Crossflow/US200 pipe dreams (again)

OK, here I go again. I'm still a little ways off from having the machine work done (the Falcon floors need replaced, all my $$$ is being diverted into the new house like you wouldn't believe!) but at least I have a decent garage now.

Things I have figured out:
My alloy crossflow head is one of the mid-80s, EFI-equipped, high-swirl designs with fairly small CCs. After milling and having the valve-work done, I'm probably looking at 48-50cc chambers.

The valves will be 2V 351C valves @ 1.656" exhaust and 2.045" intake. The rockers will be 1.72:1 Cleveland roller-tip rockers.

The cam will be a mild one, since the displacement is only going to be ~200 CI. I'm thinking about the Crow #14678 or #14613.

Things I need to figure out:
Dizzy... this is going to be a little bit of a headache. It looks like my '72 dizzy with Pertronix is going to be a little too close for comfort with the intake crammed right on top. I'm looking toward the crab-cap from a later Mopar V6 (Sebring/Cirrus, etc.) to see if that will help clearance and also be adaptable to my dizzy. They are pricey from the parts store, so I'm still waiting to stumble across one in the boneyard so I can do a mock-up and see what is necessary to make it fit.

Target CR. I'm thinking that 10-10.5 is doable with the alloy head if I'm careful about the combustion chambers. Am I way off? With the high-swirl head design, would I want dished pistons, or flat-tops? I have to admit, I'm quite in the dark on this one. This car is by no means going to be a daily-driver, so fuel cost is of little concern. The thing is, the CR needs to be a consideration from day 1 of the buildup. It will help me determine how much overbore I want (I prefer to keep it under .040 for the sake of retaining cylinder wall strength/stiffness), how much decking I want, and whether I just want to skim the head or mill it more deeply. Looking at the CCs, I probably don't want to shave too much off the head because they are pretty shallow as it is.



Thoughts?

hey
if you ahve the money the best setup to make a complete copy of the combustion chamber in the piston like 5cc this will help with the swirl effect.
otherwise flat tops dished depends on what you wanna do with your head to releave it etc.
the head you have is a pretty good one and dont detonate like the closed chamber ones.
drift

How about these ones which are intended for the 2.3 HSC 4-cyl? http://www.kb-silvolite.com/spistons.php?action=details&S_id=539 Seems like Ford's "high swirl combustion" designs would share something in common, so maybe flat-top is the way to go?

Firstly you wont get those valves in the head, and they are quite OTT on 3.3 litres, the aussie 200 sixes rev up plenty eeven with a puny carb and manifold, keep in perspective what your doing.
My advice would be to run whatever pistons you can get with flat tops to get your CR to around 9.5. Bare in mind that high CRs were with sngines that had poor volumetric efficiency (cylinders never filled) Keep to a smallish cam but dont skimp on valve train parts even to the expence of running solid lifters etc etc.
A smallish carb , say a 350 holley will still give good results.
is this auto or manual?
A7M

The valves in the head are right around 1.5" exhaust and 1.75" intake (haven't pulled them so that could be off by a 1/16" or so.) I'm still trying to find a US source for valves this size. Most of the "finished" valves in those diameters are coming up a bit too short so I may need to have a set custom-fabbed.

Looks like the carb will be a 4bbl Holley. I have one that I believe is rated at 390cfm.

As of this moment, I'm looking at a C4 auto with a high-stall converter. Things may change between now and then and I might end up with a T-5 in there by the time everything starts to come together, but that would cut considerably into the engine and body budgets...

I'll shoot for 9.5ish compression with an advertised "low-to-midrange" cam to keep things reasonable. Even a stock EFI cam should breathe plenty at the high rpms since it would be spec'ed for 25% more cubes than what I've got with the 200.

