Hemi heads capable of 600HP!!!!

[vvv90]

Says Fastman.

Interesting.

http://www.dodgetalk.com/forums/showthread.php?t=5184

[Redman]

Go down to your local Dodge dealer and try driving the SRT-10 Dodge Ram: (http://www.allpar.com/model/ram/ram-srt-10.html).
What a beast, and that was only 500 bhp (372 kW) @ 5,600 rpm
Torque: 525 lb.-ft. (678 Nom)@ 4,200 rpm.
How does one "civilize" so many horses?

[II kings 9:20]

How soon does the tranny blow with all that HP

[goddardzilla]

Originally Posted by vvv90

Says Fastman.

Interesting.

http://www.dodgetalk.com/forums/showthread.php?t=5184

vvv90
Thanks for bringing this to our attention - I know you are not responsible for what this guy wrote.

David Vizard was way, way ahead of this guy in analyzing how well the stock hemi head flows and how it can easily be improved

Nice pictures, tho no proof, in his post of his 600hp claim - just speculation. He's using this post to promote his business.

BTW: Those look very much like anti-reversion valves that Chrysler has used

Interesting.

Zilla

[vvv90]

Originally Posted by goddardzilla

vvv90
David Vizard was way, way ahead of this guy in analyzing how well the stock hemi head flows and how it can easily be improved

Then please post. I'm sure we're all familiar with his "Hello Hemi" Popular Hot Rodding article. He's one of the world's most renowned flow researcher but I've yet to see his opinion on this heads and flow capabilities and I would like to.

Nice pictures, tho no proof, in his post of his 600hp claim - just speculation. He's using this post to promote his business.

I think you're taking this a little too far. He only posted flow numbers which I personally can see supporting (maybe with even more port work) and boring and stroking these heads supporting 600HP. That was the point of my post. Nothing more.

BTW: Those look very much like anti-reversion valves that Chrysler has used

Interesting.

Zilla

I don't know how you can tell, from what I know the anti-reversion lip is on the top of the valve. But I'm sure it would be necessary if running big headers and an extreme cam to maintain low end torque, however it would sacrifice the flow if you're shooting for high end "brag-able" HP like Fastman is...Anyway, off topic. It seems like Fastman is definitely serious. Don't get me wrong, 600HP on a small block is ridiculous for a daily driver.

To answer another poster, yes the tranny would blow easily, but that wasn't the point of my post.

[goddardzilla]

Originally Posted by vvv90

Then please post. I'm sure we're all familiar with his "Hello Hemi" Popular Hot Rodding article. He's one of the world's most renowned flow researcher but I've yet to see his opinion on this heads and flow capabilities and I would like to.

Sure: directly from his article, Vizard's opinion on the flow capabilities

Flow Capability
We can see that Chrysler's engineers were targeting the best two-valve head possible. There are two important questions that need to be asked here: How well did they succeed for the head in stock form and, since no aftermarket heads are available, what is its porting potential? The graph, Fig 3, gives the answers here and you are going to like them. First, the intake port. The stock port with its 2-inch valve flowed a whopping 270 cfm at only .600-inch lift. It hit the peak flow figures, which are produced at .700-inch lift on a stock LS6, at only about 375 thousandths lift. This is good news but there is a lot more. Peak figures are not the whole story. Good mid-range figures are also important. The new Hemi did extremely well here. At 250 thousandths lift, the stock head was nearer a $10,000 Winston (Nextel) Cup head than it was to even a good modified parallel-valve head.

A check on the intake port velocity (Fig 4) showed the intake to be a super high-speed port with valve-to-port areas very similar to what is seen in Formula One. Velocity probing showed 90 percent of the port flows at a velocity greater than 90 percent of maximum. This is far better than a typical 23-degree performance head for a small-block Chevy or, for that matter, the LS6.

The exhaust port showed the same high-function trend by hitting 161 cfm at 600 thousandths lift through its 1.55-inch valve. It also had a far better than average port velocity and velocity distribution (Fig 5).

We spent a day and a half on the flow bench in an effort to find out what this head does or does not like in the way of port mods. We are sure there is much still to come, especially with some bigger valves, but we did find what it took to produce, at 600 thousandths lift, some 302 cfm on the intake and 195 cfm on the exhaust. As the nearby photos show the work to achieve this proved simple. In essence, the porting involves little more than just tidying up what Chrysler's engineers provided in the first place (great job guys).

I think you're taking this a little too far. He only posted flow numbers which I personally can see supporting (maybe with even more port work) and boring and stroking these heads supporting 600HP. That was the point of my post. Nothing more.

Maybe, I used to own a high performance shop, and this caused me to analyse all claims with a critical frame of mind - maybe your right; I guess I am just a bit jaded. I'm sure many other's like me came to conclusion's about the Hemi heads supporting high HP, based on Vizard's published work way, way before Fastman's "you heard it here first" headline

I don't know how you can tell, from what I know the anti-reversion lip is on the top of the valve. But I'm sure it would be necessary if running big headers and an extreme cam to maintain low end torque, however it would sacrifice the flow if you're shooting for high end "brag-able" HP like Fastman is...Anyway, off topic. It seems like Fastman is definitely serious. Don't get me wrong, 600HP on a small block is ridiculous for a daily driver.

Several types of anti-reversion valve are available. Here is more information on the type with a visible Anti reversion lip on the combustion chamber side, in the Fastman's picture.

See this link: scroll down to page 12 and see the sidebar “rimflow valves”

http://www.aptfast.com/Pdf/CatAPT2002all.pdf

I used them in one of my own engines.

vvv90 it was Fastman's bragging that caused me to react, I am not getting at you - I generally like your informative posts and comment.

Zilla

[vvv90]

Originally Posted by goddardzilla

Sure: directly from his article, Vizard's opinion on the flow capabilities

Yeah I remember reading that, but I'd like to see him modify some heads and actually see what the flow numbers are. I'm still blown away by the mere flow in stock form over the LS heads. Simply amazing.

Maybe, I used to own a high performance shop, and this caused me to analyse all claims with a critical frame of mind - maybe your right; I guess I am just a bit jaded. I'm sure many other's like me came to conclusion's about the Hemi heads supporting high HP, based on Vizard's published work way, way before Fastman's "you heard it here first" headline

Yeah, I will look forward to hearing more from him, but there will be a lot of aftermarket engineers dedicating their work to making these heads perform so I'd still like to hear more from Fastman since there's not many people doing any work....Here's a site that actually offers worked hemi heads. It looks like the flow numbers Vizard claims can be bought right now. They didn't even up the valve sizes and look at the .600 lift flow numbers!

http://www.lmperformance.com/5354/75.html

Several types of anti-reversion valve are available. Here is more information on the type with a visible Anti reversion lip on the combustion chamber side, in the Fastman's picture.

Ok, I wasn't sure if the dome, or cupping of the underside of the valve was directly related to them being anti-reversion valves or not. I wonder how they will affect the top end. Like I said before, I've heard it's a trade off. If you're running such a radical overlap cam (No low end backpressure) the anti-reversion might hurt the 5000-7000RPM power output.

vvv90 it was Fastman's bragging that caused me to react, I am not getting at you - I generally like your informative posts and comment.

Zilla[/quote]

As I do yours. Thanks for the info Zilla!

-Matt