Iron head test starting on '78 440.

[IQ52]

This sounds like an event I would love to attend. Will this be Sat and Sunday? Sept 14 and 15? Will it go into Monday? What about starting Friday the 13th? Lol. A 2 or3 day event would make it worth the trip up there from Denver. Ok Thanks for offering some thing like this to the Mopar Guys.

The "event" will be one day only, Saturday the 14th. We don't run on Sunday. The engine will most likely be on the dyno for weeks to try everything we want to.

 

[krowbar]

516 heads are the old closed chamber design with a flat "old style" intake port. Valves are 2.08" / 1.60"

915 heads have the same chamber as the 516 but a much improved intake port. Valves are 2.08" / 1.60" and 2.08" / 1.74" for HP. As far as I understand it, the 915 head port design was changed based I'm recommendations of Harry Weslake (as in Gurney/Weslake fame).

906 heads have an open chamber just like you see on all the 70's vintage heads but the same intake port as the 915. Valves are all 2.08" / 1.74".

For some reason, and I have to believe it's emissions related somehow, the 346 and 452 went back to the flat intake port floor just like the 516's. On a dry flow bench these heads may all flow equally, but under actual conditions (wet flow) the 915 and 906 might have an advantage over all the other iron heads.

How many different heads are there for big blocks? Anybody got a link? I'm hungry for info.

 

[67Satty]

This link covers most all the post-1967 big block Mopar heads with charts for flow numbers. Interestingly, it shows all the later open chamber ones flowing pretty equally on the intake. The all look equally bad on paper compared to the aluminum offerings!

http://www.moparmusclemagazine.com/techarticles/5115_cylinder_heads/

 

[kdtjb]

Jim, this sounds like a day not to miss. Just how many burgers you got? Wimpy.

 

[IQ52]

Jim, this sounds like a day not to miss. Just how many burgers you got? Wimpy.

They'll be enough I suspect, and you won't have to promise to pay for them the following Tuesday.....Popeye

Now if I can get Cody back to the shop and on the 440. He put some Hemi exhaust valves and Chevy intake valves in a 12 valve Cummins, then ported the head. He's off puttin' that engine together for the owner. Fired it last night and they are workin' on some fuel issues, but he says it builds boost instantly.

Okay, he's back.

My-oh-my, I quess that truck is something now, but Cody has now taken off on some kinda date with his wife.

What gives with this love your wife crap? Maybe just because she's a nice lady and he really likes her?

 

[kdtjb]

Well right now I'm planing on coming your way. If there is any thing I can help you with, let me know. I will keep you posted. If the weather's nice, maybe we can bring a car or two from the Chicken Coop. Kent.

 

[Budnicks]

They'll be enough I suspect, and you won't have to promise to pay for them the following Tuesday.....Popeye

Now if I can get Cody back to the shop and on the 440. He put some Hemi exhaust valves and Chevy intake valves in a 12 valve Cummins, then ported the head. He's off puttin' that engine together for the owner. Fired it last night and they are workin' on some fuel issues, but he says it builds boost instantly.

Okay, he's back.

My-oh-my, I quess that truck is something now, but Cody has now taken off on some kinda date with his wife.

What gives with this love your wife crap? Maybe just because she's a nice lady and he really likes her?

Darn kids...LOL...

 

[IQ52]

So never trust..............oh, I mean verify everything you are told by someone else.

Turns out we have a .040" over 1972 440 with a cast crank and 906 heads. First 1972 440 I have seen with a cast crank. Before I get any lectures, of course 1972 440s didn't come from the factory with 906 heads. And yes, the exhaust valves are disappearing down into the exhaust bowls because there are no hardened seats installed.

The pistons are .165" down in the bore, so even with the 516 heads that I just cc'd at 81 cc's, we'll have no more than 7.998:1 compression. Okay lets call it 8:1. It looks like we can run the entire test on 85 octane. Seems it has been rebuilt before and installed into a 1978 New Yorker.

 

[Budnicks]

hummm the plot thickens, but still a good subject thou...

 

[Meep-Meep]

Did you CC the cylinder volume with the piston at TDC? Just curious if your late model 440 has the huge bore chamfer like my late model 440. If so that is good for a few cc's that won't show up doing the simple calculation, and as you know will drop your compression to even lower numbers. Perhaps 7.668:1? Should I send my Pro Charger along with the heads? I'm fresh out of 8-71 blowers!

 

[Cranky]

I've had more than my share of low compression big blocks ping and diesel their guts out but on the other hand, I've had a couple that actually ran pretty good without the ping issues so long as the temps were kept down to 185 or less.....

 

[IQ52]

Hey, when you do a 4/7 firing order swap, does that mean you swap the #4 & #7 pistons too?

 

[451Mopar]

I wish I had the time off to check it out. Sounds like alot of fun (and work.)

 

[IQ52]

Did you CC the cylinder volume with the piston at TDC? Just curious if your late model 440 has the huge bore chamfer like my late model 440. If so that is good for a few cc's that won't show up doing the simple calculation, and as you know will drop your compression to even lower numbers. Perhaps 7.668:1? Should I send my Pro Charger along with the heads? I'm fresh out of 8-71 blowers!

