W2's vs. Edelbrock RPM

[cudadave72]

Since I bought my car with the engine already together all I can tell you is that the heads are fully ported. I can also tell you that the car pulls hard as a train till I pull gears at around 6200 RPM. It is a 416cu in engine. The car also has around 12000 hard miles on this engine. The last time I had it dyno'd it was way out of whack and still managed 400 to the ground (about 500 flywheel) with a very streetable cam. There is at least 30 to 40 left in it for sure! As many on here know I drive this car any and everywhere! I dont mean to cross anyone here but I think its hard to argue that there is potential in the Eddy heads when a full weight 3600lbs small block can pull low 7s in the eight mile hauling a 250lbs driver on drag radials!! Could be faster with different heads but I am still pleased.

[71chally416]

The operative word there is "Fully ported".

[moper]

IN terms of usefull airflow, the intake valve can be not larger than 51% if the bore its feeding, before shrouding becomes such an issue that the flow will simply not improve. Especially with a higher lift cam. Most shops test with a 4.25 bore fixture, and the really skews the info. (it's easy to make a flowbench read anything you want) So, on a typical 408 with a 4.03 bore, the 2.02 valve is as big as you want to get. Plus, the volume of the port vs tha curtain area has to be kept ina  decent relationship. A larger (say 2.05) intake valve has a larger curtain area, and you can make the bowls larger, and then go way turbulent thru the pinch. The best ports flow fast and smooth and they don't generally have larger valves. A 416 (4.07 bore) is fine with bigger. I have run larger intakes (2.05) on 4.07 and 4.10 bores with no appreciable loss in torque noticed. The RPMs flow what a well ported J head does, only they do it with a relatively small volume port. Still not "302" small, but fairly small. RPMs in fully ported form will feed very close to 600hp at 6500rpm. Over that, they will stall. Totally box stock versions will move enough air with the proper cam to make 500hp at 6000. But beyond that i terms of power or rpm, they will need help. Shady Dell Speed Shop has some killer programs for them. I would consider the W2s to be "the next step". RPMs will more than cover most builds. 

[71chally416]

You can modify cylinder heads for no apparent flow gain on the flow bench and they will still rock your HP/TQ numbers on the engine dyno.
Not many people will be able to discern if a motor is starting to lose HP over 5,500 rpm. It will still feel strong over 6,000 when the ideal shift point might be 5,700. That's where an engine dyno trumps a flow bench every time. It defines your ideal shift point for you and tells you how well your heads are working while the motor is running. The BSFC figure is what I look at.

[moper]

Anyone can modify and get no apparent gain...lol. The trick is to do it AND find a gain. You dont see it peak flow. You see it at low and mid lifts and mach number, and you'll see it in the BSFCs when it's actually run when the wet flow is correct.. But you will always see something if it's done right. I agree, it isnt about just cfm numbers. But that comment enables a whole bunch of peolpe to hog like heck and say it helped...lol. In  terms of a dyno, the engine dyno is only a tool. The real deal is in the car, when there is shift recovery, air flow from under hood, temperature extremes, and inertia in regard to fuel mixtures, no mathematic conversions for baros or temps. You can race dynos all day... read Enginemasters and you see that. Anyone can make a bench, or a dyno, say whatever they want. It's no more than a tool to note trends.

[71chally416]

The old engineering saying is "Garbage in, garbage out". A dyno is only as good as it's operator. The MPH and car weight w/driver is always the flow bench and dyno fact checker. We've all seen the 2,600lb Vega with 600 HP that does 11.90. 

[Rob C]

I do alot of reading here, mostly in resto. After reading this, I have one thing to say, Good work and write up Moper, tell'em how it's done.

OH, also, the 302's are NOT what you want on a 340 or larger engine for any reason, shape or form, PERIOD! The volume and port shape need to be matched up with the engine specs and intended useage. The valve size is important. 2.02's are not needed in many cases and is often overkill in milder builds.

[71chally416]

OH, also, the 302's are NOT what you want on a 340 or larger engine for any reason, shape or form, PERIOD! The volume and port shape need to be matched up with the engine specs and intended useage. The valve size is important. 2.02's are not needed in many cases and is often overkill in milder builds.

I guess then I blew it using big 2.02" valves with my 12 second 109+mph 7.9 to 1 compression 318 that had a .470" lift cam and a stock convertor. I should have used smaller Intake valves. Oh, that's right, I had the stock 1.88 valves in the smogger 340 heads I had on it when it was doing 13.50's with everything else the same...   

[Chryco Psycho]

obviously yours is not a milder build
 matching all the components to work together is the real key

[71chally416]

obviously yours is not a milder build
 matching all the components to work together is the real key

It's outlined in the proven combo section here>
http://www.cuda-challenger.com/cc/index.php?topic=46967.0

Don't know how it could be much milder than that. The pistons were .080" down in the bores and it had '70 340 heads with the open chambers. I used the cheapest regular gas I could find. I think the 340's and 360's are seriously under-headed, just like the 440's. You can't make the stock ports "Too big".   

[Chryco Psycho]

there is a balance between size & velocity but generally production heads are under sized & under valved for max performance but they make one head work for all applications from trucks to performance so compromises are made , cost has to one of the biggest factors

[VitC_AARcuda]

 Basically the last head I would look at is the eddys , the set I looked at had horrible core shift , I am done with their half assed engineering & terrible QC
W  anything will outperform the eddy , poersonally I have had great results using the 308 casting which still used rocker shafts instead of GM ball stud rockers
 Be warned W2 are expensive to set up by the time you buy rockers puishrods inatke & exhaust & yes the W2 uses a different valve cover too But do not buy the Mopar one it doesn`t fit the W2 head , for some reason mopar cannot make a cover fdor their own heads  , $450  mistake to find out

i have raced small blocks with W2 heads for 10 years,,,,originally used moroso chrome steel valve covers and now been using Mopar Cast Aluminum valve covers...the same ones that fit the normal J or X heads....Dont know where you are getting your info from...

and these valve covers also fit the W5 head too.....

[71chally416]

They fit right on the ones I had as well 

[Chryco Psycho]

the W2 Valve cover sold by Mopar don`t even clear the rockers on the new heads , we ended up using the normal cast covers but had to notch the covers for clearance where the pushrods hit them ,, we used the latest casting maybe things are positioned differently with them 
 The Info I have is actual experience on the engine we built last summer

[71chally416]

That's odd. And these B-1 big block rockers actually clear the Moroso covers on my Commandos