W5 heads should I?

[12swinger]

I have a dart that I put a 340 in for some summer cruising, and it needs to go to the body shop for some paint work.
I currently have w2 heads on the 340, have very little experience with w anything, as I ran ported j heads last time car ran.
The question is I also have some w5 heads that are nearly ready, I did some port work, not much, mainly bowl work, removal of casting flash, maybe a little more here and there. The w2 heads have a little bowl work, chamber work, there done.
Are the w5 a significant power increase over the w2?
I actually had intended to put the w5 heads on a little bigger engine I have, close to done, 360 .070 over rare 70 date code block, perfect casting, BRC pistons, eagle rods, etc.
I should probably be patient and just run the w2 heads, and see how it runs.
But I do enjoy beating it at the drag strip, and have been wanting to get this car in the 10s on the motor.
First post, I stumbled on your forum checking out oiling improvements to the bottom end to make it survive at 7,000+ rpm.

 

[70aarcuda]

unless you flow bench the heads ....you wont know which head is better.

 

[12swinger]

unless you flow bench the heads ....you wont know which head is better.

I used to have access to a flow bench, not anymore. I moved 600 hundred miles from it. I'm not sure of anyone in my area with a bench.
The w2 is impressive looking, no radical work on enlarging the port, but beautiful work in bowl, and chamber. I bought them on eBay this way.
The w5 was a mopar nats new purchase, that I picked up the templates for, and tried to not go crazy, boy that aluminum cuts easy though.
Is it a good idea to run some more compression with aluminum heads?

 

[rumblefish360]

Tony is dead nutz on be ause the real differance is in the head flow. The W5 can be ported out a little better than a W2 head, BUT, if you do not use the potential then there was a waste of time money & effort.

You can run approx. 1pt. more in compression.

 

[12swinger]

Ok you guys are making more sense. I just remember some years ago I flowed some w2 heads that were similar to mine, and they flowed a few cfm more then my ported j heads. Not a significant gain.
Unfortunately the old j heads turned into water sprinklers, and there retired.
I didn't really want to purchase another cast iron head, but I sold some TA heads and ended up with one of the best deals on some w2 heads with intake, I just installed new exhaust valves, and a valve job, and there ready. Plus I had enough cash left over to purchase the w5 heads. 2 for 1

 

[tubtar]

You WILL have a pretty good chunk of weight taken off the nose with W-5's.
You will also probably want to have them pressure tested to ensure the integrity of the castings. There were some porosity issues with the earlier castings as I understand it.
Some of the best info on MoPar heads for free is right here........
http://shadydellspeedshop.com/moparheads.htm

Lots of tips on what to expect and what to watch out for.