Porting small block 915 j-heads

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does coil bind happen before you get to your open pressure...
Trying to run the open height shorter than the coil bind height is a good way to end up with some chopped off cam lobes.

Obviously, at least one of those spring specs is incorrect.
Always have the springs tested, especially if it’s a particular brand/part number of spring you have no history with.
 
Hi Kma,

Hope the weather is good in Sweden as its super here in Kent UK!
I have the sliced up 'J' head (from Weslake Eng.) and its very different to the later heads, in the waterways?
Was wondering if the castings were the same internally but they is totally different indeed.
I will take some pictures for you tomorrow.
That later stuff looks real bad for porting to me???:wtf:
John from UK
 
Hi Kma,

Hope the weather is good in Sweden as its super here in Kent UK!
I have the sliced up 'J' head (from Weslake Eng.) and its very different to the later heads, in the waterways?
Was wondering if the castings were the same internally but they is totally different indeed.
I will take some pictures for you tomorrow.
That later stuff looks real bad for porting to me???:wtf:
John from UK

I have a pile of late 360 heads that have problems, coupled with bad castings so I only go with 'J' heads as they is super!!!
I have several heads and engines from the Weslake Engineering shop here in Kent England.(closed down in the 80's)
They were employed by Mother Mopar in the late sixties, early seventies to 'refine' head castings for NASCAR etc.
The Weslake 'J' head I tried to copy in the past but always went into the water jackets when 'TRYING' to making a perfect twin!
So now I have done a 'nearly' copy to stop wasting many hundreds of hours on SCRAP!
I suppose the 'Weslake'-'J' head was a new casting in 70/71 without the rust issues of the 50 year heads we have now???:drama:
 
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So how do we upload pictures?
Every site I go on seems to be different??
Took the pics with my phone and downloaded onto my computer and what now???

Wow I DiDiT! how did that happen, top class technophobe at work here...:mob:

340 J floor waterway.jpg


340 J cutaway with template.jpg


The floor of the J port is about 1" from the machined face in stock casting (approx).
This J port head cutaway from Weslake Eng. is approx 7/8" to the highest point above the waterway.
I have another single complete Weslake 'ported' head that I tried to copy in the past but went through in several places trying to do it exactly the same.
I suppose a rust free unused 50 year old head doesn't have 50 years of corrosion waiting to 'bust through' like all my other heads lol...

View attachment 1715536981

later 360 head comparison

360 port cut.JPG
 
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A couple more pics.

340 J centre waterways.jpg


As you go back behind the valve you can see how thin the casting gets, always break through here if you get greedy!!!:wtf::BangHead::mad:

340 J ported.jpg


Port looks huge if you have the 'right' casting and the bravery to go that far...:drama::realcrazy::rofl:

20200529_113224.jpg


BACKWARDS 'J', THATS ME LOL
 
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Questions for STR....

Is there a complete cylinder on those Weslake heads that could be flowed?
Have you done that?
Have you tested one that you ported where you were trying to copy the Weslake job?

Have you measured the pushrod pinch of the port with the white paint?
 
Hi PRH,

Yes there is a complete 340 J head that is ported by Weslake's here.
The machine shop where I used to work in the Noughties had a flow-bench, but sold it in 2002 when they moved premises, so I never got to use it!
I have several heads that need flow testing from Weslake in the 70's and few others too from 'porters' here in the UK too.
Rob Loring of ICE Automotive did a very nice set of raised port BB heads along with Jeff Hauser and USA's finest Koffel's too.
Not seen many trick S/B iron heads as they are less favourable here in the UK?
I always use an 'E' gauge when doing the 'pushrod pinch' normally get around an inch with smallblocks and a 'tad' more with Bigblocks.
Some Bigblock heads I have are 'raised port' approx 1/8" to 3/16" but the 'ICE' heads are nearly 1/2" with 'flow-guides' cemented into the floor to make the port 'normal size again.
Better with pics I think.
STR-Jon

ps pushrod pinch is always, 'grind to you see daylight then go back 20 thousanths' lol...:BangHead::BangHead::BangHead:
 
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Back in the day if you wanted to run a TEN, you needed an Bigblock here in the UK.
Now I see guys running TEN's with smallblock stroker's and even NINE's ...:steering:
Yes Aluminum heads were around but us 'Dynosaws' loved doing it the hard way, with IRON!!!
Porting skills are a dying, if not 'lost art', so we just like doing it for fun, especially in lockdown...:thumbsup:

If we ever get to use them on the track or in the Boondocks again is another matter???:confederateflag:
 
Hi KMA,
Hope the WESLAKE 'J' head cutaway helps you with your headwork.
I had only read the first page and saw the cutaway was NOT a 'J' head but a late casting.
I ONLY just started reading the next few pages and was very shocked at a 'pie flinging' match going on?
No one cares about IRON heads anymore so why are folks going to WAR over them???
After watching the HOTROD articles with Steve Dulcich and the converted EDDY heads, then iron is 'OLD-HAT'!!!
I have done a lot of B/B and POLY-318 iron heads in the past but knew that 'J' were/is the 'bees-knees' so didn't need porting. (so I thought)
Then I finds out 'they do' and they is a ***** to get right, so the challenge was to see how hard they is to get them flowing good.

I always had the WESLAKE cutaway 'J' and a complete head and never really studied them that closely till now?
WOW the work is treemendous!

Seen a lot of 'good guys' come and go on these sites and all they was trying to do was help out and be nice.
What's wrong with being NICE?
My wife says "nice guys always come last" who cares, I just wanna join in and have some fun...:thankyou:

She just spent a week in a CORONA ward (very unwell indeed) and says we are all PLONKERS!!!
GROW-UP...:soapbox: and ''get a life'' she says to me...

