mikesduster
Well-Known Member
Im just wondering what kind of flow numbers you guys are getting out of a X,J,O type head after porting???
Sb Head Flow Numbers
- Thread starter mikesduster
- Start date
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1wild&crazyguy
Banned
270's-280's int 180's-190's exh
Here are mine [j's] that I'm running on a 410 right now.
2.02-1.60 11/32 undercut at the stem and back cut, exhaust valve are ferrea.
.100 75 52
.200 142 101
.300 200 141
.400 249 169
.500 278 180
.530 281 184
.600 248 187
I used a harbor freight grinder w/ 3 different shaped '3 1/4'' long shank' carbide bits, and rolls to do a lil polishing.
Here are mine [j's] that I'm running on a 410 right now.
2.02-1.60 11/32 undercut at the stem and back cut, exhaust valve are ferrea.
.100 75 52
.200 142 101
.300 200 141
.400 249 169
.500 278 180
.530 281 184
.600 248 187
I used a harbor freight grinder w/ 3 different shaped '3 1/4'' long shank' carbide bits, and rolls to do a lil polishing.
Thats a hefty porting.
What are you doin Mike?
What are you doin Mike?
1wild&crazyguy
Banned
these are mostly 'in the works' pics, not the finished product but gives an idea of whats done to get there, or my version of it.lol
don't mind the floor kink either, it went bye bye.
And the one pic of the J and magnum head is to show why magnums can't do these numbers & are meant for 318's. ha ha
don't mind the floor kink either, it went bye bye.
And the one pic of the J and magnum head is to show why magnums can't do these numbers & are meant for 318's. ha ha
mikesduster
Well-Known Member
Nice numbers and pics!!!!!
1wild&crazyguy
Banned
Mopar cast some of the best heads of all the big 3.
Too many myths about going into water as well, more like into bolt holes and head bolt bosses, which is quickly remedied with studs/epoxy/thick washers under the head bolt.
Just raise the roof, skinny the guide-keep it long and flowing with the short turn, remove as much push rod pinch as you can but keep it straight and don't open it up to the gasket on that side or you'll create a more rounded speed bump at the pinch. To start
Too many myths about going into water as well, more like into bolt holes and head bolt bosses, which is quickly remedied with studs/epoxy/thick washers under the head bolt.
Just raise the roof, skinny the guide-keep it long and flowing with the short turn, remove as much push rod pinch as you can but keep it straight and don't open it up to the gasket on that side or you'll create a more rounded speed bump at the pinch. To start
bongy337
Just a guy who loves old mopars.
I have a proposition to those who have the means to test the following theory. Assemble a 360 block short block with a mild cam. Compression max 9.5 : 1(Bore not to exceed .030)
Cam spec not to exceed 230*@50, range max lift between .430 - 470- intake.
Use standard production heads with no trick porting/bowl blends/backcut, and mandatory production valve sizes 1.88 Intake / 1.60 exhaust. Use cylinder head casting numbers : "308", "596", "587", "894", "915","051" and "302". A TQ carb or Holly 3310 and your choice of Dual plane intake manifold. Now the challenge is what is the difference in horsepower between all these production heads?
Cam spec not to exceed 230*@50, range max lift between .430 - 470- intake.
Use standard production heads with no trick porting/bowl blends/backcut, and mandatory production valve sizes 1.88 Intake / 1.60 exhaust. Use cylinder head casting numbers : "308", "596", "587", "894", "915","051" and "302". A TQ carb or Holly 3310 and your choice of Dual plane intake manifold. Now the challenge is what is the difference in horsepower between all these production heads?
Not much except the 302 being a 318 head which would limit things in a bg way. All S/B heads flow reasonably close to each other as cast and new. Within a general area of approx 190-200 cfm intake.
The prize in heads (S/B) is how far they can go in ported form and how well they balnce out between the intake and exhaust ports.
Best as cast flow, in general are the X heads (Big valve) followed by the other letter heads.
Best balance in a S/B head *I beileve* belongs to the 308. It has exhaust port patterns of the W2 head.
The prize in heads (S/B) is how far they can go in ported form and how well they balnce out between the intake and exhaust ports.
Best as cast flow, in general are the X heads (Big valve) followed by the other letter heads.
Best balance in a S/B head *I beileve* belongs to the 308. It has exhaust port patterns of the W2 head.
Demon 408
Well-Known Member
Iron heads; casting # 4448308
Combustion Chamber Volume: 65cc; 2.02" Intake; 1.60" Exhaust
Flow Numbers
Intake Exhaust
0.100 Lift 64 50
0.200 Lift 132 98
0.300 Lift 184 136
0.400 Lift 226 175
0.500 Lift 254 189
0.600 Lift 247 196
I'm running these on my 408 with an LD-340 intake and Holley 950.
Dyno results:
443 HP @ 5800 rpm
460 Ft lbs Torq @ 4100 rpm
Combustion Chamber Volume: 65cc; 2.02" Intake; 1.60" Exhaust
Flow Numbers
Intake Exhaust
0.100 Lift 64 50
0.200 Lift 132 98
0.300 Lift 184 136
0.400 Lift 226 175
0.500 Lift 254 189
0.600 Lift 247 196
I'm running these on my 408 with an LD-340 intake and Holley 950.
Dyno results:
443 HP @ 5800 rpm
460 Ft lbs Torq @ 4100 rpm
HerboldRacing
340 Stroker
My heads flow 319... oh, wait... they're W5's! 
bongy337
Just a guy who loves old mopars.
Is this the result of a full porting/polishing? Or cleaning up the bowls and adding 2.02 valves?
Demon 408
Well-Known Member
Full porting job by my local Mopar machinist/engine builder.