if the phots are of your head then its an earlier non swirl head with 1.75 valves, the later heads had 1.84 1.55 valves, but for your use I still advise sticking to the stockers, they will be quite sufficient for 200ci.
A four barrel is overkill even a 390, and the manifold for a four barrel isnt too hot. Do you have any intake manifold at all? if youve a got a stocker then you might be best to work with that. the stock weber two barrel intake is an intelegent design but too small for 250ci, however a better thing for 200ci. Ive driven brand new 200 crossflows that would rev out to 6000rpm and run to over 100mph in a falcon panel van. So i would be to quick to junk the stock stuff. I even cut up a couple of stocker two barrel manifold and ,made them into a twin two barrel setup, Ive not run this so I would be able to give any perfromance ideas for it, however it looked like it might have worked OK.
If your running a slushie, the keep the cam down to try and keep torque up, I wouldnt consider one with a small six.
A7M

I just took the calipers to the valves. They are 1.5" exhaust, and a bit over 1.8" intake. I'd have to pull them to get the hundredths and thousanths on those measurements, but the exhausts looked to be almost dead on 1.5".

I don't see how this could be an "earlier" head since it is an EFI head (has the injector notches on the intake ports). I guess it depends on your definition of "earlier". Also, there is significant partial shrouding of the intake valves, which I thought was part of the HSC design.

The intake I'm using is a Redline 4V. I think I may adapt it for a progessive 2V Weber, though. Should be a piece of cake since the intake is an open-plenum design.

Injector notches came in about '85 but the head was revised in '86 or '87 also. That could explain their presence.

SixFoFalcon":1juqvilg said:

My alloy crossflow head is one of the mid-80s, EFI-equipped, high-swirl designs with fairly small CCs. After milling and having the valve-work done, I'm probably looking at 48-50cc chambers.

The valves will be 2V 351C valves @ 1.656" exhaust and 2.045" intake. The rockers will be 1.72:1 Cleveland roller-tip rockers.

The cam will be a mild one, since the displacement is only going to be ~200 CI. I'm thinking about the Crow #14678 or #14613.

Things I need to figure out:
Dizzy... this is going to be a little bit of a headache. It looks like my '72 dizzy with Pertronix is going to be a little too close for comfort with the intake crammed right on top.

Target CR. I'm thinking that 10-10.5 is doable with the alloy head if I'm careful about the combustion chambers. Am I way off? With the high-swirl head design, would I want dished pistons, or flat-tops? I have to admit, I'm quite in the dark on this one. This car is by no means going to be a daily-driver, so fuel cost is of little concern. The thing is, the CR needs to be a consideration from day 1 of the buildup. It will help me determine how much overbore I want (I prefer to keep it under .040 for the sake of retaining cylinder wall strength/stiffness), how much decking I want, and whether I just want to skim the head or mill it more deeply. Looking at the CCs, I probably don't want to shave too much off the head because they are pretty shallow as it is.

Thoughts?

Click to expand...

The stock valve and port sizes should support enough airflow to easily push over 225hp mark. Using a mild cam, stick with those. Bigger valves net you nothing with that combo.

Flat top pistons should work fine with those chambers. For that CR on pump fuel, shoot for a quench distance of no more than .045". You should get that with a zero deck and a stock head gasket, but if need be, you could probably get away with a .005" deck (piston out of the hole).

The shortest stock distributor I could come up with is the load-0-matic. You could load the pertronix, add an MSD6, and advance the ignition with an MSD advance box. The next shortest thing I found is a DII equipped with a 1973 small early cap. It looks like a pre-electronic cap but is a screw on instead of clips.

My hybrid runs well, starts easily with the Strombergs. I haven't had a chance to put it on the road, but it seems like it should be pretty strong. More carb would be a good thing. The Mikuni six pack is still on the shelf but Megasquirt is also an option.

I wonder how an EFI-hybrid would do with turbocharging? You'd need to find pistons to lower the compression, though.

None of the modifications are in high stress areas, as far as I can tell...so it shouldn't hurt longevity?

A 200/EFI hybrid would also be a very light engine...hmmmm....

Ben

My US 200 hybrid tips the scales at 295 lbs without manifolds or fluids. And it is 2" shorter than the Aussie 200/250, making it a very compact package.

Bare 200 blocks are light and only weigh about 110 lbs, IIRC. I once astounded the neighbor by bending over the Locost and lifting the block out of the car by hand. He thought it was a complete engine, though!

