74roadrunner440
Well-Known Member
any one ever use the 440 source heads that are closed chambered and better than factory heads?
Yeah, IQ probably has more experience with them than anyone. From what I have followed they work well. For a while it was reported that they had crappy retainers and keepers but changing those out with quality pieces was the fix. As with any new head you really need to examine the spring set up, valve job and guide clearance, etc.. and make adjustments accordingly. However........ This leads me to another conclusion. If most of the source heads need to be touched up to make right (and that work isn't free) then you will be into them for over $1000.00? If you just want a good driver you can have a set of factory iron heads done right the first time by a good shop and have possibly under $1000.00 in those. Sure you will sacrifice some flow potential but will it really matter if you just want to have a hot street car? A cam can work around the flow issue to a point but you must choose wisely. I'm doing well with all factory parts.
My thinking is this - if you spend the $655 as IQ mentions (bringing the total to $1655 for the 440 source heads), why not spend the extra $345 and get them CNC ported and completely gone through by Modern Cylinder Head for total out of pocket of $2000.
But then you get into a case of the 'might as wells' and there is no end lol.
Personally I think you can't beat new technology. Even if you have to prep the stealth heads I think your still miles in front of the old cast iron tech. It was good back in the day, and that raised the bar for all. Alloy heads save weight and keep cooler as alloy dissipates heat better so your better off even without better flowing ports. Look at the CFM stats with the Stealth heads or even Edelbrock Performer RPMs, don't forget the valve lift potential too. Either head on a 440 with 30' over bore (which most of us build these days, equates to 446 cubes), rev it to 6500RPM which is the max RPM power potential for the Eddy heads at least, with a M1 intake, (these are hugely underrated), and 950CFM carb and you make 500-550HP all day long. Can you say street Hemi HP?
A stock 440 bottom end will handle the RPM, even the Edelbrock supplied steel rockers and springs will take it too. Check with 440Source I'm sure this wouldn't be too much to expect as well. The real secret is air flow and mild RPM, we all know what happens when you put a 650 carb and 4BBL manifold on a stock 2BBl 318.
I've heard/read, that with a forged bottom end and stock 440 cube configuration, with good valve train setup and ported 906 heads, together with matched intake and at least 1000CFM carb, revved to 8500RPM can make 750HP. Imagine what you'd make with the alloy heads at this engine speed. Even at 6000RPM and a good size carb and single plane manifold I think you'd be surprised at what you can achieve. The 509 Lunati cam seems to be a popular combo with the Eddy heads and if your going with either those or the Source heads I'd at least get in touch with comp cams for your particular needs.
There's no replacement for displacement, the secret lies in utilizing the cubes you have correctly I believe.
Good advice Budnicks
Still waiting for some more reports about the 75cc E Streets. I'd be interested to know things like flow rates for them against Stealths and RPMs if anyone knows of any links to such info.
The only thing I don't like about any of the Edelbrocks are the angled plugs and possible fitment issues with my Hooker headers. I've been told they can be made to work with some dinging here and there but it seems like a big chance to take.
The Mopar Performance version of the RPMs have straight plugs but they cost even more than the RPMs. I think the least I've seen them go for is $1800 from an Ebay retailer.
I talked to Ed Viceroy (Junkyard Ed) a well-respected SoCal BB Mopar head porter and he said he could do me a set of 906s, CC'd to 86cc that would outflow the Stealths for $900 out the door. I mentioned my 452s and he said he wouldn't port them for me, called them "truck heads".