Crossflow Epiphany!


After two years of tinkering with the Crossflow heads, trying to get one to fit a US 200, we had nearly given up. We had sawed, welded, machined, and wrecked many 200 blocks in an effort to duplicate the geometry of the Crossflow deck. :unsure:

Today, I stopped by to pick up a head and we were looking again at some of the carnage when suddenly it hit us! :idea: We had been approaching this thing incorrectly the whole time! :duh: Our ideas had revolved around cutting and welding sections to the block to make the deck face end up looking like the Aussie block. It takes a lot of heat and a lot of (expensive) 99% nickel rod to make that work. We had actually roasted our last block in a charcoal fire to preheat it! Almost 7 hours of welding and machining ensued.

But then it occurs to us, why bother? :unsure: Let's just add enough to provide pushrod clearance and head gasket support. There's no pressurized oil or water in that area, so no need for any great integrity. An hour later, viola, we have a prototype system!

Here's the kicker.....NO WELDING! If this thing works the way we expect it to, it's a bolt on. You'll need a drill, a grinder, some common hardware, a little steel, and some patience. A few holes need to be tapped and filled, some need to be drilled open. But this is a mod anyone should be able to do in the garage with handtools. there are a couple of head mosd to do as well, but again, no welding.

More this weekend as I take pics and put up a page on this. I think this will work! 200/250 cid US Crossflow conversions may be a reality! :D
I guess it goes to show the KISS principle really works!

I, among others, eagerly await the lowdown!

Awesome news! I was looking at a buddies x-flow 250 here in town last week and was thinking that there had to be a way around welding up a new sealing surface.

So, who wants to mail me an AL x-flow head :unsure::
Thinking about it, if the oil/rod gallery isnt exposed, then it should be fine.. All of the head bolts clamp the head down around the cylinders, and the water passages are on the other side of the head..

Pick me John!! :LOL:
There is a downside. While this technique requires no machining, it is not a true bolt on like the 2V head.

This cannot be done in the car. You must pull the engine to clean out the metal chips that you will produce from the drilling. But, you wouldn't want to put the head on a worn out engine anyway. :)

For this conversion you'll need a crossflow head w/rockers, intake manifold, exhaust manifold or headers, valve cover and an Aussie gasket head set.

Since the port spacing and rocker oiling is now different, you'll also need a Crossflow cam, small block Ford lifters, and some custom oil-thru type pushrods. The DII distributor will NOT fit due to height, so a pertronix or some other solution is required.

But the airflow of this head, while considered good for a 250, is OUTSTANDING on a 200. The ports are smooth and straight, the valves are large, and you don't need a lot of cam to make power. EA 3.0 says 178hp @ 4400 with the stock Crossflow carbie cam and my dual Strombergs CD 175's. Reality is probably going to be closer to 165hp, but in a 1300lb car, that should be enough!

The head choices are getting to be too much!

I hope this works out because I'm beginning to get a little tired of folks bagging the little 200 (no one here, just some V8 folks I know).

So now there's modified stock, Argentina SP, Argentina ME, Australian 250 2V, and possibly the X-flow.

Can hardly wait to hear more!

Dean T
BKNLINE":2unqf0wd said:
So now there's modified stock, Argentina SP, Argentina ME, Australian 250 2V, and possibly the X-flow.
Add the factory config, and that makes six.

Waiting for the first "sampler" head with one chamber of each. :LOL:
At last, an American with his head screwed on right!

I checked a lo-deck US spec 200 in an XR1967 Falcon a while back, and remembered the old Aussie guys who used to template the block and drill and spacer plate all manner of adaptors for there stroked Holden Grey engines. Started off at 130 cubs or so, ended up with twin cams alloy heads and half inch taller blocks for long stroke cranks. Try 180 cubic inches! Anyway, the cross flow on US 200 lookes like a match made in heaven!

Jack, guys who used to put big valve heads on little British Minis used to get plumbers gromets and tighten them up in the block to stop swarf getting through. A little vaseline and out with the grinder to sink some relief cuts for the huge valves. On the lifter gallery, there isn't a regular shape, and the swarf gets all over the place :cry:

And addo

If this is XECUTE's system, I'll back his lawyers.

The real lawyer would be Merv Waggots, the Grey engine Holden modifier of the 1950's. I think the statute of limitations ran out about 20 years ago....and besides, I'm not American, I don't need Juge Wopner, and People Court. (He's busy judgeing dog cases now)

And Jacks new mission is a gun-runner for Aussie Alloy Heads. Knock 'em dead, Jackie!!!!
" Forest , what forest, I don't see no stinking forest, the ^%#@* trees are in the way."

Have you ever heard of "target fixation". After pulling all your hair out, destroying tools and parts, spending/ wasting large sums of money, developing a vocabulary the wife does not like, up walks the idiot kid from next door asking a silly question and the answer show you the easy way to do it. ;)
so when are you opening the "inline 6 shop"? I will drive up from Miami to have this done....

take LOTS of pictures!

MustangSix":dnbxq1dz said:
Reality is probably going to be closer to 165hp, but in a 1300lb car, that should be enough!
So the 200/250 cid US Crossflow conversion prototype is going in the Locust! Wow that's awesome.
Are you going to post a step-by-step instruction with a materials list?
Maybe if the prototype works you can create a kit and bring over a couple dozen Crossflow heads. This is the carberated Crossflow, would this work with the injected version as well?
Based on availability aren't the Crossflow heads about 1/4 to 1/3 the cost of the 250-2V heads?
I already have a couple 250-2V heads but this is great news for those looking for high performance low cost options.
That is great Jack. Maybe you could work a deal out with AZCoupe to market a kit. It seems that he already has all of the import issues worked out. You deserve to make a little money on all of the work you have done. Of course, you know that many of us envy you. You have all of the time, money, connections and most of all the smarts to do some really neat stuff. Will you post a sticky or tech page with all of the details?
If you nose around the classifieds, a head will be about AUD$50 with no manifolds.

The EFI manifolds can run to $150-180 more, the EFI gasket set is $50, aftermarket carbed manifolds are $200-up new, and $70-up used.

Remember the exhaust manifold is different and non-interchangeable with the earlier motors.

The ignition is a sore point. I would urge people to bush down for the Oz unit.

Oddly enough, it's only a hop, skip and jump to OHC swaps if this project works out. At least, I think so... :roll:

Cheers, Adam.
The OHC is so diferent that there is no way that you could do a conversion. That would have to be a complete engine swap.

Time, money, connections, smarts? Most days I can't muster 1 out of those 4! :roll:
Hey Jack,

What were the head specifications that you plugged into the EA3.0 program? :unsure::

Good Luck