360 head porting for big power (500HP ?)

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txstang84 said:
:happy1:

Can't wait to see how these do on your 360!
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Me too. I'm actually building another 360 for these heads. Pretty much have everything parts wise on the shelf. 0 deck JE flat tops, reconditioned and lightened Magnum rods, rod and main bearings I scored off Ebay for a steal, couple of std cast cranks, Beehive springs and retainers, Crane ductile iron rockers. Winter project I guess. Maybe get it on the dyno.
 
Makin HP on a mac 'n' cheese budget ain't easy. Laugh my *** off when my $1500 Mopar puts it down as well as some the brand X crap does for 3X or more the money.
 
skrews said:
Me too. I'm actually building another 360 for these heads. Pretty much have everything parts wise on the shelf. 0 deck JE flat tops, reconditioned and lightened Magnum rods, rod and main bearings I scored off Ebay for a steal, couple of std cast cranks, Beehive springs and retainers, Crane ductile iron rockers. Winter project I guess. Maybe get it on the dyno.
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Man, I can't wait! Do you already have a bumpstick in mind? Solid or solid roller perhaps? I'm very interested to hear about the beehives-I've looked into those once or twice for my 383 heads. I know they're pricey, but from all I've read thus far, they perform better with a smaller footprint, higher lift, and less weight.

I'll definitely be looking at this one though--pretty sure my brother will be too...he's compiling some parts for a 340 build
 
Got a 248* @.050 106+3 .563 lift single pattern Hughes solid on the shelf. Thinking about going bigger though. Probably talk to the guys at Bullet.
I like the beehive springs. Much lighter retainer/upper coil mass than standard springs. Will run more RPM for a given amount of pressure. You can get them from Summit as Trick Flow 16918-16 $130 as opposed to Comp 26918 $180. They are all made by PAC anyway.
 
I may have missed it but can you tell us what size the chambers are? If I'm not mistaken, 308 heads usually come in around 68-72cc. Were the surfaces cut at all?

Couple more questions - are you going to have to machine the spring seats at all? Just thinking ahead to when you start checking clearances and spring heights.

What valve seals, retainers and locks are you going to use?

Are those Crane rockers bushed? I have a set of NOS 273 rockers I thought would cool to go nuts with - bushings, modern adjusters etc.

Personally, I'd be interested in seeing how these heads are finished up when you're done with all the machining. I'd really like to see how close you can get things to match up from valve to valve.

I'm of the school of thought that if all the individual parts are made to operate as equally as possible, you will have a better running engine, all things being equal. Stuff like checking spring heights and using shims if necessary, checking the rocker pattern across the valve tip for proper geometry, etc. Takes a lot of effort and time but it does amount to something. Blueprinting is cool!

Sorry for getting slightly off topic and asking about obvious things, but I think these details are relevant to the final product.

It's impressive that you're going to all this effort with lo-po factory iron castings though.
 
Haven't cc'd them yet, going to mill them to 65 cc when finished. Probably take .030 - .040 off to get there.
The spring seats are completely milled down .060 for installed height.

IMG_0386_zps0aae5853.jpg


Using blue viton seals, Comp retainers, 10* Crower locks, and Comp spring seat locators. Easy to see the retainer weight difference between beehive and std springs in the pic.

IMG_0390_zps5c409144.jpg


The valve seat machining is finished to within + or - .003 of target. I use a deck bridge during the seat cutting process. The installed heights are determined by each individual spring's installed pressure, and shimmed accordingly. I use spring seat locators for better stability and durability.

IMG_0392_zpsab58827b.jpg
 
skrews said:
Haven't cc'd them yet, going to mill them to 65 cc when finished. Probably take .030 - .040 off to get there.
The spring seats are completely milled down .060 for installed height.

Using blue viton seals, Comp retainers, 10* Crower locks, and Comp spring seat locators. Easy to see the retainer weight difference between beehive and std springs in the pic.

The valve seat machining is finished to within + or - .003 of target. I use a deck bridge during the seat cutting process. The installed heights are determined by each individual spring's installed pressure, and shimmed accordingly. I use spring seat locators for better stability and durability.
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Thanks for the info. Looking forward to seeing the finished products. Again, not much love out there anymore for small block Mopar factory iron heads. :thumblef:
 
rmchrgr said:
Thanks for the info. Looking forward to seeing the finished products. Again, not much love out there anymore for small block Mopar factory iron heads. :thumblef:
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I know this is a old thread but did you ever use these heads?
 
Nice work Skrews!

I've been a Big-blocks kinda guy since the 80's but a 'bad back' has made me 'see the light' with small-blocks.
Played with 318 (402) Poly's for a while and now got some 340/360's and 318's to build too.
We have all been seduced by aluminum over the years, but a shed full of IRON heads has got me thinking?
I don't have access to a machine shop now, as its closed down due to 'lack of interest' from customers.

So with all your ultra valuable advice and knowledge I will be 'porting crazy' during my Corona isolation.
Home porting with time/effort and little or no machine shop work...

