To quench or no quench

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It has been sitting together since 2012. I am going to take it apart to make sure everything is lubed up good. So the is options. Kim
 
Sealed power/ speed pro. 2332P

1C98A4A4-E308-4AC4-B12B-42982258E131.jpeg
 
Those are super thick.
Just have them milled off to get them to be zero deck....... then run the closed chamber heads.

A mill, a piston vice, and a big fly cutter.

Or better yet, a piston vice mounted in a head surfacer(depends on what you have for a piston vice and the head surfacer though).

That’s what I’d do.
 
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Well, that’s a different conversation.

If you’re going to use stock heads, then no rework is necessary.

If I had my choice, I’d use unported closed chamber aluminum heads with the valve job fixed and a minor bowl blend, and the pistons set up for zero deck.
 
That’s what I was thinking about using the as cast alum heads but he already has these CNC heads. Milking the pistons may be the best option. The J heads do have hardened ex seats. Thanks. Kim
 
What PRH said
and the better heads will help - not ever wasted not like Boss fords where they get TOO BIG
you can use less cam or not
lets figure your new compression with 0 deck flat tops with 5 cc valve reliefs and a .028-.040 gasket and see where we're at compression wise
 
The down side to the cnc heads in that particular application is, the low/mid-lift flow for those heads, as they come from SM, just isn’t very good.
Combine that with a cam that doesn’t have much lift, ports that are much bigger than factory heads, and a motor that isn’t very big...... and I don’t see how you’re ever going to generate enough velocity in the ports to get really effective cylinder filling.

Up thru .500 lift, it’s pretty easy to outflow the cnc SM heads with heads that have smaller runners.

Bowl blended J head vs ootb SM CNC:
Lift———J/SM
.100—— 67/63
.200——134/127
.300——190/167
.400——236/209
.450——250/228
.500——253/247

Which do think would be better on a 340 with a .470 lift 224@.050 hyd cam?
Even if you were down 10cfm from those numbers in the .300-.500 range with the J head, it’s still a win.
 
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did not realize the sm were that bad down low/
what about unported or ported differently?
otherwise what works if starting from scratch?
308, magnum, EQ
most of the builds we did for motorhomes were stock heads 30 degree seats on the serdi 'with a bowl blend
that seemed to be the most cost effective combination
I don't feel so bad
thanks for posting
 
As I already said......my “preference” would be to use unported closed chamber heads with a decent valve job and a quick bowl blend...... and then run the pistons at real close to zero deck.
I would think one would be able to get the numbers very close to(or perhaps better than) some reworked 2.02 valve stock heads....... for a lot less effort.

It’s just $$$, and if the owner wants that type of combo enough to pay for it.

How much difference would there really be between using some reworked stock heads, unported(but prepped) SM’s, or the CNC SM’s on a combo as mild as that?
There’s only one way to know for sure....... and I don’t see that happening.
So, it’ll come down to one choice..... then iiwii.

The flow numbers I posted for the J head were some pretty nicely done heads, and wouldn’t be representative of what you’d get out of heads with a minimalist “bowl blend”.
That would be more like 215-220cfm @.450 lift.

Typical stock 2.02 head is right around 200.
 
We don't know of the OP's friend's X head are ported or not. So could be a lot of extra cost there and he has the CNC SM's. Put on a .075" thick head Cometic head gaskets (or mill the pistons and use a Felpro 1008) and static CR will be in the 9.9-10.0 range either way, with a good quench/squish gap either way. Slightly better SCR than a stock 340, FWIW.

DCR will be round 8 with the cam at and ICL of 106. Ought to be a piece of cake to tune to stay out of detonation with those closed chamber, AL heads. As stated, engine is for the street and will never be raced.

IMHO the right path is use the heads he has to not put much more $$ into it and stop the friend's head from hurting anymore LOL. Seems like a case of 'better is the enemy of good enough' for a simple street engine that will be lots so fun to drive as it sets right now.
 
The 2.02, true factory 2.02 j heads I've flowed have all been better than 210cfm, usually around the 215-220 area.
But that doesnt mean there arent a ton out there that flowed less.
If I were to get paid what seemed fair for the amount of time and careful work I put into transforming a set of production smog 'nothing heads' into ootb aluminum head destroyers...
They would cost the same. Prices have dropped so much on Chinese aluminum heads meanwhile the parts haven't and have gone up in most cases 10-40 dollars.
100-150.00 for cores ..used to be 80.00
150.00-220.00 in valves/hardware 'talking stainless budget kit stuff" works fine.
400.00 machine work ,seats,seals,guides,surface etc
And then me and my month or so of about 4 -5 trips to the bench per port getting them dialed. Surely I could fly through them in a week, with no day job, just as I could accomplish having burs bite and putting holes in the head.. I used to do a 250 dollar special, gasket match and bowl blend with just a light evening of the as cast short side...yield about 20 cfm. I do the 318 heads for 250.00 still, they are easily repeatable and take lil time in comparison.
I've had people bring me cylinder heads they had just enough good machine work done to them that it only took me 15 minutes to have them flowing mid-high 240's cfm. Some days it seems easy and I'm very proud... other days I feel very under paid and punished..lol... wonder how much more do I have to dig to get there.
In regards to iron 360 heads.
 
