It seems we're missing the reason for the question. Not that I've got an answer, but reading the original question, the desire for a hydraulic clutch has nothing to do with pedal pressure or effort, rather it's a clearance or spatial issue that's creating the desire for hydraulics.

4th Series 426/433. Production ran from 8/1926 thru 7/1927, your # is a bit more than halfway thru the production run.

I haven't looked it up but the most likely difference would be a small change in either the centrifugal or vacuum advance profiles, or both, due to the larger displacement of the 1938 motor. Just as a generalization, best performance will be with the correct one though the difference may be small.

Hi BDC, can't say I have a feeling for it one way or the other. But I suppose one would expect heads to be more common from the years where aluminum heads weren't offered, given approximately equal number of engines produced.

Dave (Flackmaster), the 34 8-cylinder distributor is a 3-bolt mounting. 1933 uses the same distributor but I'm not sure if the mounting base is the same. And my 242511 head is"residing" on my spare '34 Eight motor, meaning the studs and holes match, but its not a running motor, the head is just stored there for convenience. Sorry for not being clear about that.

I don't recall the answer offhand but I think you want to check the distributor mounting and especially the attaching bolt pattern, I believe those earlier heads have different distributor mounting.

Why don't you just use the phone and call Daytona and ask them? I've always found them very ready and willing to help.

According to Hollander's Interchange, 34-38 320 engine heads interchange. That would be 1100-1-2, 1200-1-2, 1400-1-2, 1500-1-2, and 1603-4-5. A notable appearance difference is the provision for a cylinder head thermostat on the later heads which will require a little creativity for the upper radiator hose fitment.

Though Hollanders specifically excludes earlier heads, I suspect they are incorrect and believe a 1933 1001 head will also interchange and would have the same water outlet neck as the 1100-1-2. I believe my 1100 has a 1933 head, I'll check and post the casting number shortly.

PS - no casting number on the head, but the later head on my spare 1934 Eight engine has casting #242511.

And note that with the later heads you'll be going from 14mm to 10mm spark plugs.

Can't rule out ignition but most likely is a fuel supply issue. I'd start by checking fuel pump delivery volume and pressure, and the fuel bowl level in the carburetor. You might also just put on a timing light and check the timing and a qualitative check to insure the mechanical advance is functioning. On the timing, don't forget you have two independent 4-cylinder ignition systems and each has to be timed separately (assuming you have the stock ingition system).

Fuel filters clean? Condition of the flex fuel line from the frame to the pump?

As to your question about speed, yes - in proper tune your 1100 should be able to accelerate smoothly right up to its top speed (about 86 mph when new). But as to sustained highway speeds, with the original 4.69 rear axle and poured rod bearings you should think of 45-50 mph as your maximum speeds for sustained highway driving. A few mph more if you converted to insert rod bearings. If you want more highway speed capability, consider an overdrive or more advantageous rear axle ratios though these are pretty scarce and no current supplier that I'm aware of.

The Standard Auto-Electrician's Manual Edition T and other sources I looked at all agree that the CD-800 was original equipment unit. My Hollanders doesn't go back far enough to show interchanges,if no one else comes along with interchange info (and there is a lot of interchange between OD units), why not just call Jason at AER, that vintage Owen Dyneto units are a bit of a specialty of his.