340 X heads advice

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Funny how some people are saying "with the X or letter heads or LMNOP heads" ...that if you started bare "you're going to have a ton of money in them by time you're done" Really? It's all relative...come on already.You have to buy the valves,springs etc ANYWAYS, REGARDLESS, PERIOD. Wow...like WELCOME TO BUILDING CYLINDER HEADS....Pretty dumb to be including that in an arguement. Oh yeah
...and uh...please, can you not tell me where you bought your heads.... cause it feels too much like another sales pitch.
Best of luck OP, cost and results will vary.
This advice will self destruct in T minus 5...4...3....2... lol
 
67autocross said:
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Damn....looks like all the "head porter" did was blew the dust out of them with air hose ..lol
Quickest port job in the history of mankind.
With results like those...I bet I spend more time wiping after a dump for crying out loud.
Too bad you weren't close, I'd have done more for an 18 pack in porting/results...and right before your eyes to see.
 
Wyrmrider said:
DIY
Bowl blend
good start
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Hey... he did make 8-10 more average hp ability.lol
If he did that himself, hes fine. He didn't 'wreck it ralph' like another did ...in another thread. Dont like seeing people get screwed is all.
 
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I'd give him the clap
no fooling with the short side except to clean up casting flash and no wasting time on the intake faces which are not a problem
no fountains
he's golden
I've let guys do a DIY blend after I did a multi angle valve job and throat opening on the SERDI
I have/ had all the safety equipment, eye protection, dust removal, lighting
give them an old head to practice on
some eventually got hired
I used to charge a bunch to do Iron
 
Wyrmrider said:
I'd give him the clap
no fooling with the short side except to clean up casting flash and no wasting time on the intake faces which are not a problem
no fountains
he's golden
I've let guys do a DIY blend after I did a multi angle valve job and throat opening on the SERDI
I have/ had all the safety equipment, eye protection, dust removal, lighting
give them an old head to practice on
some eventually got hired
I used to charge a bunch to do Iron
Click to expand...
I just followed the advice of the machine shop owner on how to clean up the bowls and back side of the seats. He had me do a little off the area where the push rod runs.
I was more worried about hitting a valve job than anything else but I wanted to do a before/after comparison.
Keep in mind these are going on a 375hp 87 Octane 360.
 
Well....... I passed on the bare 340 X heads. I am thinking in the ideas of either aluminum, or a new set of reman X heads from Hensley Performance, in Knoxvlle, or a set of Those mentioned EQ heads.
The block is a 1975 standard bore, That was built at the ole "Quaden Dodge" in SE Wis, some time ago. I removed the cam, and lifters. There is hardly any slack in the double roller chain. Its got an "M" on it, I take for Melling. Lifters and cam are very clean, as is inside of block. The cam is an "Erson" Hi Flow B115S1 07 1H 108 KD. These are all the numbers on the end of it. I havnt been able to find out anything about it, at Erson.
I have 4 other cams in my stash that I can use, one Jegs, one Summit, two Comp cams, one of which is a solid lifter version.
I was looking at the EQ heads, but I don't fully understand what parts from my LA head parts I can use. I have new rocker shafts, trick flow springs, and a set of comp cam springs also, some other stuff.
This is new territory for me.
I appreciate all the help, and advise.

Dave

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Low compression pistons there. The heads you list as candidate have a bit over 1 full point in compression variation... as saked before: watcha doing with this engine? The head selection may vary, and the cam selection will vary, depending on the answer...
 
autocross that's what I suspected you had done- good move
on the heads are those stock low comp 360 or rebuilder "compensated" ones
post the deck clearance please
 
50 down is quite high for a 360
a search gives
Where Can One Find Published Factory 360 Piston Compression Height?
and
Stock 360 deck height

I've see 1.687 to give 0 deck but you can calculate yourself
deck height (say 9.6 for a non magnum) - (1/2 the stroke + rod length + piston compression height)
get really fussy rods may have been cut when rebuilt and block decked to a different height - still .050 with stock pistons is short- good for you
remember 71 360s had flat top pistons
as NM is hinting choosing heads that vary by a point in compression is not the right thing to do till you figure out what your "fill" volume at TDC is
not hard to do with some coloured alcohol and a big syringe, flat piece of plastic with a hole and seal up the piston with some grease
then you can play with head cc's and gasket cc's and get dialed in
the question of usage
and the rest of the build also get factored in
look down for the only 360 line here
Deck Height and Compression Distance Data
 
What I really like is those lifter bores.
Have a custom street solid roller ground for that thing. You can ball hard and still close that mfr at 46 or so degrees. Nice manners and torque out the wazoo.
 
