It begins again - 512 Stroker

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Imo, if you’re planning on putting any real mileage on the motor, especially with a cam that requires higher spring loads than the OE springs..... just put the hardened exhaust seats in now.
There are no factory Mopar iron heads immune to exhaust seat recession.

My other advice is...... since you won’t have any quench....... be conservative with the CR.

Oh, and I don’t think there’s any danger of making 600hp with a 512 using template ported stock heads with a 509 cam.

Well.......it wouldn’t make that here anyway.
 
Once upon a time we ran a 7.85:1 compression 440 on the dyno with a 108 LSA 509 cam. 850 cfm Mighty Demon, 2" Super Sucker spacer, M1 single plane, 516 factory iron heads flowing 250 cfm @ .500" lift and our dyno headers. 460 TQ @ 4,200 rpm and 449 HP @ 5,300 rpm. The 600 HP 452 heads were flowing in the 300 cfm range @ .600"
 
The 600 HP 452 heads were flowing in the 300 cfm range @ .600"
Click to expand...

300cfm from 452’s is a weeee bit more involved that following the MP templates.

I had someone send me some stage V‘s
that they had template ported using the stage V specific templates, then finished off the rest of the ports with some sanding roll work.
Flowed in the 240’s.

They sure “looked” like they would have followed more than that.

Don’t forget...... the instructions with the templates warn against touching the short turn........ so if you really follow the instructions to the letter....... you’re only going to get so much flow.
 
Last time I had a set of iron heads built for an engine they cost more than $2000. Hard seats, new valves, new springs and seals, new guides, valve job, surfacing, etc. This was before any porting. Cast iron heads are a waste of money for the average guy.
 
We dyno tested a "reproduction" type 440 this summer where the owner had spent a chunk of money rebuilding the original cast iron heads. Once the engine was on the dyno one of his numbers matching heads sprung a leak. The heads had been completely rebuilt and had cost more than a new set of aluminum heads but that didn't keep the 50 year old cast iron from cracking. He had to go find another correct casting and have all the work redone.
 
PRH said:
300cfm from 452’s is a weeee bit more involved that following the MP templates.

I had someone send me some stage V‘s
that they had template ported using the stage V specific templates, then finished off the rest of the ports with some sanding roll work.
Flowed in the 240’s.

They sure “looked” like they would have followed more than that.

Don’t forget...... the instructions with the templates warn against touching the short turn........ so if you really follow the instructions to the letter....... you’re only going to get so much flow.
Click to expand...

Correct........

The 452's were the first set of heads my son and I used for a performance build. He asked for us to build a performance engine together after he found an article in Dec 1982 Popular Hot Rodding that featured a 440 that his grandpa (my dad of course) had built. He wanted to do the same thing. So I told him we needed cylinder heads to proceed.

He spent somewhere between 9-12 months, a full pallet of cut up, drilled to swiss cheese and band-sawed in half iron cylinder heads, of which, three were Stage V heads, one to practice on and two to use. He destroyed all three Stage V's.

The flow bench he used was some 4 miles from the porting room (a single car garage on 4 acres), so it really was a herculean effort.

Eventually he brought me the 452's and said, "What about these?" Well, 588 tq and 621 hp.

The project evolved until the little 451 stroker made 787 HP on 91 octane pump gas with Edelbrock 84cc 440 RPM cylinder heads. His porting of course.
 
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IQ52 said:
Once upon a time we ran a 7.85:1 compression 440 on the dyno with a 108 LSA 509 cam. 850 cfm Mighty Demon, 2" Super Sucker spacer, M1 single plane, 516 factory iron heads flowing 250 cfm @ .500" lift and our dyno headers. 460 TQ @ 4,200 rpm and 449 HP @ 5,300 rpm. The 600 HP 452 heads were flowing in the 300 cfm range @ .600"
Click to expand...

Yeah but all the forum gurus said that motor would be sluggish and unresponsive and slow to rev. What a piece of crap it had to be then. <rolls eyes>
 
IQ52 said:
Correct........

The 452's were the first set of heads my son and I used for a performance build. He asked for us to build a performance engine together after he found an article in Dec 1982 Popular Hot Rodding that featured a 440 that his grandpa (my dad of course) had built. He wanted to do the same thing. So I told him we needed cylinder heads to proceed.

He spent somewhere between 9-12 months, a full pallet of cut up, drilled to swiss cheese and band-sawed in half iron cylinder heads, of which, three were Stage V heads, one to practice on and two to use. He destroyed all three Stage V's.

The flow bench he used was some 4 miles from the porting room (a single car garage on 4 acres), so it really was a herculean effort.

Eventually he brought me the 452's and said, "What about these?" Well, 588 tq and 621 hp.

The project evolved until the little 451 stroker made 787 HP on 91 octane pump gas with Edelbrock 84cc 440 RPM cylinder heads. His porting of course.
Click to expand...

Was that the chassis dyno run in the Duster?
 
Yeh......a weeee bit more than template porting.

I just finished up a set of J heads.
Some people just gotta have the old iron.

I’ve actually done quite a few factory iron head jobs(not just Mopar) in the last year or so.
A bit of a bump in that type of work from what’s been the norm over the last few years.

It’s pretty rare that I get to work on a set of old factory iron heads that haven’t been previously molested...... and sometimes that previous poorly executed work can take some time to undo....... and time is money.
 
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RustyRatRod said:
Yeah but all the forum gurus said that motor would be sluggish and unresponsive and slow to rev. What a piece of crap it had to be then. <rolls eyes>
Click to expand...

