick up 5 pts. Nope--lost something like 11 ft/lbs. Off comes the manifold and I hack about half of the extensions off. Nope still down but coming back a bit. Off comes the manifold again and I wind up breaking 2 of the extensions off right at the weld. Oh well it worth a shot right? I try it again and have to live with it as we have to leave the next evening.
Anyways we get to Ohio and Johnny Hunkins spots the heads right away as he is good friends with Eric Haughland @ EQ--he is all excited and films some of the dyno footage himself and sends it Eric's way. That engine was so strong at the bottom it never wavered or faultered or fell in rpm. At full load on the brake before the engine is "released" for its acceleration run you will often see and hear the TQ and RPM drop a bit--Not that engine. From our prior 2 years experience at EMC the dyno operator liked to F@#$ with the newer teams and would deliberately hold us @ 2300-2400 rpm for as much as 10-20 seconds--which is a lifetime. That engine was different--It did not fall off or go into detontation at all, it just sat there and sat there and sat there making 400+ ft/lbs @ 2500rpm. The dyno operator made a comment and even the tech director Wes did as well. I still wonder what that engine could have done being fresh and with a trick set of pistons with a better ring pack and more time--always more time. LOL. That engine was thee best bang for the buck EMC engine I ever did. Sorry for the longwinded story.
The 4 takeaways here are:
1. I should have left the ridge and tested with a 2.02" valve. ( I got greedy chasing #'s)
2. I should have committed to a plan and built a slightly smaller cubic inch before September
3. I should have recognized I would likely not exceed 1.38 ft/lbs/ci and leave well enough alone.
4. I should have ordered a pallet of EQ heads and waited...Or bought bitcoin--LOL.
J.Rob
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