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The J heads are 2.02 intakes. They came off of a 70 or 71 340. There is hardened ex seats installed. I believe just a regular run of the mill valve job. I’ll be getting to it in the next couple of weeks. No porting, not even gasket matched. Thanks. Kim
 
On my bench(the only numbers I care about), it’s a very rare stock J head that flows in the 215 range.
It’s not never...... but very rare for me to see that.
X heads do it, but they are absolutely superior to J heads in terms of ootb flow.

I had one set of factory J’s here, off the same motor.
One head flowed 214...... the other 195.
I’ve tested a few pretty pristine T/A heads..... stock valves and VJ......flowed right around 200.

Ootb unported SM Head flows 250.
Like the heads PBR bought for $450 delivered.

I couldn’t even come close to refurbishing a set of stock heads, and then duplicating that level of flow for what a set of assembled & prepped SM heads would cost.

Even without the heads being on sale, you can have the bare heads and a set of stainless valves delivered to your door for under $800.
Another $200-250 for the remaining parts, $400 labor..... you’re at $1450 prepped and ready to go.

I couldn’t get a set of J’s done, (oven cleaned, magged, all new guides, ex seats installed, machined for posi seals and dual springs, flat milled, and then ported enough to achieve 240+cfm, along with all new parts) cleaned, assembled and ready to bolt on for the same money.

I suppose what one pays will depend on who they’re doing business with...... but at my shop..... prepped SM’s would be less $$$ than “equivalent” J’s.
And if the SM’s were on sale...... then the price spread just grows.
 
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PRH said:
On my bench(the only numbers I care about), it’s a very rare stock J head that flows in the 215 range.
It’s not never...... but very rare for me to see that.
X heads do it, but they are absolutely superior to J heads in terms of ootb flow.

I had one set of factory J’s here, off the same motor.
One head flowed 214...... the other 195.
I’ve tested a few pretty pristine T/A heads..... stock valves and VJ......flowed right around 200.

Ootb unported SM Head flows 250.
Like the heads PBR bought for $450 delivered.

I couldn’t even come close to refurbishing a set of stock heads, and then duplicating that level of flow for what a set of assembled & prepped SM heads would cost.

Even without the heads being on sale, you can have the bare heads and a set of stainless valves delivered to your door for under $800.
Another $200-250 for the remaining parts, $400 labor..... you’re at $1450 prepped and ready to go.

I couldn’t get a set of J’s done, (oven cleaned, magged, all new guides, ex seats installed, machined for posi seals and dual springs, flat milled, and then ported enough to achieve 240+cfm, along with all new parts) cleaned, assembled and ready to bolt on for the same money.

I suppose what one pays will depend on who they’re doing business with...... but at my shop..... prepped SM’s would be less $$$ than “equivalent” J’s.
And if the SM’s were on sale...... then the price spread just grows.
Click to expand...

And there is where the customer makes their decision on what shop to use.
Its all money. Some areas charge A TON more because they are one of few or the only shop around..others because they are next to the race track $ and then the ones that corner a specific market of mopar guys.lol
Options are good.
Not all options are created equal and prices will vary.
 
100-150.00 for cores ..used to be 80.00
150.00-220.00 in valves/hardware 'talking stainless budget kit stuff" works fine.
400.00 machine work ,seats,seals,guides,surface etc
And then me and my month or so of about 4 -5 trips to the bench per port getting them dialed.
Click to expand...

What I see there is $770, plus porting.

So, you’re saying you’re going to port the heads over the course of 4-5 weeks, and flow each port 4-5 times......for $680?

The prepped, ready to install Chinese heads are $1450......and you said you’d do your job for the same price?

That would be a huge “no thank you” from me.
 
PRH said:
What I see there is $770, plus porting.

So, you’re saying you’re going to port the heads over the course of 4-5 weeks, and flow each port 4-5 times......for $680?

The prepped, ready to install Chinese heads are $1450......and you said you’d do your job for the same price?

That would be a huge “no thank you” from me.
Click to expand...

You've stated you have no interest in performing the amount of work it takes on this old **** 2 or 3 times. That is your prerogative, I dont hold it against you. I'm sure you would be losing money in a high volume shop situation.
Not gonna long wind this, its thread graffiti after a while.

Though as a side note...Who else likes reading posts that say how it's too much work to make a factory head perform and to go buy aftermarket heads....aaaand then in another thread read them saying how easy they can get those big numbers cuz they're so fucktacularily good...cracks me up how it always turns to piss.
 
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No pissing contest.......I’m simply asking if you’d really do all that work for $680.
(Finished, ready to bolt on heads, flowing 250-ish for $1450)

If so, maybe you’ll get a nice influx of work.

I doubt there would be many Mopar savvy shops in the country willing to do it for that price, but I could be wrong.

But to be clear, my position isn’t that I’m not interested in doing the work....... it’s that if someone is looking for some heads that have those kinds of flow numbers...... they’re going to spend more reworking factory heads than if they had started with aftermarket heads....... if they’re shopping with me.
 
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