Injector notches came in about 82. All series 2 alloy heads have the notches. Injected heads were different in that they came with larger intake valves. Although the ports were never modified by the factory to actually take advantage of the larger valve. If you remove the intake valve you will see a shoulder sticking out directly below the valve seat.
As for valves, I'm certain that cleveland length valves will fit. The stem dia. is the same but the head sizes certaintly are not!

As for carbys, My 250 is fitted with a 600 double pumper...
I would recommend using a 500holley 2 barrel. The 600 is far to big!
A friends speedway car was running a rebuilt 250, with head work, raised CR. and a mild cam, on the dyno made 115kw at the wheels with a 320 or 350 progressive. So I loaned him my 600 vac sec and 4 barrel manifold.
Motor made slightly more power, but fattened up the torque curve somewhat. Out on the track he says it made a huge difference...
His 2 barrell was fitted to a std manifold via an adapter plate.
A 500 holley should be about right... But if you have your heart set on a 4 barrell, go for a 390 or a 465.

Thanks for all the tips folks. I guess I got confused when someone told me they used Cleveland valves in their crossflow, and I haven't bothered to check the various diameters and whatnot. I suppose my best bet is to get an order together from OZ like this:

Valves
Springs & retainers
Cam (close to stock, relatively low lift)
Head gasket set (x2)

Things like bolts/studs, carb parts, pushrods, valve locks, guides, etc. can are generic enough to be sourced locally.

In my garage, I happened across an old Carter 2-bbl from a big ford six that ran well and never seemed to need much adjustment. It would be good for dialing things in once the engine is assembled. Once everything is up and running I can play around with something progressive like a Weber DGV or a baby 4-bbl.

For the dizzy, I have my '64 Load-o-matic w/ Pertronix as a last resort, and I have a '72 pre-Duraspark dizzy that I can put the Pertronix in too. It looks like the '72 dizzy MIGHT leave enough room for the plug wires but it's going to be close. I'm going to go hunting for a late '90s Mopar V6 in the junkyard, as many of them had a low-pro "crab" cap to clear the hood. Diameter looks to be close to what I need so maybe with some machining I can put the two together. If not, my options become:

-Cobble up an offset drive mechanism for the dizzy to get it out beside the intake rather than under it.
-Use the load-o with the MSD advance as MustangSix suggests. I'm 2/3 of the way there since I've got a Pertronix and MSD 6AL already installed.
-Go to an electronic DIS, which I have some experience with, but would still be time-consuming and expensive.

some nissan v6's have a crab style cap. I think vg30 series as in 300zx and maxima

Yes, the Nissan VG30E/ET engines (Maxima, 300ZX, Pathfinder, Mercury Villager, Quest, some 200SX-SE and pickups) have a crab-style cap.
I think the VG30DE/DET/DETT (later 300ZX, Maxima, etc, with the dual-overhead cam version) had a DIS and no cap, but I'm not sure.

If you need measurements, I have a spare cap in the garage (I'll be back from sea after September 10) from my 300ZX; I know the 84-89 turbo and nonturbo 300ZX used the same cap and it cost about $15 when I bought it. My understanding is the 84-88 Maxima distributor is the same as well.

I think the Nissan distributor is shorter and fatter, but I never measured.

I am sure the lower body is different; so you might adapt the cap but I doubt the dizzy could be easily fit.

Ben

Greywolf":3ovohqih said:

I wonder how an EFI-hybrid would do with turbocharging? You'd need to find pistons to lower the compression, though.

None of the modifications are in high stress areas, as far as I can tell...so it shouldn't hurt longevity?

A 200/EFI hybrid would also be a very light engine...hmmmm....

Ben

Click to expand...

That's kind of my question/route. I'm wondering about the valves at the moment and have just started to dig around to see about suitable options. Are there suitable replacements for boosted applications available?

I'm home, and I forgot about this.
Let me get measurements.

As far as the hybrid engine...I'm thinking Mike's FSPP head may be the hot ticket. If I didn't have my XFlow-EFI engine in the garage, I'd probably just build an FSPP engine for my Zephyr. As it is, I think my Datsun project will be all US/FSPP, especially for ease of transmission hookup to US block.

Ben