We put the 440 in a '72 Satellite with 2.46 gears. It drove mellow around town like a grandma's car. However on the highway it was getting warmed up around 90 mph. It made 450+ lb-ft of torque from 3,200-5,200 rpm. The factory 318 suspension was somewhat loose, so that was plenty fast enough in that car.

The 451 with 906 heads did 554 RWHP in a '71 Road Runner. Later, with cam change.........on engine dyno 694 hp @ 9.5:1 compresssion on 91 octane.

The '72 Demon, with a Duster front end, had a 500" wedge with Edelbrock Victor cylinder heads and made 696 RWHP.

 
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IQ52 said:
We put the 440 in a '72 Satellite with 2.46 gears. It drove mellow around town like a grandma's car. However on the highway it was getting warmed up around 90 mph. It made 450+ lb-ft of torque from 3,200-5,200 rpm. The factory 318 suspension was somewhat loose, so that was plenty fast enough in that car.

The 451 with 906 heads did 554 RWHP in a '71 Road Runner.

The '72 Demon, with a Duster front end, had a 500" wedge with Edelbrock Victor cylinder heads and made 696 RWHP.

Click to expand...


The Demon. yeah that's the one I was thinkin about. Another of them dang non responsive Laroy builds. lol
 
PRH said:
Yeh......a weeee bit more than template porting.

I just finished up a set of J heads.
Some people just gotta have the old iron.

I’ve actually done quite a few factory iron head jobs(not just Mopar) in the last year or so.
A bit of a bump in that type of work from what’s been the norm over the last few years.

It’s pretty rare that I get to work on a set of old factory iron heads that haven’t been previously molested...... and sometimes that previous poorly executed work can take some time to undo....... and time is money.
Click to expand...

The last set of heads we did were J's for a family member, he had to have iron! Been turning down cylinder head and engine builds all year.

These projects are more fun. My son takes shed antlers and makes steel skulls for them. And will make copies of the antlers............both out of exhaust tubing.

BIG SHEDS 010.JPG
 
RustyRatRod said:
The Demon. yeah that's the one I was thinkin about. Another of them dang non responsive Laroy builds. lol
Click to expand...

Yep, unfortunately we have really stunk things up.

Looking back at it, the only real fun was building things for ourselves.
 
IQ52 said:
Yep, unfortunately we have really stunk things up.

Looking back at it, the only real fun was building things for ourselves.
Click to expand...

I would love to see yall do a slant six.
 
RustyRatRod said:
I would love to see yall do a slant six.
Click to expand...
We have a prior commitment with a cash deposit to do one. So it will happen. I am moving the engine shop back to my house so Cody can have the run of the shop for his art and other welding projects.
 
IQ52 said:
We have a prior commitment with a cash deposit to do one. So it will happen. I am moving the engine shop back to my house so Cody can have the run of the shop for his art and other welding projects.
Click to expand...

I sure hope you plan on posting about it. I would love to see it.
 
IQ52 said:
Correct........

The 452's were the first set of heads my son and I used for a performance build. He asked for us to build a performance engine together after he found an article in Dec 1982 Popular Hot Rodding that featured a 440 that his grandpa (my dad of course) had built. He wanted to do the same thing. So I told him we needed cylinder heads to proceed.

He spent somewhere between 9-12 months, a full pallet of cut up, drilled to swiss cheese and band-sawed in half iron cylinder heads, of which, three were Stage V heads, one to practice on and two to use. He destroyed all three Stage V's.

The flow bench he used was some 4 miles from the porting room (a single car garage on 4 acres), so it really was a herculean effort.

Eventually he brought me the 452's and said, "What about these?" Well, 588 tq and 621 hp.

The project evolved until the little 451 stroker made 787 HP on 91 octane pump gas with Edelbrock 84cc 440 RPM cylinder heads. His porting of course.
Click to expand...

Not everyone is able to do this tho .
 
famous bob said:
Not everyone is able to do this tho .
Click to expand...

True, but jim is accurate as one can be.

When he set me up with my combo he knew exactly where it would end up before it even went together and the results far surpassed my expectations. There are many ways to skin a cat and he may have tried most of them.
 
roccodart440 said:
True, but jim is accurate as one can be.

When he set me up with my combo he knew exactly where it would end up before it even went together and the results far surpassed my expectations. There are many ways to skin a cat and he may have tried most of them.
Click to expand...

Sure sounds like it .
 
AndyF said:
Last time I had a set of iron heads built for an engine they cost more than $2000. Hard seats, new valves, new springs and seals, new guides, valve job, surfacing, etc. This was before any porting. Cast iron heads are a waste of money for the average guy.
Click to expand...

It’s usually closer to $1500 here to refurbish a set of factory BB heads as you described........ all new parts, hardened ex seats, SS valves, performance springs, etc....... if starting out with a pair of castings that don’t have too many surprises from previous rebuilds.
That gets you to the point where you’re ready to start porting.
And the price could easily be more for a high effort set of heads that’s going to need premium parts like roller springs, severe duty valves, titanium retainers, etc...... the type of heads that would get fairly heavy porting for use in a FAST type of application.

Refurbished, as described above, bowls blended, port openings squared up, pinch area tweaked........ you’ll still have more into them than a set of Stealths....... even after the Stealths have been prepped.

The only way the stock stuff makes sense is for guys like the OP who wanna do some tinkering.
Or if you find a nice set of clean low milage cores that can get away without seats, guides, valves, etc.
 
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I recently came across a set of virgin 906 heads. They had never been apart so nothing ruined by an over eager machinist. First set like that I've seen in a long time. I have no use for them but figured I'd put them on the shelf in case I ever came across someone who needed a nice set of cores for a FAST project or something similar.
 
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