Best wishes from the UK John
 
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Some simple questions for anyone 'in the know'?
Valve choice for J heads?
Tulip or Stainless flatties...
I got Milodon, Ferrea, cheapo chinese and good old 'factory Tulips' as its spring lol.

I can't go to 'all out' portwork, LIKE SKREWS, but how far can you go, around the original guide boss???

Thanks from the Limey
 
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STRorange said:
Some simple questions for anyone 'in the know'?
Valve choice for J heads?
Tulip or Stainless flatties...
I got Milodon, Ferrea, cheapo chinese and good old 'factory Tulips' as its spring lol.

I can't go to 'all out' portwork, LIKE SKREWS, but how far can you go, around the original guide boss???

Thanks from the Limey
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Can't go wrong with Ferrea. Don't use the factory style tulip valves.
 
Many thanx for the reply Skrews!

I only asked about factory 'tulips' as I saw somewhere else that Mopar S/B heads were designed with these specifically in mind?
I don't have a flowbench to find out any data for myself and like most folks, just do 440 yard test runs lol.
Reading this an other very informative threads on 'A-bods', J heads are good and can be great, just don't touch the SSR!
Judging by your extensive guide boss work, it seems you can leave some 'cast-in' metal behind, as long as its a nice shape.

Many thanx again form the Limey
 
STRorange said:
Many thanx for the reply Skrews!

I only asked about factory 'tulips' as I saw somewhere else that Mopar S/B heads were designed with these specifically in mind?
I don't have a flowbench to find out any data for myself and like most folks, just do 440 yard test runs lol.
Reading this an other very informative threads on 'A-bods', J heads are good and can be great, just don't touch the SSR!
Judging by your extensive guide boss work, it seems you can leave some 'cast-in' metal behind, as long as its a nice shape.

Many thanx again form the Limey
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I try and use a tulip valve whenever I can, but not for the reason most people think. The flow won’t be as good with a tulip, but sometimes that’s a good thing.
 
J heads are good and can be great, just don't touch the SSR!
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SB Mopar heads are never great without the short turn being reworked.

The thing is....... where they need work is where the water is.
So it’s often a case of reshaping as much you dare.

That’s been my experience anyway.
 
Hi skrews,
What was the ‘end story’ for these wonderful 308 heads?
Looking to do a 400hp+ 371 cube build with some 72 J heads, but what is actually possible with a 308?

Did someone say 484hp with J’s...:drama:
 
polyjohn said:
Looking to do a 400hp+ 371 cube build with some 72 J heads, but what is actually possible with a 308?
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Totally possible. Should not be a problem at all with ether head. Are you looking for maxims on each head?
 
Many thanx for the reply Rumblefish.
Never seen a set of 308's here in the UK so am very interested in finding out 'more' about them.
I have several sets of 'J' heads in various degrees of porting from Mild to Wild.
Once we return to the track I can find out which ones work the best?

Loved the article by Dulcich on the Edelbrock 'maxxed out' S/B heads but the Hotrod site doesn't work anymore in the UK?

My Moparmate with a 67 Charger, runs a 408ci Hughes engine with Eddy's and we will see where he is at?

I have other Moparmate who will be running a 66 Coronet with a 402ci Poly.

But me, a 371ci LA in my 66 Coronet, don't want to go all stroker with this S/B...:thumbsup:

ps, If I posted this on B-Bods they will all say go 440ci or bigger...:mob:

pps the avatar shows my other Moparmates 512ci in his 66 polara with Eddys, I call it CHEATING...:soapbox:
 
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Your welcome polyjohn. FBBO and many here will always defer to bigger is better which is true in most cases and a easy default setting reply. It is almost to easy to type that in all the time. It is not always so easy to do or afford. The sister site’s most popular engine for the B body platform is a B or RB engine. That’s why it is the default answer. Also, I’m not trying to disrespect or degrade, but I think most there would not know what to do with a small block because it instantly challenges them hard. Not a big deal. No one knows it all.

In working with what you have, it comes down to math. Knowing what your starting with and where you want to go and be standing at, at the end of the day can be a challenge but one in which you just need to overcome and adapt to. It just may have compromises that a larger engine will not have. Which is easily solved with more money, a luxury we all don’t have.

If money was a no option obstacle, then it would be a press of a button for a Ray Barton stroked HEMI with a super charger or twin hair dryers.

The early X, J etc... heads have what you need.
A set bowl ported done right should be enough to run in the 12’s.

I don’t know what is with the HotRod site. I think it sucks and the only way I can find anything is if someone left it here or I saved it. The search engine is ridiculously lame. I actually have much in print saved in a binder. Mostly the MoPar Muscle magazine.
 
Whatever happened to skrews?

My mates just lucked into a cheap Duster for the track.
I would like to do a skrews 'lookalike' 360 'BUDGET-BUILD' lol...
If that don't work I'll get a 440 DOH...:rofl:
 
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