Evolution of Big Block Chrysler Cylinder Heads: From Factory Iron to Aftermarket Aluminum

Mopar Connection's Kevin Shaw and Jim Hannan go over a quick overview of the evolution of the Chrysler B and RB cylinder heads, and how the aftermarket both resolved lingering issues with these and improved upon their designs. It's certainly NOT a comprehensive review of all factory iterations nor the entirety of the aftermarket offerings, but a beginner's guide to what to consider before building your big block.

This episode is presented by Callies Performance

Find most everything shown here at Summit Racing:

Edelbrock E-Street 75cc RB440 heads

Proform Aluminum Roller Rockers 1.5:1

Trick Flow Power Port 270cc heads

Indy Cylinder Heads

440Source Stealth Heads

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#moparconnection #summitracing #edelbrock

[thomasward]

I've had pretty good luck with Edelbrock cylinder heads, unshrouded the valves and did a good valve job on them and they flowed more than any stealth head. Plus I hit them with 250 shot of nitrous for many years and no problems

[codyhollinger]

Last year my mild port 906 cracked. Looking at the cost to work up another iron set I chose Stealth heads. They were the best choice for mild build. So far I am very happy with them.

[jarmominkkinen]

I have Nice MP 425 Aluminium heads. FLow Nr 310cfm (0.585 Lift)..Good Hp 640Hp..In May Challenger 70SE sixpack 440cui!!!

[tazman]

Those heat riser holes worked for a while till carbon would seal the holes shut I had a 318 that I tore down to re seal the engine and I had to chip away the carbon that was packed in them heat riser ports and I tore the same engine down about 4 years later to rebuild it and the ports were damn near blocked off with carbon again so they don't last long before they become blocked.

[stephenwest]

Not to make anyone cry, but in 1964 they would have gas wars between the local stations, 5 gallons for a dollar, normally .23 cent a gallon.

[robertmcelroy]

where can i get that intake manifold gasket

[craigcontofalsky]

How about the 426 Stage lll heads? Larger ports and bigger valves. 1.88" exhaust if I remember correctly? I raced Mopars in the 70s and the Stage cars 62-64 were fast cars in Super Stock classes.

[mikebartley]

Rumor was the Heat risers were installed to keep the motors Cubic inches from shrinkage in the cold winter days before you took it out on a cruise...

[smilsmff]

In 1980s they raced for 20 dollars on the streets. on back roads or a tank of gas

[tazman]

Firing order the same as a SBC only the other way rotation makes it real easy if your a Chevy guy and the 1-8 cylinder numbers are the same too not like Ford being all different in firing order and cylinder #

[robertwetherington]

They need to evolve more . Even the trick flow 270 aren't that impressive. Chevy BB heads the small ones are 270, big ones are 365 and we won't even talk about symmetrical designs.

[davidjenson]

Prove with dyno tests edelbrpcks are superior tp 906 heads

[ThePaulv]

Factory heads are alright with a lot of work.
Believe it or not the smog heads flow about the same as the 915/906 but with less porting.
Check out a 4 part article called Cylinder Heads part I, II, III and IV by Steve Dulcich.

He really gets into it in the articles. 280 and 220 CFM at reasonable not stupid valve lift. Valve size is interesting. The exhausts prefer a smaller valve than the 1.81s that were in fashion 25 years ago (with some caveats).

Of course no one would bother these days with cheap light heads costing half the labor of porting factory iron heads. Even crappy aluminum heads flow out of the box 280 and 220CFM but OEM iron heads can be made to flow reasonably.

The articles are still on the internet. A great read but long. If you have a short attention span you mightn't like them.

[jimkillen]

When i was in my early 20s..i has a couple of mopar ..A 68 charger that put a 426 wedge out of a marine application. A 66 Belvedere with a 440, a 4 speed, 9 inch dana . . I perfer a engine that can makes hp past 5500 or 6000 . I just thought that right or wrong the mopar wedge did not have enough cylinder head flow to make the power i wanted . At least the heads i had seen . So i moved on .. Be interesting to see what was or is available in cylinders heads . . I just thought that the hemi was the what mopar used to make the power i liked

[tazman]

Mopar need more performance heads there is not much to choose from if it's a LA/Magnum you got Edelbrock and Trick Flow and a few other of the same combo and we still playing with blocks that were made in the late 50's early 60's technology even Magnum engines you think they would of used it to design a better block but all the did was change how the valve train was oiled something Mopar never had a issue with and that was it. Now the whole V8 engine thing for Mopar is now gone thanks to a European company taking it over and going to destroy any part of Chrysler that there is left.

[markholroyde]

I was the first person ever to buy a 440-1 kit from INDY Cyl head outside of the states. It was in 1990, I flew to Orlando from the UK and drove to ICH through the night to pick it all up, I had a guided tour of the place by one of the Bros...then drove back and flew home with the full kit carried on as hand luggage. they went on a '64 Signet I built with a 440 under them, went 10.15 off the trailer and took Europe by storm. I have a '68 Roadrunner ive owned 41 years now, stock 383 I gut it to 12.59 best in 1989. I have just put some Edelbrock heads on it and 2 of the valves are 15thou lower than the others...progress eh LOL

[vipottaja]

The factory BB heads are awful. They are not like chevy SB heads at all, they do not have a short side in the ports, and the valves are about the shortest in the industry.

Being that awful, they actually work pretty decently slightly ported. Maybe thanks for the effort that Direct connection put in them.

The 906's are NOT the same as the later heads. The difference is in the intake port, 906's actually had some short side and shares the port design with 915 closed chamber heads.

The exhaust ports in 915 & up are practically the same, as are the intake ports in the post 906 heads. The 452 heads didn't have hardened seats put in, the seats were flame hardened, gone after first valve grind.

[M-codebird]

My view is what are you going to be doing with the engine . Every head has a benefit. But it comes down to money and common sense. You’re not going to port 906s and spend 2k doing that inless your racing in a F.A.S.T class . I do prefer Trickflow stuff for a pocket friendly parts and like how they try to make it factory style bolt on

[marktrevisan]

Edlebrock crap, 440 source decent stock replacement plus a little, AFR decent, Indy decent.