1wild&crazyguy
Banned
what cam might you be running?
I'm running the same intake, smaller carb [for now], I wanna get a 950 or 1050 annular with a victor single plain.
Demon 408
Well-Known Member
I stopped porting at 267 in my first intake port.
Starting on my 2nt intake port with some new idea.
Cutting in the 2.02 w/nail head valve, netted me 21 cfm at .500" after i put a nice 3 angle cut to the seat it brought my .100" cfm up from 57 to 77 cfm.:cheers:
So there's a lot to be gained just by cutting in a 2.02" and having a 3 angle valve job done to it, while i'ts at the machine shop getting rebuilt.
then if you want more,.... smooth and round every thing in the port.................From there you real need a flow bench to know what works and what should have!..... but killed the flow.:angry7:
Just my 2Cents :-D
Starting on my 2nt intake port with some new idea.
Cutting in the 2.02 w/nail head valve, netted me 21 cfm at .500" after i put a nice 3 angle cut to the seat it brought my .100" cfm up from 57 to 77 cfm.:cheers:
So there's a lot to be gained just by cutting in a 2.02" and having a 3 angle valve job done to it, while i'ts at the machine shop getting rebuilt.
then if you want more,.... smooth and round every thing in the port.................From there you real need a flow bench to know what works and what should have!..... but killed the flow.:angry7:
Just my 2Cents :-D
EL5DEMON340
Well-Known Member
Did you use a mill to shorten down the long guide? did you completely remove the long guide tail that curves on the top of the roof ? i'm going to start on a set of J's for my 427" but will use 2.05 Ferras.
Just one more thing, cutting the push rod pinch as well and said above, will help as well with out needing a flow bench.
Justin? did you do any ssr laying back? the pictures above look like they were not touched...........
1wild&crazyguy
Banned
short side was worked...
You really need to see it in person.
In a J head port there is a 'peak' on the floor-'short turn'-ssr or whatever you wanna call it, i like to very slightly lay it back, keeping it tall and still some what steep but rolling into the VJ, which is key in working with the bowl & ssr shape.
See I never cut the ssr down lower than it's shortest peak, as in the wall hump go's but more importantly is properly blended down from the wall, along with removing some material from the straight wall itself.
say you guys ever hear of the idea that the floors shape/'length' is related to the roofs length? like the roof flow lags or is lower fps compared to the ssr or floor?
wet flow testing i think shows this/these patterns, where the port is working and where its just doing nothing.
see which ever part has the shorter path, will then pull the other down with it.
so like if the air reaches the seat on the ssr 1st, at that point lets say the head of the roof is still at the guide, the ssr will just pull it from the roof no longer flowing, but breaking up. inertia.
Draw a pic of a port then measure, mark it, the length of the roof & then the floor and see what you come up with.
just thinkin out loud, just drove 9hrs back through snow covered mountains w/storms/rain/hail/snow and chp escorts, should'a only taken 4 1/2-5hrs....
You really need to see it in person.
In a J head port there is a 'peak' on the floor-'short turn'-ssr or whatever you wanna call it, i like to very slightly lay it back, keeping it tall and still some what steep but rolling into the VJ, which is key in working with the bowl & ssr shape.
See I never cut the ssr down lower than it's shortest peak, as in the wall hump go's but more importantly is properly blended down from the wall, along with removing some material from the straight wall itself.
say you guys ever hear of the idea that the floors shape/'length' is related to the roofs length? like the roof flow lags or is lower fps compared to the ssr or floor?
wet flow testing i think shows this/these patterns, where the port is working and where its just doing nothing.
see which ever part has the shorter path, will then pull the other down with it.
so like if the air reaches the seat on the ssr 1st, at that point lets say the head of the roof is still at the guide, the ssr will just pull it from the roof no longer flowing, but breaking up. inertia.
Draw a pic of a port then measure, mark it, the length of the roof & then the floor and see what you come up with.
just thinkin out loud, just drove 9hrs back through snow covered mountains w/storms/rain/hail/snow and chp escorts, should'a only taken 4 1/2-5hrs....
1wild&crazyguy
Banned
all done by hand .
yes, the guide kink was completely removed and the guide itself was narrowed half way to the roof to the pressed in guide.
getting the width between the guide and straight side wall is most important as well, just don't go blind and end up in the head bolt tunnel.
And watch out, each head has 1 head bolt recess that is lower/shorter than the rest so you need to be careful on that one.... but if you want the flow just put a snug fit 'hardened' washer with some putty under it like I did.
72plymouthscamp
FOOSE ME
Check out this site it's pretty cool if your into the tech side of thing's. http://users.erols.com/srweiss/tablehdc.htm
octanejunkie
Mopar Padawan
Hmmm, interesting note on the magnums, I have actually heard the opposite regarding magnum heads and 318s - but i have not tried running them on a 318 I myself so I would not know
nice pics, wouldn't suck if they were individually labeled though
1wild&crazyguy
Banned
mag heads hav a lil more port volume than old 318 heads and a lil less than 360 la heads, so it's the medium if you will.
earthmover
in the tire smoke
hay 1wild&crazyguy are those the chevy 100 long valv. your useing?????
1wild&crazyguy
Banned
yeah. cheap, light weight, nail head valves.
The heads needed everything, so I made improvements while not spending any more, maybe even less, than stock replacement stuff.
earthmover
in the tire smoke
yea thats what i thought my buddy plans to go to a 205 and 1625 i think thats right for the ex. but i know the intake is right and 100 long...my other buddy had a set from hughs and thats what they used in them and man what a nice set of heads....should pick up a tab bite with just the valve change not to mention the valve job (5 angle more than likely)...
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