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440 Heads on 383??

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delfinomuro

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Ok guys you might tell me that I'm stupid for asking this question, but I don't know and want the answer so here it goes....

Will it make any performance difference if I put 440 heads on a 383 block?

It's a 66 383 block off of a fury, and the 440 heads are off a charger.

Thanks
 
i would imagine compression would be lower and lose some performance am i right
 
no, they're the same heads



now there's some differences in the years on the heads themselves (open vs closed chambered, valve size, etc), but for all general matters, they're the same head 383 vs 440

Big block heads are referred to by the last 3 numbers of their part number:

if you look at this example, this is referred to as a 452 head

452.jpg


The most common big block heads that seem to pop up:

915's (67 440, closed chambered, can have either a 1.6 or 1.74 exhaust valve)
906's (68-70 B/RB 2.08/1.74)
346 (71-73 B/RB 2.08/1.74), same exhaust port as a 906, but intake port is a little different
452's (76-78 B/RB, 2.08/1.74) Has hardened valve seats, (I've had more sets of 452s than I can remember)



Now that that's out of the way, if the heads on that '66 383 are original, they should be 516's (IIRC, 516 heads don't have freeze plugs on the end), and your guess is as good as mine as to what's on the 440... depending on what ya got, I'd either put a bigger exhaust valve in the 516's or put the heads from the 440 on it.
 
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From 68-70 the same heads were used on 383s and 440s according to a source I read. The part number ended in 906. The difference in earlier heads, I have been told is the valves are bigger on the 440 heads. Do a web search with the question " What does putting 440 heads on a 383 do?". It will give you some hits with more info. Hope that helps.

delfinomuro said:
Ok guys you might tell me that I'm stupid for asking this question, but I don't know and want the answer so here it goes....

Will it make any performance difference if I put 440 heads on a 383 block?

It's a 66 383 block off of a fury, and the 440 heads are off a charger.

Thanks
Click to expand...
 
Depends. A 66 383 will have the older closed chamber heads. What year 440 would the heads come from? 67 heads from a high performance 440 would have bigger valves and exhaust ports. 68 and newer heads would have the bigger valves and ports but larger combustion chambers so would lower the compression. Since you said a Charger, the 440 heads would probably be open chamber heads. http://www.hotrodreference.com/758/big-block-mopar-cylinder-head-casting-numbers/ will give you the data on all the Mopar big block heads.
 
delfinomuro said:
Ok guys you might tell me that I'm stupid for asking this question, but I don't know and want the answer so here it goes....

Will it make any performance difference if I put 440 heads on a 383 block?

It's a 66 383 block off of a fury, and the 440 heads are off a charger.

Thanks
Click to expand...
The Cylinder Heads on the 1966 '383' were {Casting #2406516}, which have valves sizes of 2.08" Intake / 1.60 Exhaust, with a 'closed chamber' combustion chamber {79.5 CC volume from the factory}.

The Intake Ports have a 'flat floor' on the runner side. The Exhaust Ports are tight in the bowl area
and have a 'bump' in the floor area. CFM flow is somewhat restricted with these Cylinder Heads, but with 'work' they can be useful on the street for low RPM Horsepower and Mid-Range Torque.

The 1966 '383' 325 HP 4-Barrel engine came thru with a 10.0-1 Compression Ratio, and the flat-top
pistons are to be set at {-.014"} below the block deck surface.

I'm guessing that you are talking about using the 440 Cylinder Heads {Casting #2843906}, which have valve sizes of 2.08" Intake / 1.74" Exhaust.

These heads were found on both the {1968 thru 1970} '383' and '440' engines.

These heads have very good ports, both in the bowl area and runners, and provide more
CFM flow {+10% Intake Flow and +18% Exhaust Flow} than the earlier '383' Cylinder Heads.

But, they came thru with 'open chamber design' in the combustion chamber, which has a
CC Volume of {88.5} from the factory.