Do something constructive, like knitting and sewing?
 
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The restore matching number guys are still stuck with iron heads as are some stock racing classes
actually ported Iron may flow better below .400
 
Hi KMA, blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah, blah blah. "Insert lame emojis here" blah blah blah

Well said.
 
Unofficial Moparman from the UK!

I've been doing IRON heads for 40 years now, never been down the track with an Ali head myself.
Dream was to run a NINE with IRON, probably could have done it if I had the right Mopar! (lighter)
But my best was 10.66 which is quite IRONic for us Brtits lol:mob:
My moparmate did a 10.40 in my car with the same set-up, so that made me look real LAME!!!:wtf:
(My 68 Dart was quite heavy for a street class set-up, but IT was a real street car @2800lbs.)
With a Koffel 547ci motor and Indy maxx heads it ran 8.20 @ 180 on pump gas...:steering:(in the 90's) here and in the US of A! THAT'S QUICK FOR A STREET CAR!

My next plan is to get a british car (much lighter) from the 60's with a nice 340/360 set-up and 'JAY' heads to run that elusive NINE!

Wish me luck and stop the BUN fighting, lifes too short for all this BOLLOCKS coupled with CORONA too...:rofl:
 
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Unofficial Moparman from the UK!

I've been doing IRON heads for 40 years now, never been down the track with an Ali head myself.
Dream was to run a NINE with IRON, probably could have done it if I had the right Mopar! (lighter)
But my best was 10.66 which is quite IRONic for us Brtits lol:mob:
My moparmate did a 10.40 in my car with the same set-up, so that made me look real LAME!!!:wtf:
(My 68 Dart was quite heavy for a street class set-up, but IT was a real street car @2800lbs.)
With a Koffel 547ci motor and Indy maxx heads it ran 8.20 @ 180 on pump gas...:steering:(in the 90's) here and in the US of A! THAT'S QUICK FOR A STREET CAR!

My next plan is to get a british car (much lighter) from the 60's with a nice 340/360 set-up and 'JAY' heads to run that elusive NINE!

Wish me luck and stop the BUN fighting, lifes too short for all this BOLLOCKS coupled with CORONA too...:rofl:
Never met ya, but welcome, enjoy.
Ps we are a joking bunch sometimes..
 
Hi Mopar Official,
Thanx for the reply.
Always happy to share Mopar knowledge with others but in recent years folks have become a bit grumpy?
I have visited the States many times and had wonderful experiences meeting fellow Moparmen and Moparladies too. ( so we might have met?)
There can be a stark divide between 'hobbyist' guys and the dealer come hardcore restorer millionaires!
Some are happy to own and 'old Mopar' with a 318 and even a six cylinder , where others only want mint hemi cars.
There is a place for everyone in the Moparworld and Mopar 'snobbery' just isn't welcome in my book!
If I want to spent 100 hours porting a rusty 50 year old cylinder head, then that's for me to choose.
Me and many others don't need a lecture on the rights and wrongs of 'doing-it'.

Yes I would like a SERDI and a full workshop with a dyno, like an old 'CA' friend Tom Nelson and build 2000hp hemi's , but that ain't gonna happen for a pensioner like me...

America should be happy that she has a Muscle car industry that spans the WORLD!
UK dragstrips are a rare thing now with only ONE recognised track which is Santa POD raceway.
The 'writing is on the wall' for us Dinosaurs from the 20th Century.
Machine shops that can do V8 engine work are getting very rare too and the end is in site for OIL-BURNERS!!!:mob:

Lets just enjoy the time we have left and 'be friends' meeting up whenever possible to talk of the glory days of MOPAR MUSCLE...:thankyou:

God Bless AMERICA and her MOPARS!!! where ever they might BEE!:usflag::usflag::usflag:
 
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Hi Mopar Official,
Thanx for the reply.
Always happy to share Mopar knowledge with others but in recent years folks have become a bit grumpy?
I have visited the States many times and had wonderful experiences meeting fellow Moparmen and Moparladies too. ( so we might have met?)
There can be a stark divide between 'hobbyist' guys and the dealer come hardcore restorer millionaires!
Some are happy to own and 'old Mopar' with a 318 and even a six cylinder , where others only want mint hemi cars.
There is a place for everyone in the Moparworld and Mopar 'snobbery' just isn't welcome in my book!
If I want to spent 100 hours porting a rusty 50 year old cylinder head, then that's for me to choose.
Me and many others don't need a lecture on the rights and wrongs of 'doing-it'.

Yes I would like a SERDI and a full workshop with a dyno, like an old 'CA' friend Tom Nelson and build 2000hp hemi's , but that ain't gonna happen for a pensioner like me...

America should be happy that she has a Muscle car industry that spans the WORLD!
UK dragstrips are a rare thing now with only ONE recognised track which is Santa POD raceway.
The 'writing is on the wall' for us Dinosaurs from the 20th Century.
Machine shops that can do V8 engine work are getting very rare too and the end is in site for OIL-BURNERS!!!:mob:

Lets just enjoy the time we have left and 'be friends' meeting up whenever possible to talk of the glory days of MOPAR MUSCLE...:thankyou:

God Bless AMERICA and her MOPARS!!! where ever they might BEE!:usflag::usflag::usflag:


:thumbsup::thumbsup:
 
Long time no see.
First head done except valve guides,valve job and blending the bowl for 1,94"s + finishing up with "tootsies"
Can say it takes time , ha ha , especially when one never done it before. Been going forward carefully. Probably takes much less time for the second head when one know where to be grinding.
Excuse the extremely good pictures but is there a trick to get them better


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Nice work:thumbsup:

That much work on the guide boss eats up time....... no matter who’s doing it.

Thanks. Maybe it’s overkill but my thoughts was: the less thats in the way the better
 
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