The only time I do a .500" down fill volume is when I have a pop up or a valve relief notched piston. These are of course flat tops with no valve relief notches. They have a nice conservative chamfer at the top of the bore.

Man they did a lot of hammering when rebuilding these 906 heads. The valve tips have hammer marks on the edge of the tip and the stems have retainer indentations from when they struck the retainer with a hammer to break the locks loose. Had to file the valve tips to get them to slide through the valve guides. Knotheads.

 

[Meep-Meep]

I have seen exactly what you are talking about regarding hammer marks. Also the keeper grooves so worn that they produce a huge burr. NO fun.

The guy that I'm building the 451 for gave the OK for me to send you the pocket ported 906's so you should be expecting them soon.

 

[IQ52]

Well, we found the 516 heads we had used a long time ago. They first went on a 413 with 11:1 Max Wedge pistons. That engine went into 2 demo derby cars. Then they went onto a 383 that went through 2 more demo derbies and then the 383 went right from the derby car into a 67 Coronet Station. That Station Wagon went to Mopars At The Strip in 2005. There at MATS we put the Coronet Wagon on the chassis dyno where it made 300 HP and 330 TQ. I'm pretty sure that 383 had an old hydraulic flat tappet Crane cam of about 300 degrees advertised duration and we were using solid lifters on it. The rocker arms we used were a strange looking affair. They looked just like stock factory 383/440 stamped rockers, but they have adjusting screws in them so you have to use ball and cup pushrods. Still have those suckers in a box up in storage.

Those heads are flowing:

Lift.............INT/EXH

.100............86/60
.200..........154/117
.300..........204/156
.400..........234/186
.500..........253/205
.600..........257/220
.700..........262/228

Should be a good test to see what kind of power a 440 will make at about .450-500" lift.

 

[tallhair]

516 heads are the old closed chamber design with a flat "old style" intake port. Valves are 2.08" / 1.60"

915 heads have the same chamber as the 516 but a much improved intake port. Valves are 2.08" / 1.60" and 2.08" / 1.74" for HP. As far as I understand it, the 915 head port design was changed based on recommendations of Harry Weslake (as in Gurney/Weslake fame).

906 heads have an open chamber just like you see on all the 70's vintage heads but the same intake port as the 915. Valves are all 2.08" / 1.74".

For some reason, and I have to believe it's emissions related somehow, the 346 and 452 went back to the flat intake port floor just like the 516's. On a dry flow bench these heads may all flow equally, but under actual conditions (wet flow) the 915 and 906 might have an advantage over all the other iron heads.

Which do you think is better between the 915 and 906 stock unported heads with flat top pistons Meep .. with the 1.74 valves of course? Also which one reacts best to the bump up in valve size?

Or are we gonna find that out on this test IQ52?

 

[themechanic]

I don't want to sound like a dumbass, but I'll ask anyway. What is the difference between the heads 906 516 916 etc? I'm a MOPAR virgin.

You're not alone, Bro. I did not have a clue, either until I read this exhaustive comparison.

Link: http://www.moparmusclemagazine.com/techarticles/5115_cylinder_heads/

 

[Meep-Meep]

Which do you think is better between the 915 and 906 stock unported heads with flat top pistons Meep .. with the 1.74 valves of course? Also which one reacts best to the bump up in valve size?

Or are we gonna find that out on this test IQ52?

The intake port configuration is the same on the 915 and 906 so neither would benefit greatly from a valve size increase unless some serious port work was done. However, the compression bump from the 915 might provide some help for a low compression engine with a bit of cam. The tighter quench distance from the closed chamber may also help, but unless your piston is at zero deck you may not notice any benefit from the tighter quench. Plus how would you measure the results? I like the 915's because they have the best port of the OEM heads and the closed chamber helps get decent compression with a flat top piston.

 

[Gpuller]

Well, we found the 516 heads we had used a long time ago. They first went on a 413 with 11:1 Max Wedge pistons. That engine went into 2 demo derby cars. Then they went onto a 383 that went through 2 more demo derbies and then the 383 went right from the derby car into a 67 Coronet Station. That Station Wagon went to Mopars At The Strip in 2005. There at MATS we put the Coronet Wagon on the chassis dyno where it made 300 HP and 330 TQ. I'm pretty sure that 383 had an old hydraulic flat tappet Crane cam of about 300 degrees advertised duration and we were using solid lifters on it. The rocker arms we used were a strange looking affair. They looked just like stock factory 383/440 stamped rockers, but they have adjusting screws in them so you have to use ball and cup pushrods. Still have those suckers in a box up in storage.

Those heads are flowing:

Lift.............INT/EXH

.100............86/60
.200..........154/117
.300..........204/156
.400..........234/186
.500..........253/205
.600..........257/220
.700..........262/228

Should be a good test to see what kind of power a 440 will make at about .450-500" lift.

That many derby's and the heads aren't cracked? Amazing.
Are those 516's stock valves w/o porting?

Thanks!