Though these Cylinder Heads can bolt on the 1966 '383' engine, compression will drop almost
a full point {1.0} in a 'straight swap', costing you about {4 to 5%} in Horsepower.

What you gain in 'CFM Flow', you will lose in Compression.

Unless, you have the 440 'open chamber' Cylinder Heads milled.
 
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yeah but a straight even 906 vs 516 swap, even with the loss in compression you'll gain power... that's how crappy the 516 is in stock form
 
What I'd do if I were you, keep the current heads if they really are 516's. Drill out for the bigger exhaust valve and do a porting job on them, you'll notice a big improvement and you won't lose any compression. Did that on my 66-300 w/516's.
 
As 69a100 said. I also did the same to my 66 300 when I first started out in the Hobby. I also used the 516's on my 66 Ply Sat build/383 which turned out to be a nightmare. So I switched to the 440 Source Heads and have not looked back since. The 516's are good heads. Just not as popular as the others as stated. A good closed chambered head that can be tweaked and massaged to perform really well...cr8crshr/Tuck
 
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The factory sales literature said the new Road Runner 383 got 440 heads and cam to make that special engine for the 68 model year. But reality says every big block between 1968 and 1970 got 906 heads. Now, in one case, maybe two, I have seen 915 heads installed originally on a 66 383. It would make sense since the 915 heads came out as the 1.6" EX valve version in 66 for the big Chryslers. The 915 head, and I will say the 906 as well, have the the same ports, which is the best intake port profile out of all the factory heads, including the Max Wedge. The question is how much gain would you see on a street car by swapping from a 516 to a 915 or 906? Even the old MoPar stage IV heads have the flat intake port floor as found on the 516, 346, 452 and they seemed to work. My guess since a street car is rarely operating at peak power you won't see much difference, if any, but your cam selection will make a HUGE difference so in this area you must choose wisely. If you get a good deal on a done set of 906's and they have hard seats installed then throw them on, otherwise do what A100 said and freshen up your 516. Add the right cam, headers with a free flowing dual exhaust and don't look back.
 
Meep-Meep said:
Now, in one case, maybe two, I have seen 915 heads installed originally on a 66 383. It would make sense since the 915 heads came out as the 1.6" EX valve version in 66 for the big Chryslers.
Click to expand...

I wonder? Was this because they ran out of the 516's towards the end of the model year and just starting using the 915's to fill the gap? I know Mopar did goofy stuff like this with other parts during the 60's.
 
That would be my guess. I can't imagine any manufacturing facility throwing something out that was otherwise OK to use. Or on the other hand, keep the line moving. Ford was very good at using up leftovers to the point that many 68 Mustangs came with 289's rather than the new for 68 302. Only the GT didn't get the 289. I've heard reports of 302 heads on 289's, or one 289 head and one 302 head (Ford cast the engine displacement under the valve covers and in the lifter valley of the block so easy to spot). Use it up; wear it out; make it do; or do without.
 
Remember the auto strike in the late 60's when Ford tried to keep the line rolling using management for line workers?? I'm thinking the strike was in mid 66 or so? A buddy bought a 66 Mustang that was a 6 banger but it had all V8 underpinnings including 5 lug wheels! It even sit higher than normal....
 
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Yes, I heard about the strike. One Ford guy commented that my car was built before the strike because it had all the A pillar pads and knee pad. Apparently during the strike much of the equipment didn't make it on the cars, or as you pointed out, the wrong equipment! Now who ordered a 390 GT and got a 428 or 427 in it's place??? Wouldn't that be cool!?
 
Thanks guys!!! Sounds like it will be better if I keep my original heads and just suit them up. The guy is selling me the heads and intake off of a 440 for $60, that's why I asked.
 
I would concur buying them just because they're 60 bucks. But wouldn't you want a smaller head size for more compression. I guess it all just depends on what your looking to get out of it. Let us know how it turns out.
 
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