PRH
Well-Known Member
Is the 1hp/ci supposed to happen with ex manifolds or headers?
If manifolds........ 318 manifolds?
If manifolds........ 318 manifolds?
You cant take an accurate measurement like that. You need a plate or the water you're using will buldge and read HIGHER than is actual. That could be 2cc or so off. The heads are born as 64cc and have been about the only 318 head to be spot on with printed specs.OK
The head gaskets are the .028 ths Mr. Gaskets.
And the Factory 9.2:1 valve relief flat top pistons (std.) sit .040 down in the hole.
I know cause I measured them. The 1969 318 block was not decked, untouched .
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With everything figured in on that '69 318 build, we figured came out to 9.5:1, Pistons, 302 closed chamber heads, and the thin head gaskets.
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That was also figuring a little deduction for the valve reliefs in the pistons too.
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OK, Brian just now got back to me with his cr calculations.
59cc 302 chambers
View attachment 1716035125
Brian's Quote:
"I have numbers he will need to be accurate. My calculation is 9.6:1."
Cranking psi will tell.With the 10:1 CR, it shouldn't need as much spark lead as a factory build.
And that's on top of the possibility that the heads actually help create a more homgenous mixing even at low rpm.
I think its going to need high test (93 anti-knock) on the street unless the cam is such that it bleeds some of the compression off. That's stuff that's above my pay grade.
I was just trying to point out the sort of things knowing the CR can effect. In other words why its worth the measuring the actual cc. George added the photo after I responded but I still didn't pickup on the lack of plexiglass until you pointed it out. It sounded like a stock build other than the heads? But my thinking generally is that a cam ought to be selected in conjunction with the CR and knowing the lift where flow starts to choke.Cranking psi will tell.
Still run it up high for base, but the total...is either do the math.. or wait and see what it likes. 25-30 I would guess..but again, the cam is the rest of the picture.
I'm just responding to this post and haven't read any details other than it
You watch the wiengardener smallest port w/ highest flow port myth ? He examplifys choke. He kills the flow, does it by bench n basically fks the range/depression so its exaggerated some. It's just an example. It will fall off, yes, it wont power on up past the cam range as it could. Can be a thread starter. Spier pops off on it hrs later too. The sheer timing of those 3 videos is remarkable ...soon after the DV MIA 318.I was just trying to point out the sort of things knowing the CR can effect. In other words why its worth the measuring the actual cc. George added the photo after I responded but I still didn't pickup on the lack of plexiglass until you pointed it out. It sounded like a stock build other than the heads? But my thinking generally is that a cam ought to be selected in conjunction with the CR and knowing the lift where flow starts to choke.
Hows your j head revisit going?
Caught up.....again
No new thoughts.
Which head porter do you know that just picks up ANY head and just ports it...............Do you take your mopar heads to a ford or chevy guy that's never touched them or do you find a guy whos done more sets than he can remember and figured stuff from do so many. All this talk of investing time and development would be the case for any head porter on any new head.
SO you port every head the same because they are all the same? Its funny when I read stuff from guys that do this for a living say that over time they figure out how to get more flow for less work out of the same casting........Do you honestly think a Chevy head knows it’s a Chevy head. I’ve done ford, Volkswagen, Chevy, and yes Mopar and the thinking is all the same.
318 manifolds I believe, shouldn't be the worst restriction at 325 ish hp, there's a dyno manifold shootout on a 300 hp 5.9l and there 5 hp between 318 & 340 manifolds and 8-16 hp compared to headers.Is the 1hp/ci supposed to happen with ex manifolds or headers?
If manifolds........ 318 manifolds?
SO you port every head the same because they are all the same? Its funny when I read stuff from guys that do this for a living say that over time they figure out how to get more flow for less work out of the same casting........
If you need to make out they spent a ridiculous amount of time grinding on a set of heads then it suits your narrative to ignore the fact familiarity with a casting makes a big difference in how long it takes to get flow out of them.You guys are talking past each other.
"Thinking is the same" - that is the concepts apply regardless.
"over time they figure out how to get more flow for less work out of the same casting" - How to get it done varies and takes learning.
Is there really an arguement here?
Both are true.
Wonder how much Charles has spent doing that............Because he isn't familiar with where the easy gains are to be had. Its funny how GTX John can get OVER 200 cfm with just a valve job.Let’s just say you can grind like crazy in areas that you think a head needs grinding and never pick up 5 cfm.
OK. I'll bite.
What's the cam?
Yes. Thanks.Think you are asking with the LD4B Intake?
Lift: 430/444
Duration: 268/276
Lobe Center 114
Or the Melling SPD-22
Lift: 429/444
Duration: 279/289
Lobe Center 112/116
SPD-22 is in good supply available for purchase online.
If you need to make out they spent a ridiculous amount of time grinding on a set of heads then it suits your narrative to ignore the fact familiarity with a casting makes a big difference in how long it takes to get flow out of them.
Wonder how much Charles has spent doing that............Because he isn't familiar with where the easy gains are to be had. Its funny how GTX John can get OVER 200 cfm with just a valve job.
You're making my point for me. Would you call Charles a Mopar head specialist? No? then why pretend it takes forever to get flow out of these small castings if someone knowledgeable can get over 200 cfm just by a valve job.Stock and super stock guys are a different breed and they pay real good money for those valve jobs. I flowed a set (small block Mopar) for a buddy of mine and they hit a certain number and never went up and didn’t fall like most of us struggle with. He asked me if I could freshen his valve job for him and I told him absolutely not. I said if you want to get a good laugh ask the previous guy that did the valve job what angles he used. He called me the next week the guy laughed at him. Lol. Trust me it’s not. 60-45-30.
I haven't touch them head in years, or any, for that matter, in years.Hows your j head revisit going?
I found the thread where you say you hit a wall at 250's then 260..but it wouldn't stabilize after .520 or so?
What's your thoughts on using a Serdi? "Machining seats and angles with a carbide machine tool instead of grinding them with a rock".Stock and super stock guys are a different breed and they pay real good money for those valve jobs. I flowed a set (small block Mopar) for a buddy of mine and they hit a certain number and never went up and didn’t fall like most of us struggle with. He asked me if I could freshen his valve job for him and I told him absolutely not. I said if you want to get a good laugh ask the previous guy that did the valve job what angles he used. He called me the next week the guy laughed at him. Lol. Trust me it’s not. 60-45-30.
They are smaller at the head, did not measure the runner.Are the ports smaller on the single plane than the LD manifold?
What's your thoughts on using a Serdi? "Machining seats and angles with a carbide machine tool instead of grinding them with a rock".
I’d go comp xe250h similar lift and @ .050 specs but ground on 110 lsaThink you are asking with the LD4B Intake?
Lift: 430/444
Duration: 268/276
Lobe Center 114
Or the Melling SPD-22
Lift: 429/444
Duration: 279/289
Lobe Center 112/116
SPD-22 is in good supply available for purchase online.