MOPAROFFICIAL said:
Funny how some people are saying "with the X or letter heads or LMNOP heads" ...that if you started bare "you're going to have a ton of money in them by time you're done" Really? It's all relative...come on already.You have to buy the valves,springs etc ANYWAYS, REGARDLESS, PERIOD. Wow...like WELCOME TO BUILDING CYLINDER HEADS....Pretty dumb to be including that in an arguement. Oh yeah
...and uh...please, can you not tell me where you bought your heads.... cause it feels too much like another sales pitch.
Best of luck OP, cost and results will vary.
This advice will self destruct in T minus 5...4...3....2... lol
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You're right. It's not like he wasn't gonna replace all that stuff anyway. That said, I think sometimes you're like I am. I think you forget all the stuff you can do and your own resources. Ain't everybody got a flow bench and know how to port heads. Just like with me ain't everybody knows how do do all the stuff I can do. Sometimes I forget that, I know. It's just stuff we take for granted sometimes.

That said, if someone cannot "do stuff" at home, it might be a better deal to start with "some kinda" new castings. After all, they ARE new and not 50 years old. While you and I might can make something outta some "old junk", not everybody can.

And you know me, I'm all about makin old stuff good again. It might not save money every time, but it sure feels good.
 
Wyrmrider said:
50 down is quite high for a 360
a search gives
Where Can One Find Published Factory 360 Piston Compression Height?
and
Stock 360 deck height

I've see 1.687 to give 0 deck but you can calculate yourself
deck height (say 9.6 for a non magnum) - (1/2 the stroke + rod length + piston compression height)
get really fussy rods may have been cut when rebuilt and block decked to a different height - still .050 with stock pistons is short- good for you
remember 71 360s had flat top pistons
as NM is hinting choosing heads that vary by a point in compression is not the right thing to do till you figure out what your "fill" volume at TDC is
not hard to do with some coloured alcohol and a big syringe, flat piece of plastic with a hole and seal up the piston with some grease
then you can play with head cc's and gasket cc's and get dialed in
the question of usage
and the rest of the build also get factored in
look down for the only 360 line here
Deck Height and Compression Distance Data
Click to expand...
The original factory pistons that came in my magnum were around 50 down the hole, the rebuilder pistons would have been down further so I had the block decked to basically get it back to stock. The idea of my build was to do a replica of a factory bottom end with good heads and a cam.

Mild 360 Magnum Build
 
You can't go by the stock Magnums.... The Magnum deck is nominally higher than the LA deck by .015". And with compression height differences, the pistons in a '75 LA would nominally be down around .110" from the deck.

And, those look like the even lower compression truck pistons with that particular dish. Around 6 cc's in those piston dishes alone. Add in some large chamber heads, and the static CR would be around 7.6.....
 
The J heads I had done a few years ago cost $718.00 to do. New stainless valves, K Motion springs, Isky retainers, bronze guides, 5 angle grind with pocket porting and minor port match, angle milled.

My son had his 993 Chevy heads done at the same time...$6.00 cheaper.
 
what NM said about dish- there are a couple of different dishes which is why I recommended measuring
Most I've seen have been over 100 down
when NM says 7.76 he is speaking of typical 100 down not .050 (the way I read his post- I've been wrong B 4)
do not confuse Magnum calculations with LA blocks and heads
 
Typical thread for what should I do for cylinder heads. If you can do the work on your own stuff, have at it. If you need to go to a shop and have the guides, surface, tank, valve job done along with buying valvetrain/seals, expect to have $700ish in that before you get to the cost of the heads. JMO, that's a lot of money in a stock set of heads.

Find a discount code and some of the aluminum variant are really not that much more than a set of done iron heads.

Pick your parts, pay your money
 
crackedback said:
Typical thread for what should I do for cylinder heads. If you can do the work on your own stuff, have at it. If you need to go to a shop and have the guides, surface, tank, valve job done along with buying valvetrain/seals, expect to have $700ish in that before you get to the cost of the heads. JMO, that's a lot of money in a stock set of heads.

Find a discount code and some of the aluminum variant are really not that much more than a set of done iron heads.

Pick your parts, pay your money
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So true, I have went both ways.
The only way that I will even thinking about iron head valve job is if they are a complete head to start with.
I actually am using iron “J” heads on my current build, but I had them and picked them up cheap in a parts lot buy out.
To go looking for a set, I would just grab some newer cast or aluminum head and be done with it. Old heads are a gamble, I have a few sets of cracked to hell iron heads, ironic thing is every cracked LA head I have, had been previously ported.
I have a set of “u” heads that were cracked on 7 of 8 cylinders. Most had multiple cracks on each cylinder.
 
Honestly I'd sooner have tried and true Mopar iron than any import head. They might just last another 40 years.
 
gtsdude said:
It has been a while since I had any machine work done, but in my area I bet you would have right around $1k in those heads to do a total rebuild with good parts, ready to bolt on and go, not including cost of the heads themselves, and that is if they are still good and able to be rebuilt.
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That’s about what it would cost here as well.

It’s really easy to end up with a set of reconditioned castings that have new “everything” that cost $1k........before any porting is done.

I love it when those jobs come thru the door, but it’s pretty much only for an application where oe heads have to used, or a resto type job.
Not to mention that it's very unlikely someone hasn't worked on them before, since they're all getting into that 50 year old range.

Bang for the buck, hard to beat a set of Speedmasters for about a grand.

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Thank you all for the repies. They give me something to bang around in my head.
PRH..... thanks for the before/after pics.

Dave
 
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