Slick761

Gotta grind the seats to match. I don't have the tools needed personally. The three angle increases flow. You can get necked down valves as well.

5-90

I'm roughly familiar with the Oz Hemi - I've not seen one in person, but I understand the theory. Making a cross-draught inline is a pain with a distributor in place, but somewhat doable. I'd want to convert to COP/DIS anyhow (for a few different reasons - more later.)

They'd have to be. I'd probably leave the exhaust where it is (simplifying undercar work, since it would remain the same) and relocate the intake to the other side of the engine. Switch to COP/DIS.

I'm entirely too familiar with it - having owned a 1980 CVCC Accord. Basics:

- CVCC came out when "lean burn" was gaining vogue to reduce HC and CO emissions (typically at the expense of NOx - making a three-way cat and EGR both even more "necessary.")
- In order to achieve reliable ignition with a lean operating mix (I think it ran about 16.5:1 in the main combustion chamber,) a "prechamber" was used running a rich mix (around 12.5:1 or so - just this side of Rich Burn Limit) with it's own small - about 3/4" - intake valve, a chamber about the size of a grape, and a secondary circuit running a single small barrel in the carburettor (the carburettor proper was a Keihin three-barrel - the smaller "secondary" barrel ran the RBL mix, and the two "primary" barrels ran in tandem feeding a mix somewhere around Lean Burn Limit - LBL.)
- The combination of the RBL/LBL mix gave a final aggregate FAR of something like 14.5:1 - or just about stoichiometric.
- In order to manufacture the head effectively, the valve seat for the second intake valve couldn't be made into the head. Therefore, the smaller intake valve was mounted as a removable "cartridge" setup, where you'd use a large deepwell socket (21m/m? 22m/m? I don't recall) on a hex around the valve spring seat to back it out. You could then clamp the spring on the bench, remove the spring locks, and strip the valve cartridge down to its component parts (valve, spring, keeper, locks, and cartridge body. The seat was part of the cartridge body.)
- Lapping the valve was usually done by pulling slightly on the stem and spinning it, because the suction cup on the typical lapping tool was larger than the valve head.
- After service, the valve cartridge would be reassembled and reinstalled.

The spark plug threaded into - and fired into - the small combustion "prechamber."

I can't find a good picture of the valve in relation to the head, but here's the head. The "paired" valves on the far side are the standard intake and exhaust valve set, while the smaller valve assemblies on the near side of the pic (there are only three, one has been removed) are the auxiliary intake valves running the different mix -

http://img.photobucket.com/albums/v8...231.jpgI'm trying to look up what a 3 angle entails, but why can't a 3 angle valve job be done at home? is it computerized or something? Seems like you could just get three cutters, do the median one first and trim off the upper and lower sides with the other two cutters? So far, with what I've found so far it doesn't look like the valve matches all three angles anyway, just one. I've only done singles before, though.[/QUOTE]

A "three-angle" valve job is an attempt to get something closer to a "round surface" profile at the valve seat - the area is machined to a 30* angle, a 45* angle (the valve seat proper) and a 60* angle from the head deck line. This provides a more gradual change in flow direction, helping to preserve laminar airflow and therefore flow efficiency. Even less common is the "five-angle" valve job (15/30/45/60/75,) but the utility of that beyond the more common three-angle valve job is still being debated. Both are attempts to get closer to a "rounded corner" profile in that area.

http://img.photobucket.com/albums/v8...30231.jpg(edit) Ok, found this:

http://grassrootsmotorsports.com/for...g/32113/page1/

and it sounds about like what I was thinking, however, I had forgot that it would be best to get other work done along the way (guides and whatnot), so perhaps I'm not feeling as cool about it. That is unless my dad has the tools already. Never know what he's got.[/QUOTE]

Reasons to go COP/DIS?
- Six ignition coils means greater coil saturation time per spark, meaning greater energy output per spark.
- Elimination of the secondary HT ignition leads, means greater safety in the secondary HT/HV circuit
- Six ignition coils means six ignition coil drivers, which means that each coil may be tuned to give optimum spark timing for that cylinder (peak pressure should hit at 12*ATDC to give maximum leverage on the crank arm.)

Going with a solenoid valve setup would probably be more easily done by doing a "cartridge valve" setup akin to what I described for CVCC -screw the valve in, and retain it with a circlip (after all, you don't want it working loose.) This could allow for a lower profile for the solenoid pack, by allowing part of it to be actually inside the head casting (without having to cast it into the head.) The valve cover would essentially become a "dust cover," since top-end lubrication just became unnecessary. This would simplify the lubrication of the engine, and probably help to increase life of the engine coolant (and could probably be done with a modification of the existing head design, rather than a "clean-sheet" setup as with the CSRV. COP/DIS would also allow for outright elimination of the distributor, and the SYNC drive should be made smaller than the current OEM - and making it a few inches shorter.)

Going with either a pentroof or Hemi setup would allow for the spark plugs to be moved to the top of the head, and if the extra work is willing to be done, then DFI could also be done and the plug and injector could potentially be inserted at angles from vertical. While this would probably improve fuel mix formation, you lose the cooling effect of spraying the back of the intake valve with raw fuel - however, this will also prevent the formation of major deposits on the intake stem. The direct injection setup would also be more responsive to cylinder tuning (I know I'm wandering pretty far afield from a "drop-in and go" setup, but if we've got a clean sheet